Patent Number: 6,310,138

Title: Hydrogenated block copolymer and polypropylene resin composition containing the same

Abstract: A hydrogenated block copolymer comprising: two polymer blocks A mainly comprising vinylaromatic hydrocarbon compound monomer units; and one hydrogenated polymer block B mainly comprising butadiene monomer units, in which at least 90% of olefinically unsaturated double bonds contained in a polymer block mainly comprising butadiene monomer units before hydrogenation have been hydrogenated, wherein a bonding vinylaromatic hydrocarbon compound content in the hydrogenated block copolymer is higher than 13 wt % but lower than 25 wt %, a 1,2-bond content in the unhydrogenated polymer block mainly comprising butadiene monomer units is higher than 40 mol % but lower than 60 mol %, and the copolymer has a quantity of heat of crystal fusion (.DELTA.H) smaller than 0.05 J/g, an order-disorder transition temperature of 200.degree. C. or higher, and a melt flow rate (MFR) value, as determined in accordance with JIS K7210 under the conditions of a temperature of 230.degree. C. and a load of 2.16 kg, of from not smaller than 0.1 g/10 min to smaller than 30 g/10 min. By incorporating the copolymer into a polypropylene resin, a composition which is suitable for giving a molded article having an excellent balance among impact resistance, brittle temperature, rigidity, heat distortion resistance, and tensile elongation at break, can be obtained.

Inventors: Yonezawa; Jun (Yokohama, JP), Kato; Kiyoo (Kawasaki, JP)

Assignee: Asahi Kasei Kabushiki Kaisha

International Classification: C08F 297/04 (20060101); C08L 23/00 (20060101); C08F 297/00 (20060101); C08L 23/10 (20060101); C08L 53/00 (20060101); C08L 53/02 (20060101); C08L 053/02 ()

Expiration Date: 10/30/2018