Europhys. Lett.
Volume 72, Number 5, December 2005
Page(s) 760 - 766
Section Condensed matter: structural, mechanical and thermal properties
Published online 03 November 2005
Europhys. Lett., 72 (5), pp. 760-766 (2005)
DOI: 10.1209/epl/i2005-10302-1

Scattering from polymer networks under elongational strain

C. Svaneborg1, G. S. Grest2 and R. Everaers1

1  MPI für Physik komplexer Systeme - Nöthnitzerstr. 38, 01187 Dresden, Germany
2  Sandia National Laboratories - Albuquerque, NM 87185, USA

received 24 May 2005; accepted in final form 30 September 2005
published online 3 November 2005

Molecular-dynamics simulations are used to sample the single-chain form factor of labelled sub-chains in model polymer networks under elongational strain. We observe very similar results for randomly cross-linked and for randomly end-linked networks with the same average strand length and see no indication of lozenge-like scattering patterns reported for some experimental systems. Our data analysis shows that a recent variant of the tube model quantitatively describes scattering in the Guinier regime as well as the macroscopic elastic properties. The observed failure of the theory outside the Guinier regime is shown to be due to non-Gaussian pair-distance distributions.

61.41.+e - Polymers, elastomers, and plastics.
83.85.Hf - X-ray and neutron scattering.
83.10.Rs - Computer simulation of molecular and particle dynamics.

© EDP Sciences 2005