Keywords : post polymer reaction


Grafting of Poly (acrylonitrile) on Cellulose to Synthesize and Characterize Potential Functional Polymers for Development of Metal Ion Sorbents

Suresh Kumar

International Research Journal on Advanced Science Hub, 2020, Volume 2, Issue Special Issue ICAMET 10S, Pages 23-27
DOI: 10.47392/irjash.2020.194

Grafting of Acrylonitrile onto cellulose from different sources, using a variety of chemical initiators under various reaction conditions has been thoroughly investigated and reported. Hydrophobic nature of acrylonitrile hinders the partition of metal ions form aqueous phase thus narrows the applicationspectrum of its graft copolymers inseparation and enrichment processes. However, this drawback can be improved by post functionalization of nitrile (-CN) group to generate hydrophilic/ionic moieties by simple reactions like hydrolysis or substitution. In present study, acrylonitrile (AN) was grafted onto commercial cellulose to produce graft copolymers which can be used as starting materials for development of efficient metal ions sorbents. Grafting was carried out by redox initiation method using Ce+4 ions following the earlier reported scheme at the optimum grafting conditions worked out for grafting of AN onto  cellulose ether, Hydroxyethyl cellulose(HEC). Graft copolymer thus obtained [hereafter called cell-g-poly (AN)] was characterized by Elemental analysis and FTIR. Both, cellulose and HEC belong to same back bone therefore, exhibited similar behaviour towards grafting. Percent grafting (Pg =50) obtained in case of cellulose was in close agreement with (Pg=55.5) that observed in case of HEC. Cell-g-poly (AN) served as useful precursor to develop reactive metal ion sorbing polymer supports as nitrile (-CN) moiety of poly (AN) is amenable to post functionalization and could be conveniently modified to targeted metal ion chelating amido-oxime group [poly (NH2-C=NHOH))] thus  the resultant polymer  could be used as a novel support for metal ion sorption.

A Study in Sorption of Cu+2 , Fe+2 and I2 onto Graft copolymers of Cellulose with N-Vinyl Pyrrolidone and Butyl Acrylate, and Their Functionalized Derivatives

Suresh Kumar

International Research Journal on Advanced Science Hub, 2020, Volume 2, Issue Special Issue ICIES 9S, Pages 44-47
DOI: 10.47392/irjash.2020.157

Cellulose is of special interest due to its abundance in nature and it provides excellent materials for membranes both in native and derivatized forms. Graft copolymers of cellulose when used in separation and enrichment technologies have advantages over the conventional ones, due to chemical resistance, radiation stability and low cost of preparation. Cellulose based graft copolymers and hydrogels offer large hydrophilic area despite being insoluble in water and enrich or separate metal ion by binding, adsorption, chelation and ion exchange processes. Potential of cellulose as sorbent can be improved by radiation and chemical grafting, crosslinking and polymer analogous reactions on some graft copolymers. Grafting of suitable monomers with hydrophobic and hydrophilic/ionic moieties combine high degree of selectivity, permeability and longer stability, and enables complexation with low molecular weight species. Incorporation of functional groups like nitrile, hydrazino, hydroxamic acid and phosphate by derivatization and post polymer reactions enhances metal ion sorption capacity of Cellulosics. In present study an attempt has been made to study the sorption of Fe+2, Cu+2 and I2 on select graft copolymers of cellulose with N-Vinylpyrrolidone (1-Vinyl-2-prrolidone, N-VP) and Butyl Acrylate(BuAc) on to cellulose and some of their functionalized derivatives, on the basis of lowest to highest percent grafting (Pg). An attempt has also been made to investigate selectivity in metal ion sorption and effects of structural aspects of functionalized graft copolymers to find their end-uses as cost effective and eco-friendly polymeric materials for waste water management technologies.