Physical ageing of poly(chlorotrifluoroethylene): A positron annihilation study

被引：18

作者：

Ramachandra, P ^{[1
]}

Ramani, R ^{[1
]}

Ramgopal, G ^{[1
]}

Ranganathaiah, C ^{[1
]}

机构：

[1] Univ Mysore, Dept Studies Phys, Mysore 570006, Karnataka, India

来源：

EUROPEAN POLYMER JOURNAL | 1997年 / 33卷 / 10-12期

关键词：

D O I：

10.1016/S0014-3057(97)00034-7

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

Isothermal annealing of poly(chlorotrifluoroethylene) (PCTFE) was carried out at a temperature of 70 degrees C (slightly above T-g) using the positron annihilation lifetime (PAL) technique. Both the o-Ps lifetime and intensity shows systematic variation with ageing time, and its intensity can be represented by two additive decay exponentials. The free volume which is estimated using the Nakanishi et al. equation developed from Tao's model, exhibits Doolittle type free volume relaxation. Physical ageing seems to yield close packing of polymer chains without crystallization. The relaxation time, and the nonexponentiality parameter, were estimated using a Kolrausch-Williams-Watt (KWW) function. (C) 1997 Elsevier Science Ltd.

引用

页码：1707 / 1711

页数：5