Degradasi Fotokimia Karet Alam sebagai Compatibilizer Campuran Aspal

Abstract

The degradation of natural rubber (NR) molecular chains to produce degraded natural rubber (NRd) using photochemical methods has been successfully carried out. The degradation process was carried out using a 30-watt UV lamp, 0.25 mol H2O2, sodium lauryl sulfate (SLS) surfactant, and 20% dry rubber content of NR and carried out for 72 hours at 70oC. From Gel Permeation Chromatography (GPC) data, the molecular weight of NR decreased by 50%, with the polydispersity value decreasing from 35.11 to 7.5, indicating that NR had experienced chain termination. The FT-IR data shows that the termination of the NR molecular chain occurs in the C-C alpha bond to produce a terminal hydroxyl group marked by the appearance of vibration at wave number 3381cm-1. The resulting NRd is then mixed with asphalt with variations of NRd 8; 10; 12; 14; 16% to the mass of asphalt. From the test results of the essential characteristics of asphalt (softening point, penetration, and ductility), the addition of 12% NRd to asphalt is the most optimum mixture with a softening point, penetration, and ductility values of 60,5 oC, 56,75 (0.1 mm), and 105.5 cm respectively, which complies with SNI 8198:2015. The 12% Asphalt-NRd mixture was then added to aggregate to produce a sand sheet, and then its stability was tested using a Marshall tool. From the Marshall test results, the optimum ratio of the Asphalt-KAd mixture to aggregate was 6,35: 93,65, with values of marshall stability is meeting the SNI 06- 2489-1991.