膜孔中有线形接枝链的微囊的分子识别型控制释放特性研究

研制出了一种用于环境刺激感应控制释放的分子识别型微囊。该微囊具有核壳结构多孔膜，并在膜孔中接枝有作为分子识别开关的聚[异丙基丙烯酰胺－共－（苯并－18－冠－6－丙烯酰胺）]（poly(NIPAM0co-BCAm）线形链。采用了界面聚合法核壳结构多孔微囊膜，并采用了等离子体接枝填孔聚合法在膜孔内接枝poly(NIPAM-co-BCAm)线形链。囊内溶质从该微囊中的释放特性明显受环境溶液中Ba^2 离子的存在与否状态所控制。当环境溶液中没有BaCl2分子存在时，由于微囊膜孔内接枝的Poly(NIAM-co-BCAm）聚合物链呈收缩状态而使 开启，所以释放速度快，相反，当环境溶液中有BaCl2分子存在时，微囊膜孔内接枝的poly(NIPAM-co-BCAm）链呈膨胀状态，于是膜孔关闭，从而导致释放速度变得很慢，该具有poly(NIPAM-co-BCAm）接枝开关的微囊的分子识别刺激应释放特性显示出了良好的可逆性和可重复性。

Characterization of Molecular-recognition Controlled-release from Microcapsules Through Pores with Linear-grafted Poly(NIPAM-co-BCAm) Chains

A molecular recognition microcapsule with a core-shell porous membrane and linear-grafted poly(NIPAM-co-BCAm) chains in the pores acting as molecular recognition gates, was developed for environmental stimuli-responsive controlled-release. The preparation was carried out by using interfacial polymerization to prepare the core-shell microcapsules with a porous membrane, and using plasma-graft pore-filling polymerization to graft linear poly(NIPAM-co-BCAm) into the pores in the porous membrane of the microcapsule. The release of solute from the prepared microcapsules is significantly sensitive to the existence of Ba2+ ions in the environmental solution. Without the existence of BaCl2 molecules in the environmental solution, the release is fast because the pores of the poly(NIPAM-co-BCAm)- grafted microcapsule membrane are open due to the shrunken state of the grafted polymer; on the other hand, with the existence of BaCl2 molecules in the surrounding solution, the release rate is very low because the membrane pores are closed by the swelling of the grafted polymer. The poly(NIPAM-co-BCAm)-grafted microcapsules shows a satisfactorily reversible and reproducible molecular recognition stimuli-responsive release.