MULTI-SITE PHASE TRANSFER CATALYZED RADICAL POLYMERIZATION OF n-BUTYL METHACRYLATE: A KINETIC STUDY

Abstract

The kinetics and mechanism of radical polymerization of n-butyl methacrylate (n-BMA) using potassium peroxydisulfate (PDS) as a water-soluble initiator in the presence of 1,4-bis(tributyl methyl ammonium) benzene dichloride (TBMABDC) as a multi-site phase transfer catalyst (MPTC) were studied. The polymerization reactions were carried out under oxygen-free, unstirred conditions at a constant temperature of 60° ± 1°C in cyclohexane-water two-phase systems. The dependence of rate of polymerization (Rp) on concentrations of monomer, initiator, and catalyst, volume fraction of aqueous phase, solvent polarity, and temperature was determined. The reaction order with respect to monomer, initiator, and multi-site phase transfer catalyst was found to be 0.50, 1.0, and 0.52 respectively. Based on the experimental results, an appropriate reaction mechanism has been proposed and its significance discussed. The prepared polymer was characterized with spectral analysis.

Keywords:

• Kinetics
• Multi-site phase transfer catalyst
• n-Butyl methacrylate
• Radical polymerization

Notes

Reaction conditions: [n-BMA]: 2.0 mol · dm⁻³; [K₂S₂O₈]: 2.0 × 10⁻² mol · dm⁻³; [TBMABDC]: 2.0 × 10⁻² mol · dm⁻³; [H⁺]: 0.5 mol · dm⁻³; [μ]: 0.2 mol · dm⁻³; temperature: 60°C.

Reaction conditions: [K₂S₂O₈]: 2.0 × 10⁻² mol · dm⁻³; [TBMABDC]: 2.0 × 10⁻² mol · dm⁻³; [H⁺]: 0.5 mol · dm⁻³; [μ]: 0.2 mol · dm⁻³; temperature: 60°C.

Reaction conditions: [n-BMA]: 2.0 mol · dm⁻³; [TBMABDC]: 2.0 × 10⁻² mol · dm⁻³; [H⁺]: 0.5 mol · dm⁻³; [μ]: 0.2 mol · dm⁻³; temperature: 60°C.

Reaction conditions: [n-BMA]: 2.5 mol · dm⁻³; [K₂S₂O₈]: 2.0 × 10⁻² mol · dm⁻³; [H⁺]: 0.5 mol · dm⁻³; [μ]: 0.2 mol · dm⁻³; temperature: 60°C.

Reaction conditions: [n-BMA]: 2.0 mol · dm⁻³; [K₂S₂O₈]: 2.0 × 10⁻² mol · dm⁻³; [TBMABDC]: 2.0 × 10⁻²mol · dm⁻³; [H⁺]: 0.5 mol · dm⁻³; [μ]: 0.2 mol · dm⁻³.

Reaction conditions: [n-BMA]: 2.0 mol · dm⁻³; [K₂S₂O₈]: 2.0 × 10⁻² mol · dm⁻³; [TBMABDC]: 2.0 × 10⁻² mol · dm⁻³; [H⁺]: 0.5 mol · dm⁻³; [μ]: 0.2 mol · dm⁻³.