# New Trends in 4D Printing: A Critical Review
## Nomenclature  
* 3 DP 3D Printing
* 4 DP 4D Printing
* 4 AM  Additive Manufacturing
* 4 DIW  Direct Ink Writing
* 4D Digital Light Processing
* 4F Fused Filament Fabrication
* 4D Printing  
* [PERSON] et al. (2022) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] 4D Printing of a Fully Biobased Shape Memory Copolyester via a UV-Assisted FDM Strategy. _ACS Sustain. Chem. Eng._**2022**, _10_, 6304-6312. [CrossRef]
* [PERSON] et al. (2020) [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; et al. Resilient yet entirely degradable gelatin-based biogels for soft robots and electronics. _Nat. Mater._**2020**, _19_, 1102-1109. [CrossRef] [PubMed]
* [PERSON] et al. (2017) [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON]; [PERSON]; et al. 4D printing of polymeric materials for tissue and organ regeneration. _Mater. Today_**2017**, _20_, 577-591. [CrossRef]
* [PERSON] et al. (2022) [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON]; [PERSON]; [PERSON] [PERSON] 4D Printing of Multicomponent Shape-Memory Polymer Formulations. _Appl. Sci._**2022**, _12_, 7880. [CrossRef]
* [PERSON] et al. (2018) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] 3D Printing of Highly Stretchable, Shape-Memory, and Self-Healing Elastomer toward Novel 4D Printing. _ACS Appl. Mater. Interfaces_**2018**, _10_, 7381-7388. [CrossRef] [PubMed]
* [PERSON] and [PERSON] (2021) [PERSON]; [PERSON] [PERSON] Hybrid hinge structure with elastic hinge on self-folding of 4D printing using a fused deposition modeling 3D printer. _Mater. Des._**2021**, _203_, 109605. [CrossRef]
* ISM (23) ISM. _In-Space Manufacturing_; NASA: Washington, DC, USA, (n.d.). Available online: [[https://www.nasa.gov/oem/inspacemanufacturing](https://www.nasa.gov/oem/inspacemanufacturing)]([https://www.nasa.gov/oem/inspacemanufacturing](https://www.nasa.gov/oem/inspacemanufacturing)) (accessed on 26 June 2023). * [PERSON] et al. (2021) [PERSON]; [PERSON]; [PERSON]; [PERSON] Significant roles of 4D printing using smart materials in the field of manufacturing. _Adv. Ind. Eng. Polym. Res._**2021**, \(4\), 301-311. [CrossRef]
* [PERSON] et al. (2022) [PERSON]; [PERSON]; [PERSON]; [PERSON] Comprehensive study on shape shifting behaviors in FDM-based 4D printing of bilayer structures. _Adv. Manuf. Technol._**2022**, _120_, 59-97. [CrossRef]
* [PERSON] et al. (2020) [PERSON]; [PERSON]; [PERSON]; [PERSON] 4D Printing Auxetic Metamaterials with Tunable, Programmable, and Reconfigurable Mechanical Properties. _Adv. Enunct. Mater._**2020**, _30_, 200-226. [CrossRef]
* [PERSON] et al. (2016) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Biomimetic 4D printing. _Nat. Mater._**2016**, _15_, 413-419. [CrossRef]
* [PERSON] et al. (2021) [PERSON]; [PERSON]; [PERSON]; [PERSON] Additive manufacturing landscape and materials perspective in 4D printing. _Int. J. Adv. Manuf. Technol._**2021**, _115_, 2973-2988. [CrossRef]
* [PERSON] et al. (2020) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] 4D printing of shape memory aliphatic copolyester via UV-assisted FDM strategy for medical protective devices. _Chem. Eng. J._**2020**, _396_, 125242. [CrossRef]
* [PERSON] et al. (2020) [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON] A review of 3D and 4D printing of natural fibre biocomposites. _Mater. Des._**2020**, _194_, 108911. [CrossRef]
* [PERSON] et al. (2021) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] 4D Printing of Stretchable Supercapacitors via Hybrid Composite Materials. _Adv. Mater. Technol._**2021**, \(6\), 2001055. [CrossRef]
* [PERSON] (2016) [PERSON]; [PERSON] Current status of 4D printing technology and the potential of light-reactive smart materials as 4D printable materials. _Virtual Phys. Prototyp._**2016**, _11_, 249-262. [CrossRef]
* [PERSON] et al.