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Rigid-rod liquid crystalline polyesters based on n-alkoxyterephthalic acid and 4,4′-dihydroxybiphenyl

✍ Scribed by Pio Iannelli; Ugo Caruso; Stefania Pragliola; Antonio Roviello; Augusto Sirigu

Publisher
John Wiley and Sons
Year
1998
Tongue
English
Weight
148 KB
Volume
36
Category
Article
ISSN
0887-624X

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✦ Synopsis

The synthesis and the characterization of a set of polymers obtained by polycondensation of n-alkoxyterephthalic acid (n Å 1, 3, 5, 7) and 4,4-dihydroxybiphenyl are reported. The n-alkoxy insertion promotes the processability of the material by lowering the melting temperature. All polymers show the nematic phase at about 300ЊC, almost independently of the length of lateral substituent. The isotropization is not observed up to 450ЊC, where thermal decomposition occurs. The temperature of glass transition decreases with increasing n, ranging from 170ЊC (n Å 5) to 220ЊC (n Å 1).

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