Structural Insights into Water-Based Spider Silk Protein-Nanoclay Composites with Excellent Gas and Water Vapor Barrier Properties.
Nature reveals a great variety of inorganic-organic composite materials exhibiting good mechanical properties, high thermal and chemical stability, and good barrier properties. One class of natural bio-nanocomposites, e.g. found in mussel shells, comprises protein matrices with layered inorganic fillers. Inspired by such natural bio-nanocomposites, the cationic recombinant spider silk protein eADF4(κ16) was processed together with the synthetic layered silicate sodium hectorite in an all-aqueous setup. Drop-casting of this bio-nanocomposite resulted in a thermally and chemically stable film reflecting a one-dimensional crystal. Surprisingly, this bio-nanocomposite coating was, though produced in an all-aqueous process, completely water insoluble. Analyzing the structural details showed a low inner free volume due to the well-oriented self-assembly/alignment of the spider silk proteins on the nanoclay surface, yielding high oxygen and water vapor barrier properties. The here demonstrated properties in combination with good biocompatibility qualify this new bio-nanocomposite to be used in packaging applications.
Elena
E
Doblhofer
Jasmin
J
Schmid
Martin
M
Rieß
Matthias
M
Daab
Magdalena
M
Suntinger
Christoph
C
Habel
Hendrik
H
Bargel
FRM II und Physik-Department E21, Technische Universität München , James-Franck-Straße 1, Garching D-85748, Germany.
Christoph
C
Hugenschmidt
Sabine
S
Rosenfeldt
Josef
J
Breu
Thomas
T
Scheibel
D053761:Nanocomposites; D047011:Silk / Q000737:chemistry*; D013227:Steam; D014835:Volatilization; D014867:Water
D047011:Silk; D013227:Steam; D014867:Water
barrier coatings; bio-nanocomposites; layered silicates; spider silk; water-based packaging coatings