INDUCTION OF SMECTIC LAYERING IN NEMATIC LIQUID-CRYSTALS USING IMMISCIBLE COMPONENTS - 2 - LATERALLY ATTACHED SIDE-CHAIN LIQUID-CRYSTALLINEPOLY(NORBORNENE)S AND THEIR LOW-MOLAR-MASS ANALOGS WITH HYDROCARBON OLIGODIMETHYLSILOXANE SUBSTITUENTS/

In contrast to their hydrocarbon analogues which exhibit only nematic mesophases, poly{5-[[[2',5'-bis[(4 ''-(n-(dimethylsiloxyl oxy]benzyl]o xy]carbonyl]bicyclo[2.2.1]hept-2-ene}s and their low-molar-mass model compounds exhibit smectic C mesophases. Since nematic liquid crystals can be forced into layers by terminating their hydrocarbon substituent s not only with fluorocarbon segments but also with flexible siloxane segments, this supports the hypothesis that the smectic mesomorphism o f amphiphilic molecules containing linear fluorocarbon segments is due primarily to the immiscibility of the hydrocarbon and fluorocarbon se gments, rather than to a shape persistence of ''mesogenic perfluoroalk yl rods''. The -(oligodimethylsiloxyl)alkoxy)benzoyl)oxy]toluenes mimi c both the phases formed by the polymers and the general temperatures of their transitions and are therefore excellent models of the polymer s. The 5-{[[2',5'-bis[(4 nzoyl)oxy]benzyl]oxy]carbonyl}bicyclo[2.2.1]h ept-2 enes were polymerized by ring-opening metathesis polymerization in THF at room temperature using Mo(CHCMe2Ph)(N-2,6-(Pr2Ph)-Pr-i)((OBu )-Bu-t)(2) as the initiator.