The ternary composite was prepared from a miscible mixture of nematic liquid crystalline polymer (LCP) with a weak polar terminal unit in the mesogenic side group, nematic low molecular weight liquid crystal (LC) with a strong polar cyano end group (LC1) and LC with the similar chemical structure to the mesogenic side group of LCP (LC2). The reversible and bistable turbid-transparent states were successfully realized for the binary (LCP/LC1) and ternary (LCP/LC2/LC1) composites in an induced smectic phase upon the application of a.c. electric fields with low and high frequencies, respectively. The response speed for reversible light switching could be remarkably improved by an addition of LC2 to the binary composite at room temperature. The rise response time and decay one were a few seconds and several hundred ms, respectively. The molecular weight dependence of the electro-optical effect for the (LCP/LC) composite system was investigated by using LCPs with 12 or 40 of n. The magnitude of τD exhibited minimum for LCP with n=12, indicating that an appropriate length of polymeric main chain is required to realize an optimum condition for the balance between an electric field effect and an electric current effect.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)