Poly(vinyl alcohol) (PVA) was derivatized by polymer analogous reaction with thienyl acryloyl chloride and processed to submicrometer fibers by electrospinning from aqueous solution. Water solubility of otherwise water-soluble PVA fibers was reduced considerably by UV cross-linking of thienyl acrylate modified PVA fibers in the solid state. Water stability of these crosslinked fibers was proven by water steam test at 95 degrees C.