Figure - available from: Advanced Functional Materials
This content is subject to copyright. Terms and conditions apply.
Photoinhibition mechanism of lignin‐DCMs and the printability of lignin‐DCMs/PEGDA hydrogels. a) The curing depth of photoresins with different exposure doses. b) Real‐time conversion of double bond functional groups during photo‐crosslinking of PEGDA‐based photoresins. A DLP‐printed honeycomb scaffold with a height of 1 mm and layer thickness of 100 µm using c) 10%PEGDA, d) 10%PEGDA containing 1.0 mm tartrazine, and e–h) lignin‐DCMs/PEGDA photoresins. c1–h1) were the representative optical micrographs of the printed hydrogels. Scale bars in c–h) 1 mm and c1–h1) 100 µm. i) Comparison of the printing fidelity of PEGDA hydrogels (10 wt%) added with tartrazine and lignin‐DCMs.
Source publication
The design of lignin nanostructures where interfacial interactions enable enhanced entanglement of colloidal networks can broaden their applications in hydrogel‐based materials and light‐based 3D printing. Herein, an approach for fabricating surface‐active dendritic colloidal microparticles (DCMs) characterized by fibrous structures using nanostruc...
Citations
... It fails to fully replicate the hierarchical structure of wood, limiting its potential applications in areas that require high mechanical strength, anisotropic stiffness, and directional porosity. Another method, stereolithography (SLA) has been explored for wood-inspired additive manufacturing and employs UV-induced photopolymerization to fabricate high-resolution ligninreinforced composites 22,23,24 . In this approach, lignin is incorporated as an additive and mixed with a photocrosslinkable prepolymer, with lignin content reaching up to 5%. ...
Wood has long been used in furniture, construction, and structural applications due to its durability, aesthetic appeal, and natural abundance. Beyond these conventional uses, recent attention has focused on the lightweight nature, sustainability, and distinctive structural features of wood, including aligned fibrous architecture and intrinsic porosity, as desirable attributes for advanced material applications such as energy storage, transparent wood, high-strength components, and fluidic systems. However, the absence of methods to construct three-dimensional structures while preserving the intrinsic architecture of wood has limited its potential for advanced applications. Here, we introduce Wood-based Oriented Object Deposition (WOOD), a fabrication approach that enables the construction of three-dimensional wood structures while maintaining the natural fiber alignment and porosity of wood. WOOD adapts digital light processing (DLP) 3D printing by employing sliced wood sheets that are impregnated with a photocrosslinkable prepolymer. These sheets are sequentially stacked and selectively photopolymerized to form laminated structures with enhanced interfacial bonding and preserved anisotropic organization. Using WOOD, we demonstrate the fabrication of geometrically complex structures with tunable mechanical properties by leveraging the directional fiber orientation and porous network of natural wood. Furthermore, the capillary-driven fluid transport capability of wood is utilized to realize functional fluidic architectures. This approach provides a scalable strategy for producing high-resolution, mechanically robust, and intricately designed wood-based advanced devices while retaining the inherent characteristics.
... [1] Despite the challenges associated with the heterogeneous structure of lignin, considerable progress has been made in the application of this interesting aromatic biopolymer in many industry-demanded products, such as thermoplastics, thermosetting phenolic adhesives, nanoscale and microscale applications, carbon-based materials (e. g., carbon fibers and biochar), and advanced three-dimensional (3D) printing materials. [11][12][13][14][15][16][17] However, there still remains a gap between revenue from potential applications and the cost of lignin production, resulting in most technical lignin being burnt for energy as pulp production waste. [18] In this case, there is an urgent need to tap the value-added potential of lignin in highprofit and high-tech products to maximize the revenue of potential applications vs. lignin production costs. ...
... Recent research has shown that lignin has a great chance of being successfully used in photoreactions, such as macromonomers and nano-sized natural photo-absorbers for applications in vat photopolymerization-based 3D printing. [17,19,20] Moreover, the conjugated structure interactions in the aromatic pattern can enable lignin to exhibit interesting light-induced room temperature phosphorescence (RTP) phenomena and photothermal conversion properties, and lignin macromolecules are also promising building blocks for the synthesis of bio-based aggregation-induced emission luminogens. [21][22][23][24][25] In terms of photochemical reactions, literature studies have confirmed that lignin macromolecules can serve as electron donors and can generate radicals (e. g., o-semiquinone radicals, phenoxy radicals, benzyl radicals, etc) upon photoexcitation, which is expected to provide optimal solutions for a sustainable future of photochemistry development. ...
... [44] Compared with traditional thermalinitiated polymerization, photopolymerization offers numerous advantages, including fast manufacturing speed, high energy efficiency (e. g., low reaction temperatures), excellent control over the curing process (e. g., temporal control, spatial control of localized curing, and precise control over the polymer structure), and environmental benefits (e. g., low volatile organic compound emissions). [17] In this scenario, photopolymerization technology has rapidly evolved and been successfully applied in many high-tech and specialized applications, such as coating and electronic industry, dental and medical applications, lithography-based additive manufacturing (3D printing), microfabrication (e.g, microfluidic chips), and nanotechnology (e. g., nanoimprint lithography). [44,45] Figure 1. ...
Lignin, the most abundant aromatic biopolymer, is emerging as a mainstay of the upcoming revolution in sustainable materials processing. Despite the inherent challenges associated with the heterogeneous structure of lignin, significant progress has recently been made in developing innovative strategies to valorize this fascinating aromatic biopolymer to deliver industry‐demanded products via photoreactions. The purpose of this concept article is to unravel insights into these creative approaches in lignin‐assisted photoreactions, focusing on photopolymerization to construct functional polymeric materials and photoreduction to provide valuable chemicals, wherein lignin serves as a macromolecular photoinitiator and a reductive photocatalyst, respectively. The existing strategies for improving the photochemical quantum yield of lignin in photopolymerization and harnessing lignin macromolecules as photoresponsive polymers to facilitate electron transfer in photocatalytic reactions are also summarized. In the future, such photochemical lignin valorization concepts could potentially provide new possibilities for achieving a profitable value chain for integrated biorefinery processes.
Amine-functionalized solid adsorbents (NFSAs) from green and renewable biomass have been proven to be a significant breakthrough in utilizing renewable resources in the carbon capture and storage field. Lignin, a...
Since its invention in the 1980s, photopolymerization-based 3D printing has attracted significant attention for its capability to fabricate complex microstructures with high precision, by leveraging light patterning to initiate polymerization and cross-linking in liquid resin materials. Such precision makes it particularly suitable for biomedical applications, in particular, advanced and customized drug delivery systems. This review summarizes the latest advancements in photopolymerization 3D printing technology and the development of biocompatible and/or biodegradable materials that have been used or shown potential in the field of drug delivery. The drug loading methods and release characteristics of the 3D printing drug delivery systems are summarized. Importantly, recent trends in the drug delivery applications based on photopolymerization 3D printing, including oral formulations, microneedles, implantable devices, microrobots and recently emerging systems, are analyzed. In the end, the challenges and opportunities in photopolymerization 3D printing for customized drug delivery are discussed.
