紫外光固化水性聚氨酯-含氟丙烯酸酯乳液的制备及其稳定性研究

以多异氰酸酯、丙烯酸羟乙酯(HEA)、多羟基含氟丙烯酸酯树脂、丁二酸酐(SAA)和三乙胺(TEA)等为主要原料,合成了紫外光固化的含氟WPUA(水性聚氨酯丙烯酸酯)乳液。采用红外光谱(FT-IR)法和核磁共振氢谱(1H-NMR)法对该产物结构进行了表征,并采用热重分析(TGA)法对产物热稳定性进行了研究。结果表明:当n(-NCO)∶n(TEA)=2∶0.5、n(-NCO)∶n(HEA)=2∶1.5、固含量为50%、剪切速率为2 000 r/min和剪切时间为25 min时,WPUA乳液具有较高的机械稳定性和冻融稳定性;此时WPUA涂膜的综合性能较好,其铅笔硬度为3H、柔韧性为1 mm、光泽度为125且水接触角为72°。

Study on preparation and stability of UV-curing waterborne polyurethane/fluorine-containing acrylate emulsion

With polyisocyanate,hydroxy ethyl acrylate(HEA),polyhydroxy fluorine-containing acrylate resin,succinic anhydride(SAA),triethylamine(TEA) as main raw materials,so an UV-curing fluorine-containing WPUA(waterborne polyurethane-acrylate) emulsion was synthesized.The product structure was characterized by FT-IR(Fourier transform infrared spectroscopy) and 1H-NMR(1H-nuclear magnetic resonance) methods,and product stability was also investigated by TGA(thermal gravimetric analysis).The results showed that the WPUA emulsion had better mechanical stability and freezing-thawing stability when molar ratio of n(-NCO)∶n(TEA) was 2∶0.5,molar ratio of n(-NCO)∶n(HEA) was 2∶1.5,solid content of emulsion was 50%,shearing speed was 2 000 r/min,and shearing time was 25 min.Here the WPUA film had better combination property because its pencil hardness was 3H,flexility was 1 mm,glossiness was 125,and water contact angle was 72°.