An innovative recycling process for thermoset composite laminates is proposed by thermo-mechanical disassembly and further compression molding of hybrid thermoformable composite plates. Due to the thermo-mechanical process, single cured plies are extracted from the waste laminate. Subsequently re-lamination is performed by interposing thermoplastic films between the reclaimed composite plies. Final consolidation is carried out by compression molding. In order to show the feasibility of the novel recycling technology, carbon fiber reinforced composite plates by autoclave molding were thermo-mechanically disassembled in a manual roll bending machine after heating in oven. Reclaimed cured plies were laminated by alternating thermoplastic interlayers made of low density polyethylene. The hybrid laminate was consolidated at the temperature of 220�C and the holding pressure of 38.5 bar. Results from bending tests on virgin and recycled plates showed the very good agglomeration of the hybrid samples and the optimal preservation of performances of initial cured plies of the virgin material into the recycled plate.

Hybrid composite laminates are manufactured by using technologies and raw materials of the aeronautic sector with the aim to improve the damping behavior of composite structures. Matrix hybridization was achieved by laminating carbon fiber reinforced (CFR) plies with elastomer interlayers. Up to 10 different composite sandwich architectures were investigated by changing the stacking sequence, the thickness of the elastomer layers, and the elastomer typology, whereas the total number of the CFR plies was fixed to six for all the hybrid composites. Square panels with the size of 300 × 300 mm2 were autoclave molded with vacuum bagging, and rectangular samples were extracted for static and dynamic tests. Dynamic mechanical analyses were performed to measure the storage modulus and loss factor of hybrid materials, which were compared with static and dynamic performances of the composite structures under bending. Repeated loading–unloading cycles and free oscillation tests allowed us to the energy loss per unit of volume, and the acceleration damping, respectively. Results show that softest elastomer interlayers lead to big loss of stiffness without any positive effect in the damping behavior, which worsens as well. By using soft elastomers, complex architectures do not provide any additional benefit in comparison with the traditional sandwich structure with soft core and hard skins.

Carbon nanotubes (CNTs) are deposited between prepreg plies of a carbon fiber reinforced (CFR) laminate during lamination to improve laminate strength. An easy manufacturing procedure has been implemented for this aim in laboratory. CNTs are diluted in a solvent, and subsequently sprayed on commercial woven fabric prepregs for aeronautics. Solvent evacuation is carried out at room temperature. Final composite laminates are produced by vacuum bagging and autoclave molding of coated prepreg plies, by following the typical industrial procedure of aeronautic parts. Quasi-isotropic square laminates with 10 plies have been manufactured by using a unidirectional (UD) CFR prepreg tape with 0/90 stacking sequence. After molding, the square laminates (150 × 150 mm2) were cut to extract rectangular specimens. Mechanical tests were made by bending up to break. Results confirm the positive role of the interlaminar CNTs if they are correctly integrated into the final composite structure.

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