preparation and characterization of semi-ipn magnetic nanocomposite hydrogels based on partially hydrolyzed polyacrylamide/guar gum/ fe3o4@sio2 nps for enhanced oil recovery

The synthesis and characterization of semi-ipn partially hydrolyzed polyacrylamide (hpam)/ guar gum (gg) /core-shell fe3o4@sio2 for the development of hydrogel system used in enhanced oil recovery is described. nanocomposite hydrogels were synthesized in an aqueous solution by an in situ simultaneous cross-linking reactions between partially hydrolyzed polyacrylamide chains and chromium acetate as an ionic crosslinker in the presence of gg. the structural, surface and magnetic characteristics of the semi-ipn magnetic nanocomposite hydrogels were investigated by emission scanning electron microscopy(sem), powder x-ray diffraction(xrd), fourier transform infrared(ft-ir), vibrating sample magnetometer(vsm) and thermogravimetric analysis (tga). the nanocomposite gels were prepared with low crosslinker concentration (200 ppm chromium acetate). the rheological analysis showed that the storage modulus of semi-ipn nanocomposite hydrogels increased with the addition of 1 wt% nps, but further due to participation in the cross-linking reaction and as a result of increasing the cross-linking density, water swelling was reduced. considering that nanocomposite hydrogels have a higher resistance in synthetic oil reservoir water compared to unfilled hydrogels, which is a desirable feature. the results showed that the new semi-ipn magnetic nanocomposite hydrogels could be potentially suitable for the area of chemically enhanced oil recovery.