The graft polymerization of acrylic acid(A) and acrylamide(B) was carried out onto bi-oriented polyester BOPET corona film.The influence of monomer concentration,reducer concentration and reaction time on the graft po...The graft polymerization of acrylic acid(A) and acrylamide(B) was carried out onto bi-oriented polyester BOPET corona film.The influence of monomer concentration,reducer concentration and reaction time on the graft polymerization was investigated.The surface tension of the films increased with an increase of monomer concentration,till the concentration of monomer A reached 1.5×10^(-2)g/mL and the concentration of monomer B reached 4.0×10^(-2)g/mL.The surface tension of the films reached a maximum value at 7×10^(-4)M of reducer concentration and subsequently decreased with further increase in reducer concentration.The surface tension of the films increased with the increase of the reaction time apparently within 50min.The grafted corona BOPET films were characterized with IR and XPS.The presence of graft on the film surface was confirmed.The attenuation experiments on grafted corona BOPET films in air at 50℃ and in water were carried out to investigate the persistence of graft polymerization of acrylic acid and arylamide onto BOPET corona films.展开更多
Radiation induced graft polymerization on polymeric matrix followed by functionalization is widely accepted for the preparation of metal adsorbents. In this paper, a pre-irradiation method was used for emulsion graft ...Radiation induced graft polymerization on polymeric matrix followed by functionalization is widely accepted for the preparation of metal adsorbents. In this paper, a pre-irradiation method was used for emulsion graft polymerization of 4-hydroxybutyl acrylate glycidylether (4-HB) onto polyethylene/polypropylene (PE/PP) nonwoven fabric. The degree of grafting (Dg) which can be calculated by weight increment was determined as a function of reaction time, irradiation dose, and monomer concentration. After 30 kGy irradiation, with 4-HB concentration of 5%, surfactant Span 20 of 0.5% at 40°C for 2 h, the trunk polymer was made grafted at a Dg of 135%. 4-HB-grafted PE/PP nonwoven fabric was modified by ethylenediamine (EDA) in isopropyl alcohol (IPA) as a solvent at 60°C. With a Dg of 135%, the amine group density of the adsorbent is 2.8 mmol/g. The adsorption test was carried out by batch experiment in several metal ion solutions, and the removal ratio from the EDA modified adsorbent of the metal ions is in the order of Cu2+ > Pb2+ > Zn2+ > Ni2+ > Li+. Compared with glycidyl methacrylate (GMA) which is a typical functional monomer for graft polymerization, 4-HB-grafted adsorbent exhibited not only better mechanical property but also higher adsorption capacity of Cu2+ and Pb2+.展开更多
Membrane fouling is one of the most important challenges faced in membrane ultrafiltration operations. The copolymers of polysulfone-graft-methyl acrylate were synthesized by homogeneous photo-initiated graft copolyme...Membrane fouling is one of the most important challenges faced in membrane ultrafiltration operations. The copolymers of polysulfone-graft-methyl acrylate were synthesized by homogeneous photo-initiated graft copolymerization. The variables affecting the degree of grafting, such as the time of UV （Ultraviolet-visible） irradiation and the concentrations of the methyl acrylate and photoinitiator, were investigated. The graft copolymer membranes were prepared by the phase inversion method. The chemical and morphological changes were characterized by attenuated total reflection-Fourier transform infrared spectroscopy （ATR/FT-IR）, scanning electron microscopy, and water contact angles measurements. Results revealed that methyl acrylate groups were present on the membranes and the graft degree of methyl acrylate had remarkable effect on the performance of membranes. Pure water contact angle on the membrane surface decreases with the increase of methyl acrylate graft degree, which indicated that the hydrophilicity of graft copolymer membranes was improved. The permeation fluxes of pure water and bovine serum albumin solution were measured to evaluate the antifouling property of graft copolymer membranes, the results of which have shown an enhancement of antifouling property for graft copolymer membranes.展开更多
The copolymers were formed by the graft copolymerization of PVC with acrylic rare earth. The principle and method of the graft copolymerization of PVC and acrylic rare earth were discussed. The graft copolymers were c...The copolymers were formed by the graft copolymerization of PVC with acrylic rare earth. The principle and method of the graft copolymerization of PVC and acrylic rare earth were discussed. The graft copolymers were characterized by FT-IR spectra and scanning electron microscope (SEM).The thermal stability of the graft-copolymers was studied by thermogravimetric analysis (TG). The experiment results show that the thermal resistance and toughness of the graft copolymers are obviously enhanced.展开更多
It is difficult to find a solvent of grafting copolymer of acrylic acid onto polystyrene, thus it is not easy to analyse its structure by ordinary methods. Until now, many scientists considered that grafting reaction ...It is difficult to find a solvent of grafting copolymer of acrylic acid onto polystyrene, thus it is not easy to analyse its structure by ordinary methods. Until now, many scientists considered that grafting reaction occurs on the main chain of polystyrene. In this work, the radiation grafting mechanism is studied with solid NMR and infrared. We have found that the grafting position is on the meso position of phenyl ring of polystyrene when the solvent is methanol and the matrix is polystyrene and a preirradiation method is used. It展开更多
A superabsorbent resin was prepared through free-radical polymerization in aqueous solution,which used konjac glucomannan(KGM),acrylic acid(AA)and acrylamide(AM)as raw materials.Graft polymerization was initiated by p...A superabsorbent resin was prepared through free-radical polymerization in aqueous solution,which used konjac glucomannan(KGM),acrylic acid(AA)and acrylamide(AM)as raw materials.Graft polymerization was initiated by potassium persulfate(K2S2O8),with N,N′-methylene-bis-acrylamide(NMBA)was used as crosslinking agent .The relationships between the water absorption of the resin and the amounts of initiator,crosslinker,AA and AM as well as reaction temperature,reaction time were studied.This superabsorbent polymer was capable of absorbing distilled water up to 720 times and 0.9%NaCl solution 110 times in its saturated state at ambient temperature when the mass ratio of KGM to monomer was 1∶4,the amount of initiator was 0.35%(based on the weight of monomer),the neutralization degree of monomer was 80 %,the reaction temperature was 55～65℃,and the amount of crosslinker was 0.075%(based on the weight of monomer).Experimental results indicated that the introduction of nonionic group would be suitable for improving absorption ability and salt-resistance of the resulting hydrogels.展开更多
文摘The graft polymerization of acrylic acid(A) and acrylamide(B) was carried out onto bi-oriented polyester BOPET corona film.The influence of monomer concentration,reducer concentration and reaction time on the graft polymerization was investigated.The surface tension of the films increased with an increase of monomer concentration,till the concentration of monomer A reached 1.5×10^(-2)g/mL and the concentration of monomer B reached 4.0×10^(-2)g/mL.The surface tension of the films reached a maximum value at 7×10^(-4)M of reducer concentration and subsequently decreased with further increase in reducer concentration.The surface tension of the films increased with the increase of the reaction time apparently within 50min.The grafted corona BOPET films were characterized with IR and XPS.The presence of graft on the film surface was confirmed.The attenuation experiments on grafted corona BOPET films in air at 50℃ and in water were carried out to investigate the persistence of graft polymerization of acrylic acid and arylamide onto BOPET corona films.
文摘Radiation induced graft polymerization on polymeric matrix followed by functionalization is widely accepted for the preparation of metal adsorbents. In this paper, a pre-irradiation method was used for emulsion graft polymerization of 4-hydroxybutyl acrylate glycidylether (4-HB) onto polyethylene/polypropylene (PE/PP) nonwoven fabric. The degree of grafting (Dg) which can be calculated by weight increment was determined as a function of reaction time, irradiation dose, and monomer concentration. After 30 kGy irradiation, with 4-HB concentration of 5%, surfactant Span 20 of 0.5% at 40°C for 2 h, the trunk polymer was made grafted at a Dg of 135%. 4-HB-grafted PE/PP nonwoven fabric was modified by ethylenediamine (EDA) in isopropyl alcohol (IPA) as a solvent at 60°C. With a Dg of 135%, the amine group density of the adsorbent is 2.8 mmol/g. The adsorption test was carried out by batch experiment in several metal ion solutions, and the removal ratio from the EDA modified adsorbent of the metal ions is in the order of Cu2+ > Pb2+ > Zn2+ > Ni2+ > Li+. Compared with glycidyl methacrylate (GMA) which is a typical functional monomer for graft polymerization, 4-HB-grafted adsorbent exhibited not only better mechanical property but also higher adsorption capacity of Cu2+ and Pb2+.
文摘Membrane fouling is one of the most important challenges faced in membrane ultrafiltration operations. The copolymers of polysulfone-graft-methyl acrylate were synthesized by homogeneous photo-initiated graft copolymerization. The variables affecting the degree of grafting, such as the time of UV （Ultraviolet-visible） irradiation and the concentrations of the methyl acrylate and photoinitiator, were investigated. The graft copolymer membranes were prepared by the phase inversion method. The chemical and morphological changes were characterized by attenuated total reflection-Fourier transform infrared spectroscopy （ATR/FT-IR）, scanning electron microscopy, and water contact angles measurements. Results revealed that methyl acrylate groups were present on the membranes and the graft degree of methyl acrylate had remarkable effect on the performance of membranes. Pure water contact angle on the membrane surface decreases with the increase of methyl acrylate graft degree, which indicated that the hydrophilicity of graft copolymer membranes was improved. The permeation fluxes of pure water and bovine serum albumin solution were measured to evaluate the antifouling property of graft copolymer membranes, the results of which have shown an enhancement of antifouling property for graft copolymer membranes.
文摘The copolymers were formed by the graft copolymerization of PVC with acrylic rare earth. The principle and method of the graft copolymerization of PVC and acrylic rare earth were discussed. The graft copolymers were characterized by FT-IR spectra and scanning electron microscope (SEM).The thermal stability of the graft-copolymers was studied by thermogravimetric analysis (TG). The experiment results show that the thermal resistance and toughness of the graft copolymers are obviously enhanced.
文摘It is difficult to find a solvent of grafting copolymer of acrylic acid onto polystyrene, thus it is not easy to analyse its structure by ordinary methods. Until now, many scientists considered that grafting reaction occurs on the main chain of polystyrene. In this work, the radiation grafting mechanism is studied with solid NMR and infrared. We have found that the grafting position is on the meso position of phenyl ring of polystyrene when the solvent is methanol and the matrix is polystyrene and a preirradiation method is used. It
文摘A superabsorbent resin was prepared through free-radical polymerization in aqueous solution,which used konjac glucomannan(KGM),acrylic acid(AA)and acrylamide(AM)as raw materials.Graft polymerization was initiated by potassium persulfate(K2S2O8),with N,N′-methylene-bis-acrylamide(NMBA)was used as crosslinking agent .The relationships between the water absorption of the resin and the amounts of initiator,crosslinker,AA and AM as well as reaction temperature,reaction time were studied.This superabsorbent polymer was capable of absorbing distilled water up to 720 times and 0.9%NaCl solution 110 times in its saturated state at ambient temperature when the mass ratio of KGM to monomer was 1∶4,the amount of initiator was 0.35%(based on the weight of monomer),the neutralization degree of monomer was 80 %,the reaction temperature was 55～65℃,and the amount of crosslinker was 0.075%(based on the weight of monomer).Experimental results indicated that the introduction of nonionic group would be suitable for improving absorption ability and salt-resistance of the resulting hydrogels.
