蒽醌型蓝色扩链剂及其PUA共聚物乳液的制备与性能

Preparation and Properties of an Anthraquinone Blue Chain Extender and Blue Polyurethane-acrylic Latex Prepared Using the Chain Extender

首先以1-甲氨基-4-溴-蒽醌和2-氨基-2-甲基-1,3-丙二醇为原料,通过取代反应合成了蒽醌型蓝色扩链剂1-(1,1-二(羟甲基))乙氨基-4-甲氨基蒽醌(HMEMAQ),并将其与N,N-二(2-羟乙基)丙烯酰胺作为扩链剂合成出聚氨酯预聚体,然后经与甲基丙烯酸甲酯和丙烯酸丁酯的接枝乳液共聚合制备出了性能稳定的共聚型蓝色聚氨酯-丙烯酸酯共聚物(PUA)乳液.然后用1H-NMR、FTIR、UV-Vis吸收光谱、粒度和电位分析、氙灯老化等方法对HMEMAQ的化学结构、PUA乳液及乳胶膜的性能进行了表征.研究发现,在N2气氛下,用偶氮类AIBN作为引发剂可以有效避免PUA乳液合成过程中生色基团的氧化变色现象.当AIBN用量达到不饱和单体的2 wt%时,接枝反应的单体转化率可达到99.9%.HMEMAQ用量对乳液的胶体性质和单体转化率没有明显影响.PUA聚合物和HMEMAQ的UV-Vis吸收光谱保持一致,最大吸收波长均为640.8 nm.与具有相同生色基团的共混型蓝色PUA乳胶膜相比,共聚型PUA乳胶膜的耐光色牢度和耐溶剂色牢度有明显的提高.

A new blue chain extender, l-（1,1-bis（hydroxymethyl） ） ethyl amino-4-methylamino anthraquinone （HMEMAQ） was synthesized using 1-methylamino-4-bromo-anthraquinone and 2-amino-2- methyl-1 ,3-propanediol as raw materials by substitution reaction, and then the polyurethane prepolymer was prepared using HMEMAQ and N,N-bis（2-hydroxyethyl） acrylamideas chain extenders. After that, the covalently blue polyurethane-acrylate copolymer （PUA） emulsion was fabricated through the copolymerization of polyurethane prepolymer with methyl methacrylate and butyl acrylate. The chemical structure of HMEMAQ and the properties of PUA emulsions and their latex films were characterized by 1H-NMR, FTIR, UV-Vis spectra, size and zeta potential analysis, xenon arc aging testing and so on. Results showed that, under nitrogen atmosphere,the color fading of emulsions could be avoided when AIBN was used as initiator during the fabrication of PUA emulsions. When the AIBN amount was equal to 2 wt% based on the unsaturated monomers, the conversion of unsaturated monomers reached 99.9%. The unsaturated monomer conversion and the colloidal properties had no obvious change with the increase of the HMEMAQ amount. The A max value of the PUA film and HMEMAQ was the same at 640.8 nm,indicating the same color of them. Comparing with the non-covalently blue PUA film which had the same chromophore, the covalently blue PUA film exhibited obvious improvements both in light fastness and solvent fastness.