ABSTRACT
Hence, the objective of the present study is to propose a simple phenomenological model to capture the Mullins effect observed in swollen rubbers under cyclic loading conditions. Other inelastic responses such as hysteresis and permanent set are not considered. The pseudo-elastic model of Ogden & Roxburgh (1999) is modified and extended in order to account for the swelling level. The dependence of Mullins effect on swelling is probed through mechanical testing of swollen rubbers. Two types of filled rubber are considered: Nitrile Butadiene Rubber (NBR) and Polychloroprene Rubber (CR). The experimental
1 INTRODUCTION
Motivated by the increasing research interest on the renewable energy for cleaner environment and better energy efficiency, palm biodiesel which is derived from renewable sources of palm oil as the feedstock has been introduced as a potential replacement for the conventional fuel. However, the material incompatibility issue causing by the swelling of rubber components when in contact with the palm biodiesel often create problems in the engine system. In addition to the swelling which contributes to the physical degradation in rubber, the rubber components are also subjected to additional mechanical loading. Hence, it is crucial to study the mechanical responses of swollen elastomers for durability analysis of these materials.
