Document DGJDa2RNvqgjvEaNKaYDpgR2O

The information contained in mis bulletin is believed to be accurate, but all recommendations or suggestions are made without guarantee, and there is no implied warranty of merchantability or fitness for purpose of the product or products described herein. In submitting this information no liability is assumed, or license or'other rights' express or implied given with respect to any existing or pending patent, patentapplications or trademarks. COLORITE 007256 880 Johnson Ferry Rd. N.E., Atlanta, Ga. 30342.......... .(404)252-5150 5366 North Elston Ave., Chicago, II. 60730................. .(312)^86-5333 1330 Center Ridge Rd., Cleveland, Oh. 44116............. .(216) 333-3877 P.O. Box 40, Fords, NJ 08861..______________ ____ .(201) 826-2300 1433 West Loop S., Suite 406, Houston, Tx. 77627 .. .(713) 626-4610 300 Needham Street, Newton Upper Falls, Ma. 02164 . .(617) 969-6000 6600 Artesia Blvd., Buena Park, Ca. 90620____ ...... .(714) 994-3481 Tenneco Chemicals . ATannaco Company Polymers * Reg TM of Tenneco Chemicals - Reg TM of Tenneco Inc -5000 '(U: JW?' `' ^ - ^. J 'V VV ^ ^^ ^ ' ^ ' ' ' :,' L,i " ' " . ' ' - ' : ,^v : '"v; '- ^ ';r - v.,' X COLORITE 007257 Cover R. T Martmott contents Seep H TOP OF THE NEWS 11 Lead phase-down in gasoline poses threat to key petrochemical feedstocks. 13 Mississippi proposes phase-out of mirex production and use by mid-1978. 14 Goodrich. Uniroyal reach agreements with URW ending nearly five-months-old strike. 15 Vaccine makers, claiming production is at full capacity, balk at call for speedup. 16 Chemical and allied products job tally rose 0.1% in August, says Labor Dept. 16 American Enka expects to have third-quar ter loss, reports Akzona. INTERNATIONAL 23 Sweden's nuclear energy development plans challenged m national elections. MARKETING 34 jstrong PVC markets are spawning major ^^texpansions in resin, monomer capacity. 39 jVinings Chemical tackles international ^market with specialties for papermaking. 4 TECHNOLOGY 43 European companies making strides in the development of polyolefin synthetic paper. 51 New system uses treated waste stream to fertilize crops and attract industry. PEOPLE 56 New York State's Werthamer is making the switch from scientist to bureaucrat. Coming in CW Fluidized-bed combustion: prom ising new way to tap energy from coal. CW, Sept. 22. Petrochemical feedstocks, except propane and butane, are being decontrolled by FEA. CW, Sept. 22. Departments Business Newsletter.................... 9 CAPS........................................... 48 CW Business Indexes................33 Environment....................... 51 International............................. 23 International Newsletter......... 21 Key Changes............................. 55 Market Newsletter................... .33 Markets...................................... 34 Meetings.......................................5 People.........................................56 Reasearch..................................43 Specialties.................................. 39 Stock Market Report................. 19 Technology Newsletter............ 47 Top of the News.........................11 Washington Newsletter............ 10 % I a Cn****c* Wimik (.nchnSng S{We*6b and CtsevTXil Indus(mu) <i pyCmNso i i ty py McOraw He* IAC 1221 of fr# ArrmrtQtt. York, N Y 10OZJ Fr*jr>On Janwe H >AtGr-i <ldo0l9*Adj T<0* reyntwwt H)S Parent 0tw;* (Cl Cooyntfit 1976 07 AcOy.Miii Ir'C. 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Of rs^t any sotf* cah*n Unconditional QuaranW Trte p^teuhe"', U0V* wcrtrie* 'njoast fi-C>m any sii^aqritMr ayrem b ralynd On o*rt at *A*b'Ofw pne* apSlyirwj tn s>--s not >et Wnd a? ert<*ind*<# lutoCnpnon including addrwa ClWQt f Mwmml CrtSnacjf Vi^rfi p O dTM >LAl H^ntatman. N 1 OdsM Nofify Fuffi*f*jnt Manw^ar oerwroar of any oyn)* of adtmna. new addree* w>m no CizSa and ooataf im ivw and inctsd* a " hjwng qtd MCreis AWwim. eqrm Nsr ehanO* W1* `f'-'f"* feitiwht Pte^e ml Fjiiii 1)71 t> fyWaeH Mbit**, WmA. Fata* 4J*A N.X QfUdL Osoy;af > puty-sneF he, van. wiionH st*H md * l?2lm>n>ga*vw\ oOnf*O>0dWiitWnlfotnuJfy ijrtmfjabmvaaa.t OI"w* nWrfa - * 11 970. Tinsw* Vear iia*sm, Yory, ft Y 1Q0>* * K L COLORITE 007258 markets PVC rolls out of jeopardy, into jubilation Rapid resurgence of demand shows vinyls are still a bargain in big-volume end-use applications. Confident that growth will continue, producers boost outlays for monomer and polymer plants Strong demand for polyvinyl chloride in all major markets--especially pack aging and textile applications--is leading to new plant commitments and price hikes. Last week, for example, both Fire stone artd Tenneco unveiled plans to build new PVC units, each with capacity of 200 million lbs./year or more. Also last week, PPG joined other pro ducers in raising its vinyl chloride mono mer (VCM) price to 13.6<c/Ib.. a 1C incre ment equivalent to nearly 8%. Mean while, Diamond Shamrock added R to its tabs on PVC resins and molding com pounds. thereby boosting them to levels previously set by Goodrich. Pipe-grade resin is now quoted at 25e/lb., generalpurpose suspension homopolymer at 26c/lb. Clearly, those actions signify U.S. vinyl producers' confidence that they have solved the "OSHA problem" that threat ened the viability of their industry less than two years ago. They have installed the equipment needed to meet the worker-exposure requirements set by the Occupational Safety and Health Admin istration, but without inflating production costs to the point where PVC's growth might be stunted. No Shortage in Sight: PVC capacity doesn't appear to be a problem this year. The industry has polymerization capabil ity of nearly 6.4 billion lbs./year (see table), and its average operating rate dur ing first-half 1976 was about 73%. Even if producers find it difficult to hold the in dustry-wide average to more than 80% for an extended period, their potential out put would still exceed this year's pro jected consumption by nearly 500 million lbs. And with process improvements to increase effective capacity, producers be lieve they'll be able to meet the greater demand that now seems assured for next year. Furthermore, capacity for the mono mer won't be a problem in 1976. VCM producers have nameplate capacity for almost 6.8 billion lbs./year, easily enough to handle this year's probable demand of 5.5 billion lbs. VCM output was de pressed earlier this year when operating problems hit some plants, but those prob lems have been cleared up. And recent months brought an end to the chlorine shortage that materialized 34 CHEMICAL WEEK September 15, 1976 last spring when chlor-alkali producers lowered their output rates because they were turning out more co-product caustic soda than they could sell. When caustic markets perked up, chlorine output was boosted proportionately, enabling VCM producers to make the monomer at the rate of 6.2 billion lbs./year in June, com pared with their average rate of 5.2 bil lion lbs./year during the first five months. Lid on HI Output? Next year, though, VCM capacity could be the limiting fac tor in U.S. vinyl production. If monomer demand hits 5.5 billion lbs. this year and swells 10% m 1977, VCM producers will have to run their plants at about 85% of capacity to meet demand. That's about the upper limit for equipment utilization. USE OF PVC, as in Monsanto's rigid vinyl gutters (above), heads for new high in 1976. even assuming no plant mishaps. Borden's startup of a 300-million- Ibs./year plant at Geismar, La., will lift next year's total name-plate capacity to more than 7 billion lbs./year. Plant im provements may boost that figure slightly, but it's still unlikely that mono mer producers will be able to turn out more than 6.3 billion lbs in 1977. However, VCM capacity will take a bigger jump late next year when Dow brings onstream a l-biilion-lbs./year ad dition to its complex at Plaquemine, La. That should enable the industry to handle 1978 demand with ease. And if 1978 ushers in a business slowdown, as some economists have been predicting, U.S. capacity then will be more than ample. Name-plate capacity of fully 9 billion lbs./year, enough to handle anticipated 1979 demand for nearly 8 billion lbs. of the monomer, will be realized in 1978 when Diamond starts up its 1-billionIbs./year plant near La Porte. Tex. But if VCM demand keeps on growing at any thing like its long-term 12%/year rate during the 1980s, an additional 2 billion lbs./year of capacity will be required ev ery three years. On the other hand, some of the industry's more conservative mar ket researchers say vinyl's growth rate will drop off to 4-5%/year in the coming decade. Three Coming, One Going? At this point, it appears that there'll be three newcomers on the list of VCM producers during the next few years and that one present producer, Allied Chemical, may leave the dub. Allied has been discussing with several prospective buyers the pos sible sale of its 300-milllon-lbs./year plant near Geismar. One likely buyer Robintech, which up to now has had no captive monomer supply for its resin pro duction. Borden will begin producing VCM un der its own name late this year when the company's chemical division starts up its 300-million-lbs./year plant at Geismar. Borden currently gets up to 150 million lbs. of monomer each year through its 50% stake in Monochem, a Borden-Uniroyal joint venture that since 1962 has op erated a 300-million-lbs./year plant also located near Geismar. It's the only U.S. VCM plant still using acetylene, rather than ethylene, as feedstock. Borden's polymerization capability is now about 545 million lbs./year, so when the PVC units are running flat-out, Borden will still have to buy monomer at rates up to 100 million lbs./year. Biggest vertical integration move on the vinyl industry horizon will come about two years from now when Dia mond starts producing VCM in the 1-billion-lbs./year plant to be built at La Porte. It's a logical move for Diamond, whose chemical division has large PVC and chlorine plants at Deer Park, Tex., and whose oil and gas division will soon be supplying ethane that will be con verted to ethylene in Phillips Petroleum's olefins plant at Sweeny, Tex --all loca tions that are within 60 miles of the new COLORITE 007259 markets Few vinyl producers are fully integrated Air Products ^ Allied Chemical- ^ - T 4 .'t..-- Raw materials , . produced ,,,- >.V* *' V',-M Vinyl chloride capacity at mtd-19761 . (Million tb^/year) ' i > . Monorner -x '^'* '. Polymervj * 'vi.kWV9h.* "* - " t" 'l - Ethylene* chlorine: OUU .In joint-venture- fUNw rnonomer capacity.due-anatream^by 1978:-Bordnl 300 miUtonV ib*_; Diamond Shamro.c.k.,.! billion tbs..; Do.w,.1 billion l-b--s--...(..2..)..S...u...b...s..t.d. .i.j.r..y....D...f...O. ,,c..c..i.d..e..intatail PPsstrtoro--- V leum. *(3Uoint1y owned by Borden and .Uniroyal. Jnc. (4)Owned by Shin-Etsu > Chemical 4 Industry Co; (Tokyo!- -, . - vinyl monomer project at La Porte. Dow's new l-billion-Ibs, VCM unit un der construction at Plaquemine, slated for completion about one year from now, will raise that company's domestic capac ity to 2.4 billion Ibs./year and strengthen its position as tita^largest U S- producer. Along with Shell and PPG, two of the other three major VCM suppliers, Dow is strictly a merchant producer and likes it that way. While shunning forward inte gration into polymerization, Dow is sol idly integrated into the raw materials: it is No. 2 among U.S, producers of ethyl ene and is the world's No. I producer of chlorine Polymer Pinch Possible: PVC produc ers also will need more capacity in 1978 and beyond. Although they can probably meet next year's projected demand of 6 billion lbs. with their current capability plus improvements and expansions now 36 CHEMICAL WEEK September 15, 1976 under way, an additional 600 million lbs. of resin will be needed in 1978, assuming normal growth. A moderate economicdownturn in 1978 could shave that year's PVC growth to 57o or less, but markets are likely to be tight unless name-plate capacity is boosted to more than 7 billion lbs /year. Some half-dozen new units will come onstream during the next two years, but still more expansions will be needed. Pro spective PVC demand in 1979 and later years will require new capacity equiva lent to at least three new 200-millionlbs /year units each year. Those new plants, along with the nec essary capacity for VCM, will undoubt edly be built. And there will probably be periods of overcapacity. But PVC prices are sure to keep moving up. with only temporary interruptions. Reasons, on a unit-of-capacity basis, new plants for VCM and PVC alike will be much more expensive than those now in use. and feedstock costs are also headed upward Plants Get Bigger and Better Even during the dark days of 1974-1975 when stringent new safety standards were being drafted for their plants and when the plastics industry was taking an especially severe mauling from the worst recession since the 1930s, PVC makers went ahead with costly construction programs. Last year they added close to I billion lbs./year of net capacity. And they're continuing to spend large sums to im prove existing operations and build new units. Goodrich, the largest PVC producer, in winding up an expansion in Louisville, K.y,, whose main feature is a 250-millionIbs./year polymerization plant with strip ping column technology that it is offering for license to other producers. Goodyear says it's spending "several million dollars" to install Rhone-Poulenc's "microsuspension" polymerization process in its plant at Niagara Falls. N.Y. According to Goodyear, that will be the first use of that technology in the U.S. The unit is rated at 50 million lbs./year. Union Carbide, whose PVC capacity now stands at 400 million Ibs./year, has sold its dispersion resins business to Stauffer and will shut down the 50-million-lbs./year dispersions plant at South Charleston, W.Va. That cutback, how ever, will be offset by debottlenecking of its plants for other types of resins, and further PVC expansion is on the drawing board. Also debottlenecking is Georgia-Pa cific, which thereby hopes to add mod estly to its 220-miilion-lbs./year capacity at Plaquemine. New Units Coming: Aside from those modernization projects, at least eight companies are building new PVC units. Two or those expansions will be at Dela ware City. Del.; and both are for disper sion resins, sometimes called plastisols. Stauffer is adding an 80-million-Ibs./year unit, due onstream within the next few months. And just last week. Diamond's board of directors authorized construc tion of a 24-million-lbs /year plant at that company's Delaware City complex. The new dispersions unit is scheduled for completion in first-quarter 1978. At Calvert City, K,y , Air Products is boosting its capacity to 270 million Ibs./year. up 35% from the present level there, and plans to add 50 million lbs./year of PVC capacity at Pensacola. Fla., by the end of 1977. Robintech. which now has a 250-mil- COLORITE 007260 markets linn-lbs./year polymer plant at Painesville, O-. will raise its capacity to 300 mil lion lbs /sear by mid-1977 and to a hefty 500 million by the end of 1979. Shintech, formerly half-owned by Robmtech but now wholly owned by Japan's Shin-Etsu. is adding 5057 to the 220-millionIbs./year capacity of its PVC plant near Freeport. Te\., with startup slated for mid-1977. Gulf Coast Favored: Another company selecting a Gulf Coast state for its PVC expansion is Continental Oil. whose chemicals division will add about 165 million Ibs./year to the capacity rating of its plan! at Aberdeen, Miss. That will hoist Conoco's company-wide capacity lo 560 million Ibs./year in 1978. And last week Tenneco Chemicals said it will move ahead on its plan to build an approximately 200-million-lbs./year PVC unit in its complex at Pasadena, Tex. That project, scheduled for completion in mid-1978, will raise Tenneco's total ca pacity to more than 700 million Ibs./year. Tenneco's move came on the heels of Firestone's decision to build a new plant at a yet unidentified location by mid1979. That unit, says the company, will have a polymerization capacity of more than 200 million Ibs./year, advancing Firestone's domestic total--now about 400 million Ibs./year--to a level the com pany describes as "well above 600 million Ibs./year.'' Solid Rebound: All of those expansions seem to be well warranted, judging by the robust recovery in virtually all PVC mar kets so far this year. First-half 1976 data from the Society of the Plastics Industry show that PVC shipments climbed to 2.35 billion lbs., up almost 52% from last year's first-half volume. At that rate, this year's total shipments are likely to come close to the 4.73-billion-lbs. record high attained in 1973. Domestic shipments in this year's first six months rose 50,9% to 2,24 billion lbs., while exports mounted 163% to 110 mil lion lbs. Plastic pipe markets, the largest single outlet for PVC, look about 696 million lbs. in the first half, or about 31% of all domestic shipments. Deliveries to pipe fabricators were up about 50% from yearago levels, and at the current rate will reach a 12-momh total of 1.4 billion lbs. Upbeat Forecasts: This year's rebound is evidence that PVC markets still have a good deal of growth potential. And pro ducers are confident that the uptrend will continue next year. For example, Gerard F. Cohan, a Goodrich product manager for PVC resins, is forecasting that de mand will regain its 1974 level this year and thereafter will grow at about 11%/year. More bearish market special ists say not to count on a growth rate of much more than 5%/year. In support of the more optimistic pro jections, producers point out that percapita use of PVC in the U.S, is less than in other developed nations. It's less than half the pounds/consumer ration in West Germany, and somewhat less than the Japanese average. One key to PVC's prospects is its adaptability. By judicious formulation with plasticizers and other chemical addi tives, PVC resins can be used to make a wide range of end products, for homes and autos and apparel, with widely vary ing rigidity and other properties. Recent investment authorizations demonstrate a firm belief that fabricators will continue to find PVC an unbeatable bargain in hundreds of applications for many years ahead. PVC market growth accelerates c (Billion pounds) Apparel Conduit, pipe and fittings -Flooring ... - Siding, other construction applications Home furnishings Wire and cable Packaging Records Transportation ; Other Totals Source: fi.F. Goodtich Chemical Co. 1970 0.18 0.48 0.32 0.20 0.51 0.42 0.27 0.14 0.22 0.24 2.98 - 1975 0.18 0.99 -Cl.29 0.27 0.43 0.28 0.29 0.13 0.16 0.57 3.59 19B0 0.28 2.20 0.56 0.71 0.71 0.500.42 0.22 0.36 1.14 7.10 Rhodia Inc Chemicals Division PO Box 1?5 Monmouth Junction New Jersey-06852 (USA) Telex 844-527 rhone-poulenc tc^ -e c 21, rgp Jpan Gcujon 75^60 Pans Cede* 08 (Francet September 15. 1976 CHEMICAL WfEK 37 COLORITE 007261 Thermal Decomposition of Azobisformamide in High-Density Polyethylene and Poly (vinyl chloride) Frederick R. Wight Bell Telephone Laboratories, Inc., Norcross, Georgia 30071 The thermal decomposition of the chemical blowing agent azobisformamide (ABFA) in high density polyethylene and poly(vinyl chloride) was investigated. The effect of silica modifier in HDPE and lead and tin activator/stabiliz ers in PVC on the yield and composition of the gaseous products was determined. It was found that in addition to reducing the decomposition temperature of ABFA, silica and lead cause a significant increase in the yield of gas produced. Tin also reduces the decomposition temperature, but does not substantially increase the gas yield. All three additives were found to cause a similar and significant change in the distribution of gaseous prod ucts produced; most noticeably the carbon monoxide yield is reduced while the yields of ammonia and carbon dioxide are increased. A common mechanism is proposed to account for the effect of these additives. Introduction Azobisformamide (ABFA) (azodicarbonamide) is one of the most versatile and widely used chemical blowing agents on the market today. Its thermal properties, high gas yield, and low cost make it the choice for such polymers as poly ethylene, polypropylene, ABS, polystyrene, and others. Fur thermore, Lally (1967) has shown that the decomposition temperature of ABFA can be lowered by the use of certain "activators" such as lead or tin salts, enabling its use in polymers such as PVC and EVA. In addition, azobisfor mamide can be modified (MABFA) by the addition of 30-35% silica. The silica is said to reduce the concentration of cyarmric acid in the blowing agent residue and thus reduce plate-out which tends to build up on plastics tooling. LaClair (1976) has outlined several areas where ABFA and MABFA have useful applications. 00 H-N--C--'N=.V--C--NH, ABFA Relatively little exists in the literature on the chemistry of azobisformamide in polymer systems. Independent work by Reed (1969) and by Saunders and Hansen (1972) has been widely referenced on the mechanism of ABFA decomposition. Scheme I is the mechanism put forth by Reed (1969) for the decomposition of ABFA in mineral oil where biurea, urazole, and cyanuric acid are the principal residues, and nitrogen and carbon monoxide are the principal gases produced. Ammonia and carbon dioxide are produced to a lesser extent. The mechanism for the activated decomposition of ABFA by compounds such as tribasic lead sulfate has been postulated by Nass (1963) to involve a basic hydrolysis of ABFA to pro- Scheme I o (I) ABFA , I to * (HjN-C-NM2 iE HOCN + NH3| (21 2 ABFA H3 N_C-NH-NH-C-NHj * 2HOCN + Nj BIUREA | \ HN-NH ,=c > OH NN ) A-A oh URAZOLE CYANURIC ACiD Scheme II o 0 - H->0 N'^Ss`0' VABfA + Pb + * Bat* 2NH3 + w(I o' Pb + J o { N2 + CO + PbC03 duce an azodicarboxylate, which readily decomposes to ni trogen, carbon monoxide and metal carbonate (Scheme II). One aspect of the decomposition process which has not been reported but which is of importance not only in interpreting the mechanism of decomposition but is of practical impor tance as well is the yield and composition of gases produced by decomposition of ABFA in the presence of activators and modifiers. Reed (1969) reported the gaseous yield from ABFA as 220 cm3/g(STP) consisting of 62% nitrogen, 35% carbon monoxide, and 3% of a mixture of carbon dioxide and am monia. LaClair (1976) has indicated that MABFA also pro duces gas yields in excess of 200 cm3/g. We have investigated the yield and composition of gases produced by modified and activated ABFA in a polymer matrix and our results bear di rectly on the mechanism of ABFA decomposition. Experimental Section The gas evolution of ABFA and MABFA consisting of 66% ABFA and 34% silica was measured in high-density polyeth ylene (HDPE) at a concentration of 0.85%. Additionally, the gas evolution of ABFA at a concentration of 0.5% was mea sured in a semirigid PVC formulation containing 7.0 phr tri basic lead sulfate stabilizer/activator or 3.0 phr of the dibutyl tin type stabilizer/activator di-n-butyltin bis(n-dodecylmercaptide). The blowing agent was compounded into HDPE by means of a two-roll mill whereas the PVC formulation was dry blended in a high-speed mixer. Gas yields were deter mined by placing a weighed sample of each material in a small tube which was attached to a vacuum pump and mercury manometer. After evacuating the system to a pressure of ca. 0.1 Torr, the pump was closed off, the sample tube was heated to the desired temperature in a thermostated oil bath, and the pressure change was measured with time until no further gas had evolved. The sample was then cooled to room temperature and the final pressure was recorded. No changes were observed in the pressure on standing for extended periods, indicating the evolved gases were stable to the conditions of the appa ratus. The vacuum system was calibrated as follows. Neat InH Frtn f!hrn PnnHam VMt Mrv A 1077 aftl COLORITE 007262 Table I- Gas Yields from ABFA Expandable Polymers Polymer composition Polymer, cmVg ABFA, cm3/g 0.85% ABFA/HDPE 0.85% MABFA/HDPE 0.5% ABFA/PVC/Pba 0.5% ABFA/PVC/Sn* 1.68 1.48 1.70 1.03 197 264 340 206 " Semirigid PVC stabilized with 7.0 phr tribasic lead sulfate. 6 Semirigid PVC stabilized with 3,0 phr di-n-butyl tin bis(ndodecylmercaptide). Table II. Gaseous Composition from ABFA Expandable Polymers ____ cm3 of gas/g of ABFA (%) ' <'C| Figure 1. Gas evolution from ABFA and MABFA expandable poly ethylene and polylvinyl chloride). Heating rate, 5 C/min. ABFA was decomposed at atmospheric pressure by connect ing the sample tube to a gas buret and mercury leveling bulb. An identical quantity of neat ABFA was then decomposed in the apparatus under vacuum. The volume of gas evolved in the first measurement was then correlated to the pressure change observed in the second run. All samples were recorded in triplicate and the data presented here represent the average of the three runs. Results and Discussion The degree of activation of ABFA can be seen in the curves in Figure 1, which were obtained by heating the samples under vacuum at approximately 5 C/min up to the temperature indicated by the termination of each curve. Heating beyond this point was not attempted due to the onset of polymer degradation at these temperatures. The gas yields shown are uncorrected for the change in pressure produced by the in creasing temperature. The lead stabilizer in PVC can be seen to have the strongest activating effect followed by the tin stabilizer. Note that silica in MABFA also appears to have a slight activating effect on the decomposition of ABFA. Table I shows the room temperature gas yields obtained from each of the compounds. Note that silica and even more significantly lead produce an increase in the total gas yield in cm3/g of ABFA. Tin appears to have a negligible effect on the total gas yield, however. As a consequence, less ABFA is re quired in lead stabilized PVC compounds vs. tin stabilized PVC to achieve comparable expansion. Finally, Table II shows the composition of the gases evolved from each sample. The presence of silica in HDPE or lead in PVC was found to increase the nitrogen yield, while tin had no apparent effect. Except for lead, there is a decrease in the carbon monoxide yield, but most apparent is the fact that significant inert ases in the carbon dioxide and ammonia yields are observed in the presence of all three additives. The close similarities in the changes in the gaseous yield and composition produced by the three activators suggest a common mechanism by which each of these compounds in teracts with ABFA. However, Scheme II {which incidentally requires thermodynamically less stable cis configuration of 482 Ind. Eng. Chem., Fundam.. Vol. 16, No. 4, 1977 Sample N2 CO C02 NH, ABFA/ HDPE MABFA/ HDPE ABFA/PVC/ Pb ABFA/PVC/ Sn 121.9 (61.9) 69.0 (35.0) 145.1 (56.1) 47.5 (18.0) 153.4 (45.1) 71.7 (21.1) 121.1 (58.5) 56.7 (27.4) 3.9 (2.0) 58.3 (22.0) 83.3 (24.5) 22.6 (10.9) 2.2 (U) 10.3 (3.9) 31.6 (9.3) 6.6 (3.2) ABFA) is clearly not consistent with the data presented here. If Scheme II were a significant pathway to decomposition of ABFA, the carbon monoxide yield would be expected to in crease significantly while the carbon dioxide yield would be expected to remain quite small. An alternative mechanism, more consistent with the observed results, would be the cat alytic hydrolysis of one amide function by the activator to give ammonia, followed by rapid decarboxylation to give nitrogen and carbon dioxide (Scheme III). It is quite likely that this is Scheme III ABEA a -= CAT Oo n ii NHj*H,N-C-N=N.C-0_ J7 O* II RESIDUES + GASES-*-- HjN-C" + Nj + COj not the sole pathway to the decomposition of ABFA. In all probability, a combination of free radical and ionic pathways is contributing to the decomposition of ABFA. Summary and Conclusions The decomposition of azobisformamide in HDPE and PVC has been investigated. Results show that modifiers or acti vators, such as silica and lead or tin salts, in addition to re ducing the decomposition temperature of ABFA, also increase the gas yield and alter the composition of the gases produced. The similarities in the changes in the gaseous composition produced by each additive suggest that a common mechanism occurs with the presence of each activator. The mechanism proposed involves catalytic hydrolysis of one amide function of ABFA to yield ammonia and a species which decarboxylates to produce nitrogen and carbon dioxide as the principal gases. Literature Cited LaClair, R. C.. Plast Techno/.. 31 (Mar 1976) Lally.R E,, Alter, L M.. SPEJ,, 23 (11). 69(1967). Mass, L. I.. Mad. Plast, 40 (7), 151 (Mar 1963) Reed, R. A., 8m. Plast, 33 (10). 469 (1969) Saunders, J. H , Hansen, R. H . in ''Plastic Foams." Vol. I, p 23, K. C. Frisch anO J H, Saunders. Ed , Marcel Dekker, New York. N.Y.. 1972. Received for review February 14,1977 Accepted July 1,1977 COLORITE 007263 Key Polymers Polyvinyl chloride - CM -CH Cl Demand good Capacity rising Pricing unstable PRODUCTION/CAPACITY c HOW MADE tree radical polymeric,P'cn of vinyl chloride using an initiator such as a petoxtde MAJOR FABRICATED FORMS Pipe and httmc1- do1), , fum- one sheet 75V,', floor mg mat: rials I0r wire and cable insulation 5 V. , au\>motive parts 5h . adnesivf's L,nd iodines 5% FOREIGN TRADE Exports--declining this year to about 250 million Id or loss, imports -- negligible PRICES 25 to 27 cents a lb. dependmu on type, with dr-.^ou.nts COMMERCIAL VALUE $ 7 5 billion for total production. 1978 Polyvinyl chloride will have a good year in 1978, probably better than next year U S production will be up nearly 8% in 1978 over 1977 Selling prices gen-rally have firmed and are likely to go up although pricing has been a se ries of ups and downs with a real trend difficult to discern Plant capacity ex pansions cire beginning again, too As with many other chemical prod ucts, demand for polyvinyl chloride boomed surprisingly as the second quarter unfolded Price increases soon Came along PVC producers began pushing to meet demand without letting inventories of certain kinds of resins get out of line This upsurge led to optimistic forecasts by some PVC producers that there might even be a 10% production gain for the year The summer doldrums strived to temper this optimism and bring price discounts midway through the third quarter Current thinking as a result is that a further slacking is due in demand growth later in the year, One forecast is that 1979 demand growth will be in the 5 to 7% range There ate predictions tnat price increases will be rriade before year's end that will hold into 1979 unless the e-Onomy falters badly Part of the reason for differences in opinion on PVC's future comes from PVC's consumption pattern Alone among the big thermoplastics. PVC has markets dominated by durable uses Some of these uses have, cycles somewhat different from the main business cycle A big part, now estimated at more than a third of all domestic U S con sumption ot PVC, goe-- to make pipe and fittings Most of those fabricated prod' ucts qo into housing Other large vol umes go into agriculture as irrigation pipe and into uonduit for electric power and telephone cables Except for the irrigation outlet, much of the market for pipe? resins depends on how well home, apartment, and com mercial construction goes So far this vear. some choppiness has shown up in the high level of housing demand, but even soaring interest rates haven't dampened demand much vet This de mand alone keeps PVC pipe moving w e 11 Currently, the majority of PVC pipe and conduit carries either wastewater, vent gases, or cables, Changes in building codes provide qood increases for these uses alone However, increased future use ot PVC pipe in carrying potable water could keep demand for the pipe on a strongly rising cuive Estimates of the market penetration potential for this use vary widely but are very large On balance, it appears that the shift to PVC pipe for water supplies in housing and com mercial buildings will continue over a long period, a cT-cade or more This shift will provide substantial outlets tor PVC production capacity not yet on the drawing boards This new area, plus PVC use in conduit, some industrial piping and dram waste, and vent piping should make the share of PVC going to pipe ever larger Unfortunate!) the other mam uses of PVC care not having such a strong year Most such as film and sheet including automotive uses, have much lower G'Owlh rates Tne reason is that much of the potential market penetration has been necompi'Shed In some instances of automotive uses, such as 'vinyl tops," demand actually has disappeared uruRr the vagaries of consumer fashion oesees Other housing-related uses of PVC also have slackened their grov* tn rates because ot changing fashion furniture uses of films are now t ismg very slowK if at all Flooring, even with good de velopment hi ro!i forms in addition to tile, has settled into a low growth rate The vinyl aiding market is cited by some industry sources as the next ' pipe" market in growth for PVC As yet vmvl siding takes a relatively small share of PVC consumption However, this use could grow rapidly as did the pipe and conduit market when these caught hold attm long charts to gam acceptance from building authorities Estimates are mat use of PVC for siding could reach 200 million lo in 1980, double the 1977 use of under ", 00 million Id Producers ,j'so are coping with pric ing problems by shifting to larger reac tors particularly for suspension poly merisation, and to computer control to gam uniformity and production cost saving* The --rrger reactors for which computer control can be justified could cause a smft to larger capacity plants In this case, many of the smaller units could he shut mown Hence, pientv of change may yet be due tor PVC, an old-line polymer Cur rent trends m ise for a good 1978, a slightly slowe' 1979 and some big new markets later 'V i, r, . - o / h rrrj -t'i COLORITE 007264