| 摘要 |
<p>1,142,089. Vinyl chloride copolymers. AIR REDUCTION CO. Inc. 18 Dec., 1967 [30 Dec., 1966], No. 57292/67. Heading C3P. A vinyl chloride-ethylene-propylene terpolymer preferably has a combined ethylene-propylene content of up to 10% by weight and an ethylene to propylene ratio of 5: 1 to 1: 20. It may be prepared by solution, mass or emulsion technique, but preferably in aqueous suspension using a suspending agent, e.g. polyvinyl alcohol or methyl cellulose, and a surface-active agent, e.g. sodium dioctyl sulphosuccinate. The catalyst is preferably a monomer-soluble peroxy or azo catalyst and a water-soluble promoter may also be present, e.g. sodium bisulphite. A pH of 5-8À5 is maintained with a buffering agent. The vinyl chloride may be added stepwise. The products may be moulded. Conventional stabilizers, lubricants, fibrous and non-fibrous fillers, pigments, other polymers and plasticizers if required are listed.</p> |
