Block copolymer composition, a process for its preparation and a hot melt adhesive comprising said composition
申请人:SHELL INTERNATIONALE RESEARCH
MAATSCHAPPIJ B.V.
公开号:EP0636654A1
公开(公告)日:1995-02-01
Block copolymer composition, comprising:
(a) 100 parts weight of a linear styrene/isoprene/styrene triblock copolymer, said copolymer having a styrene content in the range of from 10 to 50% by weight based on the total weight of block copolymer, and apparent total molecular weight in the range of from 5,000 to 300,000, said block copolymer composition having free poly(styrene) content of at most 6% and being obtainable by anionic sequential polymerization of styrene and isoprene in a solvent comprising of cyclopentane and/or cyclohexane, optionally in combination with second initiation to provide triblock copolymer being mixed with a predetermined amount of <+ 40 wt% of diblock copolymer; termination of the living block copolymer(s) with a proton donating terminating agent; and recovery of the final block copolymer(s) from the solvent solution by hot water and/or steam coagulation dewatering and/or drying and/or mixing in a predetermined well adjusted amount of similar block containing diblock copolymer, the final block copolymer composition having a solution viscosity in toluene (25 wt%) at 25 °C in the range of from 0.1 to 3
(b) 0.1 to 5 parts by weight of a stabilizer set comprising:
I one or more specific UV stabilizer, and one or more phosphite antioxidants, and adhesive hot melt compositions containing said composition.
嵌段共聚物组合物,包括
(a) 100 重量份的线性苯乙烯/异戊二烯/苯乙烯三嵌段共聚物,以嵌段共聚物总重量计 算,苯乙烯含量在 10%至 50%(重量百分比)之间,表观总分子量在 5,000 至 300,000 之间、所述嵌段共聚物组合物的游离聚苯乙烯含量不超过 6%,可通过苯乙烯和异戊二烯在环戊烷和/或环己烷组成的溶剂中进行阴离子序聚合反应获得,也可选择与第二引发结合,以提供与预定量 <+ 40 wt% 的二嵌段共聚物混合的三嵌段共聚物;用质子捐赠型终止剂终止活嵌段共聚物;通过热水和/或蒸汽凝固脱水和/或干燥和/或与预定量的含有二嵌段共聚物的类似嵌段充分混合,从溶剂溶液中回收最终嵌段共聚物,最终嵌段共聚物组合物在 25 °C 时在甲苯(25 wt%)中的溶液粘度范围为 0.1 至 3
(b) 0.1 至 5 重量份的稳定剂组,包括
I 一种或多种特定紫外线稳定剂和一种或多种亚磷酸酯抗氧化剂,以及含有所述组合物的粘合剂热熔胶组合物。