Effect of different aeration levels on natural rubber latex upon maturation

Abstract

Mechanical Stability (MS) of Natural Rubber Latex (NRL) is practically important to the latex producer and consumer whenever latex is handled. MS of fresh NRL is very low and fresh NRL cannot be directly used for manufacturing processes. Thus, freshly tapped NRL is kept for maturation and MS naturally develops and achieve steady level around 21 days. Water soluble fatty acid soap is used as an accelerator for the MS development and excess soap is added by NRL manufacturers to cut-down the maturation time. Appearing tiny pin holes on dipped latex films is one the major drawback due to excess soap in NRL. The main aim of this research was to find the alternative method to accelerate the MS development process without adding excess soap. Aeration of NRL was selected as an alternative technique and NRL samples were matured with different levels of air quantity and minimum soap content which is needed only to centrifuge. It was found that Mechanical Stability Time (MST), Volatile Fatty Acid (VFA) Number, Alkalinity, Conductivity and Viscosity changed with the air quantity. At minimum soap level, time duration to obtain standard MST was changed with air quantity. VFA number was slowly increased as air quantity increase, but it was not very significant.