Analisis Kadar Abu dengan Gravimetri dan Viskositas dengan Mooney Viscometer pada Karet Remah SIR 20 di PT Rubber Hock Lie

Abstract

SIR 20 crumb rubber is one of Indonesia's leading export commodities that requires strict quality control. Two key parameters in determining its quality are ash content and Mooney viscosity, as both affect the physical properties and durability of the rubber during further processing. This study aims to determine the ash content and Mooney viscosity value of SIR 20 crumb rubber produced by PT Rubber Hock Lie and to compare the results with the quality standards set by SNI 1903:2017. The ash content was analyzed using the gravimetric method by incinerating the sample at 550°C for two hours, while Mooney viscosity was measured using a Mooney Viscometer at 100°C for five minutes (ML 1+4). The test results showed that the ash content for production batches 1 to 5 were 0.50%, 0.52%, 0.52%, 0.48%, and 0.42%, respectively, all below the maximum limit of 1% as stipulated in the standard. The Mooney viscosity values obtained were 72, 70, 72, 73, and 70, which fall within the acceptable range of 65 ±10. Therefore, the SIR 20 crumb rubber produced by PT Rubber Hock Lie meets national quality standards and is deemed suitable for use as a raw material in rubber-based industries such as tire manufacturing and other elastomer products.