Si-CONTAINING, FERROELECTRIC LIQUID CRYSTAL COPOLYMERS, A PROCESS FOR PRODUCING THE SAME, MIXTURES OF THESE COPOLYMERS WITH LOW MOLECULAR WEIGHT LIQUID CRYSTALS AND THEIR USE IN ELECTRO-OPTIC COMPONENTS

摘要

A liquid crystal copolymer has the formula (I), in which l, m, p, q, r, s are equal to zero or to an integer between 1 to 100, independently from each other, provided that the sum l+m+p+q+r+s is an integer greater than 2 and that at least two of the indices m, p, q, r, s are greater than zero; n = 1 to 500; Y?1, Y2, Y3, Y4, Y5？ are a group of general formula (CH？2?)a(-B)b-M?1(-A1)？c(-M2)d(-A2)e(-M3)f(-A3)g-R1, independently from each other, whereas B is for example a group having the formula α, in which R?6, R7, R8？ are for example H or CH？3? and X is for example chlorine; R?1？ is for example a straight chain alkyl with 1 to 16 C atoms; a = 2 to 20; b, c, d, e, f, g = 0 or 1; A?1, A2, A3？ are for example phenylene or pyrimidine-2,5-diyl; M?1, M2, M3？ are for example COO or OCO. This copolymer is particularly useful as component of liquid crystal switching devices.