Ps pellets

Prior to prepare electrospun tert-butyl acrylate (tBA)-co-di(ethylene glycol) dimethacrylate (DEGMA) SMP and polystyrene (PS) mixture, the PS pellets (M_w = 35 000, Sigma-Aldrich, Inc.) are dissolved in the toluene (anhydrous, 99.8%; Sigma-Aldrich, Inc.), heated to 50 °C and stirred for 2 hours until PS pellets fully dissolved, in order to prepare the polymer concentration of 25, 30, 35 and 40 wt% PS solutions. The tBA (Sigma-Aldrich, Inc.) and DEGMA (Sigma-Aldrich, Inc.) are mixed at a weight ratio of 85 : 15, followed by adding 1 wt% photoinitiator 2,2-dimethoxy-2-phenyl-acetophenone (Sigma-Aldrich, Inc.) into the solution. Both PS and tBA-co-DEGMA (tD) solutions are mixed (50 : 50 w/w%), and then stirred for another 20 min to obtain homogeneous tD/PS solutions for electrospinning. More details of the synthesis method can be found in our previous publication.^{44 (link)} The chemical structure is shown in Fig. 1a and b.