NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Amorphous Silk Fibroin Membranes for Separation of CO2Amorphous silk fibroin has shown promise as a polymeric material derivable from natural sources for making membranes for use in removing CO2 from mixed-gas streams. For most applications of silk fibroin, for purposes other than gas separation, this material is used in its highly crystalline, nearly natural form because this form has uncommonly high tensile strength. However, the crystalline phase of silk fibroin is impermeable, making it necessary to convert the material to amorphous form to obtain the high permeability needed for gas separation. Accordingly, one aspect of the present development is a process for generating amorphous silk fibroin by treating native silk fibroin in an aqueous methanol/salt solution. The resulting material remains self-standing and can be prepared as thin film suitable for permeation testing. The permeability of this material by pure CO2 has been found to be highly improved, and its mixed-gas permeability has been found to exceed the mixed-gas permeabilities of several ultrahigh-CO2-permeable synthetic polymers. Only one of the synthetic polymers poly(trimethylsilylpropyne) [PTMSP] may be more highly permeable by CO2. PTMSP becomes unstable with time, whereas amorphous silk should not, although at the time of this reporting this has not been conclusively proven.
Document ID
20090020545
Acquisition Source
Johnson Space Center
Document Type
Other - NASA Tech Brief
Authors
Aberg, Christopher M.
(North Carolina State Univ. Raleigh, NC, United States)
Patel, Anand K.
(North Carolina State Univ. Raleigh, NC, United States)
Gil, Eun Seok
(North Carolina State Univ. Raleigh, NC, United States)
Spontak, Richard J.
(North Carolina State Univ. Raleigh, NC, United States)
Hagg, May-Britt
(Norwegian Univ. of Science and Technology Norway)
Date Acquired
August 24, 2013
Publication Date
May 1, 2009
Publication Information
Publication: NASA Tech Briefs, May 2009
Subject Category
Man/System Technology And Life Support
Report/Patent Number
MSC-24032-1
Report Number: MSC-24032-1
Distribution Limits
Public
Copyright
Public Use Permitted.
No Preview Available