Polymers from siloxane‐containing epoxides

The synthesis and polymerization of seven epoxy polymer precursors which contained the siloxane linkage in varying structural arrangements was carried out. The polymers prepared from such precursors have utility as embedding compounds for electrical circuits. Polymerization of these epoxy intermediates with siloxane‐containing diamines resulted in solid, thermosetting materials for which dielectric data were obtained. Dielectric constants of 3.1 were measured at 1 keps for polymers prepared by polymerization of 1,9‐bis[p‐(2,3‐epoxypropyl)phenyl]decamethylpentasiloxane with 1,3‐bis(p‐am‐inophenoxy)tetramethyldisiloxane, whereas polymers derived from 1,4‐bis{[p‐(2,3‐epoxypropyl)phenyldimethylsiloxy]dimethylsilyl}benzene and the same diamine were characterized by slightly higher dielectric constants and a high degree of toughness, being nonbrittle at −50°C.