Surface-initiated Atom Transfer Radical Polymerization and Solution Intercalation Methods for Preparation of Cellulose-G-PS-G-PAN/MMT Bionanocomposite

Abstract

Cellulose was modified by polystyrene (PS) and polyacrylonitrile (PAN) via free radical and living radical polymerization, and then cellulose was used as the matrix in the preparation of polymer/clay nanocomposite, through a solution intercalation method. For this purpose, first, the graft polymerization of styrene (St) onto cellulose fibers was performed by using suspension polymerization and the free-radical polymerization technique in the presence of potassium persulfate (PPS). Second, the synthesized cellulose-graft-polystyrene was brominated by N-bromosuccinimide (NBS) to obtain polymers with bromine a group. Third, the brominated cellulose fibers were used as macroinitiators in the atom transfer radical polymerization (ATRP) of acrylonitrile (AN) in the presence of CuCl / 2, 2’-bipyridine (Bpy) catalyst system in THF solvent at 90˚C to prepare the cellulose-graft-polystyrene–graft–polyacrylonitrile. Forth, for preparing the modified clay, Na-MMT was mixed with hexadecyl trimethyl ammonium chloride salt. Finally, cellulose-graft-polystyrene–graft–polyacrylonitrile/organoclay bionanocomposite was prepared in CCl4 by a solution intercalation method. Then, the structure of the obtained terpolymer was investigated by FT-IR, DSC, TGA, XRD, and SEM techniques. Moreover, the structure of the bionanocomposite was probed by XRD, SEM, and TEM images.

Keywords

• bionanocomposite
• cellulose
• styrene
• atom transfer radical polymerization
• modified clay