Claims
- 1. A process for foaming and curing a phosphazene copolymer having randomly distributed repeating units represented by the formulas ##STR3## wherein R.sub.1 is linear or branched C.sub.1 to C.sub.10 alkoxy, R.sub.2 is hydrogen, linear or branched C.sub.1 -C.sub.10 alkyl or halogen, and W represents a monovalent radical containing a group capable of a crosslinking chemical reaction at moderate temperatures, said group being attached to a P atom by a -O- linkage, which process comprises mixing said phosphazene copolymer with a chemical blowing agent and a sulfur-type curing agent and heating the resulting mixture to a temperature sufficient to decompose said blowing agent and cure the copolymer.
- 2. The process of claim 1 wherein said blowing agent is 1,1'-bisazoformamide.
- 3. A process for foaming and curing poly(aryloxyphosphazene) copolymers having the general formula:
- [NP(OC.sub.6 H.sub.4 -R.sub.1).sub.a (OC.sub.6 H.sub.4 -R.sub.2).sub.b (W).sub.c ].sub.n
- wherein R.sub.1 is C.sub.1 -C.sub.10 linear or branched alkoxy; R.sub.2 is hydrogen, C.sub.1 -C.sub.10 linear or branched alkyl or halogen; W represents a monovalent radical containing a group capable of a crosslinking chemical reaction at moderate temperatures, said group being attached to a P atom by a -O- linkage; n is from 20 to 2000, a or b but not c O, and a+b+c=2, the ratio of a:b is from about 1:6 to 6:1, and the ratio of c:(a+b) is 9:10 to 5:100, which process comprises mixing said phosphazene copolymer with a chemical blowing agent and a sulfur-type curing agent and heating the resulting mixture to a temperature sufficient to decompose said blowing agent and curing the copolymers.
- 4. A phosphazene copolymer foam produced by the process of claim 1.
CROSS-REFERENCE TO RELATED APPLICATION
This is a division of application Ser. No. 768,603, filed Feb. 14, 1977.
US Referenced Citations (4)
Divisions (1)
|
Number |
Date |
Country |
Parent |
768603 |
Feb 1977 |
|