Hydrogenation of low‐molar‐mass,OH‐telechelic polybutadienes. II. Nuclear magnetic resonance and infrared spectrometric determination of hydroxyl end groups before and after hydrogenation by diimide |
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Authors: | J. Podeš va,J. Spě vá č ek,J. Dybal |
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Abstract: | 1H nuclear magnetic resonance (1H‐NMR), 13C‐NMR, and infrared spectroscopies were used to determine concentrations (cOH, in mmol/g) of the secondary hydroxyl end groups in the low‐molar‐mass, OH‐telechelic polybutadienes, and their hydrogenated analogs. Mean OH‐functionality (fOH ≤ 2), that is, an average number of OH groups per one polymer chain, was calculated from cOH for each sample and each method, and the results were compared with those obtained by a conventional acetic anhydride titration method. It has been found that with molar masses of the samples studied (2310 to 3410 g/mol), the differences between individual spectrometric methods are usually not higher than approximately 10%, which corresponds to an expected relative experimental error. Certain differences in fOH between individual methods are discussed. No systematic change of fOH after virtually total hydrogenation of the olefinic double bonds of the polymeric substrate by diimide was observed. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 3214–3224, 1999 |
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Keywords: | telechelic polybutadienes hydroxyl end groups 1H nuclear magnetic resonance spectroscopy 13C nuclear magnetic resonance spectroscopy infrared spectroscopy |
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