Catalytic Activity of Maghnite-H+ in the Synthesis of Polyphenylmethylsiloxane under Mild and Solvent-free Conditions

In this study, a new and easy strategy was discussed for the purpose of synthesizing of a polymer of phenylmethylcyclosiloxane type (PPMS). The cationic ring opening polymerization of triphenyltrimethylcyclotrisiloxane (D3Ph,Me) was initiated by a solid, efficient and environmentally-friendly catalyst called Maghnite-H+. Maghnite-H+ is a natural clay composed essentially of montmorillonite, it is activated with an acid treatment by replacing the interlayer ions by protons, that results to the increase of the basal space, this may be confirmed by XRD analysis. The reaction was carried out without solvent at different temperatures and for different periods of time, using also several catalyst contents. Subsequently, the operating conditions were opted in order to obtain a maximum yield of the linear polymer and a high average molecular mass as well. The structure of polymers obtained was confirmed by IR analysis. 1H NMR and 13C NMR analyzes were used to follow the crosslinking of polymer chains over time. The thermal behavior was investigated by DSC analysis. The average molecular mass and the polydispersity indices were determined by GPC

Highly Conductive and Soluble Polymer Synthesized by Copolymerization of Thiophene with Para-Methoxybenzaldehyde Using Clay Catalyst

This present research focuses on the synthesis of a new conducting polymer based on the copolymerization of thiophene with para-methoxybenzaldehyde, using a clay as an ecologic catalyst named Maghnite-H+. The catalysis of the reaction by Maghnite-H+ can confer it important benefits, such as the green environment aspect. The reaction was carried out in dichloromethane as a solvent. The new copolymer obtained is a poly (heteroarylene methines) small bandgap polymers precursor. It can be considered as a useful model system for examining the impacts of π-conjugation length on the electronic properties of this type of conjugated polymers. The measurements of the electrical conductivity gave a value of order of 0.0120 W.cm-1, allowing its use in various important applications. The characteristics of the molecular structure and the thermal behavior of the conducting polymer obtained are also discussed using different methods of analysis, such as: proton nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR) spectroscopy, ultraviolet/visible spectroscopy, and thermal gravimetric analysis (TGA). Copyright © 2019 BCREC Group. All rights reserve