Abstract
Dielectric relaxation spectra have been measured for a series of siloxane based side-chain liquid crystal polymers and the effect of the spacer group chemical structure (alkyl and vinylacetic acid) on dielectric motion is presented, as is the effect of spacer length for each polymer with a given spacer type. The effect of increased spacer length is to increase the frequency of motion due to greater mesogen mobility. The materials containing vinylacetic acid spacer units show a biomodal dielectric frequency spectrum due to greater decoupling of the constituent motions of the side chains. The effect of spacer length on the cross-over frequency (which determines the nature of the liquid crystalline alignment by a.c. electric fields of various frequencies) is also discussed.
Original language | English |
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Pages (from-to) | 1201-1207 |
Number of pages | 7 |
Journal | European Polymer Journal |
Volume | 30 |
Issue number | 11 |
DOIs | |
Publication status | Published - 1 Jan 1994 |