In this paper, poly （acrylamide-co-acrylic acid） （P（AM-co-AA）） hydrogel was pre- pared in an aqueous solution by using glow-discharge electrolysis plasma （GDEP） induced copoly- merization of acrylamide （AM） ...In this paper, poly （acrylamide-co-acrylic acid） （P（AM-co-AA）） hydrogel was pre- pared in an aqueous solution by using glow-discharge electrolysis plasma （GDEP） induced copoly- merization of acrylamide （AM） and acrylic acid （AA）, in which N,N＇-methylenebisacrylamide （MBA） was used as a crosslinker. A mechanism for the synthesis of P（AM-co-AA） hydrogel was proposed. To optimize the synthesis condition, the following parameters were examined in detail： the discharge voltage, discharge time, the content of the crosslinker, and the mass ratio of AM to AA. The results showed that the optimum pH range for cationic dyes removal was found to be 5.0-10.0. The P（AM-co-AA） hydrogel exhibits a very high adsorption potential and the ex- perimental adsorption capacities for Crystal violet （CV） and Methylene blue （MB） were 2974.3 mg/g and 2303.6 mg/g, respectively. The adsorption process follows a pseudo-second-order kinetic model. In addition, the adsorption mechanism of P（AM-co-AA） hydrogel for cationic dyes was also discussed.展开更多
Various semi-interpenetrating polymer network（semi-IPN） hydrogels composed of pore-forming agent polyethylene glycol（PEG）, acrylic acid（AA） and acrylamide（AM） were prepared by using free radical polymerization...Various semi-interpenetrating polymer network（semi-IPN） hydrogels composed of pore-forming agent polyethylene glycol（PEG）, acrylic acid（AA） and acrylamide（AM） were prepared by using free radical polymerization with a two-step method. The chemical structures of the synthesized hydrogels were characterized by FTIR spectroscopy and the morphologies were studied by scanning electron microscopy（SEM） method. The swelling properties, such as the p Hresponsive behavior, salt sensitivity, oscillatory swelling/de-swelling behaviors in different solutions with various p H values and self-oscillating behaviors in bath p H oscillator were investigated in detail. The results revealed that the prepared hydrogels exhibited high p H sensitivity and excellent salt sensitivity when the p H values of the medium changes from 3.0 and 7.0 and well reversible properties by undergoing a number of swelling/de-swelling recycles. In particular, the hydrogels exhibited self-oscillation behavior in a closed system containing Br O3？-SO32？-Fe（CN）64？-H＋. This study may create a new possibility as biomaterial for new self-walking actuators and other devices.展开更多
The association and properties of multi-block like copolymers(TP)of acrylamide(AM)and acrylic acid(AA)prepared by template copolymerization in aqueous solution were studied.The results showed that the copolymers of th...The association and properties of multi-block like copolymers(TP)of acrylamide(AM)and acrylic acid(AA)prepared by template copolymerization in aqueous solution were studied.The results showed that the copolymers of this type exhibited a significant structure effect compared with that of similar random copolymers(CP)obtained by copoly-merization in the absence of template.Decreasing the value of pH or adding Ca2+ion to the copolymer solution will make phase separation occur.The TEM images demonstrated that the phase separation caused by Ca2+ion was due to the forma-tion of extensively intermolecular cross-linking.With the increase of the pH value of copolymer solution,the changes of the solution viscosity was similar with that of homopoly-acrylic acid,which originally increased and then decreased.But the increase range of template copolymer was higher than that of homopolyacrylic acid.TEM images indicated that at the maximal viscosity the copolymer obtained in the presence of template formed coiled aggregates.展开更多
基金supported by National Natural Science Foundation of China(No.21367023)Natural Science Foundation of Gansu Province,China(No.1208RJZA161)Key Project of Young Teachers’ Scientific Research Promotion of Northwest Normal University of China(Nos.NWNU-LKQN-10-16 and NWNU-LKQN-12-9)
文摘In this paper, poly （acrylamide-co-acrylic acid） （P（AM-co-AA）） hydrogel was pre- pared in an aqueous solution by using glow-discharge electrolysis plasma （GDEP） induced copoly- merization of acrylamide （AM） and acrylic acid （AA）, in which N,N＇-methylenebisacrylamide （MBA） was used as a crosslinker. A mechanism for the synthesis of P（AM-co-AA） hydrogel was proposed. To optimize the synthesis condition, the following parameters were examined in detail： the discharge voltage, discharge time, the content of the crosslinker, and the mass ratio of AM to AA. The results showed that the optimum pH range for cationic dyes removal was found to be 5.0-10.0. The P（AM-co-AA） hydrogel exhibits a very high adsorption potential and the ex- perimental adsorption capacities for Crystal violet （CV） and Methylene blue （MB） were 2974.3 mg/g and 2303.6 mg/g, respectively. The adsorption process follows a pseudo-second-order kinetic model. In addition, the adsorption mechanism of P（AM-co-AA） hydrogel for cationic dyes was also discussed.
基金financially supported by the Basic Project of Science and Research of Colleges and Universities of Gansu Province(No.5001-109)the Natural Science Foundation of Gansu Province(No.1010 RJZA015)
文摘Various semi-interpenetrating polymer network（semi-IPN） hydrogels composed of pore-forming agent polyethylene glycol（PEG）, acrylic acid（AA） and acrylamide（AM） were prepared by using free radical polymerization with a two-step method. The chemical structures of the synthesized hydrogels were characterized by FTIR spectroscopy and the morphologies were studied by scanning electron microscopy（SEM） method. The swelling properties, such as the p Hresponsive behavior, salt sensitivity, oscillatory swelling/de-swelling behaviors in different solutions with various p H values and self-oscillating behaviors in bath p H oscillator were investigated in detail. The results revealed that the prepared hydrogels exhibited high p H sensitivity and excellent salt sensitivity when the p H values of the medium changes from 3.0 and 7.0 and well reversible properties by undergoing a number of swelling/de-swelling recycles. In particular, the hydrogels exhibited self-oscillation behavior in a closed system containing Br O3？-SO32？-Fe（CN）64？-H＋. This study may create a new possibility as biomaterial for new self-walking actuators and other devices.
文摘The association and properties of multi-block like copolymers(TP)of acrylamide(AM)and acrylic acid(AA)prepared by template copolymerization in aqueous solution were studied.The results showed that the copolymers of this type exhibited a significant structure effect compared with that of similar random copolymers(CP)obtained by copoly-merization in the absence of template.Decreasing the value of pH or adding Ca2+ion to the copolymer solution will make phase separation occur.The TEM images demonstrated that the phase separation caused by Ca2+ion was due to the forma-tion of extensively intermolecular cross-linking.With the increase of the pH value of copolymer solution,the changes of the solution viscosity was similar with that of homopoly-acrylic acid,which originally increased and then decreased.But the increase range of template copolymer was higher than that of homopolyacrylic acid.TEM images indicated that at the maximal viscosity the copolymer obtained in the presence of template formed coiled aggregates.
