Preparation and characterization of 4D printable PCL/SEBS‐g‐MAH blends with excellent mechanical and shape memory properties

This work focuses on developing a novel thermal‐responsive shape memory Poly(ε‐caprolactone) (PCL)/maleic‐anhydride grafted poly[styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene] (SEBS‐g‐MAH) blends, with enhanced shape memory and mechanical properties, which is tailored for 3D printing applications. The thermal, mechanical, and rheological properties of the blends were rigorously assessed by DSC, TGA, mechanical testing, and dynamic rheological analysis. The results show that the elongation at the break of the blends exceeds 1000%, which can be attributed to the formation of the co‐continuous structure. Thermal‐responsive shape memory properties characterized by the water bath circulation method showed that the PCL4/MAH6 exhibited the optimal overall performance (shape fixation rate of 97.22%, shape recovery rate of 96.67%) and remained stable after 10 cycles of testing. Moreover, the effect of printing parameters on shape memory properties was investigated, revealing that blends perform the most promising memory behavior at a layer thickness of 0.1 mm, hot‐bed temperature of 40°C, and printing speed of 40 mm/s. In addition, the relationship between the composition of the blends and their properties was investigated at the molecular level by molecular dynamics simulations, which were in agreement with the experimental observations. In conclusion, this study provides new perspectives on the development of advanced materials suitable for 4D printing applications.Highlights The co‐continuous structure effectively enhances blends' mechanical properties. The storage modulus exerts a dominant influence on the shape memory properties. Molecular dynamics simulations are employed to validate experimental observations.