Multiseale porosity from thermoreversible poly(vinylidene fluoride) gels in diethyl azelate

Poly(vinylidene fluoride) (PVF2) produces thermoreversible gels in a series of diesters. The polymer-solvent complexation occurred for intermittent number of carbon atoms n >= 2 and the enthalpy of complexation increased with increasing n. The gels were dried by replacing the diesters with low boiling solvent like cyclohexane (bp. 80 degrees C) and methylcyclohexane (bp. 99 degrees C). The porosity of the dried gels was measured using Poremaster-60. For PVF2-DEAZ gel meso and macro porosity have been observed. The former pore dimensions have been attributed for polymer-solvent complexation while the macroporosity has been attributed for caging of solvent between the PVF2 fibrils The porosity measured from nitrogen adsorption isotherms using BJH method indicate presence of minimum pore diameter of 3.8 nm for the 10% dried gel Of PVF2.