GB1100914A - Production of amide or ester interpolymers - Google Patents

Abstract

Amides or alkyl or hydroxyalkyl esters of a ,b -ethylenically unsaturated carboxylic acids are copolymerized with at least one other ethlenically unsaturated monomer in the presence of a peroxy-carbonate catalyst having the formula <FORM:1100914/C3/1> or <FORM:1100914/C3/2> or <FORM:1100914/C3/3> wherein R is either a tertiary alkyl radical having up to about 8 carbon atoms or a tertiary aralkyl radical whose alkyl moiety has up to about 8 carbon atoms, R1 is an alkyl radical of up to about 8 carbon atoms, an aryl radical, an aralkyl radical or an alkoxy alkyl radical, and R2 is an alkylene radical of up to about 12 carbon atoms or an oxaalkylene radical of up to about 10 carbon atoms, said radicals if desired containing substituents (e.g. nitro, halogen, ether or hydroxyl groups) inert to the reaction conditions, the temperature being at least about 200 DEG F. during the major part of the polymerization. (The term "alkyl" is used herein to include cycloalkyl radicals.) The peroxycarbonate may be used in combination with other catalysts such as di-t.-butyl peroxide, t.butyl hydroperoxide and azobisisobutyronitrile. Amide monomers specified are acrylamide, methacrylamide, itaconic acid diamide, a -ethyl-acrylamide, crotonamide, maleamic acid and esters, maleuric acid and esters and N-n-butoxymethyl acrylamide. Preferred esters are those of acrylic or methacrylic acid containing up to 12 carbon atoms in the alkyl or hydroxyalkyl group; also suitable are esters of ethacrylic, crotonic, maleic, fumaric and itaconic acids. Suitable comonomers include acrylate esters, styrene, vinyl toluene, acrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid, butadiene, 2-chlorobutene, a -methylstyrene, a -chlorostyrene, 2-chlorobutadiene, 1,1-dichloroethylene, vinyl acetate and butyrate, allyl chloride, dimethyl maleate, divinylbenzene, diallyl itaconate and triallyl cyanurate. Polymerization is generally effected in solution, optionally in the presence of a chain transfer agent, e.g. dodecyl mercaptan; suitable polymerization solvents include n- or isobutanol and mixtures thereof with xylene or aromatic naphtha. The amide polymers may be alkylolated by reaction with an aldehyde (e.g. formaldehyde, acetaldehyde or butyraldehyde) and, if desired, some or all of the alkylol groups may be etherified with an alcohol; alternatively an N-alkylol amide monomer may be used in the polymerization process. The polymer solutions obtained may be combined with pigments (e.g. titanium dioxide), fillers &c., and used for coating substrates, e.g. steel, aluminium or tin plate, the coatings being curable by baking.ALSO:Polymers obtained by copolymerising amides or alkyl or hydroxyalkyl esters of a , b -ethylenically unsaturated carboxylic acids in solution in an organic solvent and in the presence of certain peroxy carbonate catalysts (see Division C3) are suitable for coating metal substrates, e.g. steel, aluminium and tin-plate. The amide polymers may have amide groups alkylolated by reaction with an aldehyde and the alkylol groups may be optionally etherified with an alcohol. The polymers can be admixed with the usual additives such as pigments and fillers. The coatings can be cured by baking at 150 DEG -300 DEG F for from 10 to 45 minutes. In Examples, coatings on tin-plate were obtained using an acrylamide/styrene/ethyl acrylate/methacrylic acid copolymer obtained by solution polymerisation in an n-butanol / aromatic naphtha solvent, and on aluminium using an acrylamide/styrene/ethyl acrylate/methacrylic acid/ acrylonitrile copolymer obtained by solution polymerisation in an n-butanol/xylene solvent; both these polymers had amide groups methylolated with formaldehyde and further etherified with n-butanol, and were pigmented with titanium dioxide in a 1:1 weight ratio.