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In epoxy resin applications, the curing agent is an important and indispensable component, which together with the epoxy resin to play a decisive role in the physical properties of the cured product. This topic is for the hot and humid weather of the South to develop a new curing agent and epoxy resin with the use of Advanced Wood Coatings. Selected according to the process requirements, the modified fatty amines as raw materials for synthesis of the curing agent. Aliphatic polyamines containing two active hydrogen atoms that the hydrogen of the primary amine and secondary amine hydrogen, and higher activity of the former, the reaction with the epoxy resin at room temperature is heated, a curing shrinkage stress, so that the curing properties brittle, easily cracking, so commonly used capping agent closed a portion of the primary amine hydrogen, to reduce the activity of the multi-amine curing agents. Epoxy resin (E-51) as a chain extender to further improve the compatibility between the curing agent and epoxy resin are used in the curing agent at the same time. This thesis respectively single epoxy-based compounds, acrylic acid esters of diethylene triamine (DETA), endcapped modified. The cured coating glass transition temperature measured by DSC, and the further determination of the curing time, the water resistance of the paint film, the tensile strength, elongation at break, adhesion, gloss, and other properties, through the different capped The comparative analysis of the various indicators of the performance of the cured product obtained by the modified by the capping agent to determine the optimal glycidyl versatate glycerides (E10). For the existing problems in practical applications, we adjust the curing agent formulations and synthesis technology came to the conclusion: 1, n (E10): n (DETA): n (E-51) = 1.2:1:0.3 solid content 65%; 2, the first step of the reaction temperature is capped: Addition second step: from 75 to 80 ° C; 3, in the course of the reaction dropwise feeding, versatic acid glycidyl ester dropwise to 65 to 70 ° C; plus time for 30min; 4, the reaction time of the first step capped: 2H; second step Addition: 2H, resulting curing agents with epoxy resin to obtain the best properties of cured. In addition, by adjusting the solvent, the amount of curing agent, methyl methacrylate was added to improve the gloss, the measures to further optimize the formulations using nonylphenol improve cure speed. Experimental results show that: 1, using the formulations mixed solvent in the resultant film properties; 2, in accordance with an amine equivalent weight and the epoxy equivalent 1.0:1.0 curing agent and an epoxy resin with an epoxy group and can not completely reacted, the ratio of between 1.0:1.0-1.1:1.0, better performance of the cured product; 3, the amount of methyl methacrylate, 5% on the gloss will be improved to some extent; 4, nonylphenol added causes shorten the curing time is about two hours, but will cause the paint film hardness becomes low.
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