Fabrication of gallic acid containing poly(vinyl alcohol)/chitosan electrospun nanofibers with antioxidant and drug delivery properties.

Chitosan-based nanofibers with excellent properties are attractive materials for specific industrial applications of contemporary interest. This work aims to fabricate functional nanofibers based on poly(vinyl alcohol)/chitosan (CS) with an antioxidant and model drug molecule, gallic acid (GA), by electrospinning, followed by cross-linking through glutaraldehyde (PVA-CS-GAs). PVA-CS-GAs were electrospun at two different concentrations by the adjustment of the CS feeding ratio.

Preparation of a sustainable bio-copolymer based on Luffa cylindrica cellulose and poly(ɛ-caprolactone) for bioplastic applications.

In this research, a bio-based graft copolymer (LCC-g-PCL) based on the cellulose of Luffa cylindrica (LCC) main chain possessing poly(ɛ-caprolactone) (PCL) pendant groups is synthesized through a grafting from approach via ring-opening polymerization (ROP). For this purpose, LCC, extracted from luffa sponges by combined method, is utilized for ROP of ɛ-caprolactone (ɛ-CL) as a macro-initiator in the presence of stannous octoate as a catalyst. Fourier transform infrared (FT-IR), proton and carbon nuclear magnetic resonance (H NMR and C NMR) spectroscopies are utilized to structurally indicate the success of ROP, while the achieved graft copolymer is analyzed in detail by comparing with LCC and neat PCL in terms of wettability, thermal and degradation behaviors by conducting water contact angle (WCA) measurements, thermogravimetric and differential scanning calorimetry analyses (TGA and DSC) and in vitro both hydrolytic and enzymatic biodegradation tests, respectively.

Synthesis of block copolymers by combination of atom transfer radical polymerization and visible light-induced free radical promoted cationic polymerization.

A new synthetic approach for the preparation of block copolymers by mechanistic transformation from atom transfer radical polymerization (ATRP) to visible light-induced free radical promoted cationic polymerization is described. A series of halide end-functionalized polystyrenes with different molecular weights synthesized by ATRP were utilized as macro-coinitiators in dimanganese decacarbonyl [Mn(2) (CO)(10) ] mediated free radical promoted cationic photopolymerization of cyclohexene oxide or isobutyl vinyl ether. Precursor polymers and corresponding block copolymers were characterized by spectral, chromatographic, and thermal analyses.