PURPOSE: To obtain a modified polyolefin resin compsn. which has excellent high-temp. mechanical strengths and an improved normal-temp. softness by compounding a crystalline polyolefin with an acid-modified crystalline polyolefin and an amorphous polyolefin.
CONSTITUTION: A crystalline polyolefin is melt mixed with 20-80wt.% acid- modified crystalline polyolefin and 80-20wt.% amorphous polyolefin and kneaded. The former crystalline polyolefin is a homopolymer, a dual copolymer, or a multicomponent copolymer formed from a monomer or monomers selected from among ethylene, propylene, and 4-8C α-olefins and has a number average mol.wt. of 30,000 or higher. The acid-modified crystalline polyolefin is formed by grafting at least one unsatd. carboxylic acid component selected from among a 3-10C unsatd. carboxylic acid, its anhydride, and its ester and has an acid value of 1-200mgKOH/g. The amorphous polyolefin is a homopolymer, a dual copolymer, or a multicomponent copolymer formed from a monomer or monomers selected from among ethylene, propylene, and 4-8C α-olefins and has a number average mol.wt. of 2,000-40,000, a heat of crystal fusion of 20J/g or lower, and a boiling-n-heptane insol. content of 70wt.% or lower.
KUNIMURA MASARU
TSURUYA IWAO
UBE REKISEN KK