Low Temperature Curing Of Waterborne Amino-acrylate Automotive Coatings

This paper synthesized a large waterborne urethane acrylate monomers and acrylic monomers with other functional monomer emulsion was prepared by waterborne urethane acrylate emulsion,to a low temperature by introducing the solution with sodium bisulfite blocked isocyanate seal,single-component selfcrosslinking reaction,and finally get low-temperature curable aqueous amino-acrylic automotive paint.? Using six methylol melamine(HMM),acrylic acid(AA)as the starting material,1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride(EDCI)and Nhydroxysuccinimide imide(NHS)together as catalyst for the esterification reaction aqueous phase carbamic acrylate macromonomer.By infrared spectroscopy of synthetic amino acrylate macromonomer was characterized,respectively,and the amount of catalyst for esterification,the best reaction time,the optimum reaction temperature and six-methylol melamine(HMM)and acrylic acid(AA)is the most good reaction ratio were explored.The results showed that the catalyst 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride(EDCI)and Nhydroxysuccinimide(NHS)in an amount of reactant species HMM 2 times the amount,the reaction time was 22 h,the optimum reaction temperature is 15 ?,acrylic:HMM materials ratio of 1.4: 1 up to amino acrylate macromonomer conversion.? In amino acrylate macromonomer,methyl methacrylate,butyl acrylate and methacrylate,?-emulsion as the main raw material,synthetic water-based urethane acrylate emulsion.Study on the choice of emulsifier,emulsifier,aminobutyric acrylate macromonomer of gloss paint and the contact angle,the quality of methyl methacrylate and butyl acrylate ratio on film properties,?-armor based on acrylic emulsion properties.It reveals that active anionic emulsifier SR-10,in an amount of3% on monomers,urethane acrylate monomers in an amount of 8% to 10% and the mass ratio of methyl methacrylate and butyl acrylate is 2.0,?-the amount of methyl methacrylate monomer when the total mass of 1.5%,the best performance of emulsion and film,emulsion stabilizers,delicate,pan-blue light,the film smooth and bright.? With sodium bisulfite to prepolymer isocyanate capping reaction with an emulsion blended film by infrared spectroscopy analysis of a capped product bisulfite,sodium and explore the sodium bisulfite in an amount on the closure rate of the product by the DSC method deblocking temperature were determined,amino acrylates and ordinary varnish acrylic varnish performance testing and compared.Results Table Minya sodium bisulfate successfully blocked isocyanate a NCO group and its unblocking temperature 50 ~ 80 ?.Na HSO3 closed reaction rates on the large amount of n(NaHSO3): n(a NCO)= 1.2,the highest closing rate.Varnishes appearance amino acrylates excellent performance,the film formation,smooth,high gloss,storage stability of 30 ?,7d,attachment capacity 0,acid 5% HCl,48 h,Alkali5% NaOH,48 h,water 5d,the hardness of 2H,better than ordinary acrylate,to meet the performance requirements of automotive finishes.