Polystyrene radiation-induced polymerization

When the 2-methyltetrahydrofuran and n-butylchloride glasses with about 10 mole-% of styrene in them are irradiated to the dose of 1 X 107 rad, polystyrene is obtained only from the latter glass, though the polymer yield is low (1 2%). This indicates that radiation-induced polymerization occurs in the glass where the cation radicals are formed by the radiation. The experimental results of the polymerization in glass matrices are consistent with the previous report that the radiation-... 

When a miniemulsion polymerization initiated by Co y-rays was carried out to synthesize polystyrene particles [65], the dose rate and total dose were each found to aflect the size of the latex particles. Y-Hke branched surfactants were synthesized and used for y-ray miniemulsion polymerization at room temperature [66] moreover, 2wt% polyurethane used as a hydrophobe for the miniemulsion polymerization of styrene was suflBdent to ensure a shelf-Hfe of one year for the miniemulsion [67]. In both cases [66, 67], the particle size and distribution were preserved throughout the polymerization. The copolymerization of styrene with l-vinyl-2-pyrrolidone as a polar monomer in the presence of dodecane in the oil droplets, also led to the production of nanocapsules [68]. Subsequent H NMR spectroscopic analyses showed that graft copolymers had been obtained via radiation-induced polymerization, rather than random copolymers. Hence,... 

Quian Z, Zhicheng Z, Yun C (2008) A novel preparation of surface-modified paramagnetic magnetite/polystyrene nanocomposite microspheres by radiation-induced miniemulsion polymerization. J Colloid Interface Sci 327 354-361... 

It is now well established that organic polymers are rather more sensitive to various ionizing radiations. In a recent study (23) it has been shown that the irradiation of polystyrene films by 20 MeV 28gi beam results in ion-induced modifications of the sample because a significant quantity of H and C nuclei is released when the beam dose is increased above 1012 ions cm 2. Similar effects of erosion of H and C profiles of plasma-polymerized hexamethydisilasene (HMDSN) thin... 

Ballantine (4) observed that the y-induced emulsion polymerization of styrene is about 100 times faster and yields higher molecular weights (up to 2 X 10 ) than the y-induced bulk polymerization. He explains the large difference in reaction rates by the high radical yield (G/ value) of water, as compared with the G/j value of styrene. An over-all activation energy of 3.7 kcal. per mole was calculated from the temperature dependence of the reaction. Allen et al. (1) prepared and grafted polystyrene and poly (vinyl acetate) dispersions under the influence of y-radiation. Mezhirova et al. (28) found a temperature-independent reaction rate of the y-induced emulsion polymerization of styrene. 

Wang X., Zhang Z., Preparation of polystyrene latex particles by gamma-rays-induced emulsifier-free emulsion polymerization, Radiat. Phys. Chem., 2006,75,1001-1005. 

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