| 摘要 |
A process is described for preparing compositions comprising ethylene copolymers, such as ethylene-acrylate or ethylene-vinyl acetate copolymers, and compatible liquid hydrocarbons which act as inexpensive plasticizers or extenders, the process enabling large quantities of inert, e.g. inorganic fillers to be incorporated more simply than previously proposed processes. The hydrocarbon is compatible if it satisfies the test that there is no observable exudation of hydrocarbon from the copolymer when 50 g. of powdered copolymer are mixed with a quantity of hydrocarbon in a metal dish which is first heated to 120 DEG C. to fuse the copolymer, second cooled and held at a temperature of -20 DEG C. for 18 hours, and third warmed to room temperature. The compositions may be prepared either in the form of free-flowing powders or aqueous dispersions both of which are described and both of which have advantages when used in described situations as hot melt adhesives or coating compositions, especially for carpet backing techniques.
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