TU Darmstadt / ULB / TUbiblio

Viscoelastic properties of novel silicon carbodiimide gels

Balan, C. and Völger, K.-W. and Kroke, E. and Riedel, R. (2000):
Viscoelastic properties of novel silicon carbodiimide gels.
In: Macromolecules, 33 (9), ACS, pp. 3404-3408, [Article]

Abstract

A novel non-oxide sol-gel system based on the reaction of bis(trimethylsilyl)carbodiimide with methyltrichlorosilanes has been examined quantitatively with regard to its viscoelastic properties. The chemistry and phenomenology of this process are completely analogous to the well-known oxide solgel process. The changes of the elastic modulus G¢ and the viscous modulus G¢¢ have been measured with low strain amplitude and constant frequency versus time. At the crossover point, i.e., G¢ ) G¢¢, the gel point is reached. The gelation time is independent of the oscillatory frequency ˆ. The dynamic moduli G¢ and G¢¢ have also been measured versus strain amplitude and shear stress amplitude. A relaxation exponent of n ) 0.65, strength S ) 0.25, and G¢(end of reaction) ) 105 Pa‚s have been determined.

Item Type: Article
Erschienen: 2000
Creators: Balan, C. and Völger, K.-W. and Kroke, E. and Riedel, R.
Title: Viscoelastic properties of novel silicon carbodiimide gels
Language: English
Abstract:

A novel non-oxide sol-gel system based on the reaction of bis(trimethylsilyl)carbodiimide with methyltrichlorosilanes has been examined quantitatively with regard to its viscoelastic properties. The chemistry and phenomenology of this process are completely analogous to the well-known oxide solgel process. The changes of the elastic modulus G¢ and the viscous modulus G¢¢ have been measured with low strain amplitude and constant frequency versus time. At the crossover point, i.e., G¢ ) G¢¢, the gel point is reached. The gelation time is independent of the oscillatory frequency ˆ. The dynamic moduli G¢ and G¢¢ have also been measured versus strain amplitude and shear stress amplitude. A relaxation exponent of n ) 0.65, strength S ) 0.25, and G¢(end of reaction) ) 105 Pa‚s have been determined.

Journal or Publication Title: Macromolecules
Volume: 33
Number: 9
Publisher: ACS
Divisions: 11 Department of Materials and Earth Sciences
11 Department of Materials and Earth Sciences > Material Science
11 Department of Materials and Earth Sciences > Material Science > Dispersive Solids
Date Deposited: 19 Nov 2008 16:24
Funders: Financial support by the Deutsche Forschungsgemeinschaft and the Fonds der Chemischen Industrie is gratefully acknowledged., For offering a research fellowship to Prof. Corneliu Balan acknowledges the financial support of DAAD, Bonn.
Export:
Suche nach Titel in: TUfind oder in Google
Send an inquiry Send an inquiry

Options (only for editors)

View Item View Item