Self-assembly of Hollow PNIPAM Microgels to Form Discontinuously Hollow Fibers

作     者：Xiao-yun Liu Jian-mao Yang 查刘生 Zi-jun Jiang 

作者机构：Research Center for Analysis and MeasurementDonghua University State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsDonghua University 

出 版 物：《Chinese Journal of Polymer Science》 (高分子科学（英文版）)

年 卷 期：2014年第32卷第11期

页      面：1544-1549页

核心收录：

学科分类：07[理学] 070304[理学-物理化学(含∶化学物理)] 0817[工学-化学工程与技术] 070305[理学-高分子化学与物理] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 

基　　金：supported by the National Natural Science Foundation of China(Nos.51073033 and 51373030) the Fundamental Research Funds for the Central Universities(No.2232014D3-43) 

主　　题：Discontinuously hollow microfiber Ice-segregation-induced self-assembly Thermo-responsiveness N-isopropylacrylamide Microgel. 

摘      要：A new kind of hollow hydrogel microfiber with discontinuous hollow structure was prepared by an ice-segregation-induced self-assembly process. Monodisperse thermo-responsive hollow poly（N-isopropylacrylamide）（PNIPAM） microgels were first synthesized by seed precipitation polymerization using colloidal Si O2 nanoparticles as seeds, followed by removing the silica cores of the formed Si O2/PNIPAM core/shell composite microgels with hydrofluoric acid. Then, the discontinuously hollow hydrogel microfibers were produced by unidirectional freezing of 1 wt% hollow PNIPAM microgel aqueous dispersion in liquid nitrogen bath, followed by freeze-drying to remove the formed ice crystals. Many orderly arrayed dents were observed on the surfaces of the hydrogel microfibers by field-emission scanning electron microscopy, indicating that they are constructed by closely packed monodisperse hollow PNIPAM microgels. The effect of freezing method and the hollow microgel concentration in the aqueous dispersion on the morphological structure of the hollow hydrogel microfibers was investigated.