Adwait K. Pradhan

Grafting Vinyl Monomers onto Cellulose. VI. Graft Copolymerization of Methyl Methacrylate onto Cellulose Using Potassium Permanganate as the Initiator

Abstract The graft copolymerization of methyl methacrylate onto cellulose using tetravalent manganese as the initator has been studied. AII increase in initiator concentration up to 1.0 × 10−2 M increases the graft yield. With a further increase, the graft yield decreases. The graft yield also increases with an increase of monomer concentration and temperature. There is an initial increase in graft yield with acid concentration up to 4.5 × 10−2 M after which the graft yield decreases. The effect of addition of solvents, CuSO4 concentration, and redox system on the rate of grafting has been studied and a suitable kinetic scheme has been pictured.

Grafting Vinyl Monomers onto Cellulose. VIII. Graft Copolymerization of Methyl Methacrylate onto Cellulose Using H2-O2-Cysteine Redox System

Abstract The application of the H2O2-cysteine redox system to induce graft copolymerization of methyl methacrylate onto cellulose was investigated under various conditions. The rate of grafting was determined by varying the concentrations of monomer, initiator, cysteine, acid, and temperature. The effect of some solvents was studied and a suitable reaction mechanism has been proposed.

Grafting Vinyl Monomers onto Silk Fibers. XIII. Graft Copolymerization of Methyl Methacrylate onto Silk Using Fe3+−Cysteine Redox System

Abstract The graft copolymerization of methyl methacrylate onto silk fibers initiated by the ferric chloride-eysteine redox system has been investigated in aqueous medium. The rate of grafting was calculated by varying the concentrations of monomer, initiator, acidity of the medium, cysteine, and temperature. The percentage of grafting increases with an increase of Fe3+ concentration up to 2,5 × 10−3 mol/L and thereafter it decreases. The graft yield increases steadily upon increasing the monomer concentration. The graft yield also increases with increasing cysteine concentration up to 0.5 × 10−3 mol/L and then decreases. The effect of the perchloric acid concentration, temperature, solvents, and certain neutral salts on graft yield has also been investigated and a suitable reaction scheme has been proposed.

Grafting Vinyl Monomers onto Cellulose. IX. Graft Copolymerization of Methyl Methacrylate onto Cellulose Using Peroxydiphosphate-Fe(ll) and Mn(ll) Redox Systems

Abstract The application of peroxydiphosphate coupled with bivalent metal ions like Fe(n) and Mn(II) to induce graft copolymerization of methyl methacrylate onto cellulose fibers by varying the concentrations of monomer, initiator, acid, reducing agent, solvents, and temperature has been studied. The rate of grafting increases progressively with increasing monomer and reducing agent concentrations. The rate of grafting also increases with peroxydiphosphate concentration up to 10.0 × 10−3 M and with sulfuric acid concentration up to 9.0 × 10−2 M after which it decreases. The effects of addition of some solvents and temperature on graft yield were also studied. The effect of modified cellulose on the rate of grafting was also studied. Both systems have been investigated under identical conditions. A larger percentage of grafting was observed in the case of Mn(II) than of Fe(II). A suitable kinetic scheme has been developed, and rate equations have been derived.

Photo-induced graft copolymerization: VII—Graft copolymerization of methyl methacrylate onto nylon-6 using peroxydiphosphate as photoinitiator

Abstract Photo-induced graft copolymerization of methyl methacrylate onto nylon-6 was investigated using peroxydiphosphate ion as the photoinitiator. The percentage graft yield increases with increasing both the monomer and initiator concentration. The reaction was carried out at three different temperatures and the overall activation energy was computed. The kinetic data and other evidence indicate that the overall polymerization takes place by a radical mechanism. A suitable kinetic scheme has been suggested.

Grafting Vinyl Monomers onto Nylon 6. VIM. Graft Copolymerization of Methyl Methacrylate onto Nylon 6 Using Peroxydiphosphate-Fe(ll) and Mn(ll) Redox Systems

Abstract The graft copolymerization of methyl methacrylate onto nylon 6 initiated by peroxydiphosphate coupled with bivalent metals like Fe(II) and Mn(II) is studied. The rate of grafting increases progressively with increasing the peroxydiphosphate, monomer, and acid concentrations. The graft yield also increases with increasing the concentrations of Fe(II) and Mn(II) from 5.0 × 10−4 to 60 × 10−4 M. The effect of the addition of some solvents and temperature on graft yield is also studied. Both systems were investigated at identical conditions. A larger percentage of grafting is observed for Mn(n) than for Fe(II). A suitable kinetic scheme is developed and rate equations are derived.