Ymer N120改性非离子型水性环氧乳液的制备与性能研究

为克服当前水性环氧乳液的环氧基团含量和固含量低导致的涂料和涂膜性能差的缺点，本文从分子结构设计的角度出发，首先以聚乙二醇400（PEG400）为软段，制备了非离子型水性环氧（WEP）乳液；然后以侧基亲水扩链剂（Ymer N120）对其进行改性，合成了改性非离子型水性环氧（YWEP）乳液，研究了Ymer N120的用量对YWEP乳液和涂膜性能的影响.结果表明，WEP乳液的环氧基团含量（以环氧值表示）最高可达0.36,引入侧基亲水基团后YWEP乳液可在保持较高环氧值的条件下进一步将固含量由30%提高至52%,提高了73.3%.固化后涂膜的拉伸强度由57.3 MPa增大至64.8 MPa.腐蚀电流密度由7.97×10^-8 mA·cm^-2减小至9.99×10^-9 mA·cm^-2.综上所述，亲水基团由主链转移至侧基后可有效提高水性环氧乳液、涂料和涂膜的性能.

Preparation and properties of Ymer N120 modified non-ionic waterborne epoxy emulsion

In order to overcome the disadvantage of low content of epoxy group and solid in current waterborne epoxy (WEP) emulsion, polyethylene glycol 400 (PEG400) was used as soft section to prepare non-ionec WEP emulsion firstly. Then, the modified non-ionic waterborne epoxy (YWEP) emulsion was synthesized with the side hydrophilic chain extender (Ymer N120). The effects of the dosage of Ymer N120 on the properties of YWEP emulsion and paint film were studied. The results showed that the epoxy group content (represented by epoxy value) of the WEP emulsion could be increased as high as 0.36, and the solid content pof YWEP emulsion increased by 73.3% from 30% to 52% while maintaining the high expoxy value. After curing, the tensile strength of the film increases from 57.3 MPa to 64.8 MPa. The corrosion current density decreased from7.97E-8 mA*cm-2 to 9.99E-9 mA*cm-2. In conclusion, the transfer of hydrophilic groups from the main chain to the side group can effectively improve the properties of waterborne epoxy emulsions, coatings and coatings.