Vinyl acetate radiation-initiated polymerization

Monomers and Resins. Radiations such as 7 rays, ultraviolet light, and electron beams can initiate free-radical polymerization of vinyl monomers or unsaturated resins. Styrene, vinyl acetate, acrylonitrile, acrylates. 

At 20°C, the rate of polymerization of vinyl acetate initiated by y-radiation is substantially greater than that of many common monomers [1]. 

For example, compositions of 10 ml of a 3.75 gm per 100 ml aqueous solution of sodium dioctylsulfosuccinate (Aerosol OT or Manoxol OT) and 1.25 ml of vinyl acetate with small additions of sodium dihydrogen phosphate, after exclusion of oxygen by at least four degassings, were sealed in glass ampoules. The samples were exposed, at 15°C, to a Co source (100 curie). Conversion was nearly 75% after 30 min. Polymers of MW as high as 10 were formed. The polymers contained trapped free radicals capable of initiating graft polymerization with methyl methacrylate after removal from the radiation source [185]. 

An unusual free-radical polymerization of vinyl monomers utilizes ultrasound to both emulsify monomer and to create free radicals [7]. The ultrasound (at 20 kHz) acts on water to create hydrogen and hydroxyl-initiating radicals, an initiating system that bears resemblance to many radiation-induced polymerizations. The first claimed emulsion polymerizations by ultrasound were those of butyl acrylate and vinyl acetate [7]. In most cases it was observed that the particle... 

An extensive study has been made of the graft polymerization of vinyl monomers (e.g. methyl methacrylate, sodium vinyl sulphonate, 4-vinylpyridine, acrylamide, and acrylic acid) onto dissolving pulp and groundwood initiated by acetic acid and hydrogen peroxide. It is possible to predict accurately the extent of grafting and the properties of the graft copolymers. The effects of solvents on the radiation-induced grafting of vinylpyridines onto cellulose have been examined. ... 

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