| 摘要 |
PURPOSE:To prevent a block copolymer composed of a conjugated diene and an arom, vinyl hydrocarbon from being thermally deteriorated during heat treatment at a high temp. over a long period of time, by heat-treating said block copolymer in the presence of a specified stabilizer. CONSTITUTION:In the heat treatment of a block copolymer (A) composed of a conjugated diene and an arom. vinyl hydrocarbon under conditions satisfying 190<=T+15log t<=340 (wherein T is a treating temp. deg.C and t is a treating time in min, 0.01-10pts.wt. (per 100pts.wt. block copolymer) stabilizer contg. nitrogen and sulfur atoms in the molecule or said stabilizer and radical polymn. inhibitor in combination is/are blended. Examples of the stabilizers are phenothiazine and its derivatives. When the stabilizer and the radical polymn. inhibitor are used in combination, high-temperature heat treatment performance is synergistically improved so that a compsn. having more excellent characteristics can be obtd. |
