水性聚氨酯/聚甲基丙烯酸甲酯杂化乳液的合成

用异佛尔酮二异氰酸酯(IPDI)、聚丙二醇(PPG)和二羟甲丙酸(DMPA)合成了水性聚氨酯分散体(WPU),讨论了PPG摩尔质量,NCO/OH及PPG/DMPA比例对WPU乳液和涂膜性能的影响。以WPU为种子与甲基丙烯酸甲酯进行乳液聚合制备杂化乳液,研究了不同PU/PMMA物质的量比例对杂化乳液及涂膜性能的影响,并采用TEM对WPU及杂化乳液粒子进行了表征。结果表明,在以PPG1000为原料,NCO与OH物质的量比为1.4∶1,PPG与DMPA物质的量比为1∶0.8条件下制备的WPU杂化乳液,随着PMMA比例增加,杂化乳液的稳定性和成膜性变差,聚合物膜断裂伸长率降低,但铅笔硬度、耐水性及耐乙醇性均得到了改善。

Preparation of waterborne polyurethane/poly(methyl methacrylate) hybrid emulsion

The waterborne polyurethane dispersion(WPU)was prepared by using isophorone diisocyanate(IPDI),poly(propylene glycol)(PPG) and dimethylol propionic acid(DMPA) as monomers.The effects of PPG molar mass molar,ratio of NCO/OH and PPG/DMPA on the properties of the WPU emulsions and their films were discussed.The seeded emulsion polymerization was carried out between the seed emulsion WPU and methyl methacrylate and the hybrid emulsion was obtained.The effect of PU/PMMA molar ratio on the hybrid emulsions and their films were investigated.The morphology of WPU and PU/PMMA particles was analyzed by TEM.The results showed that stability of the emulsion and film formability were worse and elongations at break of polymer films were decreased,but the pencil hardness,water resistance and ethanol resistance were improved with the increasing of PMMA molar ratio of hybrid emulsion using WPU prepared at the conditions as followed: PPG1000 as raw material,molar ratio of NCO to OH 1.4∶ 1,molar ratio of PPG to DMPA 1∶ 0.8.