Journal article
Preparation of polystyrene-poly(ethylene glycol) diblock copolymer by "living" free radical polymerization
Amphiphilic diblock copolymer containing segments of polystyrene and monomethoxypoly(ethylene glycol) (PS-b-PEG) was synthesised by a novel method. Initially, the adduct (BZ-TEMPO) obtained by reacting benzoyl peroxide, styrene, and 2,2,6,6-tetramethyl-piperidinyl-1-oxy (TEMPO) was isolated, characterised and hydrolysed.
Conditions for the synthesis and hydrolysis of BZ-TEMPO were investigated and the hydrolysed product (HO-TEMPO) containing a primary hydroxyl group has been isolated in improved yield. The hydroxyl group of HO-TEMPO was coupled with tosylated PEG to yield the macroinitiator PEG terminated with a TEMPO unit (MPEG-TEMPO), which was further used to prepare the diblock copolymer PS-b-PEG by 'living' free radical polymerisation of styrene.
The product was purified and identified by H-1 n.m.r. and GPC. However, large amounts of homopolystyrene was also formed by simultaneous thermal initiation and polymerisation. (C) 1997 Elsevier Science Ltd.
Language: | English |
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Year: | 1998 |
Pages: | 911-915 |
ISSN: | 18732291 and 00323861 |
Types: | Journal article |
DOI: | 10.1016/S0032-3861(97)00341-8 |