A. H. Al-dujaili, A. T. Atto, Adel M Al-Kurde
May 1, 2001
Citations
0
Influential Citations
40
Citations
Journal
European Polymer Journal
Abstract
Abstract Model compounds and polymers were prepared by condensation of 2,5-bis(4-hydroxyphenyl)thiazolo[5,4-d]thiazole and 2,5-bis(4-hydroxy-3-methoxy)thiazolo[5,4-d]thiazole with chlorotrimethylsilane, dichlorodimethylsilane, dichlorodiphenylsilane and tetrachlorosilane respectively. The molecular weights of the synthesized polymers were calculated from intrinsic viscosity measurements using Mark–Houwink equation. The thermotropic liquid crystalline properties were examined by differential scanning calorimetry and microscopic observations. Model compounds do not exhibit mesomorphic properties while all the polymers except those derived from tetrachlorosilane, exhibit thermotropic liquid crystalline properties. They exhibit nematic thread-like or schlierene texture when examined by the polarizing microscopy. The mesophase type and formation is discussed in terms of chemical structure of the synthesized models and polymers.