Document jNg9O0bpmgK5YNKDODBnEKrOR

R&SI 68022 TOOT-VV------ * * * * > * * 1U U7SU THE DOW CHEMICAL COMPANY Abbott Road Buildings, Midland I TECHNICAL SERVICE AND DEVELOPMENT____________________________ Schober, A, E. AA-1001 11-28-58 EVALUATION OF VINYL CHLORIDE AS A PROPELLANT FOR AEROSOL PAINT A propellant system comprised of 80# vinyl chloride and 20# pro pane performs satisfactorily in aerosol paints. Flammability of a paint system containing this system is very similar to current commercial formulations. Polymerization of vinyl chloride did not occur under severe test conditions in the presence of known polymerlzation catalysts FeCl^. AlCl^ and air. A savings of 5*4 cents per 16 ounce unit can be realized by aerosol paint fillers if this propellant system is used rather than dichlorodifluoromethane (Freon 12, Genetron 12, Isotron 12). Based on 1957 production figures, 11.9 million pounds of dichloro difluoromethane were consumed in aerosol paints and thus a 5 to 10 million pound potential exists for vinyl chloride based on 50 to 100# replacement. IK, (9 220 00 - Halocarbons, Miscellaneous New ApplicatioTMns.)\.! 8.W.E. SEP 24'59 RESEARCH CLASSIFICATION; MATERIAL DISTRIBUTION; (* COMPLETE REPORT) * MIDLAND CRI (30*1..) * EXECUTIVE RESEARCH *J. C. Van Horn A. J. Pastor *E. W. Larabee, ARB *W. U. Seiler, ARB *R. L. Brown, 433 *R. K. Treichler, Fpt., A-2421 E. B. Barnes, Fot., B-1210 A. E. Schober *W. C. Bauman, 687 Problem No. 9 220 00 TS&D Files TYPE STAGE DISTRIBUTION IN MIDLAND CRf MAY 2 5 1993 *J. D. Kerr *D. K. Baliman, 47 T. J. Christiansen, ARB *N. R. Peterson, 4-33 W. A. Henson. 433 R. H, Smith, Fpt., B-121 *M. E. Pruitt, Fpt., B-1215 *M. J. Stoesser, Sarnia R. A. Lindsay 0.C. Cessna FOR USE OF DOW EMPLOYEES ONLY 2- - INTRODUCTION: An investigation was conducted to determine which Dow products could be used as low cost propellants for aerosol paints. The aerosol industry currently utilizes dichlorodifluoromethane, (Freon 12, Genetron 12, Isotron 12) hereafter called Propellant 12, as the propellant. Any replacement for Propellant 12 should be a low cost, liquifiable gas, low in toxicity, compatible with paint systems and have a boiling point such that substantial pressure will be exerted by the gas at room temperature. Knowing these requirements it was decided that vinyl chloride should perform satisfactorily as a propellant. The limitations of vinyl chloride as a propellant were determined. The limitations considered were; vapor pressure, possible polymeri zation of vinyl chloride containing formulations, flammability of finished formulations and market potential. The flammability of vinyl chloride would be its primary drawback. However, this should not be a detering factor as present aerosol paints are very flammable. EXPERIMENTAL WORK: Vapor Pressure Propellant 12, the pressurizing agent presently employed, exerts a pressure of 70 psig at 7CfF. A typical aerosol paint consists of 60# paint concentrate and 40# Propellant 12. This combination exerts a pressure of about 38 psig at 7CfF. Vinyl chloride boils at -13.27c. and at 7CPF. exerts 50 psig. Because paint concentrates are formulated to give a satisfactory spray pattern with Propellant 12 it was, therefore, necessary to increase the pressure of vinyl chloride to give a spray pattern similar to commercial systems. Propane was chosen as it is^an inexpensive liquifiable gas exerting a pressure greater than 70 psig at 7CfF. For 70 psig at 70F-, 76-9 vinyl chloride and 23-1# propane were required. This combination when packaged with 60$ paint concentrate produced a satisfactory spray. The 60# concentrate and 4o$ R&SI 68023 3- - propellant mix exerted a pressure of 42 psig at 7(fF. 42 psig is in excess of allowable package pressure. Commercial systems are packaged in containers in which the pressure may not exceed 40 psig at 7<fF. Forty percent of a propellant system (20# propane, 8o# vinyl chloride) and 60# paint concentrate exerted an acceptable pressure of 37 psig at 7<fF. and produced a satisfactory spray pattern. This 80:20 mixture was used for further evaluation. POLYMERIZATION OF VINYL CHLORIDE Because vinyl chloride monomer will undergo polymerization under certain conditions, it was necessary to determine if this could occur in aerosol paint systems. Dow vinyl chloride contains 1000 ppm phenol as a polymerization Inhibitor. A literature search revealed that t-butyl catechol is also an effective polymerization inhibitor, while air and certain metals and their salts catalyze polymerization. Tertiary butyl catechol was considered as an alternate inhibitor In the event aerosol packagers considered phenol too toxic. Aerosols were prepared with two lacquer solvent systems using the vinyl chloride/propane mix as the propellant. System No. 1 is suggested in the CSMA Aerosol Guide while System No. 2 was sug gested in the literature. They are: No. 1 No. 2 Methylisobutylketone Butyl acetate Isopropanol Butyl Cellosolve (Dowanol EB) Toluene 75% - 10# 10# 5# - 75# 10# 10# 5# Aerosol samples were prepared containing variables which could occur in aerosol containers. Our object being to determine if these variables catalyzed polymerization of the phenol containing vinyl chloride and if so, would TBC inhibit the polymerization? R&S168024 4- - Alr, ferric chloride, aluminum chloride and H^O were chosen as variables being possible in present aerosol systems. Air can.be introduced during the filling operation, particularly If, the pressure fill technique is employed. Ferric and aluminum chlorides' can re sult if there is any hydrolysis of vinyl chloride and subsequent attack of the steel or aluminum container. Water can be present either as a contaminant during the filling operation or coupled with solvents. Samples were prepared with the following variables: 1. 100# vinyl chloride/propane + air 2. 100# vinyl chloride/propane + air + 500 ppm TBC* 3. 100# vinyl chloride/propane, no air 4. 100# vinyl chloride/propane, no air + 500 ppm TBC 5. 40# vinyl chloride/propane + 60# No. 1 6. 40# vinyl chloride/propane + 60# No. 1 + 500 ppm TBC 7- 40# vinyl chloride/propane + 60# No. 2 8. 4o# vinyl chloride/propane + 60# No. 2 + 500 ppm TBC . #9. 4o# vinyl chloride/propane + 60# No. 1 + 0 1 anhydrous FeCl^ . #10. 40# vinyl chloride/propane 4- 60# No. 1 + 0 1 anhydrous FeCl^ + 500 ppm TBC . #11. 40# vinyl chloride/propane + 60# No. 1 + 0 1 anhydrous AlCl^ 12. 4o# vinyl chloride/propane + 60# No. 1 + 0.1# anhydrous AlCl^ + 500 ppm TBC 13* 40# vinyl chloride/propane + 60# No. 1 +' 0.1#*.distilled water 14. 40# vinyl chloride/propane + 60# No. 1 + 0.1#;.distilled water + 500 ppm TBC After two months storage at 12Cf F., the containers were examined. Samples 1-8 were in excellent condition. No corrosion or polymeri zation was evident. Samples 9-12 had crystal formations in the liquid phase. The crystals were collected and analyzed. Analysis showed these crystals to be inorganic with no organic material present. Tertiary butyl catechol R&S168025 5- - FLAMMABILITY: Present aerosol paint formulations containing 60# concentrate and 40# Propellant 12 are very flammable. The completed formulation when sprayed is capable of substaining a flame when the sSurce of ignition is removed. Aerosol paint containing 60# of solvent sys tem No. 1, 32# vinyl chloride and 8# propane were prepared and subjected to the same flame test. No appreciable difference was noted between this formulation and the above mentioned commercial formulation as far as flammability was concerned. The flame of the vinyl chloride-propane containing system was blue while the other system was a typical yellow. MARKET POTENTIAL: Vinyl chloride was considered primarily a propellant for aerosol paints. However, it should be applicable in any aerosol formulation where flammability is not a drawback. This would include presently flammable formulations and formulations used only outdoors such as weed killers and outdoor insecticides. In 1957 > 36.5 million cans of aerosol paints were produced*. To fill these cans 29.7 million pounds of complete formulations was required. Most formulations consisted of 60# concentrate and 40# Propellant 12. Based on this ratio, 11.9 million pounds of-Propel lant 12 were consumed. At present it is difficult to determine the sales volume of aerosol weed killers and outdoor Insecticides. Propellant 12 is 26.3 cents per pound In tank cars. The use of the vinyl chloride/propane propellant system would result In a savings of 5*4 cents per 16 ounce container, assuming the propellant to constitute 40# of the weight. This savings would be the primary reason for any manufacturer using vinyl chloride/propane rather than Propellant 12. At present vinyl chloride is being used as a propellant in Japan and Germany. The reason expressed for its lack of usage In the United States at present is Its flammability and the subsequent *AA Report 907 R&SI 68026 6- - dangers encountered in filling. However, current aerosol paints are flammable and many manufacturers have installed explosion proof equipment to avoid such accidents as happened to Thomasson of Pennsylvania (Krylon) several years ago when the paint concentrate caught fire destroying the entire operation. Therefore, the use of vinyl chloride/propane should not entail expensive modification of existing filling equipment. CONCLUSIONS: 1. Eighty percent vinyl chloride and 2056 propane can be used as a replacement for Propellant 12 in aerosol paints resulting in a savings of 5*4 cents per 16 ounce can. 2. Under most conditions encountered in aerosols, polymerization of vinyl chloride would not occur. 3. Flammability of aerosol paints containing vinyl chlorides/ propane Is not noticeably greater than commercial systems. 4. In most aerosol plants filling equipment would not have to be altered to use vinyl chloride/propane. 5* If vinyl chloride/propane were used exclusively In 1957* 9-5 million pounds of vinyl chloride would have been required. The following companies are engaged in production of aerosol paints: Aerolite Products, Incorporated 106 Ashland Avenue West Orange, New Jersey Capital Packaging 1441 South Circle Avenue Forest Park, Illinois T. J. Dunham Paint Company 115 Woodward Avenue Yonkers, New York Inland Paint and Chemical Company 2l44 West 49th Street Chicago, Illinois Kerr Chemical Company 9 South Farview Avenue Park Ridge, Illinois R&St 68027 7- - Red Ram Chemical Company 755 Utica Avenue Brooklyn 3, New York Red Devil Chemicals, Incorporated 30 North West Street Mount Vernon, New York Red Lion Chemical Co. l46 North Charles Street Red Lion, Pennsylvania Ronor Corporation 1360 West Ninth Street Cleveland, Ohio SprayOn Products Company 2075 East 65th Street Cleveland, Ohio Stalfort Pressure-Pak 321 West Pratt Street Baltimore 1, Maryland Thomasson of Pennsylvania, (Krylon) Norristown, Pennsylvania Cleveland Aerosol Packaging 9801 Harvard Avenue Cleveland 5> Ohio caj