| Autor: |
Nosiglia MA; Department of Chemistry, Washington University, St. Louis, Missouri 63130, United States., Colley ND; Department of Chemistry, Washington University, St. Louis, Missouri 63130, United States., Danielson MK; Department of Chemistry, Washington University, St. Louis, Missouri 63130, United States., Palmquist MS; Department of Chemistry, Washington University, St. Louis, Missouri 63130, United States., Delawder AO; Department of Chemistry, Washington University, St. Louis, Missouri 63130, United States., Tran SL; Department of Chemistry, Washington University, St. Louis, Missouri 63130, United States., Harlan GH; Department of Chemistry, Washington University, St. Louis, Missouri 63130, United States., Barnes JC; Department of Chemistry, Washington University, St. Louis, Missouri 63130, United States. |
| Abstrakt: |
Mechanically interlocked molecules (MIMs) possess unique architectures and nontraditional degrees of freedom that arise from well-defined topologies that are achieved through precise mechanical bonding. Incorporation of MIMs into materials can thus provide an avenue to discover new and emergent macroscale properties. Here, the synthesis of a phenanthroline-based [2]catenane crosslinker and its incorporation into polyacrylate organogels are described. Specifically, Cu(I) metalation and demetalation was used as a postgelation strategy to tune the mechanical properties of a gel by controlling the conformational motions of integrated MIMs. The organogels were prepared via thermally initiated free radical polymerization, and Cu(I) metal was added in MeOH to the pretreated, swollen gels. Demetalation of the gels was achieved by adding lithium cyanide and washing the gels. Changes in Young's and shear moduli, as well as tensile strength, were quantified through oscillatory shear rheology and tensile testing. The reported approach provides a general method for postgelation tuning of mechanical properties using metals and well-defined catenane topologies as part of a gel network architecture. |
