一种非离子型水性环氧树脂乳液的制备及防腐性能研究

Preparation of a nonionic waterborne epoxy resin emulsion and study on its anticorrosion property

在三氟化硼乙醚的催化作用下,以聚乙二醇PEG-2000与环氧树脂EP-51合成了一种非离子型环氧乳化剂。将该乳化剂与Span-60复配,以EP-20环氧树脂为基础,通过相反转工艺制备了水性环氧树脂乳液。探讨了制备乳化剂时的反应物配比、催化剂用量、反应温度和反应时间对乳液粒径及稳定性的影响,确定了适宜合成乳化剂的工艺条件为:EP-51与PEG-2000物质的量比1.0∶1.5,催化剂0.50%(质量分数),反应温度90~100℃,反应时间3 h。将所制备的水性环氧树脂乳液与填料——含氟烯烃聚合物混合制成涂料,并与水性胺类固化剂反应成膜,研究了环氧树脂与固化剂不同配比及填料用量对涂层疏水性和防腐性能的影响。结果表明,当环氧值与胺值之比为1.0∶1.33,填料质量分数为5.0%时,所得涂膜的静态水接触角为115.0°,具有良好的耐蚀性。

A nonionic epoxy emulsifier was synthesized with polyethylene glycol PEG-2000 and epoxy resin EP-51 under the catalysis of boron trifluoride diethyl etherate,and then blended with Span-60 to prepare a waterborne EP-20 epoxy resin-based emulsion via phase inversion process.The effects of the reactants’proportions,catalyst dosage,temperature,and time for synthesizing the emulsifier on the particle size and stability of the emulsion obtained therewith were discussed.The suitable synthesis conditions were determined as follows:molar ratio of EP-51 to PEG-2000 1.0:1.5,mass fraction of catalyst 0.50%,reaction temperature 90-100℃,and reaction time 3 h.The emulsion was further mixed with the fluorinated olefin polymer filler to form a coating by reaction with a waterborne amine curing agent.The effects of the ratio of epoxy resin to curing agent and filler amount on the coating’s hydrophobicity and corrosion resistance were studied.The results showed that the coating obtained with 5.0wt.%of filler at a ratio of 1.0:1.33 between epoxy value and amine value had a static water contact angle of 115.0°and good corrosion resistance.