High-yield controlled syntheses of polysilanes by the Wurtz-type reductive coupling reaction

Jones, R.G. and Holder, S.J. (2006) High-yield controlled syntheses of polysilanes by the Wurtz-type reductive coupling reaction. Polymer International, 55 (7). pp. 711-718. ISSN 0959-8103. (The full text of this publication is not available from this repository)

The full text of this publication is not available from this repository. (Contact us about this Publication)
Official URL
http://dx.doi.org/10.1002/pi.1945

Abstract

The factors that determine the Wurtz-type reductive coupling of dichloroorganosilanes by alkali metals are reviewed. A strong recommendation is advanced for carrying out all such polysilane syntheses in tetrahydrofuran at ambient temperature, conditions under which the reaction gives far higher yields and generally much narrower product molecular weight distributions. The higher yields are attributed to the ability of the solvent to sequester the sodium ion and thereby stabilize the anionic chain carriers. The bimodal molecular weight distributions of the product polymers, which are ubiquitous when such reactions are carried out in high-boiling-point aromatic solvents under reflux, as is common practice, are attributed to it being a defect-diffusion-controlled polymerization at the alkali metal surface. The narrower molecular weight distributions that result from syntheses in tetrahydrofuran are attributed to the suppression of defect diffusion rates at lower temperatures.

Item Type: Article
Additional information: 34 JOHN WILEY & SONS LTD
Uncontrolled keywords: polysilanes; Wurtz-type reaction; synthesis; mechanism; high yield; diffusion-control HIGH POLYMERS; BLOCK-COPOLYMERS; POLYMERIZATION; TEMPERATURE; POLY(METHYLPHENYLSILYLENE); DICHLOROSILANES; CONFORMATIONS; DISTRIBUTIONS
Subjects: Q Science > QD Chemistry
Divisions: Faculties > Science Technology and Medical Studies > School of Physical Sciences > Functional Materials Group
Faculties > Science Technology and Medical Studies > School of Physical Sciences
Depositing User: Simon Holder
Date Deposited: 29 Aug 2008 15:04
Last Modified: 14 Jan 2010 14:07
Resource URI: http://kar.kent.ac.uk/id/eprint/2555 (The current URI for this page, for reference purposes)
  • Depositors only (login required):