The Potential of Enzyme in Reducing the Maturation Time and the Use of Ammonia in Concentrated Natural Rubber Latex

Abstract

One of the most important parameters for indicating colloidal stability of concentrated natural rubber latex (CNRL) is the mechanical stability time (MST). The MST of CNRL after centrifugation is always low and slowly increases with storage time due to gradual hydrolysis of phospholipid on the surface of rubber particles into fatty acid soap. In this work, enzymatic approach was investigated to increase the colloidal stability of CNRL by using different grades and amounts of enzymes. The enzymes were tested with 2 grades of CNRL, which are the high-ammonia latex (HA latex) and low-ammonia latex (LA latex). We found that the MST of LA latex treated with 0.004% and 0.04% of Lipex reach the acceptable value (at least 600 sec.) within 14 and 10 days, respectively. In case of HA latex, the MST reached the acceptable value faster than that of LA latex (within 10 and 3 days at amount 0.004% and 0.04% of Lipex, respectively) while, the MST of commercial laurate-treated latex only increased slightly and could not pass the acceptable value after 31 days. In addition, the use of enzyme instead of laurate soap could reduce the use of ammonia in CNRL production.