Dynamic mechanical behavior of a side-chain liquid crystalline polyacrylate

✍ Scribed by M. Laus; D. Ferri

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 521 KB
• Volume: 34
• Category: Article
• ISSN: 0887-6266
• DOI: 10.1002/(sici)1099-0488(19960430)34:6<1085::aid-polb6>3.0.co;2-x

✦ Synopsis

The phenomenology of the a-and p-relaxation processes in an amorphous and a crystallized specimen of a side-chain LC polyacrylate, based on the azobenzene mesogenic unit, was investigated by thermal and dynamic mechanical methods. The activation energy of the p relaxation of the crystallized sample is equal to that of the amorphous sample. The atransition process of the amorphous sample was described by the WLF equation. In contrast, the a-relaxation behavior of the amorphous part of the semicrystalline sample was described by a double Arrhenius law broken at T = Tr This peculiar behavior has been tentatively related to the decrease of the motion characteristic length of the macromolecules confined in the multidomain structure of the semicrystalline state.