Evaluation of Potential of Two Natural Proteins as Surface Modifiers to Enhance Reinforcing Action of Silica in Natural Rubber Latex Films

Research at a glance

It is well known that self aggregation of silica is a serious issue in NR latex compounding since silica has to be added as an aqueous dispersion. Maintaining the colloidal stability of latex compounds after blending with silica is also not that easy. In the present study, applicability of two natural polymers, zein and soya protein, in modifying silica particle surfaces and thereby preventing self aggregation of silica particles was evaluated. The modified fillers were characterised by FTIR spectroscopy. The performance of protein modified silica in vulcanised latex films was evaluated using a selected latex compounding formula at two different level of additions; 2.5 and 5.0 pphr. Of the two proteins tested soya protein was found to be better than zein in terms of conferring colloidal stability to aqueous silica dispersions. However, the physical properties of vulcanized latex films containing zein modified silica were found to be better than those of similar films containing soya protien modified silica.