The Properties of Materials from Raw Epoxidised Natural Rubber

Abstract

The raw rubber epoxidised natural rubber (ENR) differs in its chemical structure from the technically specified rubber (TSR) or Standard Malaysian Rubber (SMR) as a result of chemical modification via epoxidation to enhance its properties. This epoxidation value determines the extent of modification in NR is quantitatively determined using the 1H-NMR spectrometry. Besides block rubber, ENR is also available in the form of concentrated latex. The concentrated ENR latex prepared via an ultrafiltration membrane showed an increase in both TSC and DRC. SEM images also showed a softer and more deformable latex particle after the ultrafiltration process. Further understanding of the ENR latex behaviour can be obtained using particle size, particle morphology, zeta potential and rheology. Apart from being concentrated, the ENR latex also acts as the starting raw material in the preparation of liquid epoxidised natural rubber (LENR). In an effort to facilitate an effective chain scission reaction, this chapter delineates the properties of LENR for optimum production conditions. It is noted that the molecular weight and gel content are dependent on the severity of reaction conditions. The thermal property and hydrophilicity of LENR improved due to the degradation. Thus, the polar functional groups on the LENR backbone play an important role in the characteristics and properties of LENR. The shelf life of LENR shows no substantial changes with storage time.