To correct the defects of hydrophobic association hydrogels (HA-gels), new physically and chemically cross-linked hybrid hy- drophobic association hydrogels (hybrid HA-gels) were prepared by radical copolymerizati...To correct the defects of hydrophobic association hydrogels (HA-gels), new physically and chemically cross-linked hybrid hy- drophobic association hydrogels (hybrid HA-gels) were prepared by radical copolymerization of acrylamide (AM), octylphe- nol polyoxyethylene (n) acrylate (OPnAC, n stands for the number of ethoxy group, and is 10 and 21) and N,N'-methylene- bisacrylamide (MBA). On the basis of the statistical molecular theory of rubber elastic, the Mooney-Rivlin model and using the tensile true stress (O'true) tested at room temperature, the number of network strands per unit volume (o~) and the num- ber-average molar mass of a network strand (Me) were evaluated for hybrid HA-gels. For the hydrogels, the effect of the con- tent of MBA and OP10AC on their tensile mechanical properties was studied by using o0 and Mc; also, the effect of the com- positions and temperature on their swelling behavior in distilled water was discussed in detail. In addition, hybrid HA-gels in- cluding a small quantity of MBA possessed the capabilities of secondary self-healing and remolding. In contrast with HA-gels prepared by the same compositions besides MBA, hybrid HA-gels showed good mechanical strength and long-term thermal stability in distilled water in the range of 25 to 80℃. Furthemore, hybrid HA-gels also avoided the self-deswelling behavior of HA-gels. The results show that the application fields of HA-gels will be greatly broadened after introducing a chemical cross-linking network.展开更多
文摘To correct the defects of hydrophobic association hydrogels (HA-gels), new physically and chemically cross-linked hybrid hy- drophobic association hydrogels (hybrid HA-gels) were prepared by radical copolymerization of acrylamide (AM), octylphe- nol polyoxyethylene (n) acrylate (OPnAC, n stands for the number of ethoxy group, and is 10 and 21) and N,N'-methylene- bisacrylamide (MBA). On the basis of the statistical molecular theory of rubber elastic, the Mooney-Rivlin model and using the tensile true stress (O'true) tested at room temperature, the number of network strands per unit volume (o~) and the num- ber-average molar mass of a network strand (Me) were evaluated for hybrid HA-gels. For the hydrogels, the effect of the con- tent of MBA and OP10AC on their tensile mechanical properties was studied by using o0 and Mc; also, the effect of the com- positions and temperature on their swelling behavior in distilled water was discussed in detail. In addition, hybrid HA-gels in- cluding a small quantity of MBA possessed the capabilities of secondary self-healing and remolding. In contrast with HA-gels prepared by the same compositions besides MBA, hybrid HA-gels showed good mechanical strength and long-term thermal stability in distilled water in the range of 25 to 80℃. Furthemore, hybrid HA-gels also avoided the self-deswelling behavior of HA-gels. The results show that the application fields of HA-gels will be greatly broadened after introducing a chemical cross-linking network.