Effect of polymer matrix density on molecular segregation and orientational ordering by a hybrid computer simulation

A hybrid computer simulation is used to study the effect of heterogeneous matrix density (pb) on the segregation and orientation of short-chain molecules, i.e., dimer, trimer, etc., a model for polymer dispersed liquid crystal (PDLC) in an external field. Size of molecular aggregates is found to increase with the matrix density, a polymerization-induced segregation consistent with the recent experimental observation (Boots and coworkers, Macromolecules 29 (1996) 7690; Liq. Cryst. 22 (1997) 145,255.). For low molecular weight liquid, the orientational ordering decreases monotonically with pb, while the orientation in a higher weight liquid depends nonmonotonically on pb.