Rubber network in elastomer nanocomposites

EUROPEAN POLYMER JOURNAL

European Polymer Journal 43 (2007) 4143–4150

www.elsevier.com/locate/europolj

Macromolecular Nanotechnology

Rubber network in elastomer nanocomposites M.A. Lo´pez-Manchado *, J.L. Valentı´n, J. Carretero, F. Barroso, M. Arroyo Institute of Polymer Science and Technology, CSIC, Juan de la Cierva, 3, 28006 Madrid, Spain

Abstract The influence of inorganic nanoparticles on crosslinking mechanism of elastomers has been evaluated by applying the tube model on equilibrium statistical mechanics. The results have shown that a highly ordered structure with a huge amount of entanglements, wherein the polymer is nanoscopically confined, is formed by the addition of nanoparticles. These physical links exhibit freedom of movement under stretching, but in a lower volume because of confinement. That is, network molecular parameters such as lateral tube dimensions or average molecular mass of the chains decreased in presence of nanoparticles.  2007 Elsevier Ltd. All rights reserved. Keywords: Nanocomposites; Rubber networks; Crosslinks; Inorganic nanoparticles; Natural rubber

1. Introduction In recent years, hybrid organic–inorganic nanocomposites, consisting of a polymeric matrix and a layered silicate has inspired scientists in a range of potential applications. Due to their nanometer phase dimensions, polymer nanocomposites (PNCs) exhibit unique properties even by the addition of just a low weight percentage (