The Effect of Citric Acid on the Mechanical and Physical Properties of Bioplastics With Various Bases

The effects of citric acid on the mechanical and physical properties of bioplastics with gelatin, agar, and cornstarch bases were explored. Bioplastics of these three bases were formed with different ratios of citric acid additive, and were stretched using a force gauge to obtain their tensile strength. Results showed that the tensile strength of the gelatin, agar, and cornstarch bioplastics decreased as the ratio of citric acid increased, with the strongest effect on gelatin and the weakest on cornstarch. On the other hand, citric acid seemed to improve the flexibility in all bioplastics tested. Collectively, the test results show that citric acid is inadequate at improving the tensile strength of bioplastics, but shows potential that citric acid combined with other additives can help to develop sustainable, eco-friendly plastic alternatives.