EFFECT OF CURING PROGRESS ON THE ELECTROOPTICAL AND SWITCHING PROPERTIES OF PDLC SYSTEM

Experimental studies on the morphology and thermal and electrooptical behavior of PDLC films consisting droplets of nematic LC (6CB) up to a 40% weight fraction in a polyester resin matrix crosslinked by diacry lane are presented. The PDLC samples were prepared by LC separation fr om a solution in a UV-polymerizing oligoester resin between TIG-coated glass plates. The electrooptical and switching results depending on t he UV curing time of the polyester matrix are shown. The curing proces s of the polymer binder leading to phase separation of the LC causes i ncreasing polymer stiffness affected by the boundary condition on the LC droplets. The reorientational dynamics of LC in PDLC, which reflect s the character of switching curves for varying voltage and with progr essing curing (varying from 40 s to 15 min), is discussed on the basis of the kinetic analysis of light scattering by the system. (C) 1999 J ohn Wiley & Sons, Inc.