4D Printing of Ultra‐High Performance Shape Memory Polymer for Space Applications

Developing thermoplastic polyimide (TPI), capable of handling space conditions, through 4D printing is challenging due to its high melting temperature and inherent viscosity. This study presents 4D printing of TPI for shape memory investigation under repetitive cycles for the first time, exploring its potential for self‐deployable hinges in space devices. 4D‐printed TPI exhibits outstanding shape memory effect (SME) with shape fixity (Rf) up to 100% and shape recovery (Rr) of 100% in first cycle. Rf is noted to be increasing up to third cycle and then fixed to 100% up to tenth cycle, while Rr shows a decreasing trend in subsequent cycle with a drop of 37% in tenth cycle. Moreover, it exhibits extremely high glass‐transition temperature, Tg = 263.10 °C, degradation temperature, Td = 520 °C, and storage modulus of 1600 MPa. Among existing high‐performance (HP) and conventional shape memory polymers (SMPs), 3D‐printed TPI exhibits superior performance. Tg of the TPI is found to be 66.52%, 107.16%, and 62.41%, higher than existing HP‐SMPs, polyether ether ketone (Tg = 158 °C), polyamide (Tg = 127 °C), and polyether ketone ketone (Tg = 162 °C), respectively. This investigation reveals a novel characteristic, the SME, of 4D‐printed TPI with ultra‐high Tg and Td, demonstrating suitability for self‐deployable hinges, contributing to materials engineering and 4D printing. This study explores the shape memory effect of 4D‐printed thermoplastic polyimide (TPI) through repetitive cycles to investigate its potential for self‐deployable hinges in space devices. The 4D‐printed TPI exhibited a great potential for replacing the existing high‐performance shape memory polymers like polyether ether ketone, polyamide, and polyether ketone ketone. A thorough investigation has been undertaken in 4D printing field.