Preparation And Properties Of Waterborne Epoxy Modified Acrylate Emulsion

Waterborne acrylate emulsions have been widely used in the field of waterborne architectural coatings due to their environmental friendliness,low cost,excellent film formation and ease of structural adjustment.However,ordinary water-based acrylates still have shortcomings in water resistance,chemical resistance,and heat resistance,and cannot meet the needs of the construction industry.The structure of the epoxy resin determines its excellent adhesion,corrosion resistance,thermal stability,mechanical strength and high reactivity,making it suitable for modifying acrylates to achieve complementary advantages and epoxy bonding.The branch modification retains the reactivity of the epoxy group,and increases the crosslinking density when the crosslinking is cured to form a film,so that the coating becomes a dense film and has excellent dielectric resistance.In this thesis,a semi-continuous seed emulsion polymerization method was used to graft epoxy resin(E-44)to modify acrylate to prepare an aqueous epoxy modified acrylate emulsion.The research contents are as follows:Acrylate was prepared by using semi-continuous seed emulsion polymerization method with butyl acrylate(BA),methyl methacrylate(MMA)and methacrylic acid(MAA)as monomers,and modified with epoxy resin(E-44).Monomer,synthetic epoxy grafted acrylate emulsion P(E-44/BA/MMA/MAA).The order of epoxy resin feeding,the pre-emulsification speed,the type and ratio of emulsifier,the functional monomer methacrylic acid,the stirring speed,the type and amount of initiator,the particle size and distribution of latex,mechanical stability,storage stability,The effects of epoxy equivalent,appearance,solid content and gel fraction.The results show that the epoxy resin feeding sequence significantly affects the emulsion epoxy equivalent;when the pre-emulsification speed increases,the emulsion particle size decreases;when the emulsifier SDS: OP-10 ratio increases,the emulsion particle size decreases;when the emulsifier LR-10: The proportion of LG-20 increases,the particle size of the emulsion decreases;when the proportion of emulsifier DNS86:Triton X-100 increases,the particle size of the emulsion decreases;when the content of functional monomer methacrylic acid MAA increases,the particle size of the emulsion Firstly,it decreases and then stabilizes;the stirring speed has no obvious effect on the particle size of the emulsion;when the content of the initiator increases,the particle size of the emulsion decreases first and then increases.When the epoxy resin feeding sequence E,the preemulsification rotation speed is 10000r/min,the reactive anionic emulsifier(DNS-86)is used in an amount of 2%,the MAA dosage is 1.1%,and the optimum stirring speed is 200r/min.When the content of the agent(APS)is 2%,the performance of the polymer emulsion is optimized.The composition and morphology of the polymer were characterized by FT-IR,TEM,DSC,TGA,GPC and contact angle,and the polymerization mechanism was studied by using Materials Studio molecular simulation software.The results showed that the reaction was graft polymerization.