covered by dissolving it in N-methylpyrrolidone. Ethylene and propylene are separated by conventional lowtemperature fractionation. In the latest version of the Tsutsumi process, also described at the World Petroleum Congress, light naphtha and oxygen are reacted under vacuum to make acetylene and ethylene. Operation at pressures of 200 mm. Hg and less lowers the reaction temperature to about 1000° C. Besides these processes, various companies offer many other processes to make acetylene from hydrocarbons. Other partial combustion processes include the Phillips Petroleum tangential reactor, the Eastman two-stage burner, and the Hydrocarbon Research process. The only electric arc discharge process developed in the U.S. to gain much attention is one developed by the late Dr. E. P. Schoch and co-workers at the University of Texas. Rights to the Schoch process now are held by Standard Oil Co. (N.J.). Future. The many acetylene processes indicate the extent of efforts to find ways of making acetylene at costs which permit products from it to compete with products from other raw materials such as ethylene. Acetylene can be made into many other products than now are made commercially, but most of these products are in little demand. If cost of acetylene should drop radically, then acetylene may
C&EN PROGRESS REPORT
capture some uses from its major competitor, ethylene. Whether the several processes now arriving on the commercial scene can really lower the cost of acetylene will be known in one to two years, one observer points out. If cost-saving develops in manufacture of acetylene, through extra values in by-products, or by efficient utilization of other plant by-products in reactions with acetylene, then a new round of plant expansions and possible replacement of less efficient existing plants may begin. Nor is process development over for acetylene, suggests one authority. For example, greater knowledge of plasma jet technology may bring new and lower cost methods.
Plasticizer for Plastisols Has Little Odor and Color A new plasticizer for plastisol production of rigid vinyls is now available from Monsanto Chemical. Like those now on the market, the compound (trade-named Santoset 1) is a homopolymerizing plasticizer. However, it has little odor and color and gives plastisols that store better than those formulated with competitive plasticizers, according to Monsanto. Plastisol methods have been largely limited to producing flexible products. Rigid products are usually extruded, vacuum formed, or blow molded.
Still, plastisol plasticizers for making rigid vinyls have been available for the last decade. Rohm & Haas has offered its thermosetting monomer X-970, the dimethacrylate ester of 1,3-butylene glycol. Borden Chemical markets M PL, a dimethacrylate ester of tetraethylene glycol. Sartomer Resins, Inc., a specialty monomer producer, supplies these and other esters for rigid vinyl plastisols. Prices of the various plasticizers are about $1.00 per lb. A big problem has been storage of the plastisol formulation prior to its use. In many cases, the plasticizers will solvate the polyvinyl chloride resin. Troublesome, too, are the catalysts, which on standing will polymerize the monomer. This can be minimized by storing at cool temperatures. Sartomer's answer to the storage problem is its SR350, a trimethacrylate ester of trimethylol propane. This plasticizer doesn't solvate the PVC resin as readily as the dimethacrylate ester derivatives, Sartomer says. The company is currently offering SR350 for $1.50 per lb. in drum lots. Volume production, though, would drop the price to the $1.00 per lb. level, Sartomer says. New Markets. Premixing of Santoset 1 with the catalyst, di-ieri-butyl peroxide, doesn't affect its storage life, Monsanto points out. The reactive plastisol (formulation of PVC
ifOSÏRIftt CHEMICAL SPECIALTIES
Companies added these products to their lines during the past month Material
Alizarin blue (Calcocid SEB) Fabric finish (Ampitol CPE-70)
Company American Cyanamid Co. Bound Brook, N J . Dexter Chemical Corp. New York, N.Y.
Electrolytic cleaning additive (EC-9)
Panther Chemical Co. Fort Worth, Tex.
Styrene-acrylic copolymer (NeoCryl CC-8)
Polyvinyl Chemicals, Inc. Peabody, Mass.
One-step sealant (Poly-Tite) Polyvinyl alcohols (Resins D-364 and D-369)
Sandell Mfg. Co. Cambridge, Mass. Shawinigan Resins Corp. Springfield, Mass.
Available in commercial quantities unless otherwise noted.
58
C&EN
JULY
2 2, 1963
Feature For dyeing wool, nylon, and Creslan acrylic fiber Contains high-melting, inert resins, improves sewing and cutting characteristics of fabrics Blend of detergents and synthetic surfactants, said to reduce reruns by more than 4 2 % For use in floor sealer formulations, can be used either as undercoat or as top finish Fills and seals joints in metal, concrete, or any curtain wall construction Partially hydrolyzed grades dissolve easily in cold water, are useful as emulsifying agents
