The Synthesis Of Reactive Microgels And Their Application In Waterborne Coatings For High Speed Express

Reactive microgels with hydroxyl have been prepared via emulsion polymerization, in which partly saponificated undecylenic acid (UNA) emulsion was used as reactive emulsifier and the crosslinking structure of microgels was built up by not only the polymerization of triethylene glycol diacrylate (TEGDA), but the ring-opening esterification of glycidyl methacrylate (GMA) and UNA as well. When the saponification degree of UNA was 25.8~50.8% and its amount was 13.40~ 16.66% to that of the monomers, stable reactive microgels with hydroxyl were synthesized successfully. There was about 44.0-45.8% of GMA experiencing the ring-opening esterification reaction to produce a structure with hydroxyl ester and two double-bonds, and about 7% processing the ring-opening hydrolyzation to produce a structure with two hydroxyls. The BP (Back-Propagation) neural network was employed to analyze the relationship between the two reactions in building up the crosslinking structure of microgels. Compared with the one-stage method and the monomer post-added method, the monomer grads-added process was much more effective for producing stable microgels with higher crosslinking degree and the hydroxyls tended to distribute in the surface layer.Fluorinated reactive microgels with core-shell structure were synthesized with not only partly saponificated UNA emulsion, but also fluorinated-anionic /nonionic mixed emulsifier. Effects of the two emulsifiers on the stability, dispersion and morphology of microgels were studied. The behavior of fluorinated microgels in waterborne self-stratifying coatings was determined and the synthesizing conditions...