【作者】 谭卓华；

【导师】 梁亮；

【作者基本信息】 广东工业大学 ， 应用化学， 2008， 硕士

【摘要】 醋酸丁酸纤维素是天然高分子纤维素的酯化产物。由于醋酸丁酸纤维素具有较好的耐水性、耐候性、成膜柔韧性、高度透明性以及能稳定金属的定向排布等优点,因此醋酸丁酸纤维素可以作为主要成膜物,广泛应用于各种木器涂料、玻璃涂料、塑料涂料以及透明金属清漆中。但醋酸丁酸纤维素的涂层较软、耐划伤性能差、耐溶剂性能不甚理想,加上其成膜需要耗费大量溶剂,不利于环境保护,所以针对醋酸丁酸纤维素的改性是必要的。本研究首先用溶液聚合的方法合成了丙烯酸酯接枝醋酸丁酸纤维素的水溶性树脂,有效地改善了醋酸丁酸纤维素涂层的使用性能,并讨论了引发剂的用量、丙烯酸酯单体的比例、反应温度等因素对合成及其性能的影响。研究结果表明:采用混合单体连续滴加的加料方式、反应温度为85℃、搅拌速度为150r/min～200r/min、反应3h可以顺利合成丙烯酸酯改性醋酸丁酸纤维素的水溶性树脂,单体转化率在96%以上。当AA的用量为12%,软硬单体比例为1/1.5时,改性后的树脂硬度从H提高到4H,对玻璃的附着力从4级提高到0级,具有高度的透光率和良好的水溶性。其次,本研究还利用马来酸酐易开环反应的特性,在均相体系中合成了马来酸酐改性醋酸丁酸纤维素。改性后的树脂在紫外(UV)光辐射下交联固化,可得到无溶剂挥发的100%固含量的光固化涂层。研究结果表明,用马来酸酐改性后的醋酸丁酸纤维素,在活性稀释剂的适当配比下,其光固化涂层硬度可达4H、附着力0级(玻璃)、耐丙酮可达400次以上。进而在亲水性溶剂的存在下,进一步得到水分散性光固化的改性纤维素酯。在单体SR610的一定比例下,可以得到耐水性96h的优异涂层。更多还原

【Abstract】 Cellulose acetate butyrate (CAB) is product of esterification by natural fiber. As CAB has features in preferable water resistant, weather resistant, flexility, high transparency and can stabilize the orientation arrangement of the metal, so it could apply in kinds of wood coating, glass coating, plastic coating and transparent varnish as main film former. But the CAB coating is so soft and the solvent-resistance and the scratch-resistance are not so excellent. Besides, it may cost so large amount of solvents to form film that it is unfavorable to environment. So it is necessary to modify the CAB.In this paper, firstly, the acrylate grafted with CAB could be prepared by solution polymerization as a water-soluble resin. The product could effectively improve the service performance of the CAB coating and many factors such as initiator content, the ratio of soft/hard monomer, reaction temperature, etc, on the polymerization and property of product were discussed. The results show that the CAB modified by acrylates could be favorably prepared and the conversion rate of monomers is greater than 96%, when the continuous feeding is used, the reaction temperature is 85℃, the stirring rate is 150r/min~200r/min and the reaction time is 3h. When the content of acrylic acid is 12%, the ratio of soft/hard monomer is 1:1.5, it could get the best properties of the modified resin. The hardness could reach 4H from H, the adhesion to glass is zero degree from four degree and the coating is highly transparent and excellently water-soluble.Besides, to make full use of the open-loop behavior of the maleic anhydride, the maleic anhydride grafted with CAB is synthesized in homogeneous system. The modified resin is crosslinked and then a non-solvent, 100% solid content UV-cured coating is obtained. The results show that under the suitable proportion of reactive diluents, the hardness, the adhesion to glass and the solvent-resistance of the UV-cured modified-CAB coating are respectively 4H, 0 degree and more than 400 times. Moreover, the waterborne UV-cured resin is also received. When SR610 reaches at a certain proportion, a water-resistant 96h coating could be obtained.更多还原