New side chain liquid crystal polymers having 1,3-dithiane or 1,3-oxathiane rings as mesogenic side groups

New liquid crystal polymers having a 1,3-dithiane ring or 1,3-oxathiane rin g were synthesized. First, the syntheses of new polymerizable liquid crysta l monomers with a 1,3-dithiane ring or 1,3-oxathiane ring in their principa l structures are discussed. Then the polymerization of these monomers and s yntheses of side chain type polysiloxanes are discussed. The mesomorphic be haviors of these liquid crystal monomers and polymers are also discussed. T hese new liquid crystal polymers exhibit liquid crystal phase at around roo m temperature, and have lower nematic-sotropic transition temperatures than those of the corresponding 1,3-dioxane type liquid crystal polymers.