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Cast and mold polymerization of organic glass by irradiation from fluid and soft gel prepolymers

✍ Scribed by Hiroshi Okubo; Fumio Yoshii; Sigeru Nishiyama; Kenzo Yoshida; Isao Kaetsu


Publisher
John Wiley and Sons
Year
1979
Tongue
English
Weight
448 KB
Volume
24
Category
Article
ISSN
0021-8995

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✦ Synopsis


Abstract

Casting and mold polymerization processes were investigated by means of γ‐irradiation of methyl methacrylate prepolymer systems containing some quantity of polyfunctional monomers. Some physical properties, such as supercooling tendency and temperature dependence of viscosity and relaxation time in fluid prepolymers, were measured and related to cast polymerization at low temperatures. It was found that free‐state casting with no frame or mold was possible using viscous states of prepolymer in the supercooled state. Furthermore, efficient mold polymerization using soft gel prepolymer was studied. That is, plastic soft gel prepolymer was prepared conveniently by irradiation of fluid prepolymer, then molded into spherical or nonspherical curved surface shapes, and curved by reirradiation. Polymerization and gelation behavior of soft gel prepolymer and penetration degree of prepolymer as a measure of plasticity of gel were studied in relation to prepolymer composition and irradiation condition.