Development of shape memory polyurethane fiber with complete shape recoverability

Abstract

To illustrate the shape memory properties of shape memory polyurethane (SMPU) fiber and the difference of thermal/mechanical properties between SMPU fiber and other various man-made fibers, series of shape memory polyurethane having various hard segment content were synthesized with the pre-polymerization method and spun with the wet spinning process. Differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and mechanical testing were conducted to study the particular thermal/mechanical properties of shape memory polyurethane fiber in comparison with other man-made fibers such as nylon6, polyester, Lycra and XLA. In addition, in the preparation of shape memory polyurethane fiber, the effect of thermal setting temperature was systematically investigated by mechanical properties testing, DMA and cyclic tensile testing, suggesting that the thermal setting temperature has a huge influence on the mechanical properties and shape memory property due to the elimination of internal stress. Thermal setting with a higher temperature will give rise to a lower tensile modulus and tenacity and a higher elongation ratio at break. Through employing the optimal thermal setting treatment, the complete heating responsive recovery in SMPU fiber can be achieved because of the counteracting effect of the irreversible strain and thermal shrinkage.

Polyurethane: A Shape Memory Polymer (SMP)

“…Various methods such as wet spun, melt spun, dry spun, and electrospun are used for the production of SMPU fiber [50][51][52][53].…”

Shape memory polyurethane foams

“…Thermally actuated SMPs have found broad applications in actuators, smart textiles and coatings, sporting goods [10,11] and in biomedical devices [12]. Recently, triple shape effect and two way shape memory behavior which are largely based on thermal triggering have also been suggested.…”

Smart medical stocking using memory polymer for chronic venous disorders

“…By proper choice of different components (type and molecular weight of switching segment; hard segment content) involved in the formation of the SMP, the T g can be easily adjusted to a particular targeted range [38,39]. Herein, we developed shapememory polyurethane (SMPU) filament with low T g (~30ºC).…”