Intrafibrillar bridging structures in strained isotactic polypropylene

被引：8

作者：

Tsobkallo, K

Tikhomirov, A

Tshmel, A

机构：

[1] Russian Acad Sci, AF Ioffe Physicotech Inst, Fracture Phys Dept, St Petersburg 194021, Russia

[2] St Petersburg State Univ Technol & Design, St Petersburg 191185, Russia

来源：

POLYMER | 2004年 / 45卷 / 05期

关键词：

isotactic polypropylene; tangent modulus; LAM;

D O I：

10.1016/j.polymer.2003.12.054

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

The films made of isotactic polypropylene were strained up to 0.8 of their ultimate strain and subjected to isometric stress relaxation during 5 days. The strain-stress curves were measured at various stages of the sample treatment and the tangent moduli (E-t) of unstrained, as-strained and relaxed films were determined. The changes of values of E-t were put in comparison with the structural evolution of strained samples observed using the infrared and low-frequency Raman spectroscopic techniques. It was concluded that the three-dimensional intercrystallite bridges composed of straight-chain segments of lengths L-c < L < 2L(c) (L-c is the average thickness of crystallites) destruct as a result of chain-breaking process, but due to the chain-straightening events in isometrically relaxing samples, the intercrystallite space transforms to the rigid amorphous phase composed of 'individual' one-dimensional molecular stems. (C) 2003 Elsevier Ltd. All rights reserved.

引用

页码：1689 / 1696

页数：8

共 24 条

[1] IN-SITU OBSERVATION OF THE PLASTIC-DEFORMATION OF POLYPROPYLENE SPHERULITES UNDER UNIAXIAL TENSION AND SIMPLE SHEAR IN THE SCANNING ELECTRON-MICROSCOPE [J].