γ辐照对PE的正电子湮灭特性影响  

STUDY OF THE SIZE AND NUMERICAL CONCENTRATION OF FREE VOLUME OF PE IRRADIATED BY γ RAYS

作　　者：贾少晋[1] 张志成[1] 范扬眉[2] 张宪峰[2] 韩荣典[2] 

机构地区：[1]中国科学技术大学应用化学系 [2]中国科学技术大学近代物理系,安徽合肥230026

出　　处：《高分子材料科学与工程》2003年第2期164-167,共4页Polymer Materials Science & Engineering

摘　　要：实验中对纯 L LDPE,LDPE和 HDPE经受了不同剂量辐照的 L LDPE,LDPE和 HDPE样品进行了正电子湮灭寿命谱的测定。当辐射剂量低于 2 5 k Gy时 ,o- Ps的强度 ( I3)和寿命 ( τ3)也随辐射剂量的增大而变小 ,当辐射剂量高于 2 5 k Gy时 ,o- Ps的强度 ( I3)和寿命 ( τ3)基本不变 ,对照 L LDPE,L DPE和HDPE的 o- Ps的强度 ( I3)和寿命 ( τ3) ,可知道自由体积与材料的力学性能有一定的关联。The size and numerical concentration of fr ee volume of PE irradiated and unirradiated were estimated by means of Positron annihilation lifetime measurement, in which annihilations of positron and positr onium were assessed. The observed ortho-positronium(o-Ps) lifetimes(τ 3) and formation probability(I 3) decreased with increase radiation dose be low 25 kGy, and τ 3 and I 3 was nearly constant from 25 kGy to 200 kGy. This fact implies that the mechanical properties of HDPE are related with f ree volume in some degree. These experimental results show that the mechanical properties of HDPE can be explained in terms of free volume size.

关 键 词：Γ辐照 PE 正电子湮灭 特性 影响 自由体积 聚乙烯 

分 类 号：O632.12[理学—高分子化学] O631.34[理学—化学]