Claims
- 1. Regenerated cellulose filaments and articles having dispersed therein a flame retardant amount of a phosphonitrilate polymer prepared according to the process comprising reacting, in the presence of an amount of an acid acceptor sufficient to complex with at least twice the molar amount of hydrogen halide formed, a phosphonitrilic halide with a hydroxyl compound selected from aliphatic alcohols having from one to about six carbon atoms and aromatic alcohols having from six to about ten carbon atoms according to the steps of
- (a) contacting a mixture of said phosphonitrilic halide and said acid acceptor with at least about 85 to about 180 weight percent of the theoretical amount based on said phosphonitrilic halide of said hydroxyl compound at a temperature of not more than about 40.degree. C, whereby a relatively low concentration of said hydroxyl compound is present during the initial 1/2 to about 3 hours of the reaction and whereby condensation occurs between intermediate phosphonitrilate alkoxy or aryloxy ester species and phosphonitrilic halides or partially esterified phosphonitrilates with the evolution of an alkyl or aryl halide compound, and
- (b) thereafter, maintaining the reaction mixture at a temperature of from about 20.degree. to about 50.degree. C for a period of from about 1/2 to about 120 hours.
- 2. A method of preparing a flame retardant regenerated cellulose filament which comprises mixing viscose and a flame retardant amount of a phosphonitrilate polymer, shaping the mixture into a filament, and coagulating and regenerating said filament, said phosphonitrilate polymer being prepared by a process comprising reacting, in the presence of an amount of an acid acceptor sufficient to complex with at least twice the molar amount of hydrogen halide formed, a phosphonitrilic halide with a hydroxyl compound selected from aliphatic alcohols having from one to about six carbon atoms and aromatic alcohols having from six to about ten carbon atoms according to the steps of
- (a) contacting a mixture of said phosphonitrilic halide and said acid acceptor with at least about 85 to about 180 weight percent of the theoretical amount based on said phosphonitrilic halide of said hydroxyl compound at a temperature of not more than about 40.degree. C, whereby a relatively low concentration of said hydroxyl compound is present during the initial 1/2 to about 3 hours of the reaction and whereby condensation occurs between intermediate phosphonitrilate alkoxy or aryloxy ester species and phosphonitrilic halides or partially esterified phosphonitrilates with the evolution of an alkyl or aryl halide compound, and
- (b) thereafter, maintaining the reaction mixture at a temperature of from about 20.degree. to about 50.degree. C for a period of from about 1/2 to about 120 hours.
Parent Case Info
This is a division of application Ser. No. 529,760, filed Dec. 5, 1974, now U.S. Pat. No. 3,974,242, which in turn is a Continuation-in-part of application Ser. No. 369,171, filed June 12, 1973, now abandoned.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
2909446 |
Redfarn |
Oct 1959 |
|
3869294 |
Lanier et al. |
Mar 1975 |
|
Divisions (1)
|
Number |
Date |
Country |
Parent |
529760 |
Dec 1974 |
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Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
369171 |
Jun 1973 |
|