Porous Materials from Polyvinylidene Fluoride/Solvent Molecular Compounds

Abstract

Poly(vinylidene fluoride) (PVDF) can form molecular compounds with a large variety of solvents. The possibility of obtaining micropores (namely pores < 2 nm), as has been achieved with molecular compounds from syndiotactic polystyrene, was investigated in this paper. Three systems were investigated: PVDF/camphor, PVDF/ethyl acetoacetate, and PVDF/ethyl carbonate. Solvent extraction was performed under supercritical conditions with carbon dioxide. The sample morphology was observed by field-emission scanning electron microscopy. Crystalline structures of the dried samples were determined by X-Ray diffraction. Samples porosity was measured by mercury porosimetry and nitrogen physisorption. This study clearly shows that micropores similar to those created in syndiotatic polystyrene after solvent extraction are not present in PVDF samples produced under the same conditions. Only macropores are present.

Keywords:

• Molecular compounds
• Phase diagrams
• Poly(vinylidene Fluoride)
• Porosity