Soil Burial Studies for Biodegradation of Natural Rubber Latex Films

Abstract

Starch is added into the natural rubber (NR) latex as filler to assist the biodegradation of NR latex which normally takes longer period to biodegrade. The soil burial test for 1, 2, 3 and 4 weeks at room temperature was carried out on the unfilled-, 10% starch-, and alkali gelatinized starch-filled NR latex films. The progress of biodegradation was investigated through weight loss measurement, tensile test, scanning electron microscopy (SEM), and fourier transform infrared spectrometry (FTIR) analysis. Results indicated that the NR latex films showed an obvious increment of weight loss percentages after buried for 4 weeks compared to the control films. The 10% alkali gelatinized starch performed the tensile strength retained up to two weeks before decreased at longer soil burial periods. Referring to morphological analysis, the voids on the NR latex films became larger with the addition of starch. From FTIR analysis, the addition alkali gelatinized starch was increased the hydroxyl and carbonyl groups in NR latex films after 4 weeks of soil burial test.