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Graft copolymerization of methyl methacrylate (MMA) on cellulose or oxycellulose gave a gross polymer product from which the free poly(methyl methacrylate) (PMMA) was easily separated by extraction with benzene. From the residue called the apparent graft copolymer, the unbound or free cellulose/ oxycellulose portion was separated from the cellulose/oxycellu-lose-PMMA graft copolymer portion by extracting the former with 4% aqueous NaOH following a xanthation process. The xanthation method allowed easy determination of efficiency of grafting with respect to cellulose/oxycellulose and degree of true grafting giving moles or moles of PMMA grafted per gram or per mole of cellulose/oxycellulose.

Graft copolymerization of methyl methacrylate (MMA), acrylonitrile (AN), and acrylamide (AA) on cellulose of low degrees of oxidation (effected through periodate treatment) was studied under photoactivation with visible light in limited aqueous systems. The degree of oxidation of the cellulose sample given in terms of copper number was between 0.25 (for the native cellulose) and 46. Increasing degree of oxidation initially produced higher overall % conversion or rate of polymerization. Overall grafting effects, i.e., % grafting and grafting efficiency, were also generally higher in oxycellulose than in unmodified cellulose. Effects of variations of time of polymerization, initiator content, and monomer content on overall grafting were also studied, and related data for the three monomer systems have been presented and compared. Percent grafting as high as 300-500% and grafting efficiency of the order of 80-95% were easily obtained.

Graft copolymerizations of methyl methacrylate (MMA) on cellulose and oxycellulose were studied mostly under photo-activation with visible light using oxalic acid/KMnO4 redox initiator in a limited aqueous system. Polymerization in the dark (40-60°C) produced little graft copolymer, while that in the light at 32° C produced significant or efficient grafting at reasonable rates. Cellulose, modified to degrees of oxidation corresponding to copper number 20-35, produced optimum grafting. Percent grating and grafting efficiency under different sets of conditions were studied and compared, and the mechanism of polymerization and graft copolymer formation discussed. Generation of grafting sites (radical centers) on cellulose/ oxycellulose was consequential only in the presence of light. Generally higher percent grafting and grafting efficiency in oxycellulose systems (as against cellulose systems) appear to be due to more easy and effective generation of radical sites on oxycellulose through oxidation of the aldehydic sites present in them in higher concentrations.

Photograft copolymerization of methyl methacrylate on reduced wool (reduction done by treatment with thioglycollic acid, TGA) was studied at nearly 30°C using a Ce4+ -oxalic acid redox initiator system in a limited aqueous system (2.7 mL water for 0.15 g wool). Reduction of wool for 16 h with 15% TGA solution produced optimum grafting effects. Percent grafting and grafting efficiency under different sets of conditions were studied and compared, and the mechanism of grafting discussed. Generation of grafting sites (radical centers) on reduced wool was more effective in the presence of light than in the dark. Percent grafting of 250-350% and grafting efficiency of 65-80% over a conversion range of 60-90% in 3-5 h were easily obtained.

Disposed battery is a huge source of graphite in our environment. This graphite can be recycled by carrying out electrolysis at fixed voltage and the obtained product can be easily converted into graphene by the generation of graphene oxide (GO) as an intermediate using Hummer’s method. GO is converted into chemically reduced graphite oxide (CRGO) by sodium carbonate treatment and the material obtained is used as a filler in a drug (Ketorolac Tromethamine) loaded Hydroxypropyl methylcellulose (MC) matrix. The KT loaded CRGO\MC nanocomposite films is used to develop transdermal film for drug delivery where CRGO acts as a carrier. The recycled graphite (RGF), GO and CRGO materials has been characterized by Fourier Transform Infrared (FTIR) spectroscopy, X-ray Diffraction (XRD), Ultra-violet (UV) spectroscopy, Transmission Electron Microscopy (TEM), Thermo-Gravimetric Analysis (TGA) and Dynamic Light Scattering (DLS). KT loaded CRGO\MC nanocomposite films are characterized by TGA, XRD and moisture absorption properties analysis. The experimental result reveals the formation of successful exfoliated and stable KT loaded CRGO\MC transdermal film. XRD study reveals the crystalline nature of nanocomposite films. In vitrodrug release studies showed that CRGO\MC based films can be used for controlled transdermal drug delivery applications.

A simple and green chemistry approach for the preparation of reduced graphene oxide nanosheets was successfully demonstrated through the reduction of graphene oxide (GO) to obtain greenly-reduced graphene oxide (GRGO) using various green reagents. Without using toxic and harmful chemicals, this method is environmentally-friendly and suitable for the large-scale production of graphene. The prepared GO and GRGO were characterized by UV–Visible, X-ray diffraction, and Fourier transform infra-red spectroscopic analysis which showed a clear indication of the removal of oxygen-containing groups from the GO and the formation of GRGO. The morphology of the GRGO samples was characterized by transmission electron microscopy. Dynamic light scattering was used to measure the size of the GRGO particles along with zeta potential measurements. Electrical conductivity measurement was used to check the extent of reduction of GO to GRGO samples. The electrochemical properties of these carbonaceous materials were determined by cyclic voltammetry. The methods employed can lead to the preparation of GRGO can be effectively used in sensors and various electronic device fabrications.