Influence of the Preparation Method and Photo-Oxidation Treatment on the Thermal and Gas Transport Properties of Dense Films Based on a Poly(ether-block-amide) Copolymer

Abstract

Dense films based on the hydrophobic Pebax®2533 were prepared by using solution casting in different solvents as well as compression molding and subjected to photo–aging under ultraviolet (UV) irradiation. The influence of the preparation method, including the casting solvents, as well as the UV irradiation time selected to treat the samples, were evaluated in terms of permeation rates of pure gases (CO2, N2, O2, CH4, He, and H2). The transport data were correlated with the microstructure and surface properties by using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), as well as water contact angle measurements. The obtained results showed that a controlled photo-oxidation process reduces the hydrophobicity of the Pebax®2533 films, increasing their permeability without compromising their integrity.

Heterogenized Imidazolium-Based Ionic Liquids in Pebax®Rnew. Thermal, Gas Transport and Antimicrobial Properties

“…The neat Pebax is quite permeable, with permeability values close to those reported for Pebax ® 2533 [ 23 ]. These results depend on the large amount of soft PE blocks that, owing to their high chain mobility, are gas permeable, while the hard PA segments provide mechanical stability.…”

“…Gas permeation tests on flat dense membranes were carried out at with single gases (H 2 , He, N 2 , O 2 , CH 4 and CO 2 ) in a fixed volume/pressure increase instrument (Elektro & Elektronik Service Reuter, Germany) at 25 °C [ 23 ]. Before each experiment, the membrane samples were carefully evacuated using a turbo molecular pump to remove previously dissolved species.…”

Enhancing Gas Permeation Properties of Pebax® 1657 Membranes via Polysorbate Nonionic Surfactants Doping

“…Gas permeation rates were measured on the prepared flat dense membranes in a fixed volume/pressure increase instrument described elsewhere [13]. Before each test, the membrane samples were carefully evacuated with a series of membrane and turbo molecular pumps to remove previously dissolved species.…”

“…The membrane was exposed to the feed gas, and the pressure in the fixed permeate volume was monitored by a pressure transducer. The slope of the time-pressure curve, considering steady-state conditions, provided the Permeability coefficient (P) as described in [13].…”

Effect of Physical Aging on Gas Transport in Asymmetric Polyimide Hollow Fibers Prepared by Triple-Orifice Spinneret

“…Each HF sample was exposed to the feed gas, while the pressure increase in the permeate volume, caused by the gas permeation through the membrane, was monitored by a pressure transducer over time. The pressure signal was correlated to the amount of gas permeated through the sample, as described in Reference [23], evaluating the gas permeance, expressed in gas permeance units (GPU; 1 GPU = 10 −6 cm 3 (standard temperature and pressure (STP))/(cm 2 •s•cm Hg)). The ideal permselectivity was calculated as the ratio of pure gas permeance coefficients.…”