Reinvestigation of thermal isomerization of cis-stereoregulated poly(phenylacetylene) by spectroscopic study and DFT calculation
نویسندگان
چکیده
Cis-stereoregulated poly(phenylacetylene) [poly(PA)] was synthesized by polymerization of PA using Rh catalysts, and the thermal isomerization behavior analyzed DSC, 1H NMR, IR Raman spectroscopies. Cis-poly(PA) exhibited DSC exothermic peaks around 170 °C corresponding to main chain from cis trans. The content decreased 12% after heating at °C, became almost zero 180 which determined NMR spectroscopy. Vibration frequencies 8-mer models cis- trans-poly(PA) were calculated DFT method simulate spectra. calculations indicated that an absorption peak 737 cm−1 poly(PA) originates out-of-plane bending vibrations C–H C–Ph bonded cis-main chain, a 692 deformation in phenyl moieties substituted with trans-main chain. These two used determine geometrical structures present study confirmed provide useful evidences for characterizing poly(PA).
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ژورنال
عنوان ژورنال: Polymer
سال: 2021
ISSN: ['1873-2291', '0032-3861']
DOI: https://doi.org/10.1016/j.polymer.2021.124013