Cersoli Trenton, Cresanto Alexis, Herberger Callan, MacDonald Eric, Cortes Pedro
Civil/Environmental & Chemical Engineering, Rayen School of Engineering, Youngstown State University, Youngstown, OH 44555, USA.
Electrical Engineering, Rayen School of Engineering, Youngstown State University, Youngstown, OH 44555, USA.
Micromachines (Basel). 2021 Jan 15;12(1):87. doi: 10.3390/mi12010087.
Shape memory polymers (SMPs) are materials capable of changing their structural configuration from a fixed shape to a temporary shape, and vice versa when subjected to a thermal stimulus. The present work has investigated the 3D printing process of a shape memory polymer (SMP)-based polyurethane using a material extrusion technology. Here, SMP pellets were fed into a printing unit, and actuating coupons were manufactured. In contrast to the conventional film-casting manufacturing processes of SMPs, the use of 3D printing allows the production of complex parts for smart electronics and morphing structures. In the present work, the memory performance of the actuating structure was investigated, and their fundamental recovery and mechanical properties were characterized. The preliminary results show that the assembled structures were able to recover their original conformation following a thermal input. The printed parts were also stamped with a QR code on the surface to include an unclonable pattern for addressing counterfeit features. The stamped coupons were subjected to a deformation-recovery shape process, and it was observed that the QR code was recognized after the parts returned to their original shape. The combination of shape memory effect with authentication features allows for a new dimension of counterfeit thwarting. The 3D-printed SMP parts in this work were also combined with shape memory alloys to create a smart actuator to act as a two-way switch to control data collection of a microcontroller.
形状记忆聚合物（SMPs）是一种材料，能够在受到热刺激时将其结构构型从固定形状转变为临时形状，反之亦然。目前的工作研究了使用材料挤出技术对基于形状记忆聚合物（SMP）的聚氨酯进行3D打印的过程。在这里，将SMP颗粒送入打印单元，并制造驱动试样。与传统的SMPs流延膜制造工艺相比，3D打印的使用允许生产用于智能电子和变形结构的复杂部件。在目前的工作中，研究了驱动结构的记忆性能，并对其基本恢复和力学性能进行了表征。初步结果表明，组装结构在热输入后能够恢复其原始构象。打印部件的表面还印有二维码，以包含用于解决假冒特征的不可克隆图案。对冲压试样进行变形-恢复形状过程，观察到部件恢复到原始形状后二维码仍能被识别。形状记忆效应与认证特征的结合为防伪提供了新的维度。这项工作中的3D打印SMP部件还与形状记忆合金相结合，创建了一个智能致动器，用作双向开关来控制微控制器的数据采集。
