| 摘要 |
An organic peracid is added to a nonionic latex of a polymer of a conjugated diene to form oxirane groups in the polymer. Specified polymers are those of butadiene and its mixtures with butene, styrene, methylstyrene, acrylonitrile, methacrylonitrile, esters of acrylic and methacrylic acid and vinyl chloride, polyisoprene, natural rubber, polyvinyl cyclohexene and copolymers of isoprene or vinyl cyclohexene with any of the above butadiene comonomers. Nonionic emulsifying agents used to form the latex include esters of sorbitol, sorbitan, mannitol, mannitan, polyglycerol, polyethylene glycols, a partial ester of a highly polymerized glycerol, a hydroxy alkyl ether of glycerol, sorbitol or mannitol, or an ethylene oxide adduct of a phenol or alcohol. Specified peracids are peracetic, performic, perphthalic and perbenzoic acids. The acid is usually buffered with sodium acetate. The by-product organic acid formed during the reaction may be neutralized, renewed by dialysis or removed by low temperature vacuum distillation. The epoxidized latex product may be mixed with a formaldehyde resin and cured. In Examples (3) 90 parts of epoxidized 50 butadiene-50 styrene copolymer latex and 10 parts ureaformaldehyde resin were cured at 150 DEG C. for half an hour as a film on glass and (4) 95 parts of epoxidized 33 butadiene-67 styrene copolymer latex and 5 parts melamine-formaldehyde resin were cured at 150 DEG C. for 15 minutes as a film on glass. Other curing agents specified are ethylenediamine, N-(hydroxyethyl)diethylenetriamine, m-xylylene diamine, piperidine, diethylamino propylamine, m-phenylenediamine, dimethylaminomethyl phenol, 4,41diaminodiphenyl sulphone, polyacrylic acid, diglycolic acid, trimelitic anhydride, maleic anhydride, adipic anhydride and boron trifluoride. |
