以1-乙烯基咪唑(1-VIm)和甲基丙烯酸甲酯(MMA)为共聚单体,通过溶液聚合反应合成出4种不同比例的无规共聚物.通过锐孔-凝固浴法,将所得共聚物的四氢呋喃溶液滴入到Cu Cl2水溶液中形成Cu2+-P(VIm/MMA)微胶囊.该微胶囊壁材上的组成部分与离子、分子反应,通过壁材的溶解、分解、解聚而使壁材崩溃或者通过溶胀而改变囊壁的渗透性.通过傅里叶红外光谱、元素分析仪、光学显微镜和扫描电子显微镜对4种不同单体比例的共聚物进行了表征,结果表明当PVM-30浓度为20 g/L时制备的微胶囊成球效果最好,其粒径大小约为1 mm,壁厚为350μm.通过核磁共振氢谱(1H-NMR)分析了PVM-30的结构,利用凝胶渗透色谱(GPC)测定了共聚物的分子量,PVM-30平均分子量在16.0×103左右.利用傅里叶红外光谱和热重分析仪对微胶囊的成分进行了研究,结果表明微胶囊壁材是由PVM与Cu2+配位得到的配位聚合物组成.探索了微胶囊在水溶液中对NO3-、SO42-和CO32-3种离子的响应特性,发现只有浸泡在CO32-离子溶液中的微胶囊的壁材出现了裂痕,最终生成了更稳定的蓝色配位离子溶液,实现了对微胶囊的化学触发.
The random copolymers of different compositions PVM-5, PVM-10, PVM-30 and PVM-44 (where the number indicating the mass percentage of l-Vim monomer) were synthesized by solution eopolymerization of 1-Vim and MMA. The Cu2+ -P(VIm/MMA)-shelled microcapsule was prepared by piercing-bath methode, which is a very simple process, just droping P (VIm/MMA)/THF solution into CuCl2 aqueous solution. The disintegration of shells is caused by dissolution, decomposion, depolymerization when they react with some ions or molecules, or based on permeability change of shell aroused by swelling. The four polymers with different 1- VIm/MMA ratios were studied through FTIR,EA, OM and SEM. The results showed the polymerization effect of PVM-30 was better than that of PVM-5, PVM-10 and PVM-44. The best PVM-30 microcapsules were prepared using solutions with concentration of 20 g/L, and the microcapsule particle size is about 1 mm, and shell thickness is 350 txm. To make sence,the structure of PVM-30 was analysed by 1H-NMR,and the average molecular weight was about 16000 which was measured by GPC. FTIR and TG results demonstrate that the composition of mierocapsules shell is PVM-Cu. The influence of NO3 - , SO42- and CO32- on the shell of microcapsules was studied. The obtained results indicate that microcapsules were cracked by soaking in CO32- solutions,and a more stable blue ligand-ions solution was generated at last, indicating the chemical trigger of microcapsules.