利用环氧丙醇对介孔二氧化硅SBA-15的表面进行碳羟基修饰,然后以此为引发剂,异辛酸亚锡为催化剂,分别引发己内酯(CI.)及氨基甲酸苄基酯-ε-己内酯(CABCL)单体的开环聚合,成功地制备了杂化材料聚己内酯/SBA15(PCL/SBA-15)和聚4-氨基甲酸苄基酯己内酯/SBA15(PCABCL/SBA-15),酸解去除PCABCI./SBA—15的保护基团甲酸苄酯(Cbz)后得到聚氨基己内酯/sBA15(PACL/SBA-15)。通过X射线衍射仪(XRD)、N2吸附-脱附实验和热重分析(TGA)等手段研究了材料的结构变化、反应时间和空间位阻效应对接枝量的影响等。结果表明:聚合物的修饰未对介孔结构产生影响;PCL的接枝量可以通过聚合反应时间进行控制;对PACL/SBA-15而言,因CABCL中Cbz的位阻效应导致接枝量较小;Zeza电位分析的结果证明聚氨基己内酯的修饰改变了二氧化硅表面的电荷性质。
Hydroxyl modified SBA 15 (SBA-15-OH) was achieved by the reaction with glycidol. Using Sn(()ct)2 as catalyst, the ring opening polymerization of ε-caprolactone and γ- (carbamic acid benzyl ester) ε-caprolactone was initiated by SBA-15-OH, and the hybrids poly(caprolactone)/SBA 15 (PCL/SBA-15) and poly γ-(arbamic acid benzyl ester)-~ caprolactone)/SBA-15 (PCABCL/SBA-15) were obtained. After removal of the protective groups (Cbz) by acid, poly(γ-amino-ε caprolactone)/SBA-15 (PACL/SBA 15) was obtained. The structural change and the content of the grafted polymer were analyzed by XRD, nitrogen adsorption-desorption and TGA. The results showed that the polymer modification did not affect the mesoporous structure of hybrids and the grafted amount of PCL could be controlled by reaction time. For PACL/SBA-15, the steric effect of the Cbz groups in CABCL led to the low grafting content in polymerization. Moreover, the Zeta potential results demonstrated that the surface charge property of silica was regulated by the modification of PACL.