Synthesis of hybrid polymeric fibers of different functionalized alkoxysilane coupling agents obtained via sol–gel and electrospinning technique: effect on the morphology by addition of PVA

Hybrid functionalized alkoxysilane/PDMS-OH and alkoxysilane/PDMS-OH/PVA polymers were synthesized through acid catalysis sol–gel technique and electrospinning procedure using hydroxyl-terminated poly(dimethylsiloxane) (PDMS-OH), poly(vinyl alcohol) (PVA), and different functionalized alkoxysilane coupling agents: 3-cyanopropyl(triethoxy)silane (CPTEOS), 3-aminopropyl(triethoxy)silane (APTEOS) and trimethoxy(2-phenylethyl)silane (TMPS). Kinetic differences between hydrolyses and condensation of the three functionalized alkoxysilane coupling agents required different curing times to achieve the desired viscosity and enhance electrospinnability. The superficial morphology of the hybrid polymers analyzed by scanning electron microscopy (SEM) showed that the electrospinning solution composed of PDMS-OH and functionalized alkoxysilane coupling agents were deposited as beads. However, when that sol solution was mixed with PVA, a mesh material was obtained. Adding PVA to the functionalized alkoxysilanes sol–gel polymer resulted in improved electrospinnability of functionalized silica-PVA, thereby obtaining a more fiber-like morphology. Besides, sol–gel reactions were confirmed with FTIR, and contact angle test results show that the materials obtained have higher hydrophilicity when they contain PVA.