Thermal transport in 3D printed shape memory polymer metamaterials

Shape memory polymers are gaining significant interest as one of the major constituent materials for emerging field 4D printing. While 3D-printed metamaterials with shape show unique thermomechanical behaviors, their thermal transport properties have received relatively little attention. Here, we that in strongly depends on shape, solid volume fraction, and temperature radiation plays a critical role. Our infrared thermography measurements reveal mechanisms varying shapes from bulk to octet-truss Kelvin-foam microlattices fractions 4%–7% over range 30–130 °C. The conductivity increases 0.24 0.31 W m?1 K?1 around glass transition temperature, which primary mechanism is phase-dependent change conduction. On contrary, dominates heat transfer its contribution structure ranges 68% 83% 59% 76% same range. We attribute this role combination high emissivity surface-to-volume ratio polymer microlattices. work also presents an effective medium approach explain experimental results model shapes, fractions, temperatures. These findings provide new insights into understanding 4D-printed exploring design space metamaterials.