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Monoand bis(pentafluorosulfur)-substituted diacetylenes were thermally polymerized in both the bulk liquid and vapor phases at temperatures between 25 and 80 °C. The polymer formed in the liquid phase at 25 °C with SF5Cs=CC=CH was insoluble, while the polymer derived from SF5C^CC^CSF5 at 80 °C was soluble in fluorinated solvents. The vapor phase polymerization of both monomers occurred at 25 °C; the rate of polymerization of SFsC=CC^CH was rapid compared to SF5C^CC^CSF5. The newly formed polymers were characterized by a variety of spectroscopic and physical property measurements.

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SynopsisElucidation of mechanisms operative in thermal oxidative degradation of hexafluoropropene oxide derived polyethers and the effect of metals on these processes are reported. Thermal oxidative instability of a commercial fluid, at moderate temperatures (550'F), was found to be due to the presence of -3% of thermooxidatively unstable chains believed to be hydrogen terminakk treatment at 6 5 0 ' F in oxygen volatilized these chains by unzipping. The resultant fluid was unaffected by oxygen at 650'F and by M-50 and Ti(4A44Mn) alloys at 600'F in oxidizing atmospheres. M-50 alloy catalyzed the degradation of the hydrogen-terminated chains below and at 600'F, but after completion of this process did not affect the remainder of the fluid at these temperatures. A t 650'F a chain scission process promoted by the metals constituting the alloy, or their oxides or fluorides, came into play. Ti(4Al,4Mn) alloy in the presence of CF3COF and COFz species, formed via decomposition of the hydrogen-terminated chains, degraded poly(hexafluoropropene oxide) fluids at 550'F by chain scissions.

Five phosphate esters - tri-p-tolyl phosphate, tributyl phosphate, tris(1,3-dichloro-2-propyl)phosphate, tris(2,3-dibromopropyl)phosphate, and tris(2-chloroethyl)phosphate- were subjected to thermal oxidative degradation in air at 370 degrees C. Degradation mechanisms were postulated and the toxic hazards assessed based on the volatiles produced. Tri-p-tolyl phosphate was found to undergo only minimal degradation; the other compounds were decomposed extensively. Butene was the main product formed on tributyl phosphate decomposition; hydrogen halides and halogenated C2- and C3- species were the main products formed by the halogenated phosphate ester. In the case of tris(1,3-dichloro-2-propyl)phosphate acrolein, not hydrogen chloride, presented the major toxic hazard.

Pyrolyses of B‐triamino‐N‐triphenyl‐, B‐triamino‐N‐trimethyl‐, and B‐trianilino‐borazines were performed between 150 and 300°C. Initial stages of degradation were accompanied by liberation of ammonia in addition to the expected aniline or methylamine; this was most pronounced for the methyl borazine. Aniline elimination proceeded more readily with the B‐anilino than the B‐amino isomer. Data obtained support a ring opening mechanism resulting in telomerizaton accompanied by aniline liberation and formation first of singly then doubly bridged dimers and finally doubly bridged tetramers. Thermal exposure up to 1000°C failed to give pure boron nitride; carbon was invariably retained.

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