摘要: Very fast, reversible, polyethylene (PE) chain transfer or complex-catalysed "Aufbaureaktion" describes a "living" chain-growing process on main-group metal zinc atom; this is catalysed by an organo-transition-metal lanthanide complex. PE chains are transferred very fast between the two sites and growth takes place through ethylene insertion into transition-metal- lanthanide-carbon bond-coordinative chain-transfer polymerisation (CCTP). The "rest" at centre, which chain-termination processes like beta-H transfer/elimination of low significance. Such protocols can be used to synthesise narrowly distributed materials (M(w)/M(n)<1.1 up molecular weight about 4000 g mol(-1)) with differently functionalised end groups. Higher molecular-weight polymers obtained slightly increased M(w)/M(n), since diffusion control precipitation influences process. Recently, few lanthanide-based catalyst systems that catalyse such highly reversible have been described. They summarised compared within contribution.
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