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The epoxy resin has excellent physical and mechanical properties, electrical insulation properties , chemical resistance performance and bond performance characteristics , are widely used in various fields . But commonly used solvent-based epoxy resin is difficult to achieve due to high volatile organic compounds (VOC) content requirements of the green , so the research and development of water-based epoxy resin has an extremely wide range of applications . This article unsaturated fatty acids prepared by modifying the epoxy resin and epoxy ester , and acrylic monomers are further introduced by grafting method , and dispersed to obtain an ambient curing one - component aqueous epoxy resin emulsion , a variety of factors affect the product performance , and to determine the optimal experimental formula and process conditions . The experiments show that : during the preparation of the epoxy ester , it is found that unsaturated fatty acids in the type and amount of decisive effect on the product performance . The appropriate reaction conditions : selection of linolenic acid and epoxy resin E-20 reaction molar ratio of 4:1 ; ring-opening reaction temperature of 120 ° C , the amount of catalyst was 4% ; esterification reaction using the reflow process , the choice of the organic tin catalyst , added in an amount of 0.1 % , 200 ° C for 6 h . Radical polymerization in the process of preparing an aqueous epoxy resin emulsion , the greatest impact on product . The reaction using the grafting method ; amount of monomer with the epoxy ester ratio of 1:1 ; hard and soft monomer ratio of 2:3 ; system an acid value of 30 to 40 mg KOH · g -1 ; optional triethylamine as neutralizing agent , by 110% , and; suitable speed added to the aqueous dispersion , can be obtained after the solid content of 40 ~ 50% of the epoxy resin emulsion , and the emulsion and coating to achieve optimal performance . Using Fourier transform infrared spectroscopy analyzer ( FTIR ) , differential scanning calorimetry instrument ( DSC ) , transmission electron microscopy (TEM) polymers were characterized using a Malvern particle size analyzer test emulsion particle size and its distribution . The FTIR spectra show that E-20 and linolenic acid in the ring opening and esterification reaction , and further, grafted with acrylic monomers ; DSC curve shows that the polymer has two distinct glass transition temperature , were -0.8 ℃ and 45.3 ° C; particle size distribution test The average particle size was 77.8nm, PDI was 0.118 . TEM results further confirmed that the emulsion of the nano - sized spherical structure, diameter of about 70 ~ 80nm, the better the performance of the various stable .
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