An entropy-driven ring-opening metathesis polymerization approach towards main-chain liquid crystalline polymers

摘要: The known synthetic methods of preparing main-chain liquid crystalline polymers (MCLCPs) are rather limited to several polycondensation reactions. However, the nature step-growth endows corresponding MCLCPs with relatively low molecular weights and broad weight distributions. In this manuscript, an entropy-driven ring-opening metathesis polymerization (ED-ROMP) approach is for first time applied in producing a MCLCP by polymerizing macrocyclic olefin monomer containing one cyclohexanecarboxylic acid phenyl ester group as mesogenic core icos-10-enedicarbonyl flexible aliphatic chain. For comparison, Yamaguchi macrolactonization ring-closing (RCM) used synthesize monomer, it turns out that although method can prepare pure RCM strategy advantageous providing much higher overall reaction yield. Furthermore, compared traditional acyclic diene (ADMET) α,ω-diene, ED-ROMP starting same monomer-to-catalyst ratio, releases no heat or volatiles during reaction, efficiently provide over shorter time.