Shape memory polyurethane‐based electrospun yarns for thermo‐responsive actuation

Abstract

Electrospun nanofibrous yarns of shape memory polyurethane (SMPU)-based nanofibers were successfully prepared. The electrospun yarns were analyzed to assess the dependence of mechanical and shape memory properties on the yarn twist angle. The yarn with a 60 twist angle has high compactness and density, leading to increased tensile strength, elastic modulus, and strain energy. In addition, this yarn shows a significant improvement in the shape memory recovery stress compared with the non-twisted SMPU nanofibers. Moreover, thermal stimuli allowed for the 60 twisted yarn to lift a load that is 103 times heavier than itself. This yarn had a shape recovery stress of 0.61 MPa and generated a 7.95 mJ recovery energy. The results suggest the electrospun yarns could be used as actuators and sensing devices in the medical and biological fields.

State-of-the-art review of advanced electrospun nanofiber yarn-based textiles for biomedical applications

“…Moreover, the chaotically oriented fiber morphology was observed in the as-prepared NYs. In addition, some existing studies employed a high-speed rotating cylinder to collect aligned nanofiber mats and, subsequently, twist the nanofiber mats into short NYs [ 77 , 78 ]. As mentioned above, various modified electrospinning methods have been designed and implemented to manufacture discontinuous electrospun NYs, but it is not very realistic to further apply them into large-scale textile formation due to the limited yarn lengths.…”

Polyaniline Electrospun Composite Nanofibers Reinforced with Carbon Nanotubes

“…Subsequently, researchers have systematically studied different aspects of electrospinning of PANI [4]. While a single-component PANI conductive fi ber with high conductivity and small diameter can be prepared by electrospinning, this method requires special equipment and the prepared fi ber is also quite brittle, limiting the application of this method [5,6].…”

A novel approach for developing smart cotton fabric with dynamic breathability and easy care features

“…An alternative smart method by using shape memory polymers (SMPs) was suggested to obtain novel shape memory effect upon body temperature, home laundry, steaming, and hot wind tumble drying processes which enables environmentally adoptable crease recovery and retention behaviours [17][18][19][20][21], dimensional stability, pattern keeping and bagging recovery [22][23][24][25]. Among the reported SMPs, thermally responsive shape memory polyurethane (SMPU) has paved the way for developing smart garments which have adaptability to dynamic environmental and body physiological changes in the form of films [26][27][28], fiber/yarn to produce fabrics [29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44], fabric coating/ finishing applications [45][46][47][48][49][50][51][52]. Despite obtained smart thermal comfort features based on dynamic permeability [52], SMPU has not achieved much commercial adoption in textile processing because of the disadvantages such as the necessity of excessive polymer concentration for sufficient shape memory effect leading to poor fabric hand [53], insufficient response time, and high activation temperature.…”