The multilayer device of claim 9 wherein said divalent radical A is a radical having the formula ##STR72## wherein each of U and X is a substituent other than hydrogen, and said divalent radical B is a radical having the formula ##STR73## wherein U is a substituent other than hydrogen, each W is hydrogen or a substituent other than hydrogen, p is an integer from 1 to 3, each X is hydrogen or a sub