Author(s): HE Xiao-zhi, YU Fei-fei, SONG Zi-yan, HU Jian-she, School of Sciences, Northeastern University
Pages: 1150-1154
Year: 2015 Issue:  8
Journal: Journal of Northeastern University(Natural Science)
Keyword:  chiral; choleateric; fluorine-contained; elastomer; Grandjean blue;
Abstract: Nematic monomer: 4-( 4-( allyloxy) benzoyloxy) phenyl 4-fluorobenzoate( M1) and non-liquid crystalline crosslinking agent: bis(( 4-( 4-allyloxy) benzoyloxy) isosorbide benzoate)( MC) were synthesized. M1 and MCwith different proportions reacted with polymethylhydrosiloxane and chiral liquid crystalline elastomers containing fluorine PI-PVIII were got. The chemical structures and mesomorphic properties of monomers and elastomers were studied by means of FT-IR,1H NMR,POM,DSC,TGA and X-ray. The experiment results showed that short-hard liquid crystal elements containing fluorine could be induced into cholesteric phase with wonderful properties. PI presented nematic phase and PII-PVII displayed cholesteric phase with oily-streak and Grandjean texture. PVIII did not have any liquid crystalline properties.The glass-transition temperature increased first and then decreased,whereas both the melting point and clearing point decreased. The synthesized liquid crystal elastomers had good thermal stability,and the thermal weight loss temperature was greater than 300 ℃ with only 5% weight lost.