Polydimethylsiloxane Membranes Containing Multi-walled Carbon Nanotubes for Gas Separation

• Published in: Materials research (São Carlos, São Paulo, Brazil) São Paulo, Brazil), 2017-11, Vol.20 (6), p.1454-1460
• Main Authors: Silva, Elisângela Aparecida da, Windmöller, Dario, Silva, Glaura Goulart, Figueiredo, Kátia Cecília de Souza
• Format: Article
• Language: English
• Subjects: Carbon; Carbon dioxide; ENGINEERING, CHEMICAL; Gas separation; Infrared analysis; MATERIALS SCIENCE, MULTIDISCIPLINARY; Membranes; METALLURGY & METALLURGICAL ENGINEERING; Methane; mixed matrix membranes; Multi wall carbon nanotubes; multi-walled carbon nanotubes; Nanotubes; Phase separation; Polydimethylsiloxane; Positron annihilation; Scanning electron microscopy; Silicone resins; Thermogravimetric analysis; X-ray diffraction
• ISSN: 1516-1439; 1980-5373; 1980-5373
• DOI: 10.1590/1980-5373-mr-2016-0825

Polydimethylsiloxane (PDMS) membranes with different concentrations of multi-walled carbon nanotubes were prepared in order to evaluate their gas separation performances. Mixed matrix membranes were characterized by scanning electron microscopy, thermogravimetric analysis, Fourier transformed infrared, positron annihilation lifetime and Raman spectroscopies and X-ray diffraction. The permeabilities to CO2, CH4, N2 and O2 were determined. No phase separation was noticed. For carbon nanotubes content of 1 wt%, it was shown a decrease in membrane permeability with slight increase in ideal selectivity, compared to pure PDMS. However, the increase in the filler load up to 6.7 wt% increased the free volume average size of the membranes, improving the contribution of the diffusion to the transport and decreasing ideal selectivities of CO2/CH4, CO2/N2 and O2/N2.