Production of biodegradable plastics from cucurbita moschata (yellow pumpkin) starch and chitosan with castor oil as flasticizer

• Main Author: Fahimah Mohd Rahalim
• Format: Undergraduate Final Project Report
• Published: 2021
• Online Access: http://discol.umk.edu.my/id/eprint/13469/

Conventional plastics used all over the world are petroleum or natural gas polymers, which are difficult to break down naturally in less than 50 years. Depending on the type of traditional plastics, plastic waste can stack in the landfill and cause environmental harm. As a response, many scientists have created bioplastic frombio-based. materials such as seeds, agricultural waste, microorganisms and municipal solid waste. Meanwhile, Cucurbita moschata (yellow pumpkin) starch shows a great potential to be the main raw ingredient source due to it has quite high starch content. Thus, this project is to produce biodegradable plastic from yellow pumpkin, which is the main raw material that can easily be found in Malaysia. Based on the result of this research project, the bioplastic films from Cucurbita moschata starch and chitosan are successfully produced with the smooth surface morphology properties and the colour obtained are from light yellow to orange that is influenced by the yellow pigment from Cucurbita moschata starch. For tensile strength test, S4 with the composition of 25% chitosan and 75% yellow pumpkin starch is the highest tensile strength of 7.872 Mpa, while S5 with the composition of 100% yellow pumpkin starch without the addition of chitosan is the lowest tensile strength of 1.635 Mpa. Meanwhile, the highest elasticity is the S1 with composition of 100% chitosan without the addition of yellow pumpkin starch with the Young modulus value of 4.011 Mpa, while the lowest elasticity is the S5, the bioplastic film with composition of 100% yellow pumpkin starch without the addition of chitosan with the Young modulus value of 9.015 Mpa. For solvent uptake tests, the sample containing a higher proportion of pumpkin starch had a very high solvent uptake due to the hydrophilic character of the starch, while the bioplastic film with the equal ratio of chitosan and Cucurbita moschata starch had the lowest solvent uptake that indicate it has a great resistance to water. Lastly, for the biodegradability test, S5, the bioplastic film with the composition of 100% yellow pumpkin starch is the most degradable with the degradation rate of 70.41% after 10 days, followed by S4, the bioplastic film with the composition of 75% yellow pumpkin starch and 25% chitosan with the degradation rate of 31.01% after 10 days.