Synthesis of comb-type block copolymers by grafting through method: electrical properties and determination of activation energy via conductivity

Abstract

Poly[Ɛ-CL-b-(MMA-comb-EMA)]comb-type polymers were synthesized by ATRP and Ɛ-caprolactone macroinitiator and macromonomer. Methyl methacrylate macromonomer was synthesized from acylation reaction of methacryloyl chloride with PMMA ended 7-hydroxy coumarin. The macroinitiator was prepared from the reaction of chlorine acetyl chloride P(Ɛ-CL). The synthesized polymers were characterized by FT-IR, ¹H-NMR and ¹³C-NMR techniques. The average molecular weight and molecular weight distribution of polymers were measured by GPC method. Thermal properties of samples were studied by DSC/TGA techniques. Dielectric and Ac conductivity measurements were performed. Dielectric constant (ɛˈ), dielectric loss factor (ɛˈˈ) and conductivity behaviors of comb-type polymer were measured at room temperature between the frequency of 100–2000 Hz and over the temperature range 303–413 K at 1 kHz reported as compared with each other. Besides, their effects on the electrical properties by doping with EuCl₃ for some of the comb copolymers were and were investigated. The activation energy (E_a) was calculated from conductivity. We reported it was determined that the (ɛˈ) and (ɛˈˈ) values decreased with increasing frequency. There are also many application areas for comb polymers for example; nanotechnology, medicine. The aim of this study is to synthesize comb-type copolymers in different compositions and to investigate their electrical properties.

Keywords:

• Activation energy
• comb-type polymer
• dielectric properties
• Europium (III) chloride
• methyl methacrylate macromonomer

Additional information

Funding

The authors wish to thank FUBAP FF-11-35 for financial support of this project.