Phototunable Cross-Linked Polysiloxanes
| Autor: | Amanda S. Fawcett, Timothy C. Hughes, Laura Zepeda-Velazquez, Michael A. Brook |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
chemistry.chemical_classification
Materials science Polymers and Plastics Polymer science Organic Chemistry Modulus Thermosetting polymer 02 engineering and technology Polymer 010402 general chemistry 021001 nanoscience & nanotechnology Elastomer 01 natural sciences Silicone oil 0104 chemical sciences Inorganic Chemistry chemistry.chemical_compound Silicone chemistry Covalent bond Polymer chemistry Materials Chemistry Thermoplastic elastomer 0210 nano-technology |
| Zdroj: | Macromolecules. 48:6499-6507 |
| ISSN: | 1520-5835 0024-9297 |
| DOI: | 10.1021/acs.macromol.5b01085 |
| Popis: | Silicone elastomers are normally thermoset materials. While their inherent properties make them highly valuable, it would be of interest to develop stimuli-responsive silicones whose properties could be reversibly tuned at will. In the case of silicone polymers, a particularly interesting trigger is light, since silicone elastomers can readily be formulated to be transparent. We describe the utilization of coumarin-modified silicones for this purpose. On their own, the presence of coumarin groups converts silicone oils into thermoplastic elastomers through physical (noncovalent) cross-linking. UV-irradiation permits covalent cross-linking through [2 + 2] cycloadditions and is accompanied by loss of most physical cross-links. Higher energy photons permit, in part, photoinitiated retro-cycloaddition and a subsequent decrease in covalent cross-link density. It is thus possible to tailor the physical properties of the elastomer to increase and/or decrease the modulus of the elastomer using light and to conver... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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