Silicone rubbers play an important role in medical technology as well as in the automotive and electrical industries due to their special physical and chemical properties and physiological harmlessness. In order to increase cost and energy efficiency compared to conventional processes, the SKZ Plastics Center is working with industrial partners to research innovative, continuous compounding processes.
Polymer dosing system "roll-ex® PDSE" from UTH GmbH. (Photo: UTH GmbH)
Continuous compounding processes for the production of solid silicone rubbers have advantages over the discontinuous processes currently used, such as superior process control, better mixing properties and generally high quality consistency. In addition, continuous processes have lower energy requirements and therefore contribute to CO2 savings. Another attractive factor is the associated cost savings. Despite the numerous advantages, continuous compounding processes are rarely used industrially for solid silicone rubber due to the challenging dosing and complex process control.
Continuous dosing in block form
The SKZ is tackling these challenges together with partners from industry in the "SiliComp" research project. As part of the research project, a process configuration is being developed with which solid silicone rubber can be continuously dosed in block form and compounded using twin-screw extruders and planetary roller extruders. For this purpose, the SKZ will first develop suitable model formulations that are adapted to the requirements of the industry. A dosing system from UTH GmbH will be used to develop the process setup. The process is designed for both twin-screw extruders and planetary roller extruders. The developed model formulations are compounded using the designed process configurations and the resulting mixtures are characterized. This is followed by ensuring transferability to industrial scale, for which ENTEX Rust & Mitschke GmbH provides its in-house technical center.
Project support committee
The results of the project are shared in a broad-based project support committee from all areas of the plastics and silicone industry. The first committee meeting will take place on June 24, 2024 at the SKZ in Würzburg. If companies are interested in participating, they can contact the project managers at any time. The results will also be made publicly available.
More about the materials development research area