Temperature Dependence of Free Volume in Cross-linked Polyurethane Studied by Positrons
HE Chun-Qing1, DAI Yi-Qun1, WANG Bo1, WANG Shao-Jie1, WANG Gui-You2, HU Chun-Pu2
1Department of Physics, Wuhan University, Wuhan 430072 China
2Institute of Material Science and Engineering, East China University of Science and Technology, Shanghai 200237
Temperature Dependence of Free Volume in Cross-linked Polyurethane Studied by Positrons
HE Chun-Qing1;DAI Yi-Qun1;WANG Bo1;WANG Shao-Jie1;WANG Gui-You2;HU Chun-Pu2
1Department of Physics, Wuhan University, Wuhan 430072 China
2Institute of Material Science and Engineering, East China University of Science and Technology, Shanghai 200237
Abstract： Positron annihilation lifetime spectroscopy has been used to study the free volume properties of the cross-linked polyurethane network as a function of temperature in the range from 15K to 300K. The glass transition of polyurethane was observed and the thermal expansion coefficient of the free volume was calculated. Analysis of the ortho-positronium (o-Ps) lifetime distribution shows that the distribution of the free volume in polyurethane is slightly broadened with the increasing temperature in the glassy state, and then significantly broadened with the increasing temperature above the glass transition.
HE Chun-Qing;DAI Yi-Qun;WANG Bo;WANG Shao-Jie;WANG Gui-You;HU Chun-Pu
. Temperature Dependence of Free Volume in Cross-linked Polyurethane Studied by Positrons
[J]. 中国物理快报, 2001, 18(1): 123-125.
HE Chun-Qing, DAI Yi-Qun, WANG Bo, WANG Shao-Jie, WANG Gui-You, HU Chun-Pu
. Temperature Dependence of Free Volume in Cross-linked Polyurethane Studied by Positrons
. Chin. Phys. Lett., 2001, 18(1): 123-125.
2001, Vol. 18 
