Institute for Applied Materials – Materials Science and Engineering

Polymer-based functional composites

In microsystems technology, in addition to silicon, plastics (polymers), metals and ceramics are well established as materials for components and products. For the realization and cost-effective production of microtechnical products, suitable materials have to meet the following general criteria:

  • good availability
  • reproducible material quality
  • acceptable price
  • good microstructurability
  • simple processability and handling

In addition, the individual physical properties that define the application purpose and area of application must be taken into consideration. Only in very few cases are all criteria fulfilled at once, so when designing and dimensioning a microtechnical component, compromises must be made either in the desired physical properties or in the processability. The use of commercially available materials rarely allows the simultaneous optimal adjustment of several physical properties such as thermal expansion, electrical conductivity or optical refractive index, so that the realization of complex property profiles often requires the development of special materialsThe use of composites is one solution to this problem. These consist of at least two different components, which are physically separated in a material composite. If the single components are chosen cleverly, a combination of the most favourable individual properties is possible, so that a tailoring of physical composite properties can be realised within certain limits.
Especially the use of nanoscale inorganic and organic filling and doping materials allows the tailoring of the physical properties of polymer-based functional composites. At the moment, the research work focuses on the following property changes:

  • Fluidity
  • Optical properties (refractive index, transmission, fluorescence in Vis and NIR range)
  • Dielectric properties (permittivity and dielectric loss)
  • Electrical properties
  • Thermomechanical properties (thermal expansion coefficient, hardness, softening temperature)

In addition to the focused property modification, the necessary process technologies for the realization of simple demonstrator components are developed. These include:

  • Light and thermally induced polymerization of the polymer matrix
  • Chemical modification of the particle-matrix interface
  • Dispersing technology
  • Design

 

For any further questions on this topic please contact Mr. Dr. Steffen Antusch