Abstract
Various hydrolysates of trichlorophenylsilane (TCP) and their polycondensates were reacted with trichlorosilane for capping the silanol groups formed in defect points of the ladder structure. The 1H NMR spectra of the capping products obtained showed several signals due to the Me3Si groups in different environment. Particularly, the polycondensate prepared from the TCP hydrolysate having higher molecular weight showed both sharp and broad Me3Si signals, suggesting a core-shell type branched structure. No Me3Si signal was shown in the polycondensate prepared from the hydrolysate with low molecular weight, supporting an almost perfect ladder structure with few bonding defects. The wide angle X-ray scattering (WAXS) of this polycondensate showed clear Debye-Scherrer rings due to the crystallization of the polymer chains having the regular ladder structure. The structural regularity of this polycondensate was also supported by the 29Si NMR spectrum. This polymer, having a stable double-strand structure, was found to undergo no base-catalyzed depolymerization in solution. A stepwise polycondensation is proposed for the formation of the ladder polymer in which the trivalent (T0: PhSi(O−)3) or divalent (T1: PhSi(OSi)(O−)2) siloxyl units should be involved in the reaction, leaving the monovalent siloxyl (T2: PhSi(OSi)2(O−)) units unreacted.
Similar content being viewed by others
Article PDF
References
A. Ladenburg, Ber., 6, 379 (1873).
Meads and F. S. Kipping, J. Chem. Soc., 105, (1914).
K. Larsson, Arkiv Kemi, 16, 209 (1960).
K. Larsson and C. Grunwall, Arkiv Kemi., 17, 529 (1961).
J. F. Brown, Jr., L. H. Vogt, Jr., and P. I. Prescott, J. Am. Chem. Soc., 86, 1120 (1963).
J. F. Brown, J. Polym. Sci., Part C., 1, 83 (1963).
J. F. Brown, Jr. and L. H. Vogt, J. Am. Chem. Soc., 87, 4313 (1965).
M. M. Sprung and F. O. Guenther, J. Polym. Sci., 28, 17 (1958).
J. S. Hrkach and K. Matyjaszewski, J. Polym. Sci., A: Polym. Chem., 33, 285 (1995).
K. J. Mcneil, J. A. Dicaprio, D. A. Walsh, and R. F. Pratt, J. Am. Chem. Soc., 102, 1859 (1980).
T. Takiguchi, R. Fujikawa, Y. Yamamoto, and M. Ueda, Nippon Kagaku Kaishi, 108 (1974).
E. C. Lee and Y. Kimura, Polym. J., 29, 678 (1997).
H. Nishida, H. Yamane, Y. Kimura, and T. Kitao, Kobunshi Ronbunshu, 53, 193 (1996).
H. Ban, A. Tanaka, Y. Kawai, and S. Imamura, Polymer, 31, 564 (1990).
M. Smaihi, T. Jermoumi, and J. Marignan, Chem. Mater., 7, 2298 (1995).
P. Xie, Y. Wan, B. Zhou, J. Hou, D. Dai, Z. Li, D. Liu, and R. Zhang, Macromol. Chem. Phys., 197, 745 (1996).
T. Takiguchi, J. Am. Chem. Soc., 81, 2359 (1959).
B. L. Tyler, J. Am. Chem. Soc., 77, 770 (1955).
K. A. Andrianov, G. L. Slonimsky, A. A. Zhdanov, D. Ya. Tsvankin, V. Yu. Levin, V. S. Papkov, Yu. P. Kvachev, and E. M. Belavtseva, J. Polym. Sci., 14, 1205 (1976).
M. Konda, E. C. Lee, and Y. Kimura, unpublished data.
We have reported 59.6 MHz 29Si NMR spectra of the TCP hydrolysates having different molecular weight. Here we reinvestigated the same spectra at a higher frequency of 99.3 MHz by using a pure TMS in a cappilary tube as the in situ external reference. The chemical shift of the signals was found to be significantly different from the former value by δ−7.5 ppm which had been measured with the signal of a sample of TMS in chloroform-d1 as the machinary 0 ppm (see ref 12).
J. Chojnowski, Spec. Publ. R. Soc. Chem., 166, 59 (1995).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Lee, EC., Kimura, Y. Structural Regularity of Poly(phenylsilsesquioxane) Prepared from the Low Molecular Weight Hydrolysates of Trichlorophenylsilane. Polym J 30, 234–242 (1998). https://doi.org/10.1295/polymj.30.234
Issue Date:
DOI: https://doi.org/10.1295/polymj.30.234