紫外光固化树脂膜的强度和耐醇性研究

制备了一系列紫外光固化树脂膜 ,并考察了光固化树脂、光敏剂、活性稀释剂对膜强度和耐乙醇性的影响 .发现用光固化的聚氨酯丙烯酸酯齐聚物制得的膜强度和柔韧性较好 ,但在各种浓度的乙醇水溶液中 ,膜的强度大大下降 .在光固化体系中加入过氯乙烯能显著提高膜的强度和耐乙醇性 ,共混膜可用作膜材料渗透汽化分离乙醇水溶液 .

一种车用新型紫外光固化阻燃涂膜的制备

制备了一种车用新型紫外光固化阻燃涂膜,其主要成分为丙烯酸酯低聚物(30%~70%)、活性稀释剂(15%~40%)、光引发剂(1%~6%)、附着力促进剂(1%~15%)以及流平剂和消泡剂(0.1%~1%)。其中的丙烯酸酯低聚物为含磷聚氨酯丙烯酸酯活性低聚物。该车用新型紫外光固化涂膜不仅附着力达一级,还避免了一般涂膜易燃的缺陷。

水性超支化聚氨酯丙烯酸酯的光固化膜性能

以甲苯-2,4-二异氰酸酯、丙烯酸羟丙酯、丁二酸酐、自制超支化聚酯为原料,合成了一种新型可紫外光固化的水性超支化聚氨酯丙烯酸酯,采用傅里叶变换红外光谱分析了其合成过程中基团的变化。固化膜热分析表明,随着超支化聚氨酯丙烯酸酯中端丙烯酸酯基含量的增加,热降解温度从171.0℃升高到238.9℃,玻璃化转变温由56.2℃升高到72.8℃;其力学性能测试表明,随着TDI.HPA含量的增加,硬度增加,而柔韧性和抗冲击强度都呈递减的趋势。

脂环族环氧有机硅预聚体的合成及光固化性能

用不同含氢量的PDMS-PHMS和4-乙烯基-1-环己烯-1,2-环氧为原料,通过简单的一步硅氢加成反应得到脂环族环氧有机硅预聚体。利用FT-IR和^(1)H-NMR对所合成的环氧基聚硅氧烷低聚物的结构进行了表征,结果表明,预聚体的成功合成。加入适量阳离子光引发剂,在紫外光照射下,环氧基聚硅氧烷预聚物发生阳离子聚合,快速固化成环氧基聚硅氧烷树脂薄膜。通过紫外透光率、热失重分析、接触角、铅笔硬度等对紫外光固化膜的性能进行了测试和表征。结果表明,水滴在涂层上表现出97°~116°的接触角,涂层的透明度超过90%。涂层在高达330.3~366.5℃仍保持稳定。结果证明制得的薄膜表面均匀透明,具有优良的耐热性、耐酸性、疏水性以及去油墨性能的涂层。

UV-curing of hyperbranched polyurethane acrylate-polyurethane diacrylate/SiO_2 dispersion and TGA/FTIR study of cured films

UV-curable hyperbranched polyurethane acrylate-polyurethane diacrylate/SiO2 dispersion （HBPUA-PUDA/SiO2） was prepared with isophorone diisocyanate （IPDI）, hyperbranched polyester Boltorn H20 （H20）, hydroxy-ethyl acrylate （HEA）, polyethyleneglycol （PEG-200）and nano-SiO2. The UV curing kinetics of the films was investigated by FTIR. The results show that the curing speed of the films increases with the adding of nano-SiO2 and decreases with the adding of PUDA due to the slower chain movement. The thermal stability of the HBPUA-PUDA/SiO2 films was studied by using thermogravimetric analysis coupled with Fourier transform infrared spectroscopy （TGA/FTIR）. The results show that all films exhibit two degradation stages located at about 320 and 440℃ corresponding to the degradation for hard segments of urethane-acrylate and the degradation for soft segment and polyester core. In addition, the results from the analysis of TGA/FTIR also indicate that the decomposition temperature of HBPUA-PUDA/SiO2 film is 15℃ higher than that obtained for pure polymer. The degradation mechanism was proposed according to TGA/FTIR results.