This study considers a fabrication of magnetoactive scaffolds based on a copolymer of vinylidene fluoride and trifluoroethylene (P(VDF-TrFE)) and 5, 10, and 15 wt.% of magnetite (Fe₃O₄) nanoparticles modified with citric (CA) and oleic (OA) acids by solution electrospinning. The synthesized Fe₃O₄-CA and Fe₃O₄-OA nanoparticles are similar in particle size and phase composition, but differ in zeta potential values and magnetic properties. Pure P(VDF-TrFE) scaffolds as well as composites with Fe₃O₄-CA and Fe₃O₄-OA nanoparticles demonstrate beads-free 1 μm fibers. According to scanning electron (SEM) and transmission electron (TEM) microscopy, fabricated P(VDF-TrFE) scaffolds filled with CA-modified Fe₃O₄ nanoparticles have a more homogeneous distribution of magnetic filler due to both the high stabilization ability of CA molecules and the affinity of Fe₃O₄-CA nanoparticles to the solvent used and P(VDF-TrFE) functional groups. The phase composition of pure and composite scaffolds includes a predominant piezoelectric β-phase, and a γ-phase, to a lesser extent. When adding Fe₃O₄-CA and Fe₃O₄-OA nanoparticles, there was no significant decrease in the degree of crystallinity of the P(VDF-TrFE), which, on the contrary, increased up to 76% in the case of composite scaffolds loaded with 15 wt.% of the magnetic fillers. Magnetic properties, mainly saturation magnetization (M_s), are in a good agreement with the content of Fe₃O₄ nanoparticles and show, among the known magnetoactive PVDF or P(VDF-TrFE) scaffolds, the highest M_s value, equal to 10.0 emu/g in the case of P(VDF-TrFE) composite with 15 wt.% of Fe₃O₄-CA nanoparticles.

Shape-memory polymers (SMPs) are a class of smart materials capable of recovering their original shape from a programmed temporary shape in response to external stimuli such as heat, light, or magnetic fields. SMPs have attracted significant interest for biomedical devices and soft robotics due to their large recoverable strains, programmable mechanical and thermal properties, tunable activation temperatures, responsiveness to various stimuli, low density, and ease of processing via additive manufacturing techniques, as well as demonstrated biocompatibility and potential bioresorbability. This review summarises recent progress in the fundamentals, classification, activation mechanisms, and fabrication strategies of SMPs, focusing particularly on design principles that influence performance relevant to specific applications. Both thermally and non-thermally activated SMP systems are discussed, alongside methods for controlling activation temperatures, including plasticisation, copolymerisation, and modulation of cross-linking density. The use of functional nanofillers to enhance thermal and electrical conductivity, mechanical strength, and actuation efficiency is also considered. Current manufacturing techniques are critically evaluated in terms of resolution, material compatibility, scalability, and integration potential. Biodegradable SMPs are highlighted, with discussion of degradation behaviour, biocompatibility, and demonstrations in devices such as haemostatic foams, embolic implants, and bone scaffolds. However, despite their promising potential, the widespread application of SMPs faces several challenges, including non-uniform activation, the need to balance mechanical strength with shape recovery, and limited standardisation. Addressing these issues is critical for advancing SMPs from laboratory research to clinical and industrial applications.

Biocompatible poly(lactic acid) (PLA) was plasticized with poly(ethylene glycol) (PEG) added at concentrations of 10, 15, and 20 wt.% relative to PLA, and then processed into gyroid triply periodic minimal surface (TPMS) scaffolds using fused filament fabrication (FFF) 3D printing. The influence of PEG concentration and gyroid structure (50% infill density) on thermal transitions, crystallinity, and low–temperature shape-memory performance was systematically investigated. The shape-memory effect (SME) of the PLA–based scaffolds was tailored through compositional control and structural design. Shape recovery under thermal activation at 40 °C and 50 °C was examined to reveal the correlation between composition and structure in governing low–temperature shape-memory behavior. The optimal composition (PLA/10 PEG, 50% gyroid infill) achieved shape recovery with a recovery ratio (R_r) of 97 ± 1% at 40 °C within 6 ± 1 min, demonstrating optimal shape-memory activation close to physiological temperature. Structural and morphological changes were characterized using ATR–FTIR, Raman spectroscopy, DSC, XRD, and SEM, providing comprehensive insight into the plasticization of the PLA matrix and its impact on structure–property relationships relevant to bone tissue engineering.