Preparation And Biocompatibility Study Of Epichlorohydrin Cross-linked Soy Protein Isolate/Polyurethane Composite Sponge

The increasing scarcity of oil resources and the environmental pollution caused by the extensive use of petroleum-based non-degradable materials have seriously threatened human being's sustainable development.Therefore,the use of environment-friendly polymers based on natural renewable resources has attracted much attention.Soy protein isolate(SPI)is an abundant resource of renewable natural polymers with the characteristics of low price,simple process of extraction,excellent biocompatibility and biodegradability.However,the wide utilization of soy protein is limited because of its water-sensitivity and brittle property.Waterborne polyurethanes(WPU)are synthetic polymers,while they have the advantages of structure,mechanical properties and biodegradability can be designed as well as environmental friendly properties.Thus the objective of this thesis is to prepare a series of Epichlorohydrin cross-linked Soy Protein Isolate/Polyurethane Composite Sponges by blending and coagulation process.These Epichlorohydrin cross-linked Soy Protein Isolate/Polyurethane Composite Sponges were expected to have potential applications as new biomaterials with good water-resistance,mechanical properties and biodegradability.The main contents and conclusions of this thesis are as follows:A series of WPU/SPI composite films was prepared by blending and coagulation process using water-borne polyurethane and soy protein isolate as the raw materials and NaOH/urea solution as the co-solvent.The structure and physical properties of the final Composite Sponge were investigated by Fourier transform infrared spectra measurement,scanning electron microscopy,Differential Scanning Calorimetry,thermogravimetric analysis and tensile testing.The biocompatibilty,biodegradability and cytocompability of the Composite Sponges were evaluated by in vitro cell culture,in vivo implantation experiments and blood compatibility experiment.The results indicated that,with an increase in the SPI content,the Composite Sponges increased water absorption,increased hydrophobicity,improved thermal stability,and increased elongation.The results from the in vitro cell culture experiments showed that some Composite Sponges exhibited good cytocompability,and soy protein could promote the cell adhesion,growth and proliferation as well as improve the cytocompability of the composites.The results from the in vivo implantation experiments showed that the composites had good tissue compatibility and biodegradability,and the SPI composition could promote the biodegradation of the Composite Sponges.Therefore,the Epichlorohydrin cross-linked Soy Protein Isolate/Polyurethane Composite Sponges fabricated in this work might have potential applications in the field of biomaterials.