Chemical Journal of Chinese Universities ›› 2020, Vol. 41 ›› Issue (11): 2519-2525.doi: 10.7503/cjcu20200309

• Physical Chemistry • Previous Articles     Next Articles

Stimuli-responsive Fe3O4 Nanoparticle Modified by Conjugated Linoleic Acid

ZHANG Xinyu, WANG Hong, FANG Yun(), FAN Ye   

  1. (Key Laboratory of Synthetic and Biological Colloids(Ministry of Education),School of Chemical and Material Engineering,Jiangnan University,Wuxi 214122,China )
  • Received:2020-05-29 Online:2020-11-10 Published:2020-11-06
  • Contact: FANG Yun E-mail:yunfang@126.com
  • Supported by:
    Supported by the National Natural Science Foundation of China(21606107)

Abstract:

The surface of Fe3O4 nanoparticles was modified by small dosage of the natural unsaturated fatty acid, conjugated linoleic acid(CLA), instead of oleic acid to prevent the nanoparticles from secondary agglo-meration, oxidization and thus loss of magnetism, and to further improve thermal instability of the modified fatty acid layer. The stability of the modified layer was enhanced by means of self-crosslinking of conjugated double bond of CLA molecules, by which the modified particles could be responsive to the pH stimulus besides the magnetic stimulus. The size and morphology of the modified Fe3O4 NPs was imaged by TEM, the coordinationmodes by ATR-FTIR, the dosage of CLA by TG, the surface wettability by θ angle analysis, moreover the droplet size and size distribution of Pickering emulsion stabilized by the modified particles were photographed by large-depth-of-field microscope. The experimental results indicated that the modified particles are well- dispersed relying on a thin and stable, hydrophobic surface showing obvious dual pH/magnetic responsiveness. Pickering emulsion could be stabilized by small dosage of the modified particles(mass fraction 0.05%) and shown the emulsion characteristics of high internal oil phase(oil volume fraction 80%), switchable by a pH trigger, and migratable in an external magnetic field. A simulation experiment shows that the emulsion can effectively extract and separate organic pollutant in the aqueous phase.

Key words: Conjugated linoleic acid, Fe3O4 nanoparticles, Surface modification, Stimuli-responsive, Picke-ring emulsion

CLC Number: