Research Interest 

Yang Jie’s main research interest sits in the understanding of mechanical behaviour of the variety of polymers. Elastomeric Polyurethane (EPU) is an amorphous polymer with excellent tear strength, low wave speeds, strong impact resistance, and a low glass transition temperature. As a result, EPU has become increasingly popular among many applications including coatings, low-speed tyres, automobile carpets, medical equipment, and other industrial applications. A two-domain (hard & soft domains) conformation forms EPU. The hard segments tend to aggregate due to the easily formed hydrogen bond, whilst the soft segments function as the flexible continuous matrix in which hard domains intersperse. This kind of multiblock architecture of EPU can benefit energy dissipation and reduce shock velocity by interconnecting the hard segments.   For instance, understanding the shape-memory behaviours of EPU are concerned. Shape-memory polymers (SMPs) are widely used in biomaterials, sensors, micro-actuators, and textile fibres. They are smart materials that can recover to their original shape when exposed to external stimuli like heat, magnetic fields, electric fields, and so on. Compared to the shape-memory alloys, this kind of polymer can be low cost, lightweight, and have high ductility. EPU can be the representative one among SMPs.  Overall, there are  very few studies about the mechanical properties of EPU under different temperatures. In addition, the current literature of shape-memory behaviours of heat-activated EPU is also insignificant. In summary, the wide range of applications for EPU necessitates a thorough understanding of its mechanical properties and development of accurate computational modelling.