Multifunctional porous poly (vinylidene fluoride)-graft-poly (butyl methacrylate) with good Li⁺ ion conductivity

Abstract

PnBMA is grafted on PVDF using ATRP in NMP solution at 90 °C and characterized by means of 1D and 2D NMR. ¹⁹F NMR spectra clearly reveal that the attack occurs on the head-head >CF₂ groups. Cast PB films show a honeycomb-patterned porous microstructure, and the "breath-figure" model is used to explain pore formation. FT-IR spectra suggest a supramolecular interaction between >C=O groups of PnBMA and >CF₂ groups of PVDF. Storage modulus, loss modulus and stress at break decrease with graft conversion, but the strain at break increases significantly. The toughness of the copolymers also increases dramatically (882%). The porous materials can be applied as solid-state electrolytes (Li⁺-doped) with good ionic conductivity (10⁻⁵ S · cm⁻¹).