Thermally stimulated current measurements on epoxidized natural rubber (ENR50) – organically modified montmorillonite composite

Materials Science Laboratory, Physics Department, University of Malaya, 50603 Kuala Lumpur, Malaysia

Corresponding author: abdrashid_4@hotmail.com

Received: 5 May 2004
Revised: 15 August 2004
Accepted: 7 September 2004
Published online: 23 November 2004

Abstract

Composites consisting of epoxidized natural rubber (ENR) and organically modified montmorillonite (OMON) in the ratio of 70:30 by weight percent have been synthesized. X-ray diffraction (XRD) measurements were made to estimate the basal plane spacing between the layered structures of the montmorillonite (MON) before and after it was organically modified and also for the composite. The increment in basal spacing of 1.758 nm indicated that intercalation of ENR-50 chains occurred in the silicate layers with the ammonium ion being attached to the layers after the modification. TSC measurements indicated that the intercalation resulted in a suppression of the  peak of the ENR around -25 °C which is also referred to as the T_g of the material. Two new and broader peaks around 30 °C and 73 °C appeared in the composite. The suppression of the peak may be interpreted as a result of the increasing rigidity due to the three-dimensional network of physical links formed.