The improvement of electro-optical properties of polymer-dispersed liquid crystals with graft copolymer matrix synthesized by reversible addition-fragmentation chain transfer and atom transfer radical polymerization

Abstract

Aiming to decrease the memory effect of polymer-dispersed liquid crystals (PDLCs), a type of graft macroinitiator, synthesized by reversible addition–fragmentation chain transfer and atom transfer radical polymerization, was employed to prepare PDLCs with graft copolymer matrix in our previous work. Compared with linear copolymer matrix PDLCs prepared using a linear macroinitiator, it was found that, although low-memory-effect PDLCs were obtained, the driving voltage and transmittance of the PDLCs were unfortunately sacrificed to some extent. Thus, it is necessary to improve the electro-optical properties of PDLCs on the basis of the original research performed by us. In the work reported in this article, a kind of linear macroinitiator with high refractive index and another graft macroinitiator with flexible branched chains were employed to prepare PDLCs. The results showed that by using mixed macroinitiators, the electro-optical properties of PDLCs could be improved, and a possible mechanism is proposed.