PREPARATION OF A NEW-TYPE OF PHOSPHAZENE HIGH POLYMERS CONTAINING 2,2'-DIOXYBIPHENYL GROUPS

The direct reaction of [NPCl2](n), with the difunctional reagent 2,2'- dihydroxybiphenyl (HOC6H4C6H4OH) and K2CO3 in tetrahydrofuran gave sol uble linear phosphazene high polymers instead of the expected cross-li nked products. The reaction of [N3P3Cl6] with 1, 2, or 3 equiv of HOC6 H4C6H4OH and K2CO3 in acetone gave the known spiro derivatives [N3P3Cl 4(O2C12H8)], [N3P3Cl2(O2C12H8)(2)], and [N3P3 (O2C12H8)(3)] without fo rmation of bridging products, and the dichloro derivative reacted dire ctly with parasubstituted phenols HOC(6)H(4)R and K2CO3 in acetone to give the new compounds [N3P3(OC(6)H(4)R)(2)(O2C12H8)(2)] (R = Br, COC6 H5, or OCH3), without signs of replacement of the bis(aryloxy) substit uents. In an analogous manner, poly(dichlorophosphazene) [NPCl2](n) re acted with HOC6H4C6H4OH and K2CO3 in THF without significant cross-lin king to give, depending on the mole ratio, the soluble polymer [NP(O2C 12H8)](n) (M(w) = 450 000, T-g = 160 degrees C) or the partially subst ituted polymers {[NP(O2C12H8)](0.35)[NPCl2](0.65)}(n) The latter were subsequently reacted with the para-substituted phenols HOC(6)H(4)R and K2CO3 in THF to give the random copolymers {[NP(O2C12H8)](0.35)[NP(OC (6)H(4)R)(2)](0.65)}(n) [R = Br, CN, COCH3, or COC6H5). The new polyme rs are soluble (except the CN derivative, which was sparingly soluble) white solids, with only a few ppm of unreacted chlorine, and M(w) of the order of 1 000 000 with polydispersities varying from 3 to 10. The T-g values varied with R ranging from 73 degrees C (R = CN) to 54 deg rees C (R = COMe).