Nematic polymers: hairpins, ringlets and excimer fluorescence
نویسندگان
چکیده
Short liquid crystalline polymers in a nematic environment are very unlikely to cyclise. Hairpins, abrupt chain folds, favour cyclisation. As a result the cyclisation rate constant exhibits a maximum as a function of chain length. The maximum corresponds to a new object, a "ringlet". The rate constant also depends exponentially on temperature. This suggests excimer fluorescence as a probe of configurations and dynamics of main-chain liquid crystalline polymers.
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تاریخ انتشار 2016