Ethylene-propylene rubber constituent null for vulcanized rubber

摘要

PURPOSE: To obtain an ethylene-propylene rubber compsn. excellent in the balance between processibility and mechanical characteristics of the product and in kneadability by compounding an ethylene-prolylene rubber with a specific polyethylene in a specified wt. ratio. ;CONSTITUTION: This rubber compsn. comprises 100 pts.wt. ethylene-propylene rubber and 5-40 pts.wt. polyethylene. The polyethylene is a copolymer of ethylene with 10-30wt.% 4-8C α-olefin and has a specific gravity of 0.900-O.915, a m. p. measured by DSC of 90-115°C, and a degree of crystallization measured by the X-ray method of 20-50%. The rubber pref. has a Mooney viscosity [ML₁₊₄(100°C)] of 50-250, an ethylene content of 65-80mol%, and an iodine value of 5-40. The compsn. is pref. vulcanized before it is used and pref. contains 20-400 pts.wt. reinforcement and 20-100 pts.wt. softener based on 100 pts.wt. rubber.;COPYRIGHT: (C)1995,JPO