The hydrophobic association hydrogels (HA gels) were synthesized through micellar copolymerization of acrylic acid (AA) and a small amount of octadecyl methacrylate (OMA) in solution containing sodium dodecyl sulphate (SDS).The associated micelles consisting of surfactants and hydrophobes acted as physical cross-linking points in the network structure of HA gels.The mechanical properties of HA gels were measured by one-way tensile experiments

and the results confirmed the high toughness of asobtained hydrogels.The mechanical properties were associated with the effective network chain density and the effective cross-linking point contents.With increasing the content of hydrophilic or hydrophobic monomer in the HA gels

the strength of HA gels all increased while the elongation at break all decreased.Furthermore

the swelling behavior of HA gels in aqueous solutions at different pH values was also investigated.It was found that the HA gels possessed unusual swelling behavior.The swelling process could be divided into three stages:namely

the gel erosion stage

swelling equilibrium stage and gel disruption stage.At strong acidity

the swelling of gel was restrained

and the gel disruption stage did not appear.At strong alkaline condition

the swelling of gels was accelerated so that the swelling equilibrium stage was overpassed.Last

the salt effect restrained the swelling of HA gels

however

in SDS aqueous solutions

the SDS would drag the hydrophobically modified polymers into solution

then new association network was formed

and thus the solution was thickened.The hydrophobic association hydrogels (HA gels) were synthesized through micellar copolymerization of acrylic acid (AA) and a small amount of octadecyl methacrylate (OMA) in solution containing sodium dodecyl sulphate (SDS).The associated micelles consisting of surfactants and hydrophobes acted as physical cross-linking points in the network structure of HA gels.The mechanical properties of HA gels were measured by one-way tensile experiments

and the results confirmed the high toughness of asobtained hydrogels.The mechanical properties were associated with the effective network chain density and the effective cross-linking point contents.With increasing the content of hydrophilic or hydrophobic monomer in the HA gels

the strength of HA gels all increased while the elongation at break all decreased.Furthermore

the swelling behavior of HA gels in aqueous solutions at different pH values was also investigated.It was found that the HA gels possessed unusual swelling behavior.The swelling process could be divided into three stages:namely

the gel erosion stage

swelling equilibrium stage and gel disruption stage.At strong acidity

the swelling of gel was restrained

and the gel disruption stage did not appear.At strong alkaline condition

the swelling of gels was accelerated so that the swelling equilibrium stage was overpassed.Last

the salt effect restrained the swelling of HA gels

however

in SDS aqueous solutions

the SDS would drag the hydrophobically modified polymers into solution

then new association network was formed

and thus the solution was thickened.