Photopolymerization in 3D Printing
20 Feb 2019-Vol. 1, Iss: 4, pp 593-611
TL;DR: The field of 3D printing is continuing its rapid development in both academic and industrial research environments as mentioned in this paper, which offers flexibility over the final properties of the 3D printed materials (such as optical, chemical and mechanical properties) using versatile polymer chemistry.
Abstract: The field of 3D printing is continuing its rapid development in both academic and industrial research environments. The development of 3D printing technologies has opened new implementations in rapid prototyping, tooling, dentistry, microfluidics, biomedical devices, tissue engineering, drug delivery, etc. Among different 3D printing techniques, photopolymerization-based process (such as stereolithography and digital light processing) offers flexibility over the final properties of the 3D printed materials (such as optical, chemical, and mechanical properties) using versatile polymer chemistry. The strategy behind the 3D photopolymerization is based on using monomers/oligomers in liquid state (in the presence of photoinitiators) that can be photopolymerized (via radical or cationic mechanism) upon exposure to light source of different wavelengths (depending on the photoinitiator system). An overview of recent evolutions in the field of photopolymerization-based 3D printing and highlights of novel 3D print...
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TL;DR: In this article, three photopolymerization technologies, namely, stereolithography (SLA), digital light processing (DLP), and continuous digital light process (CDLP), are reviewed.
Abstract: Additive manufacturing (3D printing) has significantly changed the prototyping process in terms of technology, construction, materials, and their multiphysical properties. Among the most popular 3D printing techniques is vat photopolymerization, in which ultraviolet (UV) light is deployed to form chains between molecules of liquid light-curable resin, crosslink them, and as a result, solidify the resin. In this manuscript, three photopolymerization technologies, namely, stereolithography (SLA), digital light processing (DLP), and continuous digital light processing (CDLP), are reviewed. Additionally, the after-cured mechanical properties of light-curable resin materials are listed, along with a number of case studies showing their applications in practice. The manuscript aims at providing an overview and future trend of the photopolymerization technology to inspire the readers to engage in further research in this field, especially regarding developing new materials and mathematical models for microrods and bionic structures.
191 citations
04 Jun 2020
TL;DR: This review paper summarizes a few typical applications of P μSL including mechanical metamaterials, optical components, 4D printing, bioinspired materials and biomedical applications, and offers perspectives on the directions of the further development of PμSL based 3D printing technology.
Abstract: Projection Micro Stereolithography (PμSL) is a high-resolution (up to 0.6 μm) 3D printing technology based on area projection triggered photopolymerization, and capable of fabricating complex 3D architectures covering multiple scales and with multiple materials. This paper reviews the recent development of the PμSL based 3D printing technologies, together with the related applications. It introduces the working principle, the commercialized products, and the recent multiscale, multimaterial printing capability of PμSL as well as some functional photopolymers that are suitable to PμSL. This review paper also summarizes a few typical applications of PμSL including mechanical metamaterials, optical components, 4D printing, bioinspired materials and biomedical applications, and offers perspectives on the directions of the further development of PμSL based 3D printing technology.
174 citations
Cites background from "Photopolymerization in 3D Printing"
...The photopolymerization is a free radical based polymerization, and includes four main steps: radical generation, initiation, propagation, and termination [62, 63]....
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TL;DR: In this work, crosslinking methods used in 3D bioprinting studies are reviewed, parameters that affect bioink chemistry are discussed, and the potential toward improving crossl linking outcomes and construct performance is highlighted.
Abstract: Three-dimensional (3D) bioprinting has recently advanced as an important tool to produce viable constructs that can be used for regenerative purposes or as tissue models. To develop biomimetic and sustainable 3D constructs, several important processing aspects need to be considered, among which crosslinking is most important for achieving desirable biomechanical stability of printed structures, which is reflected in subsequent behavior and use of these constructs. In this work, crosslinking methods used in 3D bioprinting studies are reviewed, parameters that affect bioink chemistry are discussed, and the potential toward improving crosslinking outcomes and construct performance is highlighted. Furthermore, current challenges and future prospects are discussed. Due to the direct connection between crosslinking methods and properties of 3D bioprinted structures, this Review can provide a basis for developing necessary modifications to the design and manufacturing process of advanced tissue-like constructs in future.
150 citations
TL;DR: Improved tissue adhesion of the bioinspired MN allows for more stable and robust performance for drug delivery, biofluid collection, and biosensing.
143 citations
TL;DR: An overview of the vat polymerization techniques, their unique applications in the fields of drug delivery and medical device fabrication, material examples and the advantages they provide within healthcare, is provided.
136 citations
References
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70 citations
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70 citations
TL;DR: A novel hydrogel system based on hyaluronic acid vinyl esters (HA-VE), which enabled fast 2PP-fabrication of 3D hydrogels constructs with μm-scale accuracy and demonstrated low cytotoxicity, high reactivity and good biodegradability makes HA-VE promising candidates for biological applications in cell culture and tissue engineering.
68 citations
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68 citations