Positron Annihilation and Chemistry of Groups in Hyperbranched Polymers

摘要：

In this paper, both lifetime and intensity in hyperbranched polymers were measured by using positron annihilation lifetime spectroscopy (PALS) measurements. Ortho-positronium properties upon the degree of branching (DB) have been studied; o-Ps lifetimes maintain a constant while an increase in o-Ps intensities has been detected with DB increasing. Which is inconsistent with authors prediction and indicate that interactions between positronium and the free-volumes are strongly depend on not only the free-volume size properties but also its chemistry environment, due to the variations in the distribution of the different ending groups: -OH and -CH3, caused by DB changes in hyperbranched polymers. The present works demonstrate that in the polar-polymeric application of PALS, effects of the distribution of polar groups should be properly taken into consideration.

关键词： degree of branching hyperbranched positron annihilation free-volume

作者: Wei Gong Ning Qi Bo Wang Yiyong Mai Deyue Yan

作者单位: School of Municipal and Environmental Engineering,Harbin Institute of Technology,Harbin 150090,PR Ch Department of Physics,Wuhan University,430072,China College of Chemistry and Chemical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China

会议类型: 国际会议

会议名称: 第九届国际正电子与正电子素国际会议(9th International Workshop on Positron and Positronium Chemistry)(PPC–9)

会议地点: 武汉

会议语种:英文

页码: 77

在线出版日期: 2008-05-11（万方平台首次上网日期，不代表论文的发表时间）