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.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2003年第2期164-167,共4页
Polymer Materials Science & Engineering
