聚乙烯吡咯烷酮(PVP)和脲醛树脂(UF)包覆耐晒黄G的研究

用界面聚合法(以PVP为囊壁)和原位聚合法(以UF为囊壁)制备了耐晒黄G微胶囊.实验结果表明:当以Na2SO4为分离剂,其水溶液加入速度为20 mL/min,囊材含量为15％,分散剂浓度为2.5％时,得到的PVP包覆的耐晒黄G微胶囊性能最好,其平均粒径小于4 μm;而在酸性条件下,以NH4Cl代替有机酸做催化剂,控制酸化时间为4h,反应终点pH为1.5,固化温度为70℃,固化时间为2h时,得到的UF包覆的耐晒黄G微胶囊性能最好,其平均粒径达3.2 μm.

Studies on Cladding Light-Durable Yellow G with Polyvinylpyrrolidone and Urea Formaldehyde Resin

The light-durable yellow G microcapsules were prepared by interfacial polymerization method and in-situ polymerization processes in this article,using polyvinylpyrrolidone(PVP) and urea formaldehyde resin(UF) as cyst wall respectively.The experimental results show that the performance of the light-durable yellow G microcapsules cladded by PVP is best and the average particle size of them is smaller than 4 μm under the following parameters: with Na2SO4 as dispersing agent and the dropping speed of its water solution is 20 mL/min,the amount of coating materials is 15% and the concentration of dispersant is 2.5%;while the best light-durable yellow G microcapsules cladded by UF,whose average particle sizes is 3.2 μm,can be attained with the following conditions:with NH4Cl as catalyst instead of organic acid in the acidic condition,acidification reaction time is 4 h,the pH at the reaction end is 1.5,curing temperature is 70 ℃ and curing time is 2 h.