|
|||||
|
|
Thermoreversible Thickening and Self-assembly Behaviors of pH/Temperature Dually Responsive Microgels with Interpenetrating Polymer Network Structure |
|
| Authors: | LIU Xiao-yun YANG Jun YAN Wei-xia ZHA Liu-sheng |
| Institution: | 1. Research Center for Analysis and Measurement, Donghua University, Shanghai201620, China 2. State Key Laboratory for Modifrcation of Chemieal Fibers and Polymer Materials, Donghua University, Shanghai 201620, China 3. Research Center for Analysis and Measurement, Donghua University, Shanghai201620, China;State Key Laboratory for Modifrcation of Chemieal Fibers and Polymer Materials, Donghua University, Shanghai 201620, China |
| Abstract: | The pH /temperature dually responsive microgels of interpenetrating polymer network( IPN) structure composed of poly( N-isopropylacrylamide)( PNIPAM) network and poly( acrylic acid)( PAA) network( PNIPAM /PAA IPN microgels) were synthesized by seed emulsion polymerization. The results obtained by dynamic laser light scattering( DLLS) show that the microgels have good pH /temperature dual sensitivities. The temperature sensitive component and the pH sensitive component inside the microgels have little interference with each other. The rheological properties of the concentrated PNIPAM /PAA IPN microgel dispersions as a function of temperature at pH 4. 0 or 7. 0 were investigated by viscometer,and the results displayed that only at pH 7. 0 the dispersions presented thermoreversible thickening behavior. Then the PNIPAM /PAA fibers were prepared by self-assembly of the PNIPAM /PAA IPN microgels in the ice-crystal templates formed by unidirectional liquid nitrogen freezing method. Field emission scanning electron microscopy( FESEM) images indicate that the PNIPAM /PAA fibers are rounded,randomly orientated and interweaved. |
| Keywords: | interpenetrating polymer network (IPN) structure pH and temperature sensitivity thermo-thickening self-assembly |
| 本文献已被 CNKI 维普 万方数据 等数据库收录！ | |