Abstract
The physical mixture between polymers can be an alternative to obtain materials with specific properties. The polymeric blend obtained by the mixture of sulfonated poly(ether ether ketone) [SPEEK], protonic conductor, and polyaniline [PANI], electronic conductor, can result in a mixed conductive membrane. The objective of this work was to obtain and evaluate the physical-chemical properties of mixed conductive SPEEK/PANI polymeric membranes to be applied on the membrane/electrode interface in fuel cells. For so, two membrane preparation methodologies were studied: i) dissolution of the polymers in a common solvent and ii) PANI synthesis on SPEEK acid matrix. Aspects relating to PANI
protonation with SPEEK in solution and as polymeric matrix, the solvent effect and necessary amount of SPEEK in the system to obtain conductive PANI were evaluated. Specific membrane properties like permeability, diffusion, solubility and gas selectivity, morphology, protonic conductivity, electronic conductivity and thermal stability confirmed the viability of the proposed system. The interface morphology between carbon electrode and SPEEK/PANI membrane showed stability and homogeneity. The binary permeability tests, showed promising results in concern to hydrogen and oxygen selectivities. Mixed conduction was verified by attainment electronic and protonic conductions in the order of 10-5 S cm-1 and 6 10-2 S cm-1, respectively, making the system able to participate on the transport of electrons and protons.
