Wheat gluten-based renewable and biodegradable polymer materials with enhanced hydrophobicity by using epoxidized soybean oil as a modifier.

Epoxidized soybean oil (ESO) was applied as an additive for wheat gluten (WG) to modify the properties of the renewable and biodegradable natural polymer materials. Optimum intermolecular interactions and crosslinking between ESO chains and the WG matrix were achieved under alkaline conditions. The WGESO materials were heterogeneous on a scale of 20-30 nm, but the homogeneity was improved upon increasing the amount of glycerol as a plasticizer in the materials. The combination of plasticization and crosslinking effects derived from ESO resulted in good retention in mechanical strength for the plasticized WGESO materials as compared to those without 10 wt% of mobile ESO additives. The hydrophobicity of the plasticized WG materials was also enhanced significantly by using the ESO additives.