减反射涂层用含氟超支化聚氨酯丙烯酸酯的合成及其性能

Synthesis and properties of fluorine-containing hyperbranched polyurethane acrylates for reflectance-reducing coating

采用异佛尔酮二异氰酸酯(IPDI)、四氟丙醇(TFP)与三羟甲基丙烷(TMP)合成了一种含氟二元醇F-TMP,并将其作为扩链剂对超支化聚氨酯丙烯酸酯(PUA)改性,合成了一系列用于减反射涂层不同氟含量的超支化聚氨酯丙烯酸酯(FPUA)树脂。采用傅里叶红外光谱(FT-IR)对FPUA的结构进行了表征,并对固化过程中的双键转化率进行了固化动力学监测。结果表明:氟元素有效地接入了FPUA树脂中,其双键转化率与光固化涂料的初始粘度有关。进一步测试了光固化涂层的光学性能、附着力、硬度、柔韧性、耐水性以及热稳定性。结果表明,氟改性后涂层综合性能得到显著改善,耐水和耐化学品性能均有提高,当聚己二醇新戊二醇酯(PNA)与F-TMP的物质的量比为1∶0.5时,涂层的光透过率达到93.7%,光折射率为1.413,反射率2.11%,具有优异的光学性能,同时还具有最佳的热稳定性以及力学性能,附着力等级0,硬度可达91.5HD,柔韧性低至2 mm。

The fluorinated diol F-TMP was synthesized using isophorone disocyanate(IPDI),tetrafluoropropanol(TFP)and trimethylolpropane(TMP).As a chain extender,the F-TMP was employed to modify hyperbranched polyurethane acrylate(PUA).In addition,a series of hyperbranched polyurethane acrylate(FPUA)resins were synthesized for reflectance reduction coating with different fluorine contents.The Fourier infrared spectroscopy(FT-IR)was used to characterize the structure of FPUA and to monitor the curing kinetics of the double-bond conversion rate during the curing process.The results demonstrated that the elemental fluorine was efficiently accessed into the FPUA resin.The double-bond conversion rate was related to the initial viscosity of the UV cured coatings.The optical properties,adhesion,hardness,flexibility,water resistance and thermal stability of the UV cured coating were further tested.The comprehensive performance of the coating was significantly improved after fluorine modification,and the water and chemical resistance were improved. When the molar ratio of polyhexyle ne glycol neopentylglycol(PNA)to F-TMP was 1:0.5,the optical transmittance ofthe coating reached 93.7%,with a photorefractive index of 1.413 and a reflectance of 2.11%,providing excellent optical properties.Meanwhile,the coating had the best thermal stability and mechanical properties,with adhesion class 0,hardness up to 91.5 HD,and flexibility as low as 2 mm.