PROCESS FOR COAGULATING AND CONCENTRATING EPOXIDISED NATURAL RUBBER LATEX

摘要

The present invention discloses a process of treating epoxidised latices with ionic salts to reduce the phase separation temperature of the non-ionic detergent used in epoxidation of natural rubber latex and thence effecting coagulation of the latex with acid at a reduced temperature including room temperature. Preferably, the ionic salt is ammonium sulphate at a concentration range of about 0.2 to 1% based on the water phase. The treated latex may then be coagulated by the addition of formic acid at temperatures ranging from 28 to 40 °C. Following treatment with salt, the epoxidised latex may be treated with ammonia and subjected to centrifugation or creaming to obtain epoxidised latex concentrate having dry rubber content (DRC) in excess of 50%.