Modification and Characteristic Analysis of γ-Poly Glutamic Acid as Biodegradable Food Packaging Film
The most existing food packaging plastics are non-biodegradable materials which appear harmful substances precipitation lead to food safety issues, and plastic garbage lead to the environment pollution problems after used. Therefore, biodegradable materials used in the field of food packaging should be gradually expanded in order to reduce or replace the non-biodegradable materials used in the field of food packaging. γ-PGA is a kind of safe, nontoxic biodegradable material, but its strong hydroscopicity can’t meet the requirements of food packaging for the barrier property. The highly absorbent carboxyl of γ-PGA was modified by esterification to make it into hydrophobic material in order to achieve the using requirements of food packaging and the nano-TiO2 was added to make it have certain antibacterial function. The methods of IR, SEM, DSC, etc., were used to analyses characterization of the modified materials. The material after esterification modified has hydrophobic and the structure of esterification modified material with TiO2 added is smooth and uniform. The thermal performance, barrier property and degradability of the material with TiO2 added are better than the other materials.