The effect of field natural rubber latex pretreatment with cationic exchange resin on latex dipped film properties

Abstract

The current practice of concentrated natural rubber latex production includes the reduction of magnesium ion (Mg2+) with the addition of diammonium phosphate (DAP) before being transferred to undergo concentration by a centrifugation process. But in this process, the chemical reaction between Mg2+ and DAP produces a sludge waste. In this research, cationic exchange resins are used to prevent the formation of sludge waste in the concentrated latex by prior removal of the Mg2+ ions from the field natural rubber latex instead of using chemical precipitation with DAP. Moreover, the extractable protein in the natural latex is absorbed by the cationic exchange resins, which results in low protein levels in the concentrated latex. This method, therefore, allows the manufacture of latex-based articles possessing reduced skin irritability specifically for those who are allergic to latex proteins. Thin films of the resulting latex concentrate on the former were characterised by a film property analysis. The physical properties of latex thin films are found to meet the requirements of ASTM D-3578-01a for natural rubber examination gloves.