SYNTHESIS OF COPPER STEARATE AS PRO-OXIDANT ADDITIVE FOR OXO-BIODEGRADABLE HDPE (HIGH DENSITY POLYETHYLENE)

• Main Author: Ghani Izzatullah, Harish
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/35157
• Institution: Institut Teknologi Bandung

n recent years, the use of plastics in various applications is constantly increasing. Plastic derived from polyethylene has good mechanical properties, is not easily react with chemicals, difficult degradable in nature, and relatively inexpensive. The very wide use of plastics causes serious environmental problems due to the waste of polyethylene plastic is difficult to be degraded by microorganisms that exist in nature. The use of oxo-biodegradable polymers containing pro-oxidant compounds can be a solution to reduce the accumulation of plastic waste in the environment. In this research, a copper stearate was used as an oxidant additive for preparing oxo-biodegradable (HDPEOx) based on row material of HDPE in various concentrations of pro-oxidant additive (0, 0.05, 0.10, 0.20, and 2.00 % w/w). Films of HDPEOx were conducted by thermal treatment at a temperature of 50, 70, 100 °C and UV irradiation for 1, 5, 10 days. Copper stearate was characterized by using FTIR (Fourier Transform Infra Red) for analysis of the functional group, melting block for determination of the melting point, and Thermogravimetry Analysis (TGA) for thermal analysis. The infra-red spectra shows the shift of the absorption peak of carbonyl group (C = O) from wave number of 1703.50 cm-1 for stearic acid to become 1587.29 cm-1 for copper stearate. The melting point of copper stearate obtained by melting block analysis was in the range of 105 – 108 °C. Films of pure HDPE, HDPEOx with 0.2 % (w/w) additive, HDPEOx with 0.2 % (w/w) additive and followed by thermal treatment at temperature of 70°C, and HDPEOx with 0.2 % (w/w) additive followed by UV irradiation for 10 days have a Young's modulus values of 96.779 MPa, 106.271 MPa, 152.629 MPa, and 138.380 Mpa, respectively. HDPEOx with 0.2 % (w/w) additive and followed by thermal treatment at a temperature of 70 °C or UV irradiation for 10 days, showed no change in the absorption peaks of FTIR spectrum and also no reduction in the mass of polymers during biodegradation test of 30 days, but there’s physical changes in the color of the films to become yellowish. However, HDPEOx with pro-oxidant additive concentration of 2 % (w/w) and followed by thermal treatment for 10 days at a temperature of 25, 50, and 70 °C showed a change in the absorption peaks of FTIR spectra at wave numbers around 1600 – 1800 cm-1, which indicates the formation of new functional groups that is carbonyl groups (C = O), and the values of Young's modulus of these polymers increase with the increase temperature of thermal treatment.