Study On Regeneration Of Bombyx Mori Waste Silk

With the growth of people’s wearing demand, silk industry in China has been developing rapidly and the deep processing and utilization of by-products in silk industry are increasingly being valued by people. Waste silk has been used in cosmetics, medicines,medical supplies and other fields, because of its non-toxic, non-allergenic and good biocompatibility. In recent years, polypyrrole(p Py) due to its good biocompatibility, has potential application prospect in the biomedical field. This paper is based on the reuse of waste silk as a starting point and firstly study the effect of acid, alkali, oxidant dosage on such waste silk. Secondly,by comparing the processed waste silk in the experiment, the degummed silk and the waste silk both from the silk spinning factory, we can also discuss the optimal spinning parameters of the waste silk during spinning process. Thirdly, the regenerated silk fibroin fibers(SF) as the supportors are prepared by polymerization with p Py to investigate the influence of various factors on the electrical conductivity of regenerated silk fibroin fibers after polymerization.By changing the processing time, p H value, dosage of oxidant and other influencing factors and using variance analysis method, the paper mainly the effect of p H, processing time and dosage of oxidant on the tensile properties of silk fibroin fibers. The results indicate that the effect of single factor and interaction between two factors both exist during spinning process.In this paper, we prepare three silk fibroin solutions in acid/salt solution system. The processed waste silk can spinning after dissolving(silk:salt=18:6 in weight), while the degummed silk and the waste silk both from the silk spinning factory need to be prepared with silk:salt=24:4 in weight and then stand 24 hours before spinning. After drawing, the mechanical properties of regenerated silk fibroin fibers prepared from above two kinds of silk from silk spinning factory have been greatly improved. The breaking stress andbreaking strain of the two are 117.5±8.9 MPa,78.1±6.7 MPa and 49.5±7.5 %,42.0±3.8 %,respectively.In the preparation of SF/p Py composite conductive fiber, the treatment time, Fe Cl3 concentration, reaction temperature and so on have a great influence on the electrical conductivity. In the study, we immerse the regenerated silk fibroin fibers in 0.6 mol/L Fe Cl3 solution for 10 min. After drying, the fibers are used to react with pyrrole in 5 ℃ for12 h with the principle of chemical oxidation. The conductivity of the fibers can reach to0.089 S·cm-1.Through the study of this paper, we can realize the utilization of waste silk by not only reprocessing to regenerated silk fibers but also giving the fibers special function such as electrical conductivity in order to achieve the goal of high-value-added recycling.