Conformation of cyclic and linear polydimethylsiloxane in the melt: a small-angle neutron-scattering study

被引：16

作者：

Gagliardi, S

Arrighi, V

Dagger, A

Semlyen, AJ

机构：

[1] Heriot Watt Univ, Dept Chem, Edinburgh EH14 4AS, Midlothian, Scotland

[2] Univ York, Dept Chem, York YO10 5DD, N Yorkshire, England

来源：

APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING | 2002年 / 74卷 / Suppl 1期

关键词：

D O I：

10.1007/s003390101110

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

In this study we report small-angle neutron-scattering measurements of cyclic and linear polydimethylsiloxane (PDMS) in the melt. It has been suggested that due to the presence of topological constraints, rings in the melt may be more compact than Gaussian chains. We show that the cyclic chains are partially collapsed and do not follow Gaussian statistics: the weight-average radius of gyration R-g,(w) is found to be proportional to M-w(0.53) and M-W(0.40) in the case of linear and cyclic PDMS, respectively. The results are in agreement with recent computer simulations, which predict R-g to be proportional to N-2/5, where N is the degree of polymerisation.

引用

页码：S469 / S471

页数：3

共 25 条

[1]

[Anonymous], 1986, CYCLIC POLYM

[2] Symmetric, isotopic blends of poly(dimethylsiloxane) [J].