Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10609312 | European Polymer Journal | 2005 | 8 Pages |
Abstract
In this paper, two types of three-arm star mesogen-jacketed crystal polymers (MJLCPs) with different core (that is hard core and soft core) were synthesized by 2,5-bis[(4-methoxyphenyl)oxycarbonyl]styrene (MPCS), which was initiated by two different trifunctional initiators 1,3,5-(2â²-bromo-2â²-methylpropionato)benzene (Ia) and 1,1,1-tris(2-bromoisobutyryloxymethyl)propane (Ib), respectively. Characterization of these polymers by 1H NMR and GPC clearly supported the formation of a three-arm star-shaped PMPCS. The resulting three-arm star PMPCS possessed narrow molecular weight distribution, and its molecular weight (Mn,NMR) agreed well with the theoretical value, which reveals the quantitative initiation efficiency. The liquid-crystalline behaviors of the two types of three-arm star polymer with different structure were also investigated by differential scanning calorimeter (DSC) and polarized optical microscope (POM). We found that the liquid-crystalline behavior was incorrelated with structure of core but correlated with the length of three-arm star polymer arm. Only each arm of the three-arm star-shaped polymers with a Mn,GPC beyond 0.90Â ÃÂ 104 g/mol could form a liquid crystalline phase,which was found to be stable up to the decomposition temperature of these tri-arm MJLCPs.
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Authors
Xing-Zhu Wang, Hai-Liang Zhang, Da-Chuan Shi, Jian-Fang Chen, Xia-Yu Wang, Qi-Feng Zhou,