A special honor has been bestowed upon researchers from the WACKER Group and from the WACKER Institute for Silicon Chemistry at the Technical University of Munich, Germany. Their pioneering work on eliminating the need for precious metals in crosslinking silicone rubber was published by the Royal Society of Chemistry (RSC) in its volume “2020 Green Chemistry” which honors outstanding contributions to the development of sustainable concepts for the chemical industry. Headquartered in London, the society is one of the oldest and most prestigious professional associa- tions for chemists. The organization’s publications, for instance, have been advancing scientific work for over 175 years.
A team of researchers led by Professor Bernhard Rieger, who holds the WACKER Chair of Macromolecular Chemistry at the Technical University of Munich, and Dr. Richard Weidner, who oversees organosilicon research at the Consortium für elektrochemische Industrie, the central R&D department of the WACKER Group, has now found a promising way of curing silicone rubber without the use of precious-metal catalysts. Rather than working with otherwise standard crosslinkers, the scientists instead used silicone building blocks containing silirane units.
The team successfully showed that their method can be used for crosslinking silicone rubber. The final properties are determined exclusively by the selection of starting products and their mixing ratio. The silicone elastomers produced in this way are characterized by their exceptional purity, containing neither volatile substances nor traces of precious metals. “That’s especially true for elastomers, which are crosslinked via a ring-opening reaction. Silicones like these are particularly suitable for medical applications or as encapsulants for the electronics industry,” says Bernhard Rieger.
What makes this a trailblazing paper is that, for the first time, it shows, in principle, a way of making such highly reactive silicon compounds useful for industrial application. Researchers have to overcome a few more hurdles, however, to demonstrate practical viability for industrial use.