Conventional plastics based on petroleum have brought about problems in production and disposal system. The slock of petroleum is limited. Most of plastics were used once before being littered and posing risks to aquatic and marine life through entanglement, ingestion, and suffocation. Therefore, the aim of this research was to develop plastic thin sheet using dammar, an abundant natural resin produced in Indonesia forests and could be biodegraded naturally. The dammar used here were stone dammar, flesh dammar, and cat eye dammar. The research was done in three steps: dammar extraction, thin sheet preparation, and thin sheet characterization. In the first step, dammar was suspended in ethyl acetate at 20% (w/v) subsequently filtrated using filter paper. The thin sheet was prepared by pouring the dammar filtrate onto the aluminium foil. The casting solution was dried in a closed drying system under circulated air
and room temperature to recover the ethyl acetate. After the sheet had been dry. the aluminium foil was detached. Finally, the sheets were characterized as follows: 1) thickness, 2) estimated density. 3) solubility in water, oil, and detergent, 4) hardness, and 5) biodegradability. The result showed that all of dammar-based sheets were insoluble in water. Their thickness depended on the filtrate volume and it could be made as 0.10-0.26 mm thick sheet. Sheet made of cat eye dammar was cloudy white, rigid, and fragile, with the density around 0.6 g cm-3. On the other hand, sheets made of stone dammar and flesh dammar were flexible, smooth, and glossy, with the density around 0.4 g cm-3. Sheet made of stone dammar had bright yellow color, while sheet of flesh dammar was pale brownish yellow. The hardness of stone dammar- and flesh dammar based sheets were 11.69 and 8.16 HV. respectively. Those data indicated that dammar-based sheets were softer than commercial starch-based sheet, which was 45.77 HV. Dammar- based thin sheet could be biodegraded using natural consortium microbe, proved by weight loss and Scanning Electron Microscope Analysis. |