Preparation, Structure And Properties Of Regenerated Silk Fiber With A Ternary Solvent

With calcium chloride/water/ethanol for solvent to dissolve silk, the uniformspinning solution was got, then the regenerated silk fiber was obtained by the wetspinning, the structure and properties of regenerated silk fiber was researched. Thisresearch was mainly divided into three parts:Firstly, the results of the study showed that the change of a ternary solvent andadding citric acid into the spinning coagulation bath have certain effect on the form ofthe regenerated silk fiber. Reducing the water content of the spinning solution, theprimary silk fiber had a more rough surface. Reducing the calcium ions content of thespinning solution, the primary silk fiber had a smooth surface. Adding citric acid intothe coagulation bath with ethanol, the surface of primary silk fiber became more rough.When the citric acid content was0.8%, the rough surface of the primary silk fiber wasthe most obvious.Secondly, the structure and properties of regenerated silk fiber was tested by theinfrared spectrum, X-ray diffraction, TG-DTA and universal material testing machine.Reducing the water content of the spinning solution, the primary silk fiber had anincrease on crystallinity and thermal decomposition temperature, the mechanicalproperties of the stretched fiber was reduced. Reducing the calcium ions content of thespinning solution, the primary silk fiber had a lower crystallinity and thermaldecomposition temperature, the breaking strength of the stretched fiber was increased.When the citric acid content was0.8%in Coagulation bath, the regenerated primarysilk fiber had the Minimum crystallinity and thermal decomposition temperature, themechanical properties of the stretched regenerated fiber was the worst.Thirdly, with the alcoholic solvents of glycerin、polyethylene glycol (peg)200and polyethylene glycol (peg)400on regenerated silk fiber, the structure and properties ofthe regenerated silk fiber had been changed. The results showed that it had a smallercrystallinity with the regenerated primary fiber, a smaller breaking strength and alarger elongation at break with the regenerated stretched fiber. After the processed ofthe regenerated stretched fiber washed by anhydrous alcohol, the fracture strength wasincreased and elongation at break reduced.