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Synthesis and characterisation of telechelic poly(2,6-dimethyl-1,4-phenylene ether) for copolymerisation
[摘要] Telechelic poly(2,6-dimethyl-1,4-phenylene ether) (PPE) segments are interesting starting materials, for example for copolymerisation. A good method to make partly bifunctional PPE-2OH is by redistribution or depolymerisation of high molecular weight commercial PPE with tetramethyl bisphenol A. The product has a bimodal molecular weight distribution because only similar to70-80% of high molecular weight starting material is depolymerised. The phenolic endgroups can be modified easily by a fast and complete reaction with methyl chlorocarbonyl benzoate. The product after endgroup modification is called PPE-2T and has two terephthalic methyl ester endgroups and a molecular weight of 2000-4000 g/mol. The functionality of these PPE-2T products is around 1.8. The bimodal PPE-2OH and PPE-2T products can be separated in a high and low molecular weight fraction by selective precipitation. The low molecular weight fraction has a narrow molecular weight distribution with a polydispersity between 1.2 and 1.5. (C) 2003 Elsevier Ltd. All rights reserved.
[发布日期] 2003-11-01 [发布机构] 
[效力级别]  [学科分类] 
[关键词] poly(2,6-dimethyl-1,4-phenylene ether);redistribution;telechelic [时效性] 
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