Synthesis and characterization of terminally carboxyl ethylene glycol monomethyl ethers‐substituted side‐chain liquid‐crystalline polysiloxanes

Alkene monomers containing phenyl or biphenyl carboxylate benzoate ester based on a mesogenic group of varied lengths of carboxyl oligo (ethanediol) monomethyl ethers as the terminal were synthesized. They were grafted onto poly(methyl‐hydrosiloxane) by the platinum‐catalyzed hydrosilylation process. The thermal transition temperatures and mesophase textures of monomers and of polymers were characterized by using differential scanning calorimetry (DSC), x‐ray diffraction, and polarized optical microscopy with a hot stage. The factors governing mesophase textures and thermal transition temperatures are discussed.