Structural Characteristics and Thermal Properties of Poly(methyl methacrylate) and Atactic Polystyrene Grafted onto Metallocene Based Ethylene-allylbenzene Copolymer

摘要

This investigation attempts to elucidate the copolymerization reaction ethylene and allylbenzene via the homogeneous metallocene catalyst, Et(lnd)_2ZrCI_2 and (nBuCp)_2ZrCl_2. The pendant benzyl groups of ethylene-allylbenzene copolymer (EAB) are potentially ready for numerous chemical reactions, such as halogenation and acylation, which can introduce functional groups at the side benzyl groups under mild reaction condition. In this study, polyethylene-g-poly(methyl methacrylate) and polyethylene-g-atactic polystyrene were synthesized by a heterogeneous atom transfer radical polymerization (ATRP) using α-phenyl-chloroacetyl chloride modified poly(ethylene-co-allylbenzene) (PCAEAB) as macroinitiator and copper chloride combined with 2,2'-bipyridine as catalyst in a heterogeneous process. The macroinitiator with 0.78 mol% chlorine content was prepared from Friedel-Crafts acylation reaction of ethylene-allylbenzene copolymer (1.0 mol% allylbenzene content) with α-phenyl-chloroacetyl chloride in a heterogeneous process. The structure of resultant polymers was determined by ~1H NMR and FTIR spectroscopies. In addition, the thermal properties of polymers were also investigated with differential scanning calorimetry (DSC). Morphology of resultant polymers was investigated by SEM.