Effect of ratio of 7S and 11S globulin on the properties of the mixture for molded soybean protein materials

Biodegradable materials of soybean protein have been considered as the potential substitution for petroleum-based plastics. It is an effective way to alleviate the shortage of resources and the environmental pollution, and ensure the sustainable development of resources and environment. The objective of this work was to characterize the material performance of soybean protein components. Two major soybean protein fractions, 7S globulin (7S-G) and 11S globulin (11S-G) were separated from defatted soybean flour, and their purities were examined by sodium dodecyl sulfate-polyacrylamide gel eletrophoresis (SDS-PAGE). This thesis mainly solved such a problem: being processed by plasticizers, how to produce the degradable material by the mixture of 7S-G and 11S-G mixed in a proper proportion and modified by succinylation, water caprolactam and glycerol. The effect of 7S-G and 11S-G on the mechanical, water resistant and light-admitting properties of the material, and the content of -S-S- bond were determined. Microstructures of the mixed materials were characterized using scanning electron microscopy (SEM). The relationship between microstructure and properties was illustrated.