Miscibility of Poly(Methyl Methacrylate) and Poly(Vinylidene Fluoride) Examined by Thermally Stimulated Depolarization Current and Dielectric Relaxation Spectroscopy

Abstract

Samples of poly(methyl methacrylate) (PMMA), poly(vinylidene fluoride) (PVDF) and melt blended PMMA/PVDF with weight ratios 4/1 and 3/2 were characterized by thermally stimulated depolarization currents (TSDC) in the temperature interval 123-303 K and by dielectric relaxation spectroscopy (DRS) in the frequency window 10⁻² − 106 Hz in the temperature interval 153-423 K. The TSDC thermograms and DRS profiles of the samples showed the two types of conducnivity – non-cooperative and cooperative. The experimental DRS data in the vicinity of the glass transition temperature, T_g, were quantitatively fitted to the Havriliak-Negami function and values of the maximum relaxation time were fitted to the Vogel-Tammann-Fulcher equation. Higher values of the strength index D, of the dielectric relaxation strength Δε and of the σ_ac conductivity for the binary blends were considered as experimental evidence for nanoscale composition heterogeneities originating from strong specific interactions between the PMMA and PVDF. Therefore, we suggest the PMMA/PVDF blends will be usefull as effective materials for the manufacture of lithium-ion batteries, electrostatic capacitors with superior energy storage performance, polymer composite electrolytes for solar cells, etc.

Keywords:

• dielectric relaxation spectroscopy
• poly(methyl methacrylate)
• poly(vinylidene fluoride)
• thermally stimulated depolarization currents

Acknowledgments

Thank are due to Dr. Ye. Mamumya for TOM studies and Prof. P. Pissis for help with TSDC and DRS measurements.

Conflict of interest

The authors declare that they have no conflict of interest.

Additional information

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sector.