In this paper, new thermo-sensitive poly(N-isopropylacrylamide-co-acrylic acid) magnetic nanocom-posites (P(NIPAM-co-AAc)/Fe3O4/FePc) were prepared by in situ dispersion polymerization. The newFe3O4/FePc hybrid magnetic nanoparticles were fabricated by solvent-thermal route from 4,4-((propane-2,2-diylbis(4,1-phenylene))bis(oxy))diphthalonitrile and FeCl3.6H2O. The morphology, structure andproperties of the Fe3O4/FePc hybrid nanoparticles were investigated. The results exhibited the spher-ical structures of hybrid nanoprticles with diameters of 30–70 nm and superparamagnetic property. TGAresults revealed that about 22.3% of the phthalocyanine oligomer was incorporated into the resultinghybrid magnetic nanoparticles. The magnetic nanocomposite hydrogels were characterized by means ofFourier transform infrared (FT-IR) spectra, scanning electron microscopy (SEM), X-ray diffraction (XRD)spectroscopy, thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM) and differentialscanning calorimetry (DSC). The lower critical solution temperatures (LCST) of the magnetic nanocom-positehydrogelsin water were measured by DSC and the LCST behavior of them were studied. The resultsshowed that the LCST of the hydrogels were influenced by the content of Fe3O4/FePc hybrid nanoparti-cles. The LCST of P(NIPAM-co-AAc)/Fe3O4/FePc-2% and P(NIPAM-co-AAc)/Fe3O4/FePc-4% were at about38 and 41◦C, respectively. The results showed that an increase in Fe3O4/FePc hybrid nanoparticles contentmakes the LCSTs of the hydrogels increase to near the human body temperature.
