Graft copolymerization of N‐vinyl‐2‐pyrrolidone onto sodium carboxymethylcellulose with azobisisobutyronitrile as the initiator

Abstract

Graft copolymers of sodium carboxymethylcellulose with N-vinyl-2-pyrrolidone were prepared in aqueous solutions with azobisisobutyronitrile as the initiator. The graft copolymers [sodium carboxymethylcellulose-g-poly(N-vinyl-2-pyrrolidone)] were characterized with Fourier transform infrared spectroscopy, elemental analysis, nuclear magnetic resonance spectroscopy, differential scanning calorimetry, and scanning electron microscopy. The grafting parameters, including the graft yield of the graft copolymer and the grafting efficiency of the reaction, were evaluated comparatively. The effects of reaction variables such as the time, temperature, and monomer and initiator concentrations on these parameters were studied. The graft yield and grafting efficiency increased and then decreased with increasing concentrations of N-vinyl-2-pyrrolidone and azobisisobutyronitrile and increasing polymerization temperatures. The optimum temperature and polymerization time were 708C and 4.30 h, respectively. Further changes in the properties of grafted sodium carboxymethylcellulose, such as the intrinsic viscosity, were determined. The overall activation energy for the grafting was also calculated to be 10.5 kcal/mol. 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 936-943, 2007

Production of bioethanol by immobilized Saccharomyces Cerevisiae onto modified sodium alginate gel

“…Similar graft copolymerization of N-vinyl-2-pyrrolidone has been reported by other researchers. 31,32 Yigitoglu et al 31 studied grafting of N-vinyl-2-pyrrolidone onto carboxymethyl cellulose with azobisisobutyronitrile as initiator, and the grafting yield increased steadily withincreasing monomer concentration.…”

Graft copolymers of hydroxyethyl cellulose by a ‘grafting to’ method:15N labelling as a powerful characterisation tool in ‘click’ polymer chemistry

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The preparation of graft copolymers of cellulose and cellulose derivatives using ATRP under homogeneous reaction conditions

“…Moreover, the graftcopolymers were found to have thermo-responsive behavior defined by an LCST of 65 °C, however, the graft density and length did not influence the LCST. Above the LCST, the micelles aggregated, resulting in an increase in R h to 180 nm and 120 nm for P(PEGMA) 27 -g-EC 0.2 and P(PEGMA) 185 -g-EC 0.02 respectively and solution turbidity, and these phenomena were shown to be reversible.…”