A method for the production of polymethacrylsaeureimiden and of copolymers of the methacrylsaeureimide

摘要

Dimethacrylimide polymers are made by heating a polymer containing methacrylamide and methacrylic ester units to a temperature of between 110 DEG and 220 DEG C. in the presence of water or an alcohol containing at least two hydroxyl groups, e.g. monoethylene, diethylene, triethylene, propylene and trimethylene glycols and glycerol. Methacrylic esters specified are the C1-C6 alkyl and cycloalkyl methacrylates. The methacrylamide employed may be N-mono-substituted by a C1-C6 alkyl and cycloalkyl groups. The copolymers may also contain up to 20% of a further monomer, e.g. acrylonitrile, methacrylonitrile, ethyl acrylate, styrene and vinyl and vinylidene chlorides. The process may be carried out by copolymerizing the monomers in water or a polyhydric alcohol followed by heat treatment of the resulting copolymer whilst still in the polymerization medium. The examples describe the copolymerization of: (1) methyl methacrylate and methacrylamide in an aqueous medium containing potassium persulphate and ethylhexyl thioglycoleate, followed by the heating of the resulting copolymer dispersion, (2) as in (1) but with the addition of magnesium carbonate, (4) methyl methacrylate and methacrylamide in an aqueous medium containing sodium sulphate benzoyl peroxide and partially saponified polyacrylonitrile to yield a pearl polymer which is then heated in aqueous suspension, (5) butyl methacrylate and methacrylamide in an aqueous medium containing potassium persulphate, followed by heating of the resulting copolymer in its aqueous phase, (6) styrene, methyl methacrylate and methacrylamide in an aqueous medium containing potassium persulphate, followed by heating of the resulting copolymer dispersion, (7) methyl methacrylate, ethyl acrylate and methacrylamide by the process described in (1) with subsequent heating of the resulting dispersion, and (11) methacrylamide and methyl methacrylate in an ethylene glycol medium containing potassium persulphate, followed by heating of the resulting copolymer dispersion.