| abstract |
Graft copolymers are made by dissolving a polyalkylene oxide or glycol in at least one monomer, which is then polymerized by the action of a free-radical catalyst and/or actinic light. Monomers specified are vinyl acetate, propionate, butyrate and benzoate, methyl, ethyl, propyl and isopropyl acrylates and methacrylates, and mixtures of such monomers with one another or with other polymerizable compounds, e.g. acrylic, methacrylic and crotonic acids, dimethyl maleate and dibutyl fumarate and itaconate. Polyalkylene oxides and glycols specified are polyethylene and polypropylene glycols, copolymers of ethylene oxide with propylene oxide, 1:2-epoxybutane, isobutylene oxide and/or styrene oxide, polyalkylene glycols esterified or etherified at one or both ends with acetic, propionic or butyric acid or methanol or butanol, the condensation product of ethylene oxide with nonyl phenol and the condensation product of propylene oxide with tributyl phenol, polyalkylene glycols substituted at one or both ends by mono or polyamines, e.g. ethylene diamine, polyalkylene glycols substituted at one or both ends of the chain by carboxylic or sulphonic amide groups, and the reaction product of polyethylene glycol and p-phenylene diisocyanate. Polymerization catalysts specified are acetyl, benzoyl and lauroyl peroxides, a benzoyl peroxide/benzoin mixture and azodiisobutyronitrile. The polymerization may be carried out in bulk or in solution in a solvent such as methanol or methyl acetate. In an example (7) a graft copolymer of vinyl acetate crotonic acid and polyethylene oxide is dissolved in aqueous ammonia. Specification 874,130 is referred to. |