Conformational Transition of Poly (Acrylic Acid) Detected by Microcantilever Sensing
LI Kai1, LIU Hong2, ZHANG Qing-Chuan1, XUE Chang-Guo1, WU Xiao-Ping1
1CAS Key Laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China, Hefei 2300272Department of Chemical Physics, University of Science and Technology of China, Hefei 230026
Conformational Transition of Poly (Acrylic Acid) Detected by Microcantilever Sensing
LI Kai1;LIU Hong2;ZHANG Qing-Chuan1;XUE Chang-Guo1;WU Xiao-Ping1
1CAS Key Laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China, Hefei 2300272Department of Chemical Physics, University of Science and Technology of China, Hefei 230026
摘要Poly (acrylic acid) (PAA) chains are grafted on one side of a microcantilever by the self-assembled method and the deflections of the microcantilever are detected as a function of medium pH from 3 to 11. It is found that when the pH varies, the microcantilever deflects because of the changing surface stress. By analysing the electrostatic repulsive effect, the surface stress change is related to the conformation transition of PAA from a collapse state to a swelling state. This method offers the interaction information among the polymer chains during the conformational transition and affords an alternative way to study conformational change of polymers.
Abstract：Poly (acrylic acid) (PAA) chains are grafted on one side of a microcantilever by the self-assembled method and the deflections of the microcantilever are detected as a function of medium pH from 3 to 11. It is found that when the pH varies, the microcantilever deflects because of the changing surface stress. By analysing the electrostatic repulsive effect, the surface stress change is related to the conformation transition of PAA from a collapse state to a swelling state. This method offers the interaction information among the polymer chains during the conformational transition and affords an alternative way to study conformational change of polymers.
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2007, Vol. 24 
