Partially pyrolyzed poly(dimethylsiloxane)‐based networks: Thermal characterization and evaluation of the gas permeability

Abstract

In this investigation, the preparation and characterization of partially pyrolyzed membranes based on poly(dimethylsiloxane) (PDMS) are described. These membranes were obtained by the crosslinking of silanol‐terminated PDMS with multifunctional nanoclusters derived from the reaction of pentaerythritoltriacrylate with 2‐aminoethyl‐3‐aminopropyltrimethoxysilane and the in situ polycondensation of tetraethylortosilicate, followed by the thermal treatment of the resulting membranes at different temperatures. The partially pyrolyzed membranes were characterized with infrared spectroscopy, thermogravimetry, elemental analyses, dynamic mechanical analysis, small‐angle X‐ray scattering, and scanning electron microscopy. The membranes exhibited improvements in the thermal stability and mechanical strength. Even with distinct compositions with respect to the Si/O and Si/C ratios, the flexibility of these materials was maintained. The flux rates of the gases through the membranes were measured for N2, H2, O2, CH4, and CO2, at 25 °C. The permeability of the membranes changed with increases in the pyrolysis and oxidation temperatures. These membranes could be described as PDMS chains separated by inorganic clusters. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 299–309, 2007.

Nanoporous polymer – Clay hybrid membranes for gas separation

“…the PDMS membrane without adding Sepiolite, the selectivity was 2.65 for O 2 /N 2 and 5.75 for CO 2 /CH 4 . These values are comparable to those reported in the literature under similar conditions [35][36][37].…”

Study on the synthesis and application of silicone resin containing phenyl group

“…The thermal properties of silicone resin depend on the polymerization degree of the siloxane network and the molecular shape [24]. As reported previously, the thermal stability of polysiloxane increases with the increase in the crosslinking density [26][27][28][29]. The thermal degradation of the silicone resin increases with the increase in PhTES.…”

Tailoring amine functionalized hybrid ceramics to control CO2 adsorption

“…Heat treatment at low temperatures up to 300°C can already improve the mechanical and temperature stability of polysiloxanes as shown for polydimethylsiloxane gas separation membranes that are treated in argon and subsequently in air [16]. Moreover, partially pyrolyzed polysiloxane based membranes are shown to be advantageous for gas separation since the gas transport is altered by micropore formation during pyrolysis [17,18].…”