Characterization and Preparation of Thermo‐Responsive Shape Memory <scp>PETG</scp>/<scp>POE</scp> Blends for <scp>4D</scp> Printing

ABSTRACT In this work, the focus was on blending polyethylene terephthalate‐1,4‐cyclohexanedimethanol ester (PETG) with poly(ethylene‐co‐octene) (POE) by melt blending in different ratios to develop a novel thermo‐responsive shape memory polymer for 4D printing. SEM images of the blends showed that the compatibility of the blends increased with the increase of POE content and formed a co‐continuous structure at 70% POE content. Mechanical test results showed that the elongation at break of the blends increased significantly with increasing POE content, exhibiting enhanced toughness. Analysis of the DSC and TGA curves identified a thermal transition temperature of 80°C for the blends and confirmed that no thermal decomposition occurred during the 3D printing process. Shape memory performance tests showed that the PETG4/POE6 blend exhibited the best shape memory performance (shape fixation rate of 92.78% and shape recovery rate of 94.72%) and remained stable after 10 test cycles. In addition, the optimal 3D printing parameters were determined by studying printing parameters: layer thickness of 0.1 mm, filler density of 100%, hot‐bed temperature of 70°C, and printing speed of 80 mm/s. Under this parameter, the PETG4/POE6 blends exhibited excellent shape memory performance and rapidly recovered to the initial shape after complex deformation. In conclusion, this study provides a valuable theoretical basis and practical guidance for the development and application of similar shape memory materials in 4D printing.