关键词: 含氟丙烯酸树脂, 阴极电泳涂料, 表面能, 低温固化, 腐蚀性能

Abstract:

Cationic fluorinated acrylic ester resin for cathodic electrodepositing （CED） coating and cationic blocked-diisocyanate TId were synthesized by the polymerization of isophorone diisocyanate （IPDI）, cationic triethanolamine （ TEOA）, ZonylTM and some other acrylic ester monomers, with 3,5-dimethylpyrazole （DMP） as the blocking agent. The compositions of the two products were then characterized using FT-IR spectra, and the curing behaviors of CED coating were analyzed by means of DSC and TGA. The results indicate that CED coating tends to crosslink at about 90 ℃. Moreover, the contact angle test of CED film shows that the fluorinated CED coating is an effective way to low-energy surface. Moreover, with the newly-designed cationic cross-linker TId, the thermal degradation of the fluorinated side chains in the CED resin was successfully avoided. The electrochemical impedance spectroscopy （EIS） of the fluorinated CED film reveals that the introduction of fluorinated acrylic ester helps to improve the corrosion resistance of the film.

Key words: fluorinated acrylic resin, cathodic electrodeposition coating, surface energy, low-temperature curing, corrosion resistance