| 摘要 |
PROBLEM TO BE SOLVED: To provide a hydrogenated block copolymer for obtaining a polypropylene resin composition having excellent balance of flexibility, thin-wall moldability, stress whitening resistance, mechanical properties and transparency.SOLUTION: Such a hydrogenated block copolymer comprises a polymer block A composed mainly of a vinyl aromatic monomer unit and a polymer block B composed mainly of a conjugated diene monomer unit whose total of 1,2-bond content and 3,4-bond content before hydrogenation is 65 to 90%. The content of the polymer block A is 12 to 25 mass% and at least 90% or more of the olefinic unsaturated double bond of the polymer block B is hydrogenated, and has a melt flow rate value (MFR) of 15 to 60 g/10 min measured under the condition of temperature of 230°C and 2.16 kg of weight and an orderly-disorderly transition temperature (ODT) within a range of 160 to 210°C measured by dynamic viscoelasticity. |
