DEVELOPMENT OF SHAPE MEMORY POLYURETHANE NANOWEB

The objective of this study was to prepare electrospun shape memory PU nanoweb and to characterize physical, thermo-mechanical and comfort properties. By optimizing the conditions for preparation and thermo-sensitive property of PU nanoweb, a comfortable and thermally intelligent membrane was obtained. Effects of electrospinning conditions, such as concentration of polymer solution, electric potential and distance from spinning tip to collector, on the characteristics of electrospun nanoweb were investigated and the optional conditions were determined. Shape memory polyurethane polymers were dissolved in a mixture of tetrahydrofuran (THF) and N,N-dimethylformamide (DMF) in the same volume ratio. It was shown that the solution concentration of 4-7 wt % resulted in the most uniform fibres. The optimum electrospinning conditions were determined as 9kV/1.0ml/hr, 10kV/1.5m1/hr, 14kV/2.0ml/hr and 16kV/2.0ml/hr of flow rate at the concentrations of 4, 5, 6, and 7wt%, respectively. In the investigation of the mechanical property of the electrospun shape memory polyurethane nanowebs, it was found to have a shape recovery of more than 90%. The electrospun web had a high transition temperature compared to the film. And the average pore size of the stretched electrospun web increased by twofold compared to the original web.