The Study Of Spandex Aging Behavior Based On Structure And Performance Characterization

Polyurethane fiber(spandex) materials are widely used in textile & medical & precision instrument replacing the tradition materials, cause for the superior performance. There are known for the degradation of ageing problems in the long-term using process. Eventually, lead to some security issues. In this paper, a typical polyurethane fiber materials be studied Carried out the UV accelerated damp & hot aging test at different aging time and humidity andthe chlorine water accelerated aging test under different aging time. The Fourier infrared spectroscopy(FT-IR) and X-ray diffraction analysis(XRD) and other material analysis method were used to analy chemical structure changes and micro structural change in the area of the polyurethane fiber after ultraviolet aging and chlorine water aging. The differential scanning thermal analysis(DSC) and thermogravimetric analysis(TG) were used to analy the physical and chemical performance of polyurethane fiber after ultraviolet and chlorine water aging. Use of mechanical characteristic curve and the tensile response curve reflects mechanical performance changes of the polyurethane fiber after ultraviolet aging and chlorine water aging. Used the rule of the time, temperature, humidity and vacuum degree on the properties of spandex ultraviolet aging to predict the remaining service life.(1) In the chlorine water aging process, the chloride ion take the place of N-H and C-H, changed to N-Cl, C-Cl. Make its internal structure of crystallinity increased after the first decreases, and glass transition temperature decreased. The tensile modulus increased first and then, the elongation at break has declined.(2)In ultraviolet aging process, its hard chain segment parts have taken place in nonferrous group formation reaction of ageing, reduced the molecular chain segments. Increased the number of hydrogen bonds, the crystallinity increase after partial first. On the mechanical properties, tensile modulus increase after decreases first, and elongation at break increased, the tensile resilience has declined always. The soft segment and hard segment of polyurethane fiber structure have influenced in different humidity, mainly is the water molecules swelling to plasticizing of soft segment. Made original hydrogen bond rupture and recombination. After further spread to the hard segment, and carbamate hydrolysis reaction, formed a large number of hydroxyl groups. And the modulus and break strength decreased with increasing humidity. Aging temperature mainly affects soft segment structure of polyurethane fiber, with the increase of aging temperature, the ether of soft segment base hydrogen bond increases, the thermal decomposition temperature of the hard segment, and the quality change.The high temperature aging, the hard segment structure change is not big, modulus of change is not big, just the elongation at break increased, response rates decreased obviously.After aging in vacuum environment, the structure is not a significant change, just breaking strength decrease slightly.(3)Based on the identified the accelerated aging test of temperature, humidity, vacuum effects on its performance. From textile, life prediction, efficient use of reasonable measures for the three parties face its reliability analysis. The spinning of synthetic optimization technology. The life prediction model was established, and predicted its life span. Put forward to enhance the reliability of polyurethane fiber in the use of the use of reasonable and efficient measures.This paper’s research reveals the spandex chlorine water and ultraviolet aging mechanism. Effectively predicted the spandex ultraviolet under the service of the remaining service life. This not only provides a theoretical basis for the efficient and safe use of spandex, and help for to develop a synthetic high weatherability of spandex. Solved the security problem focusing on the perspective of intrinsically safe material aging.