Exfoliated Poly (styrene-co-urethane) Grafted - Polymethylmethacrylate /Layered Double Hydroxide Nanocomposite Synthesized by Metal Catalyzed Living Radical Polymerization and Solvent Blending Method

Abstract

In this research, a facile strategy was employed for the synthesis of terpolymer derivatives from polystyrene (PSt), polyurethane (PU), poly (methyl methacrylate) (PMMA), and its organo-modified Zn Al LDH (layered double hydroxide) by in situ ATRP. For this purpose, firstly, LDH nanoparticles were modified with sodium dodecyl sulfonate (SDS) by the anion exchange reaction of Zn-Al-LDH. Secondly, PU macroinitiator was obtained from a solvent composed of 9-decen-1-ol and used in controlled graft copolymerization of styrene to afford PU-co-Pst copolymer. Then, the synthesized PU-co-St was brominated by N-bromosuccinimide (NBS) to obtain a copolymer with the bromine group. In the following, living radical polymerization of MMA was done in the presence of brominated PU-co-St and CuBr /Bpy (2, 2’-bipyridine catalyst to prepare the (PMMA-g-PSt-g-PU) terpolymer. Finally, (PMMA-g-PSt-g-PU)/ ZnAl LDH nanocomposite was successfully synthesized by the solution intercalation method. FE-SEM images showed that surface morphologies of Zn-Al (SDS) and Zn-Al-LDH leads to sheet-like and hexagonal morphology. Investigation of thermal properties using DSC and TGA exhibited that the prepared (PMMA-g-PSt-g-PU) /Zn-Al-LDH nanocomposite has a higher thermal stability compared to neat PU. The synthesized terpolymer and (PMMA-g-PSt-g-PU)/ Zn-Al-LDH nanocomposite can be used as a reinforcing agent for polymeric nanocomposites due to its high LDH properties.