Re­cyc­ling & Re-Use Po­ten­tiale

Functionalization of carbon fiber reinforced plastic.

 

Betreuer:

  1. Betreuer:                  Prof. Dr. rer. nat. Wolfgang Bremser
  2. Betreuer:                  Prof. Dr. Rene Wilhelm
  3. Praxispartner:         N. N.
  4. Industriepartner:   N.N.

Motivation:

CFRPs are composite engineered materials consisting of carbon fibers (CFs) as reinforcements and an organic epoxy resin as a matrix, a combination that renders the materials extremely strong but also lightweight. These features, along with their unique electrical conductivity, thermal stability, good resistance to corrosion, and high rigidity, have led to CFRPs being widely used in various applications. So the extensive use of CFRP is now starting to produce serious waste disposal problems. therefore, the prospect of recycling CFRP composites without damaging the mechanical properties and dimensions of CFs is of great commercial interest.

Along with other reported mechanical, thermal and chemical procedures to recycle carbon fiber reinforced epoxy resin which generally require complicated processes, expensive facilities or toxic chemicals, we demonstrate a new recycling technology with the benefit of Graphene oxide in chemical reaction named Diels-Alder (DA) reaction that stand out as a promising strategy to fabricate self-healing conductive materials thanks to highly efficient, simple and repeatedly healed through only the application of heat. 

Aims:

The aim of this work is recycling of Carbon Fiber reinforced epoxy resin composite by the help of Diels-alder and Retro Diels-alder chemical reaction between Graphene oxide analogs coated on the surface of the carbon fiber and furan or maleimide analogs associated with epoxy resin. Thermally reversible Diels−Alder reactions have attracted particular attention probably because of the fact that these reactions can take place under mild conditions with high chemoselectivity. Graphene oxide analogs will be used to modify and functionalize the surface of the carbon fiber to make a better Diels alder reaction.

The zero-band gap electronic structure of graphene enables it to function as either the diene or the dienophile in the Diels alder reaction. Thermally reversible Diels alder reaction between Graphene and furan analogs or Graphene and maleimide analogs can pave the way to form and then cleavage the bond between carbon fiber and epoxy resin (Diels-Alder and Retro Diels- Alder reaction).

Methods/Materials:

Materials: Epoxy resin, Graphite flake, reduced graphene oxide, doped graphene oxide derivatives, maleimide analogs, Furan analogs, raw carbon fiber rope, release agent, organic solvents like toluene, DMF, …

This research needs supporting evidence from FTIR, Raman spectroscopy, TGA (Thermogravimetric Analysis), DSC (Differential Scanning Calorimetry) to distinguish Diels alder adduct. And then after applying external stimulus due to Retro Diels-alder reaction, Mechanical tests and microstructural analyses are used to assess the mechanical properties and microstructures of the recycled fibers and to reveal the influences of the different reaction conditions, like Tensile tests on CFs to evaluate the residual tensile strength of the recycled CFs, scanning electron microscopy tests to observe the surface characteristics of the recycled CFs, Atomic force microscopy tests to scan the micromorphology of the recycled CF surface.