Gamma Radiation Induced Graft Copolymerization Research Articles

Separation of 64+67Cu(II) from irradiated natural zinc target by sodium alginate-polyacrylic acid/nanohalloysite composite

A sodium alginate-polyacrylic acid/nanohalloysite (Alg-PAA/NHA) composite was used to develop a fast and effective method for separating 64+67Cu(II) from a neutron-irradiated natural zinc target. Gamma radiation-induced graft copolymerization was used to prepare the Alg-PAA/NHA composite. Under ideal conditions, the grafting efficiency (GE%) of acrylic acid (AA) on the alginate/nanohalloysite (Alg/NHA) surface reached 99%. To validate the structural morphology and the mechanical properties of the synthesized composite, various analyses including FT-IR, SEM, TGA, and DTA were used. It is worth noting that the Alg-PAA/NHA composite demonstrated selective adsorption of Cu(II) ions over Zn(II) ions at pH 3 with an adsorption efficiency of approximately 86%. Using an acidic solution of 0.1 M HCl, the ionic exchange separation of 64+67Cu(II) from the irradiated Zn(II) target on an the Alg-PAA/NHA composite packed column effectively eluted 64+67Cu(II). For further purification, the eluted 64+67Cu(II) was loaded onto another cationic exchange column packed with Dowex 50 W X8. The radionuclidic, radiochemical, and chemical quality control tests confirmed that the obtained 64+67Cu(II) solution was highly pure and can be safely applied in cancer theranostics Applications.

Gamma Radiation-Induced Graft Copolymerization of Styrene Onto Polyethyleneterephthalate Films: Application in Fuel Cell Technology as a Proton Exchange Membrane

Polyethyleneterephthalate (PET) based proton exchange membrane for using in fuel cells was successfully prepared by gamma radiation-induced graft copolymerization of styrene monomer onto PET film and the consequent selective sulfonation of the grafting chain in the film state using chlorosulfonic acid (ClSO3H). The effects of grafting conditions (e.g., monomer concentration, irradiation dose) on the degree of grafting and sulfonation condition (e.g., optimum concentration of ClSO3H) on the degree of sulfonation were studied. The degree of grafting, the degree of sulfonation and the physico-chemical properties (such as, water uptake, mechanical strength, thermal durability, hydrolytic stability, oxidative stability) of the gamma radiation-induced grafted membrane were found to be better when compared to those of the UV-radiation grafted membrane. The membrane shows higher ion exchange capacity (0.9 mmol g−1) and higher proton conductivity (0.075 S cm−1), similar to those of Nafion membrane.

Effects of Solvent on Gamma Radiation–Induced Graft Copolymerization of Acrylamide onto Poly (3-hydroxybutyrate)

In the present article the gamma radiation–induced graft copolymerization of acrylamide (AAm) onto poly (3-hydroxybutyrate) (PHB) has been carried out by the simultaneous irradiation method. The effect of different solvents on the graft reaction was investigated. The P(HB-g-AAm) thus synthesized were characterized by Fourier transform-infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron micrography (SEM), swelling behavior, and nuclear magnetic resonance (NMR). These results are consistent with successful grafting of acrylamide onto PHB. The addition of chloroform to the grafting medium was the most effective method to increase the graft degree.

Effect of Solvents on Gamma Radiation–Induced Graft Copolymerization of Vinyl Acetate onto Poly(3-hydroxybutyrate)

The effect of different solvents on the radiation-induced graft copolymerization of vinyl acetate onto poly(3-hydroxybutyrate) was studied. Structures of copolymers were determined with the techniques of thermogravimetric analysis and differential scanning calorimetry. From the thermal analysis results, it was found that the more favorable solvent to be used in the graft reaction is hexane. However, a much higher grafting degree can be achieved in bulk. The thermodynamic parameter obtained varied, showing that the enthalpy of melting and crystallization temperature of graft copolymers decreased with increasing grafting degree, which implies changes in the crystallization behavior and decrease in the material cristallinity. Further hydrolysis of the higher grafting degree graft copolymer was also studied.

Gamma radiation induced graft copolymerization of vinylimidazole-acrylic acid onto polypropylene films

Comonomers of vinylimidazole (VI) and acrylic acid (AA) have been grafted onto Polypropylene (PP) films using γ-radiation. The effect of the comonomer composition on the percent graft was investigated. The reactivity ratio of the prepared copolymers was determined by conventional methods. IR spectroscopy, surface morphology, mechanical properties, dyeability, as well as thermal stability of the grafted samples were also studied.

Gamma radiation induced graft copolymerization of acrylamide onto EPDM blended with PE

AbstractGamma radiation induced grafting of acrylamide (AAm) onto vulcanized strips of EPDM and EPDM/PE blends has been carried out. The effects of different parameters on the graft yield have been investigated. These parameters include: radiation dose, monomer concentration, diluent composition and types of inhibitors. It has been found that water is the most appropriate solvent. The preswelling of crosslinked rubber samples in cyclohexane prior to grafting enhances the grafting and the addition of methanol to water as binary diluent in the ratio (1 : 1) decreases the graft yield. The presence of Mohr's salt and copper sulfate in the reaction mixture in the molar ratio (2.1 : 0.5) markedly increases the graft yield. Evidence of grafting have been conducted using thermal analysis as well as swelling measurements in water. Also, it has been found that the mechanical properties of the blends decrease at graft yield 13%. Copyright © 2002 John Wiley & Sons, Ltd.

Gamma radiation-induced graft copolymerization of styrene onto poly(ethyleneterephthalate) films

Gamma radiation-induced graft copolymerization of styrene onto poly(eth- ylene terephthalate) (PET) films was studied using simultaneous irradiation technique. The effects of grafting conditions on the degree of grafting were investigated. The grafting conditions include monomer concentration, irradiation dose, dose rate, and the type of solvent. Moreover, the effect of the addition of crosslinking agents (i.e., divinyl- benzene (DVB) and triallyl cyanurate (TAC)) having various concentrations were also investigated. The degree of grafting was found to be greatly dependent on the grafting conditions. Of the three diluents employed, methylene chloride was found to drastically enhance the degree of grafting. The order of dependence of the initial rate of grafting on the monomer concentration was found to be 2.2. The grafted PET films were identified by FTIR spectroscopy and characterized by X-ray diffraction (XRD). © 2000 John Wiley &

Gamma radiation induced graft copolymerization of acrylamide onto poly(vinyl chloride) films

Grafting of acrylamide (AAm) onto poly(vinyl chloride) (PVC) films using gamma radiation has been carried out. The effects of different parameters on the graft yield have been investigated. These parameters include radiation dose, monomer concentration, solvent composition, types of inhibitors and acidity of the medium. In addition, the effects of the multifunctional monomers N,N′-methylene allyl amide (MAAm) and 2,4,6-triallyloxy-1,3,5 triazine (TARA) on the graft yield have been investigated. It has been found that methanol/water mixture in the ratio (1:1) is the proper diluent mixture for enhancing the graft copolymerization process. The presence of sulphuric acid in the reaction medium adversely affects the graft yield more than acetic acid. The presence of MAAm in the reaction medium markedly increases the graft yield, while TARA has practically no effect on the grafting process. Grafted films have been characterized and evidence of grafting has been obtained using thermal and spectroscopic analysis together with swelling measurements in water. © 1998 SCI.

Gamma radiation induced graft copolymerization of acrylamide onto poly(vinyl chloride) films

Grafting of acrylamide (AAm) onto poly(vinyl chloride) (PVC) films using gamma radiation has been carried out. The effects of different parameters on the graft yield have been investigated. These parameters include radiation dose, monomer concentration, solvent composition, types of inhibitors and acidity of the medium. In addition, the effects of the multifunctional monomers N,N′-methylene allyl amide (MAAm) and 2,4,6-triallyloxy-1,3,5 triazine (TARA) on the graft yield have been investigated. It has been found that methanol/water mixture in the ratio (1:1) is the proper diluent mixture for enhancing the graft copolymerization process. The presence of sulphuric acid in the reaction medium adversely affects the graft yield more than acetic acid. The presence of MAAm in the reaction medium markedly increases the graft yield, while TARA has practically no effect on the grafting process. Grafted films have been characterized and evidence of grafting has been obtained using thermal and spectroscopic analysis together with swelling measurements in water. © 1998 SCI.

Gamma Radiation-induced Graft Copolymerization of - Phenylmaleimide onto Polypropylene Films

Polypropylene (PP) films were grafted with N-phenylmaleimide using γ-radiation. The effect of both monomer concentration and dose rate on the degree of grafting was measured. Characterization of the grafted PP films included IR spectroscopy, X-ray spectroscopy, electrical conductivity, mechanical properties and thermal stability has been studied. © of SCI.

Effect of solvents on gamma radiation induced graft copolymerization of methyl methacrylate onto polypropylene

Methyl methacrylate was grafted onto polypropylene films using gamma radiation. Effects of different parameters, such as radiation dose, inhibitor concentration, monomer concentration, and type of solvents on the graft yield were investigated. It was established that the graft yield depends on the proper choice of solvent mixtures, and its maximum value can be obtained by using decalin/methanol mixture in the ratio 2 : 3 wt %. Thermal characteristics using differential scanning calorimetry shows that grafting has practically no effect on the crystallinity of PP. © 1997 John Wiley & Sons, Inc.

Gamma radiation induced graft copolymerization of acrylate monomers onto isotactic polypropylene

In an attempt to prepare synthetic memberanes for use in desalination of water and as speciality polymeric materials modification of isotactic polypropylene (IPP) by graft copolymerization has been studied. Grafting of acrylate monomers such as acrylonitrile (AN), acrylamide (AAm) and acrylic acid (AAc) onto IPP has been effected by gamma rays from a 2100 ci Co 60 source in air. The preirradiated IPP on heating in the presence of vinyl monomers affords grafting. Different solvents were found to influence grafting. The relative ability of different solvents towards grafting of AN onto IPP was found to follow the order: ▪ Whereas for grafting of AAm and AAc the order observed is: ▪ The percentage of grafting was determined as a function of various reaction parameters. Effect of alcohols of varying chain length upon percentage of grafting of AN onto IPP was studied. Alcohols were found to vary in their ability to influence grafting and the following reactivity order was observed: n – pentanol > n–butanol >tert– >n–propanol >ethanol > isopropanol. A plausible mechanism for graft copolymerization of acrylate monomers onto preirradiatedIPP has been proposed to explain the solvent effects on percentage of grafting. The graft copolymers have been characterized by IR spectroscopic and thermogravimetric methods. Evaluation of grafted polymers as membranes for the desalination water is in progress.

Gamma radiation induced graft copolymerization of vinyl monomers onto poly(vinyl alcohol)

AbstractIn an attempt to modify water‐soluble synthetic polymers, graft Copolymerization of methylmethacrylate (MMA) and ethyl acrylate (EA) onto poly(vinyl alcohol), PVA, has been studied by using gamma irradiation from a Co60 source as initiator. The graft copolymerization was carried out in an aqueous medium by the mutual method in air. The effect of total dose and concentration of vinyl monomers on percentage of grafting has been determined. Water plays a significant role in the enhancement of graft copolymerization and the optimum amount of water to afford maximum grafting has been evaluated. The effect of CH3OH on aqueous grafting of MMA and EA by radiation method has been studied. The graft copolymer has been characterized by IR spectroscopic and thermogravimetric methods.

Radiation‐induced graft copolymerization of methacrylic acid onto polypropylene fibers. I. Effect of synthesis conditions

AbstractThe gamma radiation‐induced graft copolymerization of methacrylic acid onto polypropylene fibers was investigated by simultaneous—irradiation technique. The effect of various synthesis conditions on the graft content was studied. At a constant dose, the percent grafting was found to be higher at low dose rate. For all the dose rates, a linear increase in the grafting was observed up to 0.25 Mrad, beyond which the grafting levelled off. Percent grafting also increased continuously with increasing monomer concentration up to 4.0 mol/L, but a linear increase in grafting was observed only up to 2.0 mol/L. The initial rate of grafting increased with the increase in dose rate and monomer concentration. The dependence of rate of grafting on dose rate and monomer concentration was found to be 0.70 and 1.71, respectively. The effect of liquor ratio upon grafting was also studied.