skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: Dynamic bond exchangeable thermoset vitrimers in 3D‐printing
Abstract Dynamic bond exchanging vitrimers have emerged recently due to their malleability, self‐heal ability, recyclability, and mechanical stability. Likewise, 3D printing is consciously introduced at different platforms for ease of fabrication, high throughput, cost‐effectiveness, and waste reduction. These two distinctive techniques have recently made their consensus performance, resulting from a phenomenal change in the printing field. Conventionally, thermoplastic inks have been primarily used in 3D printing, owing to their effortless processability. At the same time, thermosets were utilized for their superior mechanical strength. However, these two essential properties have been required to be presented in the printed material. In that scenario, thermoset vitrimer materials have been introduced in 3D printing, where malleability and mechanical stability have been observed in the same material. Thus, this article details the recent vitrimer material included with the different 3D printing system systems with their reported results to understand and make them widespread. Eventually, the outlook and perspectives could be helpful to understand and enhance this specific field.  more » « less
Award ID(s):
1735968
PAR ID:
10525161
Author(s) / Creator(s):
;
Publisher / Repository:
Journal of Applied Polymer Science
Date Published:
Journal Name:
Journal of Applied Polymer Science
Volume:
140
Issue:
2
ISSN:
0021-8995
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Leach, J Kent (Ed.)
    Abstract A direct and comprehensive comparative study on different 3D printing modalities was performed. We employed two representative 3D printing modalities, laser‐ and extrusion‐based, which are currently used to produce patient‐specific medical implants for clinical translation, to assess how these two different 3D printing modalities affect printing outcomes. The same solid and porous constructs were created from the same biomaterial, a blend of 96% poly‐ε‐caprolactone (PCL) and 4% hydroxyapatite (HA), using two different 3D printing modalities. Constructs were analyzed to assess their printing characteristics, including morphological, mechanical, and biological properties. We also performed an in vitro accelerated degradation study to compare their degradation behaviors. Despite the same input material, the 3D constructs created from different 3D printing modalities showed distinct differences in morphology, surface roughness and internal void fraction, which resulted in different mechanical properties and cell responses. In addition, the constructs exhibited different degradation rates depending on the 3D printing modalities. Given that each 3D printing modality has inherent characteristics that impact printing outcomes and ultimately implant performance, understanding the characteristics is crucial in selecting the 3D printing modality to create reliable biomedical implants. 
    more » « less
  2. null (Ed.)
    Purpose This paper aims to summarize the up-to-date research performed on combinations of various biofibers and resin systems used in different three-dimensional (3D) printing technologies, including powder-based, material extrusion, solid-sheet and liquid-based systems. Detailed information about each process, including materials used and process design, are described, with the resultant products’ mechanical properties compared with those of 3D-printed parts produced from pure resin or different material combinations. In most processes introduced in this paper, biofibers are beneficial in improving the mechanical properties of 3D-printed parts and the biodegradability of the parts made using these green materials is also greatly improved. However, research on 3D printing of biofiber-reinforced composites is still far from complete, and there are still many further studies and research areas that could be explored in the future. Design/methodology/approach The paper starts with an overview of the current scenario of the composite manufacturing industry and then the problems of advanced composite materials are pointed out, followed by an introduction of biocomposites. The main body of the paper covers literature reviews of recently emerged 3D printing technologies that were applied to biofiber-reinforced composite materials. This part is classified into subsections based on the form of the starting materials used in the 3D printing process. A comprehensive conclusion is drawn at the end of the paper summarizing the findings by the authors. Findings Most of the biofiber-reinforced 3D-printed products exhibited improved mechanical properties than products printed using pure resin, indicating that biofibers are good replacements for synthetic ones. However, synthetic fibers are far from being completely replaced by biofibers due to several of their disadvantages including higher moisture absorbance, lower thermal stability and mechanical properties. Many studies are being performed to solve these problems, yet there are still some 3D printing technologies in which research concerning biofiber-reinforced composite parts is quite limited. This paper unveils potential research directions that would further develop 3D printing in a sustainable manner. Originality/value This paper is a summary of attempts to use biofibers as reinforcements together with different resin systems as the starting material for 3D printing processes, and most of the currently available 3D printing techniques are included herein. All of these attempts are solutions to some principal problems with current 3D printing processes such as the limit in the variety of materials and the poor mechanical performance of 3D printed parts. Various types of biofibers are involved in these studies. This paper unveils potential research directions that would further widen the use of biofibers in 3D printing in a sustainable manner. 
    more » « less
  3. Abstract The majority of 3D‐printed biodegradable biomaterials are brittle, limiting their application to compliant tissues. Poly(glycerol sebacate) acrylate (PGSA) is a synthetic biocompatible elastomer and compatible with light‐based 3D printing. In this article, digital‐light‐processing (DLP)‐based 3D printing is employed to create a complex PGSA network structure. Nature‐inspired double network (DN) structures consisting of interconnected segments with different mechanical properties are printed from the same material in a single shot. Such capability has not been demonstrated by any other fabrication techniques so far. The biocompatibility of PGSA is confirmed via cell‐viability analysis. Furthermore, a finite‐element analysis (FEA) model is used to predict the failure of the DN structure under uniaxial tension. FEA confirms that the DN structure absorbs 100% more energy before rupture by using the soft segments as sacrificial elements while the hard segments retain structural integrity. Using the FEA‐informed design, a new DN structure is printed and tensile test results agree with the simulation. This article demonstrates how geometrically‐optimized material design can be easily and rapidly constructed by DLP‐based 3D printing, where well‐defined patterns of different stiffnesses can be simultaneously formed using the same elastic biomaterial, and overall mechanical properties can be specifically optimized for different biomedical applications. 
    more » « less
  4. Abstract Recent advances in computational design and 3D printing enable the fabrication of polymer lattices with high strength‐to‐weight ratio and tailored mechanics. To date, 3D lattices composed of monolithic materials have primarily been constructed due to limitations associated with most commercial 3D printing platforms. Here, freeform fabrication of multi‐material polymer lattices via embedded three‐dimensional (EMB3D) printing is demonstrated. An algorithm is developed first that generates print paths for each target lattice based on graph theory. The effects of ink rheology on filamentary printing and the effects of the print path on resultant mechanical properties are then investigated. By co‐printing multiple materials with different mechanical properties, a broad range of periodic and stochastic lattices with tailored mechanical responses can be realized opening new avenues for constructing architected matter. 
    more » « less
  5. Abstract Natural organisms have evolved a series of versatile functional biomaterials and structures to cope with survival crises in their living environment, exhibiting outstanding properties such as superhydrophobicity, anisotropy, and mechanical reinforcement, which have provided abundant inspiration for the design and fabrication of next‐generation multi‐functional devices. However, the lack of available materials and limitations of traditional manufacturing methods for complex multiscale structures have hindered the progress in bio‐inspired manufacturing of functional structures. As a revolutionary emerging manufacturing technology, additive manufacturing (i.e., 3D printing) offers high design flexibility and manufacturing freedom, providing the potential for the fabrication of intricate, multiscale, hierarchical, and multi‐material structures. Herein, a comprehensive review of current 3D printing of surface/interface structures, covering the applied materials, designs, and functional applications is provided. Several bio‐inspired surface structures that have been created using 3D printing technology are highlighted and categorized based on their specific properties and applications, some properties can be applied to multiple applications. The optimized designs of these 3D‐printed bio‐inspired surfaces offer a promising prospect of low‐cost, high efficiency, and excellent performance. Finally, challenges and opportunities in field of fabricating functional surface/interface with more versatile functional material, refined structural design, and better cost‐effective are discussed. 
    more » « less