Molecular Weight of Liquid Natural Rubber (LNR) Product from the Chemical Depolymerization Process of High Molecular Weight Narutal Rubber Latex

Abstract

The molecular weight of natural rubber varies greatly, from only a few hundred thousand to more than one million. Liquid natural rubber (LNR) products generally use natural rubber in the form of latex with a relatively low molecular weight, which ranges from a molecular weight of 600,000 g / mol. This study aims to determine the molecular weight of LNR products made from the chemical depolymerization process of natural rubber latex with a molecular weight of more than one million. The natural rubber used latex with 20% Dry Rubber Content (KKK). The natural rubber depolymerization process used NaNO2 and H2O2 degrading agents with a CoCl2 catalyst at 80 °C. H2O2 levels were kept constant at 1 parts per hundred rubber (phr), and NaNO2 levels vary at 0; 2; 3; and 4 phr. After the reactor temperature reaches 80°C, the CoCl2 catalyst was added, which level varied at 0; 1; 3; and 5 phr. The reaction time was varied, which 7, 8, and 9 hours. The results of LNR product was purified to form a semi-gel, and molecular weight was analyzed using gel permeable chromatography (GPC). The results showed that the lowest molecular weight of the resulting LNR product was 108,335 g / mol from the initial molecular weight of 1,384,638 g / mol.