PERTANIKA JOURNAL OF SCIENCE AND TECHNOLOGY

This degradable plastic derived from modified sago starch is designed to reduce the use of synthetic polymers. In this study, we used radiation technology to improve how easily degradable materials can degrade. The gamma-ray doses used were 5 kiloGray (kGy), 10 kGy, and 20 kGy. Energy absorption analysis revealed that exposure to radiation caused a rise in the melting point of degradable plastic. The highest recorded melting point was 527.17°C at a dose of 20 kGy, with a fusion enthalpy of 562.67 J/g. Meanwhile, for plastic without radiation, the melting point was 515.54°C, and the latent heat of melting (∆H fusion) was 694.44 J/g. In this instance, polymer degradation and exothermic peaks have been observed at without and all radiation doses. Thermal stability found that using zero radiation dose resulted in only a little depolymerisation and weight loss (442.06°C-511.37°C; 92.57%). However, using 10 kGy of radiation led to a higher level of depolymerisation compared to other doses, which resulted in weight loss (457.13°C to 516.70°C; 98.04%). In the chemical compound on degradable plastics without radiation dose and all radiation doses, there are C-H; OH; -CH2-CH2 and C=O groups, the plastic material underwent decomposition within the soil. It was characterised as both organic and hydrophilic. The biodegradation rate of irradiated plastics is twice as fast which cuts the degradation time in half when compared to no radiation exposure. Extrapolation analysis shows that all plastics will be fully degraded by nature within 7 years of burial.