Facile preparation of polyolefin-based amphiphilic graft copolymer fibers by combination of photoinduced graft copolymerization and electrospinning

A novel amphiphilic graft copolymer possessing polypropylene (PP) main chain and poly(oligoethylene glycol methacrylate) (POEGMA) pendant units was synthesized starting from chlorinated polypropylene (PP-Cl), and characterized. PP-Cl produced macroradicals at chlorine bounded carbon atoms by visible light irradiation in the presence of dimanganese decacarbonyl [Mn₂(CO)₁₀] and initiated the free-radical photopolymerization of an acrylate monomer, namely oligoethylene glycol methacrylate (OEGMA). Furthermore, fiber formation ability of PP-g-POEGMA was tested by electrospinning technique. The chemical structure and some features of the corresponding amphiphilic graft copolymer PP-g-POEGMA was characterized by implementing spectral (FT-IR, ¹H-NMR), chromatographic (GPC), morphological (SEM), water wettability (WCA), and thermal (TGA) analyses. It was clear from the SEM results that the average diameter of the obtained microfibers decreased with the incorporation of POEGMA segments onto the PP-Cl main chain. Based on WCA measurements, PP-g-POEGMA was determined as more wettable than PP-Cl due to its hydrophilic POEGMA building blocks. This facile procedure could be utilized to achieve the amphiphilic commercial polymers for potential bioapplications such as drug delivery.