摘要
以在50℃水溶液中析出的聚（N-异丙触丙烯酰胺）（PNI-PAM）聚集体作为软模板，使正硅酸乙酯吸附在PNIPAM聚集体表面进行水解缩合，原位生成二氧化硅包裹PNIPAM的核壳结构微球：进一步冷却至室温使PNIPAM溶解在水中除去内核，从而成功合成出SiO2中空微球．实验表明，只有在足够的PNIPAM和正硅酸乙酯含量以及正硅酸乙酯水解时间下，才能形成稳定的SiO2中空微球．用TEM、SEM和FTIR对合成的SiO2中空微球进行了表征，结果表明，微球尺寸为150nm左右，并且由于PNIPAM上酰胺基团和正硅酸乙酯水解出来的硅醇间具有静电相互作用，使得SiO2壳层上依然有PNIPAM残留．
Core-shell structured SiO2/poly（N-isopropylacrylamide） （SiO2/PNIPAM） microspheres were successfully fabricated through hydrolysis and condensation reaction of tertraethyl orthosilicate （TEOS） on the surface of PNIPAM template at 50 ~C. The PNIPAM template can be easily removed by water at room temperature so that SiO2 hollow microspheres were finally obtained. The transmission electron microscope and scanning electron microscope observations indicated that SiO2 hollow microspheres with an average diameter of 150 nm can be formed only if there are enough concentration of PNIPAM and TEOS, and the hy- drolysis time of TEOS. FTIR analysis showed that part of PNIPAM remained on the wall of SiO2 because of the strong interaction between PNIPAM and silica. This work provides a clean and efficient way to prepare hollow microspheres.
