| 摘要 |
<p>Polymer dispersed liquid crystal (PDLC) films are prepared by ultraviolet curing of monomer/liquid crystal solutions with a copolymerizable photoinitiator instead of a traditional photoinitiator. As a consequence of this method of preparation, there is less initiator contamination of the separated liquid crystal phase in the PDLC films, since most of the copolymerizable initiator is trapped in the polymer matrix rather than in the LC phase, whether the LC is present as droplets or as part of a network or gel morphology. Because the LC phase in the PDLC is less contaminated by initiator, the following advantages are realized: (1) the LC phase has a wider temperature range and a higher clearpoint than PDLC films prepared with conventional photoinitiators; (2) the PDLC has a higher resistivity and better electro-optical characteristics than films prepared with conventional photoinitiators; and (3) the PDLC has increased device photostability as a consequence of initiator being trapped in the polymer matrix causing less PDLC degradation than initiator dissolved in the LC phase. This invention is applicable for the attainment of both droplet or network morphology PDLC films, including network gels. <IMAGE></p> |
