Chapter 85. New Organofunctional Silanes for Adhesives, Sealants and Spray Foams
- Prof. Dr. Norbert Auner2 and
- Prof. Dr. Johann Weis3
Published Online: 5 MAY 2008
Copyright © 2003 WILEY-VCH Verlag GmbH & Co. KgaA
Organosilicon Chemistry V: From Molecules to Materials
How to Cite
Bauer, A., Kammel, T., Pachaly, B., Schäfer, O., Schindler, W., Stanjek, V. and Weis, J. (2003) New Organofunctional Silanes for Adhesives, Sealants and Spray Foams, in Organosilicon Chemistry V: From Molecules to Materials (eds N. Auner and J. Weis), Wiley-VCH Verlag GmbH, Weinheim, Germany. doi: 10.1002/9783527619924.ch85
Department of Inorganic Chemistry, University of Frankfurt, Marie-Curie-Straße 11, 60439 Frankfurt am Main, Germany
Consortium of Electrochemical Industry GmbH, Zielstattstraße 20, 81379 Munich, Germany
- Published Online: 5 MAY 2008
- Published Print: 26 SEP 2003
Print ISBN: 9783527306701
Online ISBN: 9783527619924
- spray foam;
Besides the well-known application of silanes as adhesion promoters and surface modifiers, organofunctional silanes have also long been applied as terminating agents in organic polymers. The silane condensation in such polymer systems is currently replacing other curing chemistry, such as the use of isocyanates in polyurethanes. For example, silyl-endcapped polyethers and polyurethanes have been developed and their application potentials in sealants, adhesives and coatings have been verified.
This work gives a survey of a new class of α-organofunctional alkoxysilanes and their potential use. These silanes exhibit dramatically enhanced reactivities. Through variation of the organofunctional group (e.g. isocyanato, amino) access to numerous applications is possible.
With isocyanatomethyl alkoxysilanes (α-NCO-silanes) as endcappers, polymers with enhanced properties are feasible. This concept involving α-NCO-silanes is not limited to distinct polymer types and therefore has a broad application base. Additionally, highly reactive ethoxy-functional crosslinking systems are now available. These polymers show low viscosity and consequently a higher formulation flexibility.
An intriguing new application of α-aminosilanes are silane crosslinking spray foams. These foams do not contain any isocyanates which are critical to toxicological and enviromental implications. Due to their high reactivities, α-silanes exhibit excellent curing characteristics. Moreover they provide good mechanical properties and are produced from only low-cost compounds.