Document 6b0VxYnBazY45BV214JRqMYe1

A introduction to pvc resin technology Only a small number of polymers with a particularly advantageous combination of properties have found a major place in commerce. Although PVC as a polymer has found a significant position in today's marketplace, this polymer is chemically one of the least stable of the common polymers; and its exploitation came about only through the development of proper technology for handling the resin and the discovery of suitable stabilizers. The factors responsible for the rapid growth of PVC are considered to be: low cost the ability to be compounded into a wide range of flexible and rigid forms good physical, chemical, and weathering properties utility and a broad range of large volume application processability by a wide variety, of techniques Poly(vinyl chloride) (PVC) was first characterized more than 100 years ago, but did not start to gain commercial importance until the 1930s. One of the earliest applications utilized a vinyl chloride-vinyl acetate copolymer as a coating for the interior of beer cans. The problems caused by its inherently poor thermal heat stability were overcome by the development of suitable stabilizer systems. Progress in PVC technology has involved a complex inter action between resin development, effects of additives, and equip ment design, as well as market demands. Today, PVC is the second largest volume thermoplastic used in the U.S. and is the lowest priced of the five leading plastics. This low cost, along with its great versatility, is one of the major reasons for its large share of the plastics market. PREPARATION OF VINYL CHLORIDE The phenomenal growth in PVC production has been largely due to the availability of low cost monomer. Current commercial processes for production of vinyl chloride can be placed into two classes. The first class involves the gas phase reaction of acetylene with hydrogen chloride using mercuric chloride or other heavy metal HgCl2 f{C=C!I + HC1 - - > CH2=CHC1 1 VAB.0001130502 halides as catalyst. The advantage of this acetylene process is that no hydrogen chloride is produced. With the second class of processes, ethylene dichloride (EDC) is first produced by the reaction of ethylene with chlorine which is then subsequently pyrolyzed to yield vinyl chloride and hydrogen chloride. Manufac turers employing the ethylene route with the resultant HCl by product could combine this with the acetylene process in order to utilize the HCl. 2HC1 + 1/2 02 ------------> Cl2 + H20 Cl2 + Cll2=Cll2 ------------> CH2Cl-Cl!2Cl ch2ci-ch2ci -he--t - > ch2*chci + HCl Our Lake Charles Vinyl Chloride Monomer plant uses the newer oxychlorination process in which hydrogen chloride is oxidized using air or oxygen to produce chlorine in water. The chlorine then reacts with ethylene to give you EDC. This EDC is then pyrolyzed at higher temperatures to give you vinyl chloride plus HCl. The HCl is then reacted with oxygen to convert it back to chlorine. PROPERTIES OF VINYL CHLORIDE The following table lists the physical properties of vinyl chloride monomer. Because vinyl chloride is gaseous at normal atmospheric temperatures, it is normally stored under pressure as a liquid. Color Odor Molecular Weight Boiling Point Freezing Point Density @ -20C 20C ,5 Refractive Index D Viscosity @ -20C @ 25C Surface Tension @ 20C Flash Point, COC Explosive Limits in Air Vapor Pressure @ 0 C @ 20C @ 40C Solubility of Water in VCM Solubility in Water @ l atm. Heat of Polymerization Colorless, water clear Pleasant, sweet 62.5 -13.7C -153.8 C 0.983 g/ml 0.910 g/ml 1.398 0.274 cps 0.193 cps 22.27 dyn/cm -78C 4--22% by vol. 25.1 psi 49.2 psi 87.6 psi 0.11% 0.5% 720 BTU/lbs Vinyl chloride may be stored in ordinary steel cylinders, Lank cars, and storage tanks. Although vinyl chloride is stable under normal conditions, nevertheless, over a considerable period of ( VAB.0001130503 time, polymer can build up in storage tanks and pipelines and, therefore, need to be inspected and cleaned at regular intervals. Many problems caused by the presence of impurities in monomer have been largely eliminated. Some of these impurities encountered are acetylene, iron, hydrochloric acid, oxygen, water, acetaldehyde, butadiene, and residual EDC. Under normal production routine, vinyl chloride is used without further purification. However, even a trace of oxygen in the monomer will react to form peroxides, which may cause difficulties. The initial reaction product appears to be a monomeric material soluble in the vinyl chloride monomer. Subsequent decomposition or rearrangements lead to a polymeric peroxide of limited solubility which can initiate further polymerization. The presence of ounts of water and acid in the monomer accelerates this formation of peroxides and polymer. Thus, it is quite necessary to maintain the monomer free of air, water, and acid, both to obtain the best quality resins and to minimize handling difficulties. caaasnci of vinyl chloride polymerization Vinyl chloride monomer (M) is polymerized efficiently in the presence of a free radical source (I*). The general reaction scheme and initial kinetics are typical of a free radical chain reaction and is shown below in ^gure 1. Initiation Propagation Termination Chain Transfer To Monomer a Chain Transfer To Other Chemical 1-1^21- M iy. IM' + Mg^ IMgM* IMXM* M^ IMXM+M- IMXM* +C ^ IMXM + C Figure 1. The chemistry of vinyl chloride polymerization. The rate of initiation (K. and K^) is dependent on the type and concentration of initiators) and the temperature of polymeriza tion. The rate of propagation (polymerization, K~) is also depen dent on initiator(s) and temperature, but it becomes complex because of the presence of the precipitating polymer phase. The molecular weight of the polymerizing PVC chain is dependent on the rate of termination (K,) by transfer to monomer which is tempera ture dependent. In addition, molecular weight can also he affected by chain transfer to another chemical (chain transfer agent), and A VAB.0001130504 I this rate of termination (Kc) is dependent on temperature, type, and concentration of chemical additive. Because K_ is much greater than K,, the resulting polymer chain will he of lower molecular weight. Experimental work has shown that the free radical polymerization of vinyl chloride is thought to strongly favor a head-to-tail struc ture. The low order of crystallinity is attributed to the non regular positioning of the chlorine and hydrogen atoms about the carbon atom. The degree of crystallinity of commercial PVC is estimated to be about 8-10%. Chain branching is believed to be low. What branching does exist is attributed to free radical transfer from a growing chain to the back of the same or another polymer molecule. Cl Cl Cl -CH2TCH-CH2-CH-ai2-CH- Four types of processes are used for the commercial manufacture of PVC: suspension, mass, emulsion, and solution polymerization. About 83% of all PVC is produced by the suspension process, about 8% by the mass process, about 8% by the emulsion process, and about 1% by the solution process. SUSPENSION POLiiiZRIZATTON PROCESS The suspension polymerization process involves the mechanical dispersion of vinyl chloride in an aqueous medium. Suspending agents, or protective colloids, which are water soluble polymers are used to help stabilize the monomer droplets. Monomer soluble initiators, such as peroxypercarbonates, peresters, and peroxides, are used to initiate the polymerization. Figure 2 illustrates a typical suspension PVC process flow diagram. The process begins with the charging of the process ingredients, as shown in Figure 3. While being agitated, the mixture of these ingredients is brought to the desired polymerization temperature, usually by circulating hot water through the reactor's jacket. Since the polymerization of vinyl chloride is an exothermic reac tion, the heat of reaction must be removed in order to maintain the desired polymerization temperature. This heat can be removed by ci rculating cooling water through the reactor jacket. Refrigerated water and specially designed cooling baffles can improve heat removal. Also, stainless steel-lined carbon steel reactors have an advantage over solid stainless steel or glass-lined reactors. Several producers have developed reflux condenser technology to improve the reactor's heat removal capacity. V ( VAB.0001130505 Rcevrd Oump Roector VCM VCM Tank flncovory 8tnd Fluid Tank CMlrlfugt Bud Oryor 8l9rQ SSo * Figure 2. Typical suspension PVC process flow diagram. Vinyl CMortdu ProctM WIm . flmpwBIm Aqania CtlMcata Initiator 100 ISO aos 0.01-2.0 0.00 Figure 3. Typical suspension PVC recipe. The pressure in the reactor is the sum of the partial pressures of vinyl chloride and water at the polymerization temperature. Conversion % Figure 4. Conversion rate for vinyl chloride polymerization. VAB.0001130506 t As shown in Figure 4, the temperature and pressure remain constant during polymerization up to about 702 conversion* at which time the reactor pressure begins to drop because of the absence of liquid monomer. The rate of conversion increases throughout the polymerization* but begins to decrease at pressure drop. The polymerization time is dependent upon the amount of initiator charged. The reaction is then terminated at a specific conversion depending on product quality requirements. The unreacted monomer and PVC slurry are then transferred to a dump tank* and the unreacted monomer is degassed into the recovery system and stored in a separate tank to be recycled back into the reactor with the other charge ingredients. The discovery in 1973 that exposure to vinyl chloride resulted in the increased incidence of a rare form of liver cancer (angio sarcoma) resulted in fundamental changes in the PVC industry. In addition to air emission and water discharge regulations in general* PVC producers must now comply with OSHA employee vinyl chloride exposure standards and the EPA vinyl chloride emission standards. These standards are met by additional monomer recovery in a stripping process where the slurry is heated and stripped of very small amounts of residual vinyl chloride by contact with steam. Continuous steam stripping is carried out in a trayed stripping tower by injecting steam directly into the slurry. This stripping process is carried out in such a way as to minimize heat exposure of the resin to avoid r~tsin degradation. The reactor is then rinsed with water. In order to meet OSHA and EPA regulations* employee exposure and reactor opening emissions are eliminated by using high-pressurc-water cleaning equipment that operates in a closed reactor. Then the reactor's internal surfaces are treated with chemicals to prevent polymer buildup. The reactor is then ready to be recharged. Although the suspension polymeriza tion of vinyl chloride is a batch process* after the reactor is emptied* the downstream processes can be carried out in a continuous manner. The stripped slurry is then held in a blend tank before being centrifuged to produce a wet cake having a water content of 18-25%. A two-stage fluid bed dryer is used to dry the resin to below 0.3 wt% water. The resin is then stored in silos and is usually shipped in bulk by either rail cars or trucks* or packaged in bags or gaylords. PVC plants before the 1970s contained many small, batch reactors. Large reactor technology allowed the reactor size to be increased from 2,000-10,000 gallons to 15,000-50,000 gallons. These large reactors increased productivity, lowered plant costs, improved product quality and uniformity, and reduced vinyl chloride exposure* and emissions. More and more older small, reactors have been shut down and replaced with modern large reactors. VAB.0001130507 A MORPHOLOGY OF PVC In the suspension polymerization of vinyl chloride, the bulk monomer phase is dispersed in water by vigorous agitation, and the droplets produced are stabilized by the presence of a suspending agent. The correct amount of this suspending agent is used so that the monomer droplets undergo controlled coalescence during polym erization to give rise to an irregularly shaped grain having an average particle size of about 150 microns (Figures 5 & 6). The size, shape, and porosity of this grain is very dependent on the type and concentration of the suspending agent used and on the type of agitation (e.g, stirrer speed, agitator type, size and shape of baffles). Microscopic examination of this PVC grain shows it is composed of an agglomeration of sub--grains which are about 40 microns in average size (Figures 7 & 8)* These are the stabilized monomer droplets which, during the initial phase of polymerization (about 5-15% conversion), coalesce to form the PVC grain. Further micro scopic examination of these sub-grains show they are made up of primary particle agglomerates which are about 5 microns in average size (Figure 9). These are formed during the early stages (2-5% conversion) of polymerization by coalescence of primary particles. These primary particles are about 0,7 microns in size and are formed at very low conversion (less than 2%), *^ Within the monomer droplet s*.joended in the water, the first aggregate of polymer chains that precipitate* about 50 in number, form the smallest PVC species identified so far, the microdomain, which is about 0.02 microns in size. These microdomains coalesce to form a domain, A domain is the nucleus of the primary particle, contains about 1,000 microdomains, is about 0,2 microns in size, and is only observed at very low conversions (less than 2%). This term is only used to describe the 0.2 micron species because it immediately starts to grow to become the primary particle. The microdomain and domain are not features of PVC morphology at high conversions since a growth of these species with conversion oblit erates all memory of them, leaving only the observable primary particle. From this discussion, it can be shown that the formation of suspen sion PVC takes place through a series of interconnected aggregation steps which can be represented by the scheme in Figure 11. Suspension PVC particles usually possess a pericellular "skin" or "membrane" which extends almost continuously over the entire outer surface of the grain This skin is formed during the early stages of polymerization (less than 5% conversion) and has been shown to be a copolymer of vinyl chloride and the suspending agent(s). Since this skin is semi-permeable, it does contribute to the overall porosity of the resin, hut not nearly to the extent as does the primary particle agglomerate. VAB.0001130508 f Several different types of PVC grains can be obtained during the suspension polymerization process* The most desirable grain has a semi--permeable skin and good porosity where the pores are open and evenly distributed throughout the grain. A less desirable grain contains closed pores which are not connected to the skin. The least desirable grain is the solid grain containing little or no porosity. The production of these different types of grains is mainly determined by the choice of suspending agents. REACTOR PROCESS VARIABLES AFFECTING THE PROPERTIES OF SUSPENSION PVC Molecular Height The various different grades of commercial PVC are mainly deter mined by their molecular weight. In the absence of other active chemicals, the molecular weight of PVC is almost entirely deter mined by the polymerization temperature; the higher the polymeriza tion temperature, the lower the molecular weight. In the presence of chain transfer agents, the molecular weight Ls lowered depending on the type and concentration of agent. Thus, low molecular weight resin can be produced at lower polymerization temperatures using chain transfer agents. In the opposite manner, the use of chain extending agents will allow the production of high molecular weight resins at higher polymerization temperatures. Particle size is important for various PVC applications. For rigid extrusion, a more coarse resin is desired so that all of the grains are well fused in the extruder and no unfused fines are left to cause weaknesses in the final product. For plasticized applica tions (calendering, blown film), a finer resin is preferred so that there are no large unfused grains which will cause imperfections in the finished product. Within a given reactor with a given agitation system, the particle size of PVC is dependent upon the type(s) and concentral:ion(s) of the suspending agent(s); the higher the concentration of suspending agent(s), the finer the resin. Since the PVC grains are a distri bution of sizes, particle size is usually described as an average particle size and the broadness (or narrowness) of the distribution is described as the coefficient of variation (the standard devia tion divided by the average particle size); the smaller the coef ficient of variation, the more narrow the particle size. Particle size can also be expressed as the percent through a set of standard mesh screens (ASTM test method D--1705--82). VAB.0001130509 f Porosity The porosity of PVC is most important in controlling not only the absorption of plasticizers but also the desorption of vinyl chloride during the recovery/steam stripping process. A good understanding of the mechanism for the development of porosity in PVC is necessary to insure good quality resin. The various grades of PVC can be further divided into porous (for flexible applica tions) and non-porous (for rigid applications) resins. The process of plasticizer absorption is generally believed to occur by a diffusion mechanism in which two separate mechanisms The first process is a very rapid capillary filling of the intergrain (pores between the resin grains) and intragrain (pores within the resin grains) pores. The second process involves the diffusion of the plasticizer molecules into the molecular PVC chains. This second process is the rate-determining step in the absorption of plasticizer and is controlled by the size of the sorbing sphere the primary particle agglomerate. Since it is known that one way to increase the absorption rate of a fluid into a soonlida is to reduce the size of the solid particle, it can be concluded that the diameter of the agglomerate increases, the porosity of the resin decreases, Thus, controlling agglomerate is the important step in establishing the porosity PVC resin. There are several process variables that affect the porosity of PVC. These are as follows: Polymerization Temperature - For a given set of polymerization conditions, reaction temperature has a very large effect on porosity; the higher the reaction temperature, the lower the porosity. This is because the agglomerate size increases as the reaction temperature increases. * Conversion - Conversion is also found to have a very large effect on resin porosity; the higher the conversion, the lower the porosity. Again, this is due to the agglomerate size. Resins polymerized to a higher conversion have larger agglom erates than those polymerized to a lower conversion. Agitation System - Agitation is of fundamental importance in the PVC suspension process. Together with the suspending agent system, it determines the particle size of the finished product and other properties, such as porosity. Generally, the more power (e.g. higher speed) the agitation system puts into the reaction mixture, the higher the porosity. Also, different agitator blades and baffles can affect resin porosity. A 9 VAB.0001130510 w* * Suspending Agent System - Given a particular type of agitation system, a particular polymerization temperature, and a reason able conversion (75-85%), the suspending agent system has a great influence on resin porosity. The primary suspending agent is usually a water soluble organic polymer, such as a polyvinyl alcohol, a substituted cellulose, or a mixture of the two. Generally, the lower the surface tension of the suspending agent(s), the higher the porosity ol. the resin. The primary suspending agents are chosen not only for their ability to control particle size but also for their ability to produce porous resin. However, the degree of surface activity for these chemicals is limited, thus additional secondary suspending agents are used to further increase porosity. A variety of materials can be used, such as nonionic or anionic surfactants and low molecular weight polyvinyl alcohols of very low degree of hydrolysis. These secondary suspending agents increase porosity by either lowering the surface tension between the vinyl chloride and the aqueous phase or by stabilizing the primary particle agglomerates during polymeri zation. There are several ways of measuring and expressing the porosity of PVC. Among these are the following: Porosity - This is measured by mercury intrusion and expressed cc/g (ASTM D-2873-70). Also other descriptions of the porosity of the resin are available from this single measure ment: void volume (cc/g), a measurement of the intergrain pores (volume between the resin grains); average pore size (microns), a measurement of the diameter of the pores within the grain, and distribution of pore sizes. Cold Plasticizer Absorption (CPA) - The amount (%) of plasti cizer that a resin will absorb at room temperature (ASTM D-3367--75). This is a measurement of both inter- and intragrain porosity and should be about the same value as the mercury intrusion porosity measurement. Brabender Dry Time - Under a given set of test conditions, this measures the time (min) that it takes a given amount of resin to fully absorb (giving a dry powder) a given amount of a particular plasticizer at an elevated temperature (about 80 C) using a torque rheometer for mixing (ASTM D--2396-79). *lhis is primarily a measure of the filling of the inter- and intra-grain pores and the rate of hot plasticizer absorption (diffusion into the resin molecules), but measures, to some extent, the capacity of the resin for plasticizer. Gel 1 - In this test, a plasticized milled sheet Is pre- pared under given conditions and the number of gels (fishoyes, hard particles, glassies) a re counted in a given area (ASTM ( VAB.0001130511 ! D-3596-77). A gel is a PVC grain which does not absorb plasticizer at the same rate as the other grains. This is usually due to the inaccessibility of the pores to the plasti cizer. The number of gels will decrease to a constant number as the length of time on the mill increases. Microscopic Examination - A simple technique for qualitatively examining the porosity of PVC is placing the resin on a microscope slide and immersing it in a liquid having a re fractive index similar to PVC and, after equilibrium, viewing it at low magnification (lOOx) with transmitted light. The internal morphology of each grain can clearly be observed. Bulk Density Generally, the bulk density (g/cc) of PVC (ASTM D-1895-69) is in opposition to its porosity; as porosity decreases, bulk density increases. Thus, all of the process variables that affect porosity also affect bulk density. The most important process variable is probably the choice of the suspending agent system. i For rigid extrusion applications, the rate of output of the extruder (especially twin-screw extruders) is directly dependent on the bulk density of the dryblend which feeds the extruder. Thus, it is important that this dryblend have ajiigh bulk density. For wire and cable applications, the electrical conductance of the PVC resin is an important property. PVC must be produced which has extremely low conductivity (or very high resistivity). Generally, this is done by using deionized (DI) water as the process water and not contaminating the resin with non-DI water or resin made with non--DI water. STEAM STRIPPING AND DRYING PROCESS VARIABLES AFFECTING THE PROPERTIES OF SUSPENSION PVC Color The color of PVC resin is usually measured by a colorimeter and is described by a L-, a-, and b-value. The L-value is a measure of its whiteness; the a-value is a measure of its pinkness; and, the b-value is a measure of its yellowness. In order to assure a white, non-pink, non-yellow resin, antioxidants and killing agents (to prevent further polymerization at high temperatures) can be added to the slurry before steam stripping and drying to prevent degradation. A VAB.0001130512 I* Heat Stability Good heat stability of PVC is maintained by tlw proper care gLven to the steam stripping and drying processes, Too high a temperature or too long a residence time will decrease resin heat stability. Again, the addition of antioxidants and killing agents will aid in maintaining good heat stability. Heat stability is usually measured in these three ways: Static Owen Heat Stability - PVC is milted into a given plasticized compound and subjected to a given temperature in an air-circulating oven. Coupons (or chips) are removed from the oven over a given period of time until the milled sheet has degraded to black (ASTM D-2115-67). The resins are compared to a standard resin of the same molecular weight and similar quality. If the t ime--to--black is less than the standard resin, then the heat stability of that resin is poor. Dynamic Hill Heat Stability - PVC is mixed into a given rigid dryblend and placed on a two--roll mill at a given speed and temperature. Coupons (or chips) are removed from the mill at given intervals of time until it turns dark or sticks to the mill. Again, the resins are compared to a standard and judged to be less stable if the milled sheet turns dark or sticks to the mill before the stands-d. Brabender Heat Stability - PVC is mixed: into a rigid dryblend and placed in a torque rheometer at a given speed and tempera ture. The amount of time it takes from fusion to degradation is a measure of its heat stability. Both of these properties are mainly dependent on the proper use of the dryer. If the dryer temperature is too low, then an excess of volatiles will be present in the resin: if the dryer temperature is too high, the amount of contamination (dark specks which are usually burnt resin) will be too high. Also, contamination can be caused by a dirty dryer. Even if the PVC is dried to the proper dryness, there may be static built up on the resin which will cause poor flow properties. The static can be eliminated or reduced in the drying process by the addition of an antistatic agent (e.g., dry steam). VAB.0001130513 HASS POLYMERIZATION PROCESS Elimination of the requirements for suspending agents and other additives prompted considerable effort to develop a suitable commercial process to polymerize vinyl chloride by a mass process. Extensive research efforts were undertaken during the 1940s and 1950s to develop a successful mass polymerization process because of its potential for both cost savings (reduced raw material usage and elimination of the centrifuging and drying operations) and product improvement (reduction of chemical residues and elimination of the pericellular skin). Initial attempts followed the fairly conventional approaches of using a single reactor. A major break through came in 1963 when Pechiney-Saint Gobain (later to become a part of Rhone-Poulenc and now a part of Chloe Cheraie) developed a two-stage process. Licensees are now producing PVC by this patented process in Europe, Japan, United States, and other countries The first reactor is vertical and fitted with a high intensity turbine--type agitator to give vigorous agitation to obtain the desired particle-size distribution. Only monomer and initiator are charged, and polymerization proceeds to about 10% conversion at which point the formed particles are dispersed in the bulk of the liquid monomer as a sort orf PrvVuC sliusnh ixnn monomer,. A monomer soluble initiator is used, and the particle size is controlled by the speed of the agitation. Tucn the free--flowing mass is trans ferred to a horizontal reactor fitted with a "ribbon blenderf,-type agitator. More monomer and initiator are added and the polymeriza- tion continues being slowly stirred, At about 20Z conversion, all of the liquid unpolymerized monomer absorbed into the porous structure of the grains leaving only a dry powder The second reactor is about twice the size of the first which feeds up to five second-stage reactors.. The heat of pDoollyvmmeerriizzaation is removed through reflux condensers, and polymerization continues to about 70-80% conversion. The unreacted monomer is recovered, followed by high-temperature stripping; and the reactor is emptied by means of an air flow. The product is transferred to a large classification system which screens out the oversize particles (about 3-8% of the yield) and then is transferred to silos without the need for centrifuging or drying. Continuous updating of the process has occurred with a progressive increase in reactor size. A very significant development has recently occurred with the introduction of a vertical second-stage reactor which is easier to empty and clean, produces less oversize particles, and gives higher-quality product. PROPERTIES OF HASS PVC PVC grains produced in the mass process are very round and uniform in nature. They have the same morphology as suspension PVC grains A VAB.0001130514 except for the semi-perraeable skin, They have an average particle about the same as suspension PVC, hut have a very narrow particle-size distribution. Since there is no suspending agent present, they do not have a pericellular skin, as seen in Figure 10. They have about the same porosity as suspension PVC and the same reaction variables (except suspending agent) affect porosity (e.g. polymerization temperature, conversion, agitation). Chemi cals can be added to increase porosity and also to improve heat stability. A very positive feature of mass PVC, especially in rigid extrusion applications, is its high bulk density resulting in a high dryblend bulk density which gives high extrusion rates. In the U. S., most of the mass resin is used in rigid applications. Mass PVC is very similar to suspension PVC, and they compete in almost the same application areas; however, they are not compati ble. Mixing the two leads to powder-flow problems. Thus, they must be used separately and can not be mixed in the same storage silos. EMULSION POLYMERIZATION As in suspension polymerization, emulsion polymerization involves the dispersion of vinyl chloride in an aqueous medium. The most important characteristics of an emulsion process as distinguished from suspension polymerization are the use of wetting agents or soaps emulsifying agents and a water-soluble initiator. Agitation, though necessary, is not as important as it is in a suspension process since the soap is present to maintain an emulsion or latex. Protective colloids are usually used to ensure latex stability. The PVC particles obtained by the emulsion technique are about one micron in diameter, which is about 100 times smaller than those made in the usual suspension process. As in a suspension process, there is a distribution of particle sizes. Also, as in the suspension polymerization technology, the amount of emulsifier will affect the final size of the latex particles. Emulsion polymerization may be described in the following manner: At the concentration employed, most of the soap exists In the form of micells. These tiny micells serve to stabilize a portion of the vinyl chloride which is only slightly soluble in the water. The remainder of the monomer exists as small droplets. A free radical generated from the water-soluble initiator enters the micell, meeting a monomer-rich environment; and a rapid polymerization takes place on a small scale. Polymerization, therefore, takes place primarily in the monomer solubilized in the soap micells rather than in the dispersed droplets of monomer because the free radical formed by the initiator goes into these micells. As polymer forms, the monomer in the micells Is replenished by migration from the droplets; thus, the emulsion polymerization can be described as taking place in the water phase rather than in the ( VAB.0001130515 monomer-droplet phase. As these micells grow and the further polymer is produced, these small particles are then protected by the soap used for the polymerization. When the polymerization is complete, which is usually at about 30 percent solids, the residual monomer is removed, and the latex is generally spray-dried to give a fine powder which is packaged. SOLUTION POLYMERIZATION The Union Carbide Corporation was responsible for the development of solution polymerization techniques for vinyl chloride/vinyl copolymers. The methods employed produce highly uniform copolymers of various molecular weights. Applications are mainly solution coating resins where the high quality and uniformity justify the higher manuafacturing cost. Polymerization is carried out in solvents in which the polymer is insoluble, resulting in precipitation of the resin during polym erization. These copolymers do not contain suspending agents and are also free of homopolymer impurities. (^POLYMERIZATION alymerization of two monomers, either monomer can add to itself or the other monomer j>-esent. The composition of the copolymer obtained from a specific mixture of monomers is deter mined by the two reactivity ratios of the corresponding monomers. The polymer thus formed at any instant will be different from the monomer mixture. Where the reactivity ratios of each monomer are both less than one, the polymer tends to alternate. If one of the reactivity ratios is greater than l, and the other reactivity ratio is less than 1, the polymer will be richer in monomer of the reactivity ratio greater than 1. To prevent formation of a polymer with a wide distribution of composition, it is generally necessary to add the more reactive monomer during the course of the polym erization. The limitations of PVC, as recognized early in its development, led to efforts for modification by copolymerization. Improvements were required in heat stability, melt viscosity, solubility, and processing temperature. Copolymers have thus become an important part of the total consumption PVC. The chloride-vinyl acetate copolymer predominates as the most useful copolymer of vinylchloride, and its applications include coatings, floor coverings, and phonograph records. The vinyl acetate content of most commercial copolymer ranges from 1/2 to 15 percent. The greatest flexibility in solubility is obtained at the higher levels. The major applications for the vinyl chloride/viny1 acetate copolymers are those in which low melt viscosity, low processing temperatures, freedom from external plasticizers, and solubility are required. V'AB. 001130516 The reduction in melt viscosity and increased flexibility are attributed to interference by the bulky acetate groups with intermolecular associations. Copolymer i/.at ion with vinyl acetate reduces tensile strength, heat distortion temperature, chemical resistance, abrasive resistance, and heat stability. Another important group of copolymers is that formed by the copolymeriza tion of vinyl chloride with olefins. The introduction by Air Products of a vinyl chloride-propylene copolymer is directed towards improved processing characteristics, permitting higher production rates and a lower processing temperature. The reduced processing temperature allows lower stabilizer requirements and permits less expensive nontoxic stabilizers for application, such as blow-molded bottles. The propylene content in this copolymer is about 3 to 5 percent. These copolymers have been approved by the FDA for food applications and may be used for packaging at tempera tures up to 150 r. Another modified PVC which is not strictly a copolymer is chlori nated PVC. An early attempt to change the chemical structure of PVC to improve processibility, solubility, and heat stability was through chlorination* Chlorinated PVC is obtained by chlorinating PVC particles in a water suspension. A patent was Issued to B. F. Goodrich describing this process. REFERENCES Since this is only meant to be an int nology, a complete bibliography is not If the reader is interested in further pursuing this subject matter, then the following references will be very useful and current. If the reader wishes to delve even deeper into the literature, these books have many more references than what would have been found here. R. H. Burgess, Manufacturing and Processing of PVC, MacMillan Publishing Co., Inc., 1982. G. Butters, Particulate Nature of PVC, Formation, Structure and Processing, Applied Science Publishers, ltd., 1982. W. V. Titow, PVC Technology, Fourth Edition, Elsevier Applied Science Publishers, 1984. ( VAB.0001130517 r VAB.0001130518 ti>* u r H I ill i'i i or st rue 1 nr<* fs ; i i >n |ir;i i ii : MOOX VAB.0001130519 i Figure 9 Interior structure of suspension PVC grain. 10,000X VAB.0001130520 . i Chain IM* + M Growth Initiation First Agglomeration Second Agglomeration Precipitated Chains Micro-Domain 0.02 Microns 1 % Conversion A Particle Growth Third Agglomeration Domain 0.2 Micron Primary Particle 0.7 Micron 1-2% Conversion Primary Particle Agglomerate 5 Microns 2-5% Conversion Fourth Agglomeration Sub-Grain 40 Micron Grain >150 Microns 5-15% Conversion Grain 150 Microns 75-85% Conversion Figure 11. Schematic representation of the formation of suspension PVC VAB.0001130521 HIW .diii -'--til >wnfnji-c-d " r-rrj^f--i ii+r' ii M T RBR fW l I )\ }t i i i i ji i h i ! Ii VAB.0001130522 J PVC IN-DEPTH RESIN TRAINING SCHEDULE WEDNESDAY, OCTOBER 14, 1987 ABERDEEN, MS 7:30 7:45 8:00 8:15 9:00 9:15 10:15 10:45 11:00 12:00 1:00 1:30 2:30 2:45 4:00 Welcome & Introduction History of PVC Vinyl Chloride (VCM) 1. VCM Manufacture - Oxychlorination Process 2, Properties of VCM Polyvinyl Chloride (PVC) 1. Mechanism of Polymerization - Free Radical 2. Structure of PVC Break Polymerization Process 1. Mass 2. Solution 3. Emulsion 4. Suspension Vista Suspension Process Technology 1. Reactor Design 2* Resin Handling Procedure Break Polymerization Recipes Lunch Resin Morphology Effect of Process Variables on Resin Properties Break Research Projects 1. VCM Absorption 2. Hard Particles 3. CPA's 4. IR Adjourn A VAB.0001130523 X/e/rTlATO/^ L-2-Z3 o )l t>\ - i - E'tUv 1 We./. L- 55^ o -cO IJ l*-" * i 4 A 59>5 f<^*5 1* {'C^O<y AtO^Ml^nOA+e. VAB.0001130524 To _ From Calculation Sheet A ^ 1 /x 7 ' w- v s tA- 9 O *T c- c3\rv_i C, <D lDc) ^ Y ^^ - V/JV\y 1 uiXvx^ u --^c\ (>f* C> li o' (i C -c/ o O L 5"SX/ \ ^O -o o w c to a ^tp Yfo K/sdc^C. o 6t G -c_ I'-v ^ W \r^o Vi-e- V- 'his\s'4r^r[ "-^4r ^A^ul O A- >r (i VJ PT sl^rcj k,r^ /^-O Ck V* <S^cJc(e / 4^3 kr-ees^, tJdubx S> -^G*S CAW*j( ^w- L 'NCi-tecLVetf'' u IS- & o - QrL Couw<^( l* S--M67 Oodles V- N^u4-:r2P~&^--' L, L~ Made By _______________ Dato____________ _______ Pag iof V3-2 )G-S Job No. Title VAB.0001130525 To Fror i crt.- U-r Vv' A-V e Calculation Sheet 2 VISIA A /%,(v\b fZLAC (v ,,> EV 6.7*< V, <5.7*1 ^ fc- V. > l (X /O 'S-oO Me f <3'^ /V 7->.S~ < *3. l.(X t 1.0X uO*Ai II? (. I** ^s~ -ttst <?u A) <^'oO & tr 042- 13-? *? / , 63&S~ S-^'S"' jfci&K. L -sc ^ u~ *> L. -t^ &a.'NW OrA &fc ll A-^Gvo^ /SPA cm.; IK Mi IvAAO'' * fcr -Ik? .OoWtH 4 & & (*) * O) ` B*. Sfc Job No. _ Title 74<- Wt PK K VAB.0001130526 $k To_____ From__ Calculation Sheet A ot Made By_______________ Date Page-of V3-2( G-S a k~L Job No. __________________________ Title VAB.0001130527 VISTA CHEMICAL COMPANY RESEARCH & DEVELOPMOW DEPARTMENT PVC PROCESSING TECHNOLOGY AREA RICK QUY MOREY OSBORN CHARLIE MCDONALD RICHARD LAHIERE ALAN WARDWELL ROD HAMMONS BETH LEVEN A VAB.0001130528 PTC IN-DEPTH RESIN TRAINING SCHHX1LE WEDNESDAY, OCTOBER 14, 1987 ABERDEEN, MS 7:30 7:45 8:00 8:15 9:00 9:15 10:15 10:45 11:00 12:00 1:00 1:30 2:30 2:45 4:00 Welcome & Introduction History of PTC Vinyl Chloride (TCM) 1. TCM Manufacture - Qxychlor ination Process 2. Properties of TCM Polyvinyl Chloride (PTC) 1. Mechanism of Polyne r ization - Free Radical 2. Structure of PTC Break Polymerization Process 1. Mass 2. Solution 3. Emulsion 4. Suspension Vista Suspension Process Technology 1. Reactor Design 2. Resin Handling Procedure Break Polymerization Recipes Lunch Resin Morphology Effect of Process Variables on Resin Properties Break Research Projects 1. TCM Absorption 2. Hard Particles 3. CTA's 4. IR Adjourn 4 VAB.0001130529 08/04/67 VISTA RESEARCH AND DEVELOPMENT SURFACTANTS RESEARCH Director O. C. Kerfoot B.J. Montgomery C.L. West L.A, Butler C.G. Custer Adm. Supervisor L.I. MurrLson CHEMICALS TECHNOLOGY RESEARCH Director R. L* Poe J-M. Slavens Research Associate W.R. Carredlne Safety/Environmentai R.B. Martin POLYMERS RESEARCH Director S. E. McGuire Assoc. Director H. J. Hall B. C . K ing C.D. Hemple Applications Technical Service Technology Supervisor K.F. Cox P A. Morris D, L. Smith S. L. Ring G. L. Russell D. L. Heppler Products Technical Service New Products Process Research Microbiology Technology Supervisor K.L. Matheson Sr. Technology Supervisor D.L. Wharry Sr. Technology Supervisor B.E. Leach Technology Supervisor A.M. Nielsen J.L. Anderson J.O. Gregg P.A. Schwab S.K. Sarpolus C.K. Snell W.A, Dickenson L.R. U. Weerasoorlya M.L. S.J. Hercyk J. B. M.A. Moore R.D. D. G. Holliday Shannon U inde r Godbehere Mathews S.J. Renbargec Industrial Chem ( Technology Development Analytical A Analytical B Sr. Technology Supervisor J.T. Fenton Sr. Technology Supervisor D. R. We Ime r Sr. Technology Supervisor J.E. Yates D.A. S.L. L.B. J.L. R.T. D.J. U.L. Barclay Baxter Decker Hackett Jackson Lewis Sorensen M.E. D.R. T.M, C.C. Bose Rubik Latimer Mercy M. M, D.J. HO. E.L. De \ round Mahoney Perkins Sones R.L. U.L. M.M, G,R. J.A. Beggs Brown Chavez Madderra Robson Dryblend Compound Resin Application Process Technology Sr. Technology Supervisor R.G. Mleure Technology Supervisor S.H. Hookanson Sr. Technology Supervisor J.L. Irvine Sr. Technology Supervisor R.B. Quy J.M. Janes P.J. Klein G.A. Butler C.E. Hoover J.E. Ingram B.M. Wit toer J.L. Cox L.G. Haefner D,B. Fenton L.G. Ciopton L.U. Darst R.J. C.J. M.E. A.W. R. R. W.C. Lahiere McDonald Osborn Wardwell Hannons Turk k VAB.000113(^30 History of PV | VAg.0001130531 1835 1845 1836 1872 1900s HISTORY OF PVC FIRST RECORD OF VCM VINYL CHLORIDE APPEARED IN LEHRBUCH DER ORGANISCHEN CHEMIE WHITE POWDER FORMED WHEN VCM EXPOSED TO SUNLIGHT m FIRST CONFIRMED PVC ACADEMIC INTEREST ONLY LIEBIG KLOBE REGNAULT BAUMANN VAB.OOOl 130532 19061913 mb 1928 1929 VCM FROM ACETYLENE + HCL AND POLYMERIZED WITH HEAT AND PEROXIDES SOLUTION PVC WITH HEAT AND U.V. COPOLYMERS PVC PLASTICIZED KLATTE & ROLLETT % OSTROMUISLENSKII REID & WILEY SEMON ViS&.OOOl 130533 I 19301990 1937 1939 19901960 1960 BREAKTHROUGHS PVC PASTES PVC/PVAC - WATERPROOFING STABILIZERS EMULSION SUSPENSION - EASY PROCESSING FULL-SCALE PRODUCTION SMALL PRODUCTION USE DOUBLED EVERY THREE YEARS UNPLASTICIZED USES SURPASSED PLASTICIZED BECAME CHEAPEST POLYMER ON COST PER UNIT WEIGHT BASIS GERMANY VAEbQOOl130534 I Resin LDPE JW HOPE PP PS ABS (MILLION LBS) Domestic Demand_______ Sales of Domestic 1985 1986 1985 1986 8143 8491 8790 8769 6806 7087 6720 7197 5823 6197 6661 7017 4413 4697 5275 5790 4054 4392 4108 4452 981 1035 1015 1074 VAB.0001130535 1 * t-'J FACTORS RESPONSIBLE FOR PVC GROWTH 1. Low COST. 2. Can be compounded into wide range of flexible AND RIGID FORMS. 3. Good physical, chemical, and weatherable proper ties. 4. Utility and broad range of large volume appli cations. 5. Processability by a wide variety of techniques. 6. Less energy intensive overall. PVC USES HO% PIPE/FITTING 11X FLOORING 11% COATINGS 7% WIRE & CABLE 8% FILM & SHEET 1% BOTTLES 3% RECORDS 8% MISCELLANEOUS EXTRUSION 2% MISCELLANEOUS MOLDING 4 5% EXPORTS 8% OTHERS VAB.OOOl130537 CONSTRUCTION PACKAGING ELECTRICAL FURNISHING AUTOS RECREATION APPAREL MEDICAL MISCELLANEOUS * 60Z 10X 71 6Z 4Z 3Z 3Z 2% 51 ALSO VAB.OOOl130538 (MILLION LBS/YR) Supplier BPGoodrich Occidental Formosa Shintech Georgia Gulf VISTA Borden Air Products 1545 1520 1038 1000 850 US 660 500 1370 1360 952 1000 800 m. 605 500 175 160 86 50 55 VAB.0001130539 HISTORY OF VISTA'S PVC ACTIVITIES . 4-A 1963 ACQUIRED CARLON PVC PIPE CO. 1964 ACQUIRED APEX TIRE AND RUBBER CO. (COMPOUND) AND THOMPSON CHEMICAL CO. (PVC RESIN) FROM FAIN FAMILY. 1964 EXPLOSION AND FIRE AT THE HEBRONVILLE MASS. PVC PLANT. 1964 ABERDEEN MISS. PLANT STARTED-UP AND THE ASSONET MASS. PUNT BUILT. 1967 R & D MOVED FROM PONCA CITY TO ASSONET MASS. 1968 VINATEX (ENGUND) CAME INTO EXISTENCE. 1968 FTC MADE CONOCO DIVEST OF ITS ASSONET MASS. PUNT (SOLD TO OLIN INDUSTRIES), COMPOUNDING FACILITIES IN RHODE ISUND (SOLD BACK TO THE FAIN FAMILY ETECKNQR-APEX3), AND BUY OUT STAUFFER PORTION OF THE VCM PUNT. 1968 CONOCO PUSTICS FORMED FROM CARLON PIPE AND PVC PUNT IN ABERDEEN AND HEADQUARTERED IN WILTON, CONN., INCLUDING R & D. 1970 URGE REACTOR PUNT STARTED-UP IN OKUHOMA CITY. 1972 SOLD CARLON TO INDIAN HEAD INDUSTRIES, SHUT DOWN THE WILTON FACILITIES, MOVED R & D TO PONCA CITY, AND FORMED CONOCO CHEMICALS. 1975 ALL SMALL REACTORS SHUT DOWN. 1976 DIVESTED OF OUR HOLDINGS IN VINATEX. 1978 to 1981 PVC RESIN, DRY BLEND, AND COMPOUND CAPACITIES INCREASED. 1984 VISTA POLYMERS INC. FORMED. VAB.0001130540 ! i  syAB.OOOl130541 A |<)CO: ox37chlorination/cracking of dichloroe VAB.0001130542 I Color Odor v Molecular Weight Boiling Point Freezing Point Density a -20C a-20c Refractive Index Rq Viscosity a -20C ..... a 25C Surfact Tension a -20C 91 Fiash Points COC Lxplosive Limits in Air Vapor Pressure a 0L a 20C a 40c Solubility of Water in VCM Solubility in Water a 1 atm. Heat of Polymerization Colorless, Water Clear Pleasant, Sweet 62.5 -13.7C -i53.8C 0.983 g/ml 0.-910 g/ml (7.60 lbs/gal) 1.398 0.274 cps 0.193 cps 22.27 dyn/cm ~78C 4-22% BY VOL. 25.1 psi 49.2 psi 87.6 psi 0.11% 0.5% 720 BTU/lbs VAB 10001130543 VAB.0001130544 i MECHANISM OF POLYMERIZATION QR--.-rC.-0 -O f o* 2.PR0P0GATI0N note head to tail addition AAV-C. c`i C 4, C.HCI c> ^ 'r'f~exrvSi6 H> u /VSA-C-C* H Cl mzc=chci t4 3 <T *4 S kar- ies-ir*, 3A\f! v 2 A fl <vAB.0001130545 0 t C,U^.V i <2S\*J i-K "* I 4.TERMINATI0N Recombination /Vs/\ H Cl disproportionation + Cl ^VW-C -C 4 HM -8b HH rt ^ a W| * ^ A rxssu VAB.0001130546 <3 ^ o^ l ok. 'K.XS VAB.0001130547 PROBLEMS ;E><UWC4rA/ &- - fVLe, P0o l ^c-A^^ole- * * VAB.O601130549^ / i L 4 Jf ' r ' , ,, '* I vAb.000113055(^ m A I C.tfY^T QUA/ (T) QlArry r<0 LA- C_ </.- i VAB.0001130551 Polymer Properties 1. Glass transition temperature, Tg (C) 2. Compression molding temperature F 3. Compression molding pressure psi 4. Injection molding temperature F 5. Injection molding pressure psi 6. Specific gravity 7. Tensile strength psi 8. Elongation percent 9. Compressive strength psi 10. Flexular strength psi 11. Impact strength ft-lb/in (1/2 IN X 1/2 in notched bar, izod test) 12. Hardness, Rockwell 13. Flexular modulus 105 psi, 73F 14. Tensile modulus 105 psi 15. Thermal conductivity 10"4 cal/sec/sq. cm./1 (C/cm) 10. Specific heat, cal/C/gm 17. Thermal Expansion, 10"5 in/in/C 18. Deflection temperature F at 2G4 psi FIBER STRESS 66 PSI FIBER STRESS 19. Water absorption 24 hr,, 1/8 in thick PERCENT 20. Effects of sunlight 21. Effects of weak acids Typical Values 75-105 285-400 750-2,000 300-415 10,000-40,000 1.30-1.58 6,900-7,500 10,000-16,000 0.4-20 65-85 (Shore D) 3-5 3.5-6.0 3.5-5,0 0.25-0.35 5.0-10,0 140-170 135-180 0.04-0.4 Varies with FORMULATION None VAB.OOOl 130552 l2. Effects of strong acids 23. Effects of weak alkalies 24. Effects of strong alkalies 25. Effects of organic solvents None to Slight None None Resists Alcohols, ALIPHATIC HYDRO CARBONS, OILS, SOLUBLE OR SWELL IN KETONES AND ESTERS; SWELLS IN AROMATIC HYDROCARBONS VAB.0001130553 r i 4fr. > * &< -m A * *0 1)Mass h 2)Solution 3)Emulsk>n 4)Suspension % VAB.000113^54 1 f I I VAB.0001130555 J POLYMERIZATION MASS (BULK) Manufacturer: Pechiney St. Gobain Two-step batch Polymerization starts in VCM phase, then precipitates. Advantages: p 1. Very uniform, porous particles. 2. High bulk density. 3. Free of suspending or emulsifying agents. Disadvantages: 1* Difficult to control temperature. 2. More expensive than suspension. i Market: Same as suspension except for molding / \ i j ! ( wL r t i VAB.000113055 p SOLUTION Manufacturer: Union Carbide Polymerization in a solvent then precipitates form copolymers* Advantages: 1* Same properties as bulk* Disadvantages: * 4 1* High Cost -- 44</lb. ft Market: Very limited (beer can liners) VAB.0001130^57 ! EMULSION Manufacturer: BFG P/^r^C-^V S' 1. *1* \[ Soaps used to form micelles in water. \/+ ^ \ V <cv^- -1 \ o /diP (lip 2 Water-soluble initiator encounters VCM in micelles \ + t 4 \* 3 Diffusion from droplets replaces polymerized VCM* Advantages: 1* Prepare high MW resin* 2m Produces very small nonporous resin* Disadvantages: 1* High contamination level of soap* 2* Poor heat stability. 3* High Cost -- 57</lb. Market: Plastisols, used for coatings ( i I t VAB.0001130558 f SUSPENSION Manufacturers: Conoco and many others 1* VCM droplets suspended in water 2 Initiator is VCM soluble. Advantages: * Easily controlled temperature. .2 Easily filtered and dried. a 3. Cheap -- 27$/lb. 4 Disadvantages: 1. Small change in conditions alters properties. 2. Not as pure as mass or solution. Market: Extrusion, molding, calendering A VAB.0001130559 I CHARACTERISTICS OF PVC POLYMERIZATION PROCESSES Ingredients: Monomer(s) Initiator Solubility Suspending Agent Reactor Agitation Market Rank (Lb. Basis) Mean Particle Diameter End Use 4 * Suspension * PVC A VCM VCM Protective Colloid Low Shear 1st 150 ym Rigid Flexible Extrusion Film Blown Calender Molding 4 Resin Polymerization Type Emulsion Mass or Bulk PVC PVC VCM [ Water Soap <H 1 High Shear ;* t 2nd i 10 ym j Pastes Latex Dispersions Creams VCM I VCM None High then Low 3rd 150 ym Rigid Flexible Extrusion Film Blown Calender Solution PVC VCM/Vinyl Acetate VCM None Low Distant 4th Solution Beer Can Liners m VAE&8001130560 i WLiAJW* VAB.0001130561 VCM RECOVERED A S# CONDENSER (CONOCO) SIZE L&M) STEAM STRIP SILO VAB.0001130562 SLURRY FROM BLEND TANKS >----------------------- AIR PREHEATER FUEL GAS t RESIN DRYING SECTION PVC MANUFACTURE ATM. CENTRIFUGE CENTRATE TO HEAT RECOVERY ROTARY DRYER DUST COLLECTOR ROTARY VALVE SIFTER ROTARY VALVE *1 AIR /- AIR BLOWER CWS 7Y CWR TO SILOS ;ViSB.0001130563 CHARGE POLYMERIZATION RECOVERY l> STRIPPING PUMP RINSE fa CLEANING EVACUATION 11 111UooHcC<cOxJ* 11 5 1 1I1 1 > X UCco<cDJr 1 u<_ CO CYCLE HIGH PRESS WATER POLYMERIZATION SECTION PVC MANUFACTURE VCM TO RECOVERY INERT VENT RINSE WATER AND CLEANING SOLUTION EVACUATION ATMOSPHERIC VENT [LCUD 1 ICC cohC<cOc* 11 11 11 l1w 1H IHz COOLING WATER SUPPLY COOLING WATER RETURN CITY WATER CENTRATE STM WATER CHARGE TANK STM uoiiIquj: CULLS SLURRY T VAB.0001130564 FRESH VCM FROM STORAG block flow diagram VAB.0001130565 VCM (V) FROM REACTORS f VCM RECOVERY SYSTE PVC MANUFACTURE I I L PROCESS RECOVERY SYSTEM DIRECT CONTACT CONDENSER DRY VENT HEADER i SEAL WATER SEPARATORS TO INCINERATOR >> RR RECOVERED VCM RECEIVER KNOCKOUT POT VACUUM PUMP CWR H CWS COMPRESSOR L SEAL WATER ^ RETURN t A WET VENT HEADER / J STEAM SUPPLY MISC 0 EQUIPMENT PURGES VAB.0001130566 REACTOR SIZE Aberdeen Four 18.000-gal Four 22,000-gal Two 33,500-gal OKC Six 18.000-gal CAPACITY Aberdeen -425 MM lbs 5465 5.0% 5425 13.7 5385 Type 1 22.5 5385 Type 3 35.0 5305 11.3 5265 12.5 OKC -2#0 MM LBS 5385 100.0% VAB.OOOl 130567 VCM WATER TYPICAL CHARGE SIZE ABERDEEN 18,000 (lbs) 47,000 56.000 22,000 (lbs) 47,000-58,000 56,000-69,600 33.500 (lbs) 78,000 98,000 VAB.OOOl130568 Jk TYPICAL PLANT RUN TEMPERATURE/PRESSURE PROFILE 230 210 190 170 Pressure 150 F Temperature 130 120 90 70 50 Time Legend: A. Charge complete heatup started. B. Pressure at 90 psig KA/AO added and steam injection started. i 140 120 100 psig 80 60 40 20 VAB.0001130569 TYPICAL HEAT RELEASE CURVE MAXIMUM HEAT REMOVAL CAPACITY OF CONDENSER r sfi( > POLY TIME pJ /JLeV- e C'-U"&ns \ i r\ W> VAB.OOOl 130570 Jb A Grade 5265 5305 5385 5415 5465 (MOLECULAR WEIGHTS) Monomer Poly Tenp 700 950 1200 1325 1475 150 150 134 127 119 Inherent Molecular 0.66 0.74 0.92 1.04 1.10 40.000 59,375 75.000 82,800 92,200 VAB.0001130571 5465 Automotive Wire Vinyl Car Tops Toys 5385 Pipe Seat Covers (Calendering) General Flexible Applications Siding Garden Hose Shoes (Flexible Molding) Profile Molding 5265 Pipe Fittings 5425 Building Wire Communication Wire General Purpose Calendering Vinyl Car Tops Flexible Automotive Molded Parts 5305 Rigid Pipe Fittings Semi-Rigid Calendering VAB.0001130572 I Resin Morphology -- Shape * VAB.00mi30573 i 4 f T Grain Size 9 Grain Shape I Debris 9 Agglomerate Size 9 Porosity i i ll P I i i! VAB.0001130574 i STAG SPECIES INITIATION R* VCM Coiled Macro Radicals 1st AGGREGATION STEP Micro * Domain 2nd AGGREGATION STEP CONVERSION SIZE When Formed Finally V -50 ft 1-2 2 100 - 200A Domain (Primary Nucleus) * 0-l-0`2jjm GROWTH (1HTRA- PRIMARY) Primary Particle 3rd AGGREGATION STEP Agglomerate | Scale 4-10* 0*6 -0-8pm (Primaries \ now J 0'2"0-4um/ 1-2pm GROWTH (INTER-PRIMARY) Agglomerate 902 2-10 pm Sub Grain 4th AGGREGATION STEP Grain 40/*m 30% 150/un VAB.0001130575 EFFECT OF PROCESS VARIABLES ON RESIN PROPERTIES A/ Property A. Molecular Weight (Inherent Viscosity) B. Particle Size Distribution C. Bulk Density D. Porosity (Brabender Dry Time, Cold Plasticizer Absorption, Residual VCM) E. Gels F. Resin Color G Heat Stability H. Moisture I. Electrical Properties f Process Variable i. Polymerization Temperature 2. Chain Transfer Agents 3. Chain Coupling Agents 1. Suspending Agent Concen tration 2. Agitation 1. Static 2. Resin Particle Shape 3. Additives 1. Degree of Conversion of VCM to PVC 2. Polymerization Temperature 3. Additives 1. Cleanliness of Reactor 2. Agitation 3. Additives 1 a Heat History 2. Antioxidant 1. Heat History 2. Killing Agent 3. Antioxidant 1. Drying Efficiency 1. Type Initiator 2. Additives 3. Type Poly Water VAB.OOOl130576 PVC PROPERTIES--REACTOR RELATED Resin Property Molecular Weight (MW) (Inherent Viscosity) Particle Size Distribution (Average Particle Size [y] and Coefficient of Variation) Bulk Density (gms/cc) Plasticizer Absorption (Brabender Dry Time [min]) Gels (Fish Eyes) Process Variable Polymerization Temperature Chain Transfer Agent (CTA) Suspending Agent (SA) (Methocei ) Conversion Process Chance Higher Temperature; Lower MW Lower Polymerization Temp with Increased Amounts of CTA More SA; Finer the Resins Kill Polymerization After Pressure Drop Conversion Additives Clean Reactor Charging and Killing Procedures Higher Kill Pressure; Faster Dry Time Addition of QMS Adequate Cleaning and Rinsing of Reactor Proper Charge Sequence and Initiator Addition Along with Proper Killing VAB.0001130577 Resin Property Moisture Contamination Static Flow Residual VCM Gardner "b" Color and Heat Stability (Static Oven, Dynamic Mill, and Brabender) PVC PROPERTIES--DRYER RELATED Dryer Dryer Chem Wash Dryer Steam Stripping Dryer Steam Stripping Antioxidant Better Control of Dryer Clean Dryer Clean Chem Wash Filter/Tank Add Additional CaSt Proper Steam Stripping Procedure Proper Dryer Conditions Proper Steam Stripping Procedure Increase Level VAB.0001130578 O.C. TESTING * Q.C. Test ta 1. Inherent viscosity 2. Moisture 3. Contamination A. Bulk density 5. Screen 6. Gels 7. Dry time 8. Gardner "b" color 9. RVCM LO. Heat stability (oven) LI. Static flow ABD Routine once/hr. every 2 hrs. every batch every batch every batch every batch every batch every batch every shipment i* Spot every day 3/w* eek OKC Routine X X X X ---- every shipment every shipment Spot X ------ 3/week X 2/week VAB.0001130579 [ Plasticizer Absorption / VCM Removal Plasticizer Absorption VAB.0001130581 i 0 r\ Chart Rtcirtitr Diagram of Gravimetric Sorption Apparatus n--irch Roport No. 320-26-2-81 Pago 13 I NIV9 1M XVfl/ NIVO 1M Figlift 2. VCM Sorption Data VAB.0001130582 CRANK'S SOLUTION TO FICK'S LAW FOR SPHERES -An27T2Dt EXP 62-- C = VCN CONCENTRATION T = TINE D = VCN DIFFUSION COEFFICIENT d = PRIMARY PARTICLE AGGLOMERATE DIAMETER Rearrange to And Ai i i i VAB.0001130583 ) Research Report No. 820-26*2-81 Pape 22 A o J 10 20 30 40 50 60 70 TIME (min) Figure 11. Diffusion Curves for Conoco Resins VAB.0001130584 Research Report No. 820-26-2-82 Page 18 ( NIKI) 31/MIX AiJO A GO IO E o xc> 00 cvi JmO CD E CO * o crO JO co CVS o CD Eo CoD < io CL m *Ec CL cvi O S 111 e s CM C cvi VAB.0001130585 CONCLUSION 4 PRIMARY PARTICLE AGGLOMERATE DIAMETER CONTROLS VCM ABSORPTION AND BRABENDER DRY TIME. I 1 i ii J I i I \ i VAB.0001130586 * * A PVC HARD PARTICLES SYMPTOMS--SURFACE BUMPS OR IRREGULARITIES ON FLEXIBLE PRODUCTS NON-RESIN RELATED POORLY DISPERSED FILLERS. CLAYS. PROCESSING AIDS. OR PIGMENTS. CAUSES RESIN-RELATED 4 A. RESIN GRAINS WITH ANOMOLOUS MORPHOLOGY P B. MIXTURE OF MOLECULAR WEIGHTS GENERALLY. NO RELATIONSHIP BETWEEN HARD PARTICLES AND GELS. THAT IS. A TYPE 1 RESIN MAY HAVE HIGH HARD PARTICLES AND A TYPE 3 RESIN NAY HAVE LOW HARD PARTICLES. VAB.OOOl130587 RESIN-RELATED 1. GLASSIES, FISHEYES - NON-POROUS TRANSLUCENT PVC GRAINS. VERY DIFFICULT TO REMOVE BY EXTRA COMPOUNDING OR WORKING. 2. SHELL GRAINS - SIMILAR TO GLASSIES. ONLY SLIGHTLY MORE POROUS. ABSORB PLASTICIZER VERY SLOWLY. CAN BE COMPOUNDED OUT. HARD PARTICLE COUNT 1 TIME VAB.OOOl130588 CHAIN TRANSFER AGENTS 4 A I ji t if i Function: Terminate Macroradical Chain. Chain and Initiate New Effect: Terminate Chains at Shorter Length Than Normal for a Given Temperature. 4 Purpose: Allows Production of Low Molecular WEight PVC 4 at Lower Temperature (and Pressures). i VAB.0001130589 I CHAIN TRANSFER AGENTS CONOCO PVC Grade 5305 Monomer Units 900 Reactor Conditions Without CTA 152*F 170 psia 5265 700 160*F 190 psia Reactor Conditions With 2-EH 150F 164 psia 0.05 phm 150*F 164 psia 0.40 phm Reactor Conditions With 2-ME 150*F 164 psia 0.002 phm 150*F 164 psia 0.02 phm \ t VAB.dOOl130590 2-ETHYLHEXANAL PRESENT CTA ADVANTAGES * Liquid * No Odor * CompatIBLE * Safe * Uses Open Charging Methods * Cheap ($0.37/lb) DISADVANTAGES * Recovered with RVCM * Volatile from Resin * Low Activity (0.4 phm) * Condenser Fouling i A VAB.OOOl130591 1 * h REQUIRED CHARACTERISTICS OF CTAs MUST BE Highly Active Liquid Compatible with Reactor Additives * Initiators * Suspending Agent * Kill Agent Compatible with Dryblend Additives * Stabilizers (Pb, Ba-Cd-Zn) * Pigments Commercially Available MUST NOT Foul Reactor/Condenser s Contaminate RVCM Contaminate PVC Harm PVC Heat Stability Harm PVC Morphology Be Expensive I A / VAB.0001130592 t  Mercaptans o Phosphites Aldehydes Ring Structures 1 * At. * VAB.00Q1130593 l i l CHAIN TRANSFER AGENTS TESTED i CTA me thyl-3-mereaptopropionate mercaptoacetic acid 2-mercaptoethanol pentaerythritol tetra-3-mereaptopropionate ethylene-bis-mercaptoacetate n-buty i-3-tnereaptopropionate t *ipheny l*ant imony 4h | tc ^uiethylolpropane tri-3-mercaptopropionate hydroxyethyl mereaptopropionate 3- mercaptopropionic acid 2-mercaptopropionic acid ethyl-2-mercaptoacetate tetralin decanal 2-ethyIhexana1 dimethylmalonate ethylcyanoacetate isoocty1-3-mereaptopropionate tri-n-butyl phosphite Relative Activity (2-EH=l) 31 .0 26.0 23.0 18.0 16.0 16.0 15.0 15.0 14.0 14.0 4.5 2.0 1.6 1.2 1.0 0.5 no activity no activity no activity > I 1 1 t K i I I VAB.0001130594 PROPOSED CTA: 2-MERCAPT0ETHAN0L ADVANTAGES VERY ACTIVE * LOW USE LEVEL (0.02 PHM) * LOW COST ($0.93/LB.) NO CONDENSER FOULING EXPENDED DURING POLYMERIZATION * NO RVCM CONTAMINATION * NO COMPATIBILITY PROBLEM * NO RESIN ODOR NO PATENT PROBLEM IMPROVES PVC HEAT STABILITY/COLOR LOWERS W/M RATIO ALLOWS USE OF RVCM DECREASES POLY TIME DISADVANTAGES STRONG ODOR - 4 TOXIC CLOSED ADDITION SYSTEM DECREASES RESIN POROSITY # I I- VAB.0001130595 mA 4 VISTA POLYMERS RESIN SALES 1986 VS 1988 8 /8 7 >4 I A VAB.0001130596 A IR ACTIVITY TEAM TASKS .F " % f DETERMINE & RECOMMEND 4 1 HOW GOOD DO WE NEED TO BE? * i' 0 wf HOW GOOD CAN WE GET? HOW DO WE GET THERE? HOW MUCH WILL IT COST? WHO'S GOING TO DO IT? j HOW LONG WILL IT TAKE? A. k J- i* i1 . j I i i Fv VAB.OOOl130597 l: >r b 4 k. s f WHAT AFFECTS IR? \ ^ 1 "<%-L ANTISTATS a,- - * sA*- -V vvV- : . J * -r* r-'-'v ` . PJTi: " ' .>/. \V* r'i? ^ ' '`V' -VV'J. ^, >fV*fc/'-L, 's1 - Oi Av; *- j '***:'':> .'' %N n GLYCERINE C C*: ; - . 1 f . I-. ' tJ :i **. +J* - LUBRICAL 48N <-,j' -. > DRYv . *1 `:i. J .L , ' 4fc ' V frl>- -v ' ,.i - ^ '*-.p- f. l GNS CaSt /VArKv-, l :V . ^4- | . <' SODIUM vr \ ;v s t'j* BATCH MATER _ < -v v;4,` Vv.*:-' .1 J *- CLEAN HALL \ r - - ^v v'v, t>. o'--' v l. *V .<* fcA-' STEAM,J, i i. OTHER { ** 7^ ' k" ^ ' *T # "*** '< T- OTHER > t1 .* * P -L -<3 DRYERS ANTIOXIDANTS POROSITY ENHANCERS * VAB.0001130598 H . ......... ' ". ' I ' j r f " 7 P <I < t j. * ^ J . PARAMETERS t RESINS V 5415 5465 5385 PLANTS ABERDEEN OLD NODULE *d ABERDEEN NEW MODULE V C - ^ VAB.OOOl 13d599 yV r.. > y * I- Hi"* L* P- 1 f_cAf. n f * ^* ** >ri .- '-j * * >! lx ir j- t *^ H 'i P* , h. \ .A GUARD +? f ** V*v im 47 r*- - t UNKNOWN r. P4 A ' 'r^-. r H'* . ^_r _ ^* ' r .V-V ^L ,r ' .a A.- . , .* -- - ^ , ,, . H. 1- J 1 j -__ - . ^ -*;: i vT?; j*. ,., ' ' : '-kav >;.A ^= . i* fSc-H j> J'h, "J1 ..* / '>vTVAv ^ ifr: & iT v-i. V -*# ;* /A u-i rt :t * 4 S- t k> ' fcrtti i-1> * -i. <* A j ^ i fc :* '4 . *.: 1- :\ .i a# H**i9Us v-- -s y -VA1 1 *. ' H1' - ? ! - .**. A in r ` ^ I ^ ' h ^ ;1 I C-J 4.. Sv rfttA .'J- W"? -V ' HW V- ,.j r dw-ijr*t" V * - -A-*- H.r" :-i >< T ^->I***.* ; I i Vy fr1 ,4_, ^ i. -AAA. 4 . ' t*- - ifc '' v >*-- . %. - * * * ,- X- V ', t* X' " ' **-*,' " * A ` .. > -* * -e .. J ** \-;-5 m.*- **. *,7-r - '% ^ ,14*-? -, . ,*&* # .', hi " A -1_VZS . - * i > > Ju, " `l.\ Aj ,, * - ., A a* t-;1'ffff>( \ jrf ^VSS - --- ;' >;\'*&r-ai1'.- ~* / I -S>.' v Tf; i-,>`t\ - . V , * 'r- :- '.-* ^ : " V. '> >l'r A:. ' ` ' >. 1 X . : - \ v \ '.' I * % l ^ V 'v tt METS is supported -5* 1* .* . ""*"' " -J. * ^ " ' p*' '. A '.>/: =S *- \ .( ^L ^ f' ^. :a by paperclips run , through holes punched a on either side of copper*. V^H. , ^ t - *:' .*.' -' v. flf.. ' ^ ; -' Hr. j|* . ` X - * f- f -'k-* jr?>' ` ' xf-1 >jr ' 'r'f ' +J*- -SftA' . ... '-tf.wL. 'T'.^,,:k S'-* L - ^;i - : a: -A.' a; -l: -i:' r' > ^ ^ >' ..f<" ."**< ^ . ' . ''V -* '-*' i- ' i ^^X ^ '-*! Al'-v.v ^-- -;-*>> :-'V^ ,-. . '/" rt 't-d jT - >i. -L-;' +- "lJwJ 4\ 11 s'J *T :* .. :3 : ;- - 1 t*h `V* * n -> |eA* 4 -.V ' * * rV **ti*T'* ogSp-FrL- -;rr't*,u-*.*a,*.1- -< i.` * %i* . h. s * v * .. ^* 4 4 , * 'A > ,k - f>`. - ''* ,r - lT . , -.+ - - ` ...- la l * . V. w . -vs # ^ ' -, s 7+ s` ^ ^ '`V;-'' v' , ^ - A' u - *.- * ' * ,*. t :- ; a->- .7. ^ ' d|T a i-- j -* ` . ..JL k. fT _* ^ -Aj _.. 1 +^ VA.:;\AA:,*'.-:Aa;'ff?ec; ft * l^rJ^lcalK.AKW x .*Zk\rl A-Irl A-1 *a> ---- Ti * .eL< 5f? "rT- * ,r-^ Steel '* t ***&-**7t -<*r ^ e. ^ - . .' w A#6^:iAA-A ,, ;'!Y '..TV " A *-A\ :;:A', A v ; ^ _Ar - - - *r F'J, -r ' *7 7^;, * 'a -, k > 4. '" * .^ -3? CJ - ? ; --* ' .T- ; * v** * -.Vk , ' . ^ - . rI' -;/:'>`AC - . 'A1 * ^ rf , - . i # J i-* *'B .,, _; *<* *->'*. '*sV- % A 'V- : ' vl. * ---- .`-.r - - ,- V' jS 'v^A 1A-*. " `r*?! I I a:,7,'A''..^. ;y,.A>v I wv t 7 ',; - * l + 3t -,v Jt-- > 'f?7. *j*& S v:^ ^-71.* Ir 1 - . A-*' v L &. -JT-r. 11 . -A^ .7 f 7 .+>. V! - x.rjf4 M *+? l*fc- t `V 'j d r, 4^ lA.i ' r ' pi ,T. TJ .4^ IV-'Id !. . i. .A J * ^ t-T -U-* ^ S !> 4^ # p . y T' -T :*r. * 4. 't. J L j :>. .k V *4 `t % I,, * ^ '-v * * vi' ';7 : i^Avjfeff j 'V/ *As v> ^r -j, ^ m 'i~&-` C '.-" * 0 r A - \ :f---^ -v p '. .i - .'i'/v--.--- .v-iiw-i . y . .* * *r _ *e r w*`-> '5^,*'r-^'- . ' *- . .f^A -Vi * ^ >> :-Jlisi -7$[. +St*tkir*s>'i -V i -r * if^S; 4v* ". '.tv- a : = -F ^ * ;y*r' i* V' lr AA-^ * ! *. i v ' itJ n" V> V t. 4* M m r v *, > -j pjr. -vi / r- l+S a f' f !|. Water Inversion Vessel \ ^ J' j( j I VAB.0001130600 METS IR; % o f C o n tro l i Resin METS--IR Values 500 Comparison / 400 300 200 r 100 0 5415/LU 5415/DC Geon 30 Borden 5415/W Wash-AS RESIN TYPES l\ I Low Clqy Formula 5385 Abd 5385 OKC % I VAB.0001130601 Resin METS-IR Values Comparison 800 ------------------------------------------------------------------------------------------------- METS IRr % o f -C o n tro l 5415/LU 5415/DC Goon 30 Borden 5415/W Wash-AS RESIN TYPES f\ 1 Low Clay Formula C T 5385 Abd 5385 OKC VAB.0001130602 <r 'r * ? < i f' I b k * . ` >n ~k 1 J^W,1 ' * f 0 '*~ CKC Competitive l- J`- L-rv^- . . ' :. *.*}$ A (,.".''*. 17.*:', ` *.* y ^*p' J1 "^'Li^1^5".''-^r'"L * ' '"V .*- -*-1 ^ ^ 400 ^23a . ' l ~ .' r- II -T ' - * * r- iX*?c * .*%**-* '* - -v,. --. :: ^ ;.. *'/* *f' , T ' ^ '- * * *; .. .-; '~\\ ^v-- ' ' ' ,, .j ' i. - -*1 ^ 'VfT .* i- x UtWCL'S JRD (%) 300.- 640 CV-- *-s *-y J^T-.v*?\ ^ t '<J. P- \t ' -Wf1- t: -ii- rL '-X ii ^4!v - 1 .i t / ^ rh \r i Bqaiv Egaiv Equiv -r' >\ Vista Resins _K 5415 No Antistat 5415 BPA/Lubrical 5415 Dry Cast 230 260 290 i f- 330 1Q9L "f- j|j '> '4 266 T X\ v- #*1 . -j ,., .vv * &r V A . .*** o ** r * * * A ' "fl ' - A / t- lJ 1 '1 ' v*r.- \: ` T' jf . ` J"* ^ ^l ** * " i.b^r", *V ..*.-1 > :-#326 71 ^ 337 3 v* . 1 i , >-- - ^.-..< 1 . r^ 271 5415 No Antistat 5415 5415J4 b < 1 ^ -^i-/r..j BPA/Dubrical Dry Cast . `; r-> F* '3 . 1 d J < * -\ -J, u* /J r^Virf `. ' + * ' vV:.; y T * (' ''4* - -Z '.* " S" # ! jM r->h .. 5-^ -*-r :* r-^' / . ^ ^ ^ . r/ "1-^ - ,t. . 1 t ' p b*h** 1 - a* 1 'J- r ^ iV4V` Hi4t-. ^ * -1 " V -H Td. * -f j r '' 248 3^7 s . v ^v-.; - 1^, . K. : f1 '. * ^, - i './ - -->* -* ,,- . ^ ' ' ' '. ** T1 * F I * : :' > ^ '. * i j j.* Th ^ / p h ) ' > ,J. / i* *>1 ^ .1 % :> ;- "* +%. j' A j n l b t VAB.0001130603 Fortmvcunxort/ "FFCT" ON flUSVS- JOR <2c*?0/KSeT r l T&rr <1sia/ wits &*H uJ. A/o 4/s C Mu* 9WS &&.tT % Op Lo-C.fav' I fcQO ^ _____ I_____ 5 o u'TO-'Vitff flicns-EK ^ o<2/>ivAcft'tuw i V VAB.0001130604 * \ Resin METS-IR Values Comparison f 6415/LU 6415/DC Coon 30 Bordon 6415/W Waoh-AS RESIN TYPES I Low Clay Formula f 5385 Abd 5385 OKC A i K o/tSssyj VAB.0001130605 M o ts IK . (?J of* c o n t r o l ) 230 T 220 -j 210 A 200 190 _J 180 A t 170 160 H 150 140 -4 d 130 -! aa a a 120 110 100 -j ' 90 i 80 A 70 60 50 40 30 0 (Jt-XL i 4 Xfets IR AVG 111,7 Mets IR vs Sodium CV 9 1-hIII 6 n cn a #-- I 20 3 P I nn r 40 Sodium! (ppm) O N'a* AVG *-e ** * - .. 1 26.3 1 1 60 VAB.0001130606 pT V r u* /1 0 0 0 FT 35129 35137 35145 35154 35182 35170 35178 1LEN0 NUMBER 35186 35195 35203 35211 VAB.OOOl130607 ! SODIUM REACTOR SODIUM GAIN BY REACTOR 70 VAB.0001130608 Plant Comparison Wafer Sodium and METS~IR Oklahoma CHy IV 1 Water Sodium (ppm) Reeln Sodium (ppm) Abardoon Slurry Sodium (ppm) Lo-Ctoy METS-IR (X) VAB.0001130609 SODIUM (p p m ) 90 80 70 60 50 40 50 - 20 - Steem Effect (?) l\ [ Cold Water OKLA CITY \Z/ A Hot Water ABERDEEN Slurry Water f VAB.0001130610 r * f JKTAL OPTIONS RAW GORDO WATER Rfltf HKTER NUB MANGANESE QffiENSAK) IRON RQCNAL (pQ fi&ISBD FROM 7.5 TO aj_ ' ,, -- -*m _ SAME WITH BCW-90DIDH _BOFEER SAME WITH SODIUM BUFFER WEST POINP TREATED WATER (030, JMJM' Q) BUFFER AND RECIPE WATER BAWLING BQUIEMENP + _ HOCKDPS AH) CS&BQL EBOCHXJKE _ ^SAMPLES ANQAffiLYSIS RESIN DISPOSITION FUNDING Vh DRAFT PROPOSAL FOR PLANT TRIAL TO BE READS' BY OCTOBER 22 , I i \ f I r i i 9 i VAB.0001130612 BLEND NUMBER TAfiLB A Data accordingto 4 H" -^tSr-v*- r> A > +j*-< %* *. % If L*"b_^. #T* 5 --f p.r v,4' r. .ii sJi**- t "' 'i y A i - - ^ . j " If^1 v;iT j. ; V\ L ' '' - p-fr'-T i1 1 r pa _ #" ** : * - J ** .. * .< ; r * -* ' '' . . ^:. t-/* I - I*W V '; r * -f > SB?*'"" *C ' ^ >^J ^ 'i / j- ,L.a < , h ' M -- l <- Hi ' - f*1' .'- *- \. ..-.l -* 46477 AVERAGE BLEND NOMBER 46449 46472 46481 46483 46489 46497 46501 46511 METS tR NETS IR BEFORE WASHING i AFTER WASHING 144 221 157 179 -> y A *k a 1* J 7' * .rC,,' * ' t^'.i & 4- A >*>* 1*. V '-O.h 18B 1- r.T*- m*. 157 v ISO .i >*iC m : *- .A%. ' vs M S*1 . V ' **V ,Pi ,H.` ** ! v*r *X .* v- nib - V - V? *w^' *V AVERAGE 83.4 172.1 I decrease infsodium concentration) t o A'*' s*~. V -v * *. f' ft j , ^ -' **'" - ' " '+-tj*-._ i-4 l' F*' r,*- - L .1- 1 r ?V*-" #fc * * iA ! .$& * a y -+- V 'L^-' - rv * f ** <. k, ' '" ;v^Svb * 'I'.L >f J|--h * "*4V.L Jt< \ (106%4% increase in METS IR value) VAB.0001130613 A INSULATION RESISTANCE (2) PRIMARY SUSP AGENT VARIATION OF INSULATION RESISTANCE WITH SECONDARY SUSPENDING AGENT SORBITAN ESTER BRAND A HALF-LOAD PVA SECONDARY SORBITAN ESTER BRAND A FULL--LOAD - SORBITAN ESTER BRAND B A FULL v half 140 135 o 120 * $ 100 Q. *I 1 , -A T4 4 J v"- i-A * hX ^ Vt * 1%V 80 A . **; A i.<;p*1 . 1-V A 4 97 O V T . -*v ^r I > % VAB.0001130614 0001130615 i mmmrnmmmmmmmmm wmmmmmm R\(blO PVC. wmmm VAB.0001130616 RIGID PTC TRAINING MANUAL Table of Contents Formulating Rigid PVC: Stabilizers ..................................................................................... Processing Aids .......................................................................... Impact Modifiers.......................................................................... Pigments. ... .......................................................................... Fillers ................................................................................................ Lubricants........................................................................................... Physical Forms of RPVC: Dryblend versus Pellet Cell Classification of Rigid PVC .................................. Mixing Rigid PVC.............................................................. Rigid PVC Applications: PVC Pipe................................................................................................ Injection Molded Applications for Rigid PVC Regulatory Agencies: NSF and PPI . . . . . Rigid PVC Sheet .......................................................................... Vinyl Siding. ............................................................................... Profiles................................................................................................ .1 .4 .4 .5 .6 .7 .9 .10 .12 .16 .21 .24 .27 .29 .30 VAB.0001130617 A POfjMULATIHG RIGID PVC With many thermoplastic polymers, it is necessary to add only small amounts of a few additives to obtain satisfactory properties for fabrication and physical properties. PVC, on the other hand, requires significant portions of additives. Without these additives, the properties of the PVC resin would be unsuitable for fabrication operations, such as extrusion; and the end-use proper ties of a fabricated article would also be unsatisfactory. This has resulted in a significant amount of technology on PVC additives and a substantial industry to supply this market. A benefit of PVC, with regard to additives, is the wide variation in properties that can be obtained depending on the type and amount of additives used. The stiffness of the PVC can be varied from very rigid items like PVC pipe to very flexible items like weather stripping or gasketing. Similarly, other properties can be widely varied with the same basic PVC resin by changing the additive package employed. In flexible PVC compounds, the major consideration in selecting additives is their effect on the physical properties of the fabricated article, such as hardness. With rigid PVC, on the other hand, more consideration must be given to the effect of additives on the processing of the compound. This is due to the high melt viscosity of rigid PVC relative to flexible PVC, and the resultant greater tendency for thermal degradation and poor melt flow. Typical rigid PVC formulations will contain from 93% to 75% PVC resin, with the remainder being additives. A typical rigid PVC formulation might contain seven (7) ingredients in addition to the PVC resin. Based on their function, these additives can be classified into various categories which we will discuss below. Stabilizers Without the addition of heat stabilizers to PVC, subsequent processing and fabrication operations would be virtually impos sible. PVC is much more heat sensitive than most thermoplastics. Exposure of PVC to heat causes decomposition of the polymer. This involves both chain scission (breaking) and cross-linking between polymer chains. This thermal degradation can occur even at relatively low temperatures, such as in the intensive mixing step of dryblend preparation. Thus, it is necessary to add thermal stabilizers to PVC before any mixing or fabrication operations are carried out. In addition to decomposition of PVC due to thermal energy, ultra violet (uv) light exposure causes PVC degradation in a similar VAB.0001130618 f fashion. Stabilizers also play an important role in minimizing ultraviolet light degradation of PVC. Even with the use of the best additives, neither thermal degradation nor uv degradation can be totally prevented; but the amount of degradation can be mini mized to the extent that the useful properties of the polymer are maintained. The decomposition of PVC due to either thermal or light degradation results in several changces in the properties of a PVC compound. These changes include an increase in the melt viscosity with resultant changes in the processing characteristics; changes in physical properties such as increased stiffness, increased brittleness, and generally lower strength characteristics; and discoloration. The change in color is the symptom of thermal degradation that is generally noticed first by a PVC processor. This color change initially is a yellowing of clear or lightcolored PVC, becoming progressively brown or greenish-gray degradation continues. Eventually, the polymer will turn black. This color change is accompanied by an increased tendency of the PVC compound to stick to the metal surfaces of the processing equipment. This combination of changes can result in a somewhat catastrophic situation when degradation problems occur during processing operations. Once a PVC compound begins to degrade, the auto-catalytic degradation is accompanied by evolution of hydro chloric acid which is irritating to the equipment operators and can result in corrosion of processing equipment. A typical result of severe degradation is etching or chrome removal from processing tooling due to HC1 evolution. The sticking tendency of degraded PVC contributes to the problem because it is more difficult to remove the degrading PVC from the metal tooling surface. Since the HC1 evolution of degrading PVC further catalyzes the degrada tion process, a small area of degradation in an extrusion die, for example, can rapidly lead to degradation throughout the die with potential economic losses due to damage to the metal Thus, it is apparent that adequate stabilization of rigid PVC compounds is important. However, the tin compounds which commonly used as stabilizers in the United States are relatively expensive compared to other PVC additives. Thus, the formulator must strike a balance between adequate stabilization and minimal stabilizer costs. J Various t*st methods are used in the laboratory to intentionally cause thermal degradation of a compound for purposes of stabilizer evaluation and a determination of the appropriate degree of heat stability required. Generally, these tests can be classified in two categories. Since the color change of degrading PVC is the symptom most obvious to a PVC customer, a common type of stability test is to measure the color change of a test compound on exposure to heat for varying time periods. Another common test involves measurement of the rheology changes that occur with degradation of PVC. This is most commonly done with a torque rheometer and is the method Vista uses for quality control of thermal stability for our dryblend products. 2 t VAB.0001130619 In selecting a stablizer type and amount for a rigid PVC formula tion, various factors must be considered. Thermal stability and cost are most important. The fabrication process and end-use often determine whether a color stability test or a torque rheometer stability test is best suited. Stabilizers in liquid form can decrease the maximum end-use temperature of the PVC compound, since liquids have a plasticizing effect in rigid PVC formulations. Most stabilizers also have some weak lubricant action, and the lubricity contribution of the stabilizer must be considered to insure adequate processing. In applications requir ing outdoor weathering of the fabricated article, the light stability characteristics of the stabilizer must be considered. The toxicity of the stabilizer must be considered, primarily with respect to extraction of PVC compound ingredients in food contact or potable water applications, but also with respect to worker exposure to dusts from PVC dryblend which may contain heavy metals. In some applications, such as food packaging, the odor characteristics of the stabilizer should be considered, particu larly since most stabilizers used for rigid PVC in the United States have disagreeable sulfur odors. Each of these character istics should be considered when selecting a stabilizer for a rigid PVC formulation. The vast majority of stabilizers used in rigid PVC in the United States sulfur). tin mercaptides (organo tin compounds containing In Europe, it is customary in many applications to use barium cadmium compounds or lead compounds to stabilize rigid PVC. However, these two stabilizer types are not often used for rigid PVC in the United States, primarily due to toxicity concerns with such heavy metals. In a few applications, other stabilizer types are used in the United States such as calcium zinc compounds in food applications where tin mercaptides result in odor problems, or non-sulfur tin compounds (carboxylates) where weathering properties are particularly important. In general, though, the vast majority of rigid PVC compounds contain tin mercaptide stabilizers in the United States. These stabilizers typically range in price from $2.00 to $4.00 per pound and are used at concentrations of 0.3 to 2.5 weight percent. Nearly all tin mercaptide stabilizers are liquid; these are often the only liquid components used in rigid PVC formulations in the United States. The major U.S. suppliers of tin stabilizers are M & T Chemicals, Argus, and Carstab. Also available are "package stabilizers" which are-*combinations of tin mercaptide stabilizer plus various lubricants. The advantage of these additives is a reduced number of ingredients which the compounder must add to his PVC resin. Antimony mercaptides have taken some share of the PVC pipe stabilizer market from tin stabilizers due to lower cost. Perfor mance is similar to low-strength tin stabilizers except for lubricity characteristics. The major supplier of antimony stabilizers is Synthetic Products (Synpro). A VAB.0001130620 ii Processing Aids Processing aids are additives which assist in the fabrication of PVC by processes such as extrusion or injection molding. Process ing aids generally have no direct effect on the physical proper ties of the finished compound, such as impact strength, but can have an indirect effect on physical properties by assisting processing, such as through more complete fusion. Processing aids perform several functions to assist fabrication. A primary benefit is that processing aids promote fusion of PVC resin. Other beneficial functions include reducing plate-out, increasing the "hot strength" of the PVC melt, improved thermoforming characteristics, and improving surface appearance of injectionmolded articles. Without processing aids in injection-molded rigid PVC, appearance defects known as splay and blush are likely to occur. As a result of these beneficial characteristics, processing aids are used in most rigid PVC applications in the United States. The major exception to this is PVC pipe. Due to the importance of low formulation costs for PVC pipe, processing aids are generally not used on twin-screw extruders. This makes processing more diffi cult; but, with care, good results are obtained. The processing aids most often used are acrylic co--polymers. These are high molecular weight powdered polymers. The more common grades cost approximately $1.20 per pound and are commonly used at 0.5 to 3% concentration. The major U.S. ssuuDppDlliieerr of acrylic processing aids is Rohm & Haas Company, with M & T Chemicals and Kaneka as minor suppliers. 4 Impact Modifiers Impact modifiers are rubbery polymers which are compatible with PVC. Addition of these rubbery polymers increases the impact strength of rigid PVC and causes breakage to be more ductile in nature. This improved "toughness" is critical in some applica tions for rigid PVC but is unnecessary in other applications. A major market where impact modifiers are not needed is in PVC pipe. Most other rigid PVC applications use impact modifiers to some degree tcTincrease impact resistance. The improvement in impact strength of the rigid PVC as a result of impact modifiers is particularly pronounced at low temperatures. Due to the high amounts of impact modifiers required in some circumstances, and the relatively high cost of such modifiers, the rigid PVC forraulator must use only the minimum quantity of impact modifier required. An additional reason for minimizing use-levels is the generally detrimental effect of impact modifiers on processing characteristics. Impact modifiers generally increase 4 VAB.0001130621