Fig. 4.
a Schematic illustration showing fabrication of a porous tube by combining melt electrospinning with direct writing by using a rotating collector on a translating stage. Due to the characteristic lag effect of the melt electrospinning jet, the effective translation of the jet (Te) which corresponds to the tube height is shorter than the actual programmed translation of the stage (Tp). b Porous tube fabricated by combining melt electrospinning of PCL with direct writing. c SEM image showing smooth uniform fibers interwoven and oriented at 60° to the central axis of the tube