Catalytic production of olefin block copolymers via chain shuttling polymerization
Catalytic production of olefin block copolymers via chain shuttling polymerization
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DOI：
10.1126/science.1125268
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发表时间：
2006-05-05
期刊：
影响因子：
56.9
通讯作者：
Wenzel, TT
中科院分区：
文献类型：
--
作者：
Arriola, DJ;Carnahan, EM;Wenzel, TT
我们报告了一种催化系统，可生产具有交替半结晶和无定形链段的烯烃嵌段共聚物，通过改变两种类型嵌段中α-烯烃与乙烯的比例来实现。该系统使用链穿梭剂在单个聚合反应器中具有不同单体选择性的两种不同催化剂之间转移生长的链。嵌段共聚物同时具有高熔融温度和低玻璃化转变温度，因此它们在高温下保持优异的弹性体性能。此外，这些材料可以在经济上有利的连续聚合工艺中有效地生产。
We report a catalytic system that produces olefin block copolymers with alternating semicrystalline and amorphous segments, achieved by varying the ratio of alpha-olefin to ethylene in the two types of blocks. The system uses a chain shuttling agent to transfer growing chains between two distinct catalysts with different monomer selectivities in a single polymerization reactor. The block copolymers simultaneously have high melting temperatures and low glass transition temperatures, and therefore they maintain excellent elastomeric properties at high temperatures. Furthermore, the materials are effectively produced in economically favorable, continuous polymerization processes.