The effects of the silanization of multi-walled carbon nanotubes and graphene nanoplatelets with 3-APTES on thermal, mechanical and electrical properties of epoxy nanocomposites were investigated. Nanocomposites containing pristine, oxidized and silanized nanoparticles of multi-walled carbon nanotubes or graphene nanoplatelets at two different concentrations (0.15 and 0.50 vol.%) were prepared by in situ polymerization without using solvents. The functionalized nanoparticles were characterized by Fourier-transform infrared, X-ray photoelectron spectroscopy, Raman spectroscopy and transmission electron microscope techniques. The oxidation and the silanization on the surface of both nanoparticles were confirmed by Fourier-transform infrared, X-ray photoelectron spectroscopy, Raman and transmission electron microscope analysis. The thermal properties of all studied materials were analyzed by differential scanning calorimetry and the mechanical properties by nanoindentation. The addition of both nanoparticles (pristine and functionalized) into the matrix did not show significant variations on thermal properties, but decreased values for glass transition temperature (Tg) compared to the neat resin. Higher values for modulus of elasticity and hardness of epoxy/nanocomposites were obtained when silanized multi-walled carbon nanotubes or oxidized graphene nanoplatelets were added into the matrix. Adding 0.15 vol.% of silanized multi-walled carbon nanotubes the modulus of elasticity increased in approximately 60%, whereas 0.50 vol.% this increase was greater than 90% compared to the neat resin. While adding 0.15 vol.% of oxidized graphene nanoplatelets, the modulus of elasticity increased approximately 83%, whereas 0.50 vol.% this increase was greater than 88% compared to the neat resin. The formation of percolating networks has been achieved only by pristine multi-walled carbon nanotubes addition at a concentration of 0.50 vol.% and by silanized graphene nanoplatelets at a concentration of 0.15 vol.%. However, for both carbon-based nanoparticles conductivities on the order of 10⁻⁷ S/m for frequencies near 100 Hz were observed.

The separation of organic components has become increasingly important as one of the applications of pervaporation membranes. This interest is due to their application in areas that include the recovery of ethanol from a fermentation broth as a lower-energy-cost alternative to classical separation processes such as distillation. The present work seeks to evaluate the separation of ethanol produced from banana waste (unused fruit and pulp) using pervaporation. Different operating conditions, such as flow rate, temperature, feed composition and permeate pressure were studied in commercial hydrophobic polydimethylsiloxane (PDMS) membranes. The experiments were compared to a standard solution (ethanol/water) to determine differences in the results due to the presence of fermentation by products. As expected, the best results for the recovery of ethanol were obtained at lower feed and the flux increases with increasing ethanol concentration in the feed, whereas the selectivity decreases. When the evaluated characteristics were compared with the fermentation broth, the following increases were observed: a 20% increase in the enrichment factor and a 75% increase in ethanol concentration in the permeate. The results are considered to be promising and indicate the feasibility of using pervaporation in the production of bioethanol from banana waste