Preparation And Characterization Of Alkylphosphonium Montmorillonite As Nanofiller For Polymethyl Methacrylate Acid Composites

Abstract

Sodium montmorillonite (Na+ -MMT) is one of the natural clay uses worldwide as nano filler in polymer nanocomposite. Na+-MMT is naturally hydrophilic in nature and cannot dispersed easily in organic polymer matrix as polymer has hydrophobic characteristic. Thus surface of MMT must undergo certain modifications to improve its ability to disperse in polymer matrix in the fonn of organophilic MMT (OMMT). Currently commercial OMMT are modified from alkyl ammonium surfactant, which has low thennal stability which unable them to withstand high temperature for thermal polymer processing. Considering steric tolerance of phosphorus atom by participation of its low energy d-orbitals, in breaking and fonnation of bond, alkyl phosphonium surfactants are propose in this study as an altemative surface modifier to alkylammonium which expected to increase the thermal stability of modified clay. Triisobutyl(methyl)phosphonium (TBMP) and tetrabutylphosphonium chloride (TBP) were used as surface modifier in the modification of Na+-MMT via ion exchange reaction fonning OMMT's. (TBMP-MMT and TBP-MMT). The Na+­ MMT, OMMT and commercial MMT (Cloisite 93A) were characterized and compared based on their elemental composition (CHNS), chemical structure (FTIR, BET analysis) and morphology (XRD), and them1al properties (TGA).