Towards a Design Framework for Multifunctional Shape Memory Polymer Based Product in the Era of 4D Printing

Shape-memory polymers (SMPs) as stimuli-responsive shape-changing materials gained significant interest in recent years. Their developments have challenged the conventional understanding of the polymer effect and have further enhanced and broadened the applications of the smart materials. Nowadays, 4D printing is seen as an emerging technology that combines smart materials and additive manufacturing, which can be used to design active mechanical structures. It provides tremendous potential for engineering applications which is capable of producing complex, stimuli-responsive 3D structures. While many “ad hoc” designs of 4D printed solutions have been progressively developed for a specific process, the general approach of additive manufacturing that integrates smart materials in real time across an entire product development process is not pervasive in the industry. To solve this issue, the authors propose a general 4D printing oriented framework for the design of multi-functional SMPs architectures. This framework is not intended to be an exhaustive and specific instruction but is instead a means to motivate these designers to seek the process of applying these unique functional materials to their own designs and applications. It will be useful and give more insight into the design process of the SMP device.