PRODUCTION OF POLYFORMALDEHYDE BY RADIATION-INDUCED POLYMERIZATION OF TRIOXANE
A study was made of the preparation of polyoxymethylene by the solid- state gamma radioinduced polymerization of trioxane. The yield and viscosity of the polyoxymethylene were determined as a function of temperature, irradiation dose, dose rate, and trioxane crystal size. In the 20--115 deg C range at a constant irradiation dose (Co/sup 60/ source, 0.54 Mrad) and constant dose rate (100 r/sec), the yield of polyoxymethylene increased with temperature to reach a maximum at the melting point, but the ln n of the polymer decreased with temperature from 0.82 at 20 deg C to 0.08--0.15 at 56 deg C. Polymerization did not take place at 0 to --198 deg C. Polymer yield increased with the integral irradiation dose and trioxane crystal size; the highest yield was 60% for large trioxane crystals at 0.54 Mrad, 100 r/sec, and 56 deg C. The ln n of the polymer increased with irradiation dose only between 0.24 and 0.36 Mrad, then sharply decreased, probably owing to polymer degradation at higher irradiation doses. Large trioxane crystals yielded a crystalline polymer that can be separated into individual fibers; small trioxane crystals yielded a powdery polymer. Post polymerization, which was observed in the irradiated trioxane, indicated that the radiation polymerization is free-radical in mechanism. Inhibition of trioxane polymerization in the presence of a free-radical polymerization inhibitor (hydroquinone and carbon tetrachloride) also indicated a freeradical polymerization mechanism. The polymer has a melting point of 178 -- 180 deg C. A thermomechanical curve is given. (AID Press)
- Research Organization:
- Originating Research Org. not identified
- NSA Number:
- NSA-18-017911
- OSTI ID:
- 4055113
- Journal Information:
- Plasticheskie Massy, Journal Name: Plasticheskie Massy Vol. Vol: No. 12
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
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PROCESS FOR THE PRODUCTION OF POLYFORMALDEHYDE
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ALKENES
CARBON TETRACHLORIDE
CATALYSIS
CHEMICAL REACTIONS
CHEMISTRY
COBALT 60
CONFIGURATION
CRYSTALS
DECOMPOSITION
DIAGRAMS
EFFICIENCY
FIBERS
FORMIC ACID
FREE RADICALS
GAMMA RADIATION
GRAIN SIZE
IRRADIATION
LOW TEMPERATURE
MEASURED VALUES
MECHANICAL PROPERTIES
MELTING POINTS
METHANE
METHYLENE
OXIDES
PHENYL RADICALS
POLYMERIZATION
POLYMERS
POWDERS
PREPARATION
QUINONES
RADIATION CHEMISTRY
RADIATION DOSES
RADIATION SOURCES
RADIOLYSIS
SEPARATION PROCESSES
SOLIDS
TEMPERATURE
TRIOXANE
VARIATIONS
VISCOSITY