- Special Diels-Alder reaction as chemical switch
- Processability of thermoplastics combined with mechanical properties of thermosetting polymers
- First potential customers have already received samples
Composites are a key technology for lightweight design because of their ability to combine very good mechanical properties and low weight. Their processing properties are mainly determined by the polymer. Thermosetting plastics have very good mechanical properties but do require longer processing times compared to thermoplastic materials. But then again, thermoplastic polymers are easy to process, quick to reshape and to recycle, however, they rarely demonstrate the excellent mechanical properties of thermosetting plastics.
There is a reason for the very different properties: polymer chains in thermosetting plastics are crosslinked whereas in thermoplastics they are not. Switching between crosslink and no link is usually not possible because a chemical crosslinking process is irreversible.
Special Diels-Alder reaction as chemical switch
However, this is exactly what Evonik achieved in cooperation with the Karlsruhe Institute of Technology in producing hybrid polymer systems. They are able to crosslink without using catalysts in a completely reversible process. Heating causes de-crosslinking and allows the system to be reshaped. During the cooling phase, the crosslink is created again and its shape becomes stabile.
A special Diels-Alder reaction causes this phenomenon where the crosslink is almost chemically switched on and off. Material properties are maintained even with repeated heating and cooling.
First potential customers have already received samples
Since late 2014, Evonik demonstrates in pilot plants at its Marl site that the material concept of hybrid polymer systems can save time and costs in manufacturing composites. First potential customers have already received samples for testing. First hybrid polymer systems are expected to be ready for the market in 2018.
Sales in triple-digit million € range aimed
The company is aiming for sales in the lower triple-digit million € range in the composites market in the medium term. For the market of carbon fiber-reinforced plastics alone, CCeV, a network of companies and research institutes in the fiber composites field, is expecting stabile annual growth of an average of 9 percent by 2020.