Abstract
BACKGROUND: Poly(olefin sulfone)s have been shown to form helical regions and to display main-chain liquid-crystalline behaviour in the bulk when they possess long side-chains. It is believed that increasing the tacticity of the backbone could enhance their liquid-crystalline behaviour. This study aims to produce tactic poly(olefin sulfone)s by stereospecific ring-opening polymerisation. RESULTS: Tactic polythiranes were successfully obtained from a racemic mixture of thirane monomers using a series of chiral catalyst systems. The isotactic placement (P-i) was determined using C-13 NMR analysis of carbons in or near the backbone. The polysulfides were oxidised by peracetic acid to their corresponding polysulfones. Powder X-ray diffraction studies showed that the isotactic polysulfones formed more ordered structures than their atactic analogues, an effect attributed to a tightening of the helical pitch. CONCLUSIONS: Tactic poly(1-hexene sulfone)s have been prepared for the first time by stereoselective ringopening polymerisation. (C) 2007 Society of Chemical Industry.
Original language | English |
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Pages (from-to) | 240-246 |
Journal | Polymer International |
Volume | 57 |
Issue number | 2 |
DOIs | |
Publication status | Published (in print/issue) - Feb 2008 |