Carbon Fiber meets Polypropylene: New Opportunities with CF/Thermoplastic Composites

Thermoplastic matrices for composite solutions are becoming increasingly popular in various markets like automotive, aerospace, oil & gas but also in consumer and sports. Thermoplastic composites materials with carbon fibres (CFRTP) based on polar matrices like PA6 have been well developed, whereas non-polar polyolefin based CFRTP (e.g. with PP matrix) still have issues on interfacial surface between carbon fibre and polyolefin matrices, resulting in low durability and low mechanical properties.

However, CFRTP based on PP have a huge potential to contribute to manufacture an economical, high performance lightweight composite as CF-PP could offer lower densities and higher rigidity combined with a high weight reduction, higher workability for further processing steps as well as outstanding resistance to water absorption and hydrolysis.

With regards to the mentioned challenge of this material combination, a recent composite development of Mitsui Chemicals is focusing on unidirectional tapes based on carbon fibre and polypropylene (TAFNEXâ„¢ CF-PP UD).

Therefore, the first part of the presentation will describe the process and material development in which a special PP-compatible bonding solution for carbon fibers has been new-developed for improved fiber matrix adhesion resulting in higher mechanical properties. In addition, an own modified PP compound as matrix is used, so that the
bonding is further increased and higher application temperatures are possible for a short time.

In the second part of the presentation developments will be presented where TAFNEXâ„¢ CF-PP UD has been used in hybrid solutions (e.g. with injection moulding compounds or GF-based organosheets) to enable a cost-effective solution for semi-structural applications. A simulation approach has been developed together with our subsidiary ARRK Engineering using TAFNEXâ„¢ CF-PP UD to predict the crash behaviour and improve the lay-up of the UD tapes in the part.