Mucoadhesive thermo-responsive chitosan-g-poly(N-isopropylacrylamide) polymeric micelles via a one-pot gamma-radiation-assisted pathway.

Thermo-sensitive graft copolymer amphiphiles of chitosan (CS) and poly(N-isopropylacrylamide) (PNiPAAm), CS-g-PNIPAAm, were successfully synthesized by a catalyst-less one-pot gamma (γ)-radiation-assisted free radical polymerization at three different radiation doses: 5, 10 and 20 kGy. The chemical structure of the copolymers was confirmed by FTIR and solid-state (13)C NMR and the grafting extent by (1)H NMR and gravimetric analysis. In general, the higher the dose, the smaller the grafting due to the more significant NiPAAm homopolymerization.

Graft copolymerization of ethyl acrylate onto tamarind kernel powder, and evaluation of its biodegradability.

In the present study, tamarind kernel powder and ethyl acrylate were reacted by free radical polymerization to synthesize a grafted copolymer soluble in water. The grafted copolymer was analyzed by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR); FTIR showed a shift of the vibration of R-CO-OR' from 1258 cm(-1) to 1253 cm(-1). This shift appeared because of the grafting copolymerization.

Use of 4-piperidones in one-pot syntheses of novel, high-molecular-weight linear and virtually 100%-hyperbranched polymers.

4-Piperidone and 4-alkyl piperidones react selectively with aromatic hydrocarbons in a mixture of trifluoromethanesulfonic acid (TFSA) and CH(2)Cl(2) to give linear polymers, while N-(2-phenethyl)piperidone undergoes self-polymerization to yield virtually 100%-hyperbranched polymer.