•Thermolysis of carbon fibre reinforced epoxy resin in nitrogen–oxygen atmosphere.•Temperature, oxygen concentration and reaction time are important factors.•About 80% of tensile strength and modulus was preserved at optimum conditions.Pyrolysis is a common method for recycling carbon fibre reinforced polymer composites. However, carbonized residue is preferred to form on fibre surface. Thermal processing in air could eliminate the carbonized residue but the mechanical strength of the inherent fibre tends to be damaged by oxidation. Here, we investigated the influence of the temperature, oxygen concentration in nitrogen and time on the thermal decomposition of carbon fibre reinforced 4,4′-diaminodiphenylmethane cured epoxy resin composite and properties of the recycled carbon fibres. The properties of the recycled carbon fibre were characterized using single tensile test, SEM and XPS. Temperature, oxygen concentration and reaction time appear to be the important factors to tensile strength of the recovered carbon fibres. About 80% of tensile strength and modulus was preserved at optimum conditions. Gas and liquid products from DDM cured epoxy resin were also analysed in nitrogen and 5% O2–95% N2.

Recycling of carbon fiber reinforced epoxy resin composites has been investigated using molten potassium hydroxide as reaction media. The epoxy resin in composites was decomposed at temperatures ranged from 285 to 330 °C. The recovered carbon fibers were characterized by SEM, XPS and single fiber tensile test. More than 95% of the tensile strength of the virgin carbon fibers was retained. The surface C–OH decreased and COOH increased with increasing temperature. The decomposition products of epoxy resin in KOH was separated and analyzed by FTIR and MALDI-TOF. A possible mechanism for the decomposition of epoxy resin is proposed. The real-world CFRP wastes containing various contaminants such as thermoplastics, paints, sealants and glass fibers were also decomposed in the molten KOH.

•Silicon nitride nanoparticles were treated with GX-540 silane coupling agent.•High thermal stability was achieved through adding the reinforcing phase.•Addition of 15 wt% of nanoparticles enhanced the modulus by 2.3 GPa.•At 15 wt% nanofillers loading the Tg reached 360 °C.•SEM test highlighted the particles/matrix good adherence and affinity.A new kind of nanocomposites based on phthalonitrile resin reinforced with silicon nitride (SiN) nanoparticles was prepared by a hot compression molding technique. For different weight ratios ranging between 0% and 15%, the effect of nano-SiN particles on the thermal and thermomechanical properties has been studied. Results from thermal analysis revealed that the starting decomposition temperature and the residual weight at 800 °C were highly improved upon adding the reinforcing phase. At the maximum nano-SiN loading, dynamic mechanical analysis showed an enhancement in both storage modulus and glass transition temperature, reaching 4 GPa and 360 °C respectively. Scanning electron microscope analysis confirmed that these improvements are essentially attributed to the good dispersion and adhesion between the particles and the resin thanks to the particles treatment with silane coupling agent.

The porous carbon nanotubes were selectively prepared from the pristine carbon nanotubes. The surface of carbon nanotubes was firstly functionalized with Fe2O3 nanoparticles and subsequent heat treatment induced CNT etching. After removal of Fe2O3 nanoparticles, mesopores were formed in carbon nanotubes and thus porous structure was obtained. The obtained material of porous carbon nanotubes with higher specific surface area and larger pore sizes was tested as anode material of lithium ion batteries and showed improved performance with respect to the pristine carbon nanotubes.

A novel furan-containing tetrafunctional fluorene-based benzoxazine monomer with bisphenol- and diamine-type oxazine rings was successfully prepared. The resulting polybenzoxazine exhibits extremely higher glass transition temperature (440 °C) and better thermal stability than difunctional furan-containing fluorene-based and traditional multifunctional benzoxazine resins.

The porous carbon nanotubes were selectively prepared from the pristine carbon nanotubes. The surface of carbon nanotubes was firstly functionalized with Fe2O3 nanoparticles and subsequent heat treatment induced CNT etching. After removal of Fe2O3 nanoparticles, mesopores were formed in carbon nanotubes and thus porous structure was obtained. The obtained material of porous carbon nanotubes with higher specific surface area and larger pore sizes was tested as anode material of lithium ion batteries and showed improved performance with respect to the pristine carbon nanotubes.