Statement of Purpose: The ability to 3D print shape-memory polymers (SMPs) already pre-programmed for a subsequent function, such as a specific shape change, could have broad impact across diverse biomedical fields. Currently, 3D printed SMPs must be programmed in a separate step following the printing process, which requires that there be a means of physically deforming the SMP to impart a strain pattern inverse to that desired during recovery (Fig. 1). Available methods for producing strains in an SMP following printing are limited to simple deformations such as uniaxial compressions or tensions; creating complex strains is generally not feasible. However, recent studies suggest that the extrusion process during 3D printing can trap strains within the material
. With the long-term goal of program programing 1D, 2D, or 3D functional, single-material parts during, rather than following, printing, the goal of the present study was to quantify the extent to which strains can be trapped into simple 1D and 2D geometries during printing. To achieve this goal, we systematically studied the effect of temperature, printing speed, the multiplier print parameter, and fiber orientation on strain trapping in a cyto-and biocompatible SMP.