Anthracene functionalized terpyridines - synthesis and properties.
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ABSTRACT:
SUBMITTER: Wehmeier F
PROVIDER: S-EPMC2900913 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:The photo-reversible [4?s+4?s] cycloaddition reaction of pendant anthracene moieties represents a convenient strategy to impart wavelength dependent properties into hydrogenated carboxylated nitrile butadiene rubber (HXNBR) networks. The present article provides the 1H NMR data on the reaction kinetics of the side chain functionalization of HXNBR. 2-(Anthracene-9-yl)oxirane with reactive epoxy groups is covalently attached to the polymer side chain of HXNBR via ring opening reaction between the epoxy and the carboxylic groups. Along with the identification, 1H NMR data on the quantification of the attached functional groups are shown in dependence on reaction time and concentration of 2-(anthracene-9-yl)oxirane. Changes in the modification yield are reflected in the mechanical properties and DMA data of photo-responsive elastomers are illustrated in dependence on the number of attached anthracene groups. DMA curves over repeated cycles of UV induced crosslinking (?>300 nm) and UV induced cleavage (?=254 nm) are further depicted, demonstrating the photo-reversibility of the thermo-mechanical properties. Interpretation and discussion of the data are provided in "Design and application of photo-reversible elastomer networks by using the [4?s+4?s] cycloaddition reaction of pendant anthracene groups" (Manhart et al., 2016) [1].
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