Abstract
Bimodal molecular weight distributions of alternating copolymers of the type (Me2Si−R2Si−SiMe2) n , where R=hexyl and butyl, were obtained by polymerization of BrSiMe2−R2Si−Me2SiBr, using the Wurtz coupling method. Analysis of the samples by pyrolysis GC MS and solution29Si NMR indicated that some randomization occurred, due to cleavage of the original Si−Si bonds in the monomer. The extent of randomization was significantly greater in the high molecular weight fractions. Based on the nature of the rings from the py MGC/MS traces and the number on nonads found in the29Si spectra, two types of randomization processes have been proposed, involving backbiting followed by (1) ring expulsion or (2) redistribution.
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Menescal, R., West, R. & Blazsó, M. Synthesis and characterization of alternating silane copolymers: (Me2Si−R2Si−Me2Si) n . J Inorg Organomet Polym 5, 217–236 (1995). https://doi.org/10.1007/BF01057894
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DOI: https://doi.org/10.1007/BF01057894