Tunable ultrathin membranes with nonvolatile pore shape memory.
The concept of a responsive nanoporous thin-film gel membranes whose pores could be tuned to a desired size by a specific "molecular signal" and whose pore geometry becomes "memorized" by the gel is reported. The ∼100 nm thick membranes were prepared by dip-coating from a solution mixture of a random copolymer comprising responsive and photo-cross-linkable units and monodisperse latex nanoparticles used as a sacrificial colloidal template. After stabilization of the films by photo-cross-linking the latex template was removed, yielding nanoporous structures with a narrow pore size distribution and a high porosity. The thin-film membranes could be transferred onto porous supports to serve as tunable size-selective barriers in various colloids separation applications. The pore dimensions and hence the membrane's colloidal-particle-size cutoff were reversibly regulated by swelling-shrinking of the polymer network with a specially selected low-molar-mass compound. The attained pore shape was "memorized" in aqueous media and "erased" by treatment in special solvents reverting the membrane to the original state.
†Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, New York 13699, United States.
Hidenori
H
Kuroki
†Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, New York 13699, United States.
Crescent
C
Islam
†Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, New York 13699, United States.
Igor
I
Tokarev
§Department of Chemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada.
Heng
H
Hu
§Department of Chemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada.
Guojun
G
Liu
†Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, New York 13699, United States.|‡Nanostructured Materials Lab, University of Georgia, Athens, Georgia 30602, United States.
Sergiy
S
Minko
D008422:Materials Testing; D008567:Membranes, Artificial; D058608:Nanopores / Q000648:ultrastructure*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D011108:Polymers / Q000737:chemistry*; D016062:Porosity; D014462:Ultrafiltration / Q000379:methods*
D008567:Membranes, Artificial; D011108:Polymers
nanostructure; pore memory; responsive membrane; size-selective filtration; template