- Effect of spacer chemistry on the formation and properties of linear reversible polymers
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A series of four pairs of bismaleimide and bisfuran monomers were combined to make thermally reversible linear polymers. The monomers were prepared using diamines having different spacer chemistries, n-octyl, cyclohexyl, phenyl, and ethylenedioxy, such that a relatively constant spacer dimension among the four monomers was achieved. Heating of the bismaleimide/bisfuran couples resulted in low-viscosity, easily processable liquids. Subsequent cooling to room temperature resulted in the formation of hard films, with the rate of hardening varying significantly within the series of compounds. The rate and degree of polymerization were determined using 1H NMR spectroscopy and were both found to be dependent on the chemistry of the spacer group, as was the film rheology, which was measured using nanoindentation. Adhesion of the polymers was quantified by measurement of their tensile adhesive strength, and this was also found to be spacer dependent. Polymerization reversibility was verified using 1H NMR spectroscopy. Copyright
- Mayo, James D.,Adronov, Alex
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- Reversible polymer composition
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A composition includes a reversible polymer material, which can reversibly transition between a liquid state and a solid state by reversible cycloaddition reactions, wherein upon cooling, the reversible polymer material transitions from a liquid state to a solid state by reversible cycloaddition reactions within a time period of less than about 10 seconds.
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Page/Page column 10; 11
(2015/02/25)
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- A two-directional strategy for the diversity-oriented synthesis of macrocyclic scaffolds
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Macrocyclic compounds represent a structural class with exceptional potential for biological activity; however, they have historically been underrepresented in screening collections and synthetic libraries. In this article we report the development of a highly step-efficient strategy for the diversity-oriented synthesis of complex macrocyclic architectures, using a modular approach based on the two-directional synthesis of bifunctional linear precursors and their subsequent combination in a two-directional macrocyclisation process. In this proof of principle study, the synthesis of 14 such compounds was achieved. Cheminformatic analysis of the compounds produced suggests that they reside in biologically relevant regions of chemical space and the compounds were screened for activity against two cancer cell lines.
- O'Connell, Kieron M. G.,Beckmann, Henning S. G.,Laraia, Luca,Horsley, Helen T.,Bender, Andreas,Venkitaraman, Ashok R.,Spring, David R.
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supporting information
p. 7545 - 7551
(2012/10/29)
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