Study Of Preparation And Biodegradation On Biodegradable Material Of Modified Soy Protein Isolate

Soy protein isolate biodegradable materials as a substitute for conventional oil-based plastics is the new way to solve the environmental pollution, scarcity of resources to ensure sustainable development of resources and environment. Therefore, the research on preparation and properties of materials from SPI are important in terms of both academic field and social applicationsThis paer has prepared degradable material made by compression molding technique from SPI which was modified and plasticized.The influences of various factors (triethylamine content, PEG400 content, reaction temperature and glycerol content, water content and caprolactam content) were researched on variation regularity in relation to material mechanical properties and optical properties. On this basis, the interaction of these factors were observed with orthogonal experiment and were obtained the optimum conditions to prepare degradable materials. At last, soy protein isolate disposable biodegradable tablewares were made successfully.The changes of material structure, composition and characteristics were studied with integrated thermal analysis instrument, X-ray diffraction, UV-visible spectrophotometer et al before and after the formation of protein materials. The research showed: compared to pure protein materials, thermal stability, crystallinity, and disulfide content of the modified protein material have been noticeably improved, but these results were reduced when the protein were handled by complex plascitizers. The study also showed that the mechanical properties and content of material components in the ordered structures have a positive correlation. In addition, the degradable material have good degradation performance which is in line with national standards through the test of degradability.This paper also studied the biodegradable propertie of materials from SPI which was modified by phthalic anlydride in different conditions including the fungal-growth method, the soil-burial method and water-borne soil burial method; the influences of various factors including phthalic anlydride content, reaction temperature, reaction time, triethylamine content and moulding technologies with the fungal-growth method; the property and structure of the SPI materials before and after degrability in fungal-growth condition were studied by the instruments including Elemental analyzer, X-ray diffractometer, SEM, et al. The sresearch showed: materials had good degrability performance in three different conditions; the materials had maxium degradation rate among the three degradation condition (the degradation rates were 65.35%, 56.85%,14.36% in fungal-growth, water-borne soil burial and soil-burial condition after degradation of 25days); the conditons of modification and molding had an significant impact on the degree of material. The study also showed that when the material was decomposed by micro-organisms, the thermal stability and organic carbon content of the material have been significantly reduced. In addition, the uniform structure of its surfaces and sections have become rough; there have been lots of cracks, holes and deep ravines. In addition, the degradation of the material also had a significant impact on the degree of crystallinity changes.