Study On The Porous Structure And Properties Of Adsorption Resins Modified With Polar Monomers

Porous poly (styrene-divinylbenzene) (ST-DVB) resins have been prepared using suspension polymerization with toluene and n-heptane as coporogens in the presence of acrylonitrile,methyl methacrylate as the third monomer. Pore shape,pore structure parameter and chemical structure were characterized by scanning electron microscopy, infrared spectrometer and N₂ sorption porosimetry, the dynamic adsorption properties for phenol were determined by chemical methods. When cross linking degree were at 60%,45%,40%, the influence of content of acrylonitrile,methyl methacrylate on their pore shape,specific surface,pore volume,average aperture and adsorptive capacity were studied. The influence of the monomers polarities on the pore structure and adsorptive capacity were studied respectively. Finally, adsorption phenol mechanism of the new resins was discussed.Experimental results suggested that pore shape,pore structure parameter have been large affected by the resins which were modified by acrylonitrile,methyl methacrylate, When the content of monomer ranged from 5% to 20%, the specific surface of ASD resins decreased, pore volume and average pore size increased. As the cross linking degree reduced to 40% and the acrylonitrile as diluent is 20%, the internal structure of resins appeared large hole and sinking hole was founded at the same time. The pore structure of MSD resin has also affected by the polar monomer MMA, which has the same trend as ASD, however, the degree of variability of MSD is less than ASDThe modifications of adsorbents for kinetic behaviors of phenol were studied. The differences kinds of monomers, content and comparing to unmodified resins with their adsorptive capacity were investigated. The results show that the dynamic adsorption quantity of ASD resins decreased with the content of acrylonitrile increasing which is in accordance with the change of specific surface, the results suggest the adsorptive capacity of phenol is mainly dependent on the pore structure. The dynamic adsorption quantity of MSD resins are increasing firstly, and then decreased with the content of acrylonitrile increasing. Basing on FTIR, we deduce that hydrogen bond function is one of the main propelling forces of the resins, which show that adsorptive capacity of resins is not only effected by pore structure, but also be effected by hydrogen bondfunction.