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Timothy R. Totsch Victoria L. Stanford Oleksander Klep Mary K. Burdette Benjamin Grant Stephen H. Foulger Gary M. Gray 《Journal of polymer science. Part A, Polymer chemistry》2020,58(13):1825-1842
Linear polyphosphonates with the generic formula –[P(Ph)(X)OR′O]n– (X = S or Se) have been synthesized by polycondensations of P(Ph)(NEt2)2 and a diol (HOR′OH = 1,4-cyclohexanedimethanol, 1,4-benzenedimethanol, tetraethylene glycol, or 1,12-dodecanediol) followed by reaction with a chalcogen. Random copolymers have been synthesized by polycondensations of P(Ph)(NEt2)2 and mixture of two of the diols in a 2:1:1 mol ratio followed by reaction with a chalcogen. Block copolymers with the generic formula –[P(Ph)(X)OR′O](x + 2) –[P(Ph)(X)OR′O](x + 3)– (X = S or Se) have been synthesized by the polycondensations of Et2N[P(Ph)(X)OR′O](x + 2)P(Ph)NEt2 oligomers with HOR′O[P(Ph)(X)OR′O](x + 3)H oligomers followed by reaction with a chalcogen. The Et2N[P(Ph)(X)OR′O](x + 2)P(Ph)NEt2 oligomers are prepared by the reaction of an excess of P(Ph)(NEt2)2 with a diol while the HOR′O[P(Ph)(X)OR′O](x + 3)H oligomers are prepared by the reaction of P(Ph)(NEt2)2 with an excess of the diol. In each case the excess, x is the same and determines the average block sizes. All of the polymers were characterized using 1H, 13C{1H}, and 31P{1H} NMR spectroscopy, TGA, DSC, and SEC. 31P{1H} NMR spectroscopy demonstrates that the random and block copolymers have the expected arrangements of monomers and, in the case of block copolymers, verifies the block sizes. All polymers are thermally stable up to ~300°C, and the arrangements of monomers in the copolymers (block vs. random) affect their degradation temperatures and Tg profiles. The polymers have weight average MWs of up to 3.8 × 104 Da. 相似文献
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Jason L. Freeman Justin R. Martin T. Ross Totsch Farid Marashi Nia Jianwei Wang Yuanli Zhang Benjamin Yancey Jeffrey L. Atkinson Christopher M. Lawson Gary M. Gray 《Journal of polymer science. Part A, Polymer chemistry》2016,54(22):3663-3674
The syntheses of a series of substituted polyphosphonates of the type [OP(X)(Ar)O(CH2)12]n (X = O, S, Se; Ar = phenyl, 2,2′‐bithienyl‐5‐yl) are reported. The s for the polyphosphonates range from 1.1 to 4.6 × 104 Da and are significantly higher than those previously reported for polyphosphonates synthesized via polycondensation reactions. Thermal characterization indicates that all of the polymers are in the rubbery state at room temperature and have thermal stabilities as high as 290 °C. The linear absorption spectra, emission spectra, and emission quantum yields of the 2,2′‐bithenyl‐5‐yl substituted polyphosphonates show distinct trends with respect to the chalcogen attached to the phosphorus. Solutions of these polymers show emission at wavelengths ranging from 380 to 400 nm and, depending on the choice of X, the quantum yields are considerably larger than that of 2,2′‐bithiophene. Nonlinear optical measurements of the polyphosphonates with 2,2′‐bithenyl‐5‐yl substituents show that nonlinear absorbance increases with increasing molecular weight of X. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 3663–3674 相似文献
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