A Best-Evidence Review of Bio-based Plasticizer and the Effects on the Mechanical Properties of PLA

Abstract

Polylactic Acid (PLA) plastics are currently used as food packaging material, textiles, and engineering plastics. However, PLA has its weaknesses, such as high brittleness and low toughness, limiting its application. Therefore, the epoxidized vegetable oil is used as a bio-based plasticizer to enhance the mechanical properties of PLA. Recently, many studies in developing bio-based plasticizers were recognized among researchers to replace petroleum-based plasticizers such as phthalate compound, which is known toxic and cause harmful effects on human health and the environment. This review aims to give a clear insight into the impact of bio-based plasticizers blended with PLA. The blends significantly influence the mechanical properties such as tensile strength (MPa) elongation at break (%) and the impact energy (kJ/m2). The bio-based plasticizers discussed in the study include Karanja Oil, Rubber Seed Oil, Palm Oil, and a mixture of Palm Oil with Rubber Seed Oil. Bio-based plasticizers are made from renewable and biodegradable resources, reducing the dependency on petroleum-based plasticizers, resulting in fewer greenhouse gas emissions. Notably, bio-based plasticizers can also expedite plastic biodegradability. This review concludes a bio-based plasticizer blended with PLA improves the elongation at break and impact energy up to 16 % and 35 %, respectively. In contrast, it is also lowering about 15 % of tensile strength. This trade-off advantageously benefits the flexibility and durability of PLA.