BIOCOMPATIBLE SILICONE-ORGANIC THERMOPLASTICS-CONTAINING COMPOSITIONS

摘要

A flexible composition which is preferably radiopaque comprises a plastic material which may be mixed with from 10 to 50 percent by weight of a radiopaque filler. The plastic material comprises the product of (a) a block copolymer having thermoplastic, rubbery characteristics, having a central rubbery olefin block and terminal blocks of a polystyrene; (b) low crystallinity ethylene polymers such as poly (ethylene-vinyl acetate); and (c) a silicone gum containing a small amount of a silicon-bonded olefin group such as vinyl. Optionally, the addition of 5 to 40 percent by weight polypropylene may be included in these materials to improve their heat resistance and strength without affecting their transparency, when transparent materials are formulated.