Synthesis and Characterization of Silica−Poly(N-isopropylacrylamide) Hybrid Membranes: Switchable Molecular Filters
| Autor: | G. V. Rama Rao, Gabriel P. Lopez, Qing Xu, S. S. Balamurugan, Huifang Xu, Matthew E. Krug |
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| Rok vydání: | 2002 |
| Předmět: |
chemistry.chemical_classification
Materials science General Chemical Engineering Transition temperature General Chemistry Polymer Permeation chemistry.chemical_compound Differential scanning calorimetry Membrane chemistry Chemical engineering Polymer chemistry Materials Chemistry Poly(N-isopropylacrylamide) Solubility Hybrid material |
| Zdroj: | Chemistry of Materials. 14:5075-5080 |
| ISSN: | 1520-5002 0897-4756 |
| DOI: | 10.1021/cm020627b |
| Popis: | Hybrid materials consisting of stimuli-responsive polymers (SRPs) in an inorganic matrix have the potential for use in a variety of applications as switchable or tunable membranes, coatings, adsorbents, and solute reservoirs. Poly(N-isopropylacrylamide) (PNIPAAM) is an SRP that exhibits inverse solubility behavior in water upon an increase in temperature through a transition from a hydrophilic to a hydrophobic state. In an earlier communication, we demonstrated that when PNIPAAM is encapsulated in a silica matrix by a sol−gel process, the resultant hybrid material can function as a switchable molecular filter. In this paper, we present detailed investigation and characterization of these membranes, which exhibit reversible on/off permeation behavior, above and below the transition temperature of PNIPAAM, respectively. Scanning and transmission electron microscopic studies show that the membranes are highly homogeneous, and phase separation of the polymers is not observed. Differential scanning calorimetry... |
| Databáze: | OpenAIRE |
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