In this study, Polyurea/Formaldehyde (PUF) microcapsules containing Dicyclopentadiene (DCPD) as a healing substance were fabricated in situ and mixed at relatively low concentrations (<2 wt%) with a thermosetting polyurethane (PU) foam used in turn as the core of a sandwich structure. The shape memory (SM) effect depended on the combination of the behavior of the PU foam core and the shape memory polymer composite (SMPC) laminate skins. SMPC laminates were manufactured by moulding commercial carbon fiber-reinforced (CFR) prepregs with a SM polymer interlayer. At first, PU foam samples, with and without microcapsules, were mechanically tested. After, PU foam was inserted into the SMPC sandwich structure. Damage tests were carried out by compression and bending to deform and break the PU foam cells, and then assess the structure self-healing (SH) and recovery capabilities. Both SM and SH responses were rapid and thermally activated (120 °C). The CFR-SMPC skins and the PU foam core enable the sandwich to exhibit excellent SM properties with a shape recovery ratio up to 99% (initial configuration recovery). Moreover, the integration of microcapsules (0.5 wt%) enables SH functionality with a structural restoration up to 98%. This simple process makes this sandwich structure ideal for different industrial applications.

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A shape memory polymer composite (SMPC) unit has been manufactured with embedded heater. The structure of the SMPC unit has been designed to allow reaching high recovery loads with a reduced size of the functional device. The unit is a composite sandwich with four carbon fibre reinforced (CFR) plies, two SMP foam cores, and one SMP interlayer. In the mid-plane of the sandwich the heater is integrated, being immersed in the SMP interlayer. The adopted manufacturing procedure was able to provide the necessary consolidation in one step moulding thanks to the use, during lamination, of pre-formed SMP cores, and uncured SMP powder for the interlayer. The SMP cores were manufactured by solid state foaming of the same SM epoxy powder. SMPC laminates, without the embedded heater, were also manufactured for testing as well as traditional four-ply CFR laminates. Several tests were carried out for temperature calibration and for investigating SM properties of the SMPC laminates and unit. Dynamic mechanical analyses, hot bending tests, and microscopic observations were performed on CFR and SMPC laminates. It was found that the SMP layers reduce the glass transition temperature of the laminates as well as the transition onset temperature and, above all, the extension of the transition range thus providing the trigger effect to the SMPC transition. Double-cycle SM tests were carried on the SMPC unit at different temperatures from 160 °C to 190 °C. The unit (20 × 45 mm2) was able to exert recovery loads over 7.4 N almost independently from the temperature and without any evidence of failure after several repeated tests. High values were measured also for the shape fixity and shape recovery which were, on average, higher than 96% and 95%, respectively.