Applications of 3D Printing for Polymers

A special issue of Polymers (ISSN 2073-4360). This special issue belongs to the section "Biomacromolecules, Biobased and Biodegradable Polymers".

Deadline for manuscript submissions: closed (31 August 2022) | Viewed by 109851

Special Issue Editor

Mechanical Engineering, Texas Tech University, Lubbock, TX 79409, USA
Interests: engineering design; 3D printing; additive manufacturing; lattices; tissue scaffolds; finite element analysis; mechanics; polymers; computation; medicine
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear colleagues,

Polymer 3D printing is an emerging technology in research and industry for diverse applications ranging from prototypes to end-use designs. 3D printing uses additive manufacturing processes to fabricate designed parts using polymer materials including thermoplastics, thermosets, elastomers, biomaterials, and more. Polymer printing is advantageous for its wide range of material properties, inexpensive processing costs, and potential for complex design fabrication. Common applications for polymer 3D printing include prosthetics in the medical industry, lightweight/high-strength parts for aerospace applications, and inexpensive customized parts for consumers. 

Although 3D printing techniques have advanced substantially in previous years, there are still many avenues of research and challenges in materials, processing, and design to address. In materials there is the need for the further creation of polymers with advantageous properties and for measuring the achieved performance of existing printed polymers. Processing challenges include the development of new ways of depositing materials to form a structure and assessing how printing processes influence end part performance. Addressing challenges in designing polymers to form lattices, multi-material structures, and stimuli-responsive parts will support applications that utilize these designed features for improved performance and functionality. Addressing these areas of research and further challenges will open new doors for fully understanding and using 3D-printed polymers to the fullest of their potential in diverse applications.

This Special Issue welcomes papers on a wide variety of topics in polymer applications in 3D printing and research that supports relevant fundamental advances; these applications can range from diverse industries including but not limited to medical, aerospace, automobile, electronics, and consumer with 3D printing processes for extrusion, resin, and powder-based fabrication approaches.

Dr. Paul F. Egan
Guest Editor

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Keywords

  • design
  • 3D printing
  • additive manufacturing
  • polymer applications
  • functional materials
  • lattices
  • mechanics
  • plastics
  • healthcare

Published Papers (17 papers)

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Editorial

Jump to: Research, Review

4 pages, 504 KiB  
Editorial
Special Issue Editorial: Applications of 3D Printing for Polymers
by Paul F. Egan
Polymers 2023, 15(7), 1638; https://0-doi-org.brum.beds.ac.uk/10.3390/polym15071638 - 25 Mar 2023
Cited by 3 | Viewed by 1089
Abstract
Polymer 3D printing is an emerging technology highly relevant in diverse industries, including medicine, electronics, and robotics [...] Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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Research

Jump to: Editorial, Review

14 pages, 5735 KiB  
Article
Influence of CAD/CAM Milling and 3D-Printing Fabrication Methods on the Mechanical Properties of 3-Unit Interim Fixed Dental Prosthesis after Thermo-Mechanical Aging Process
by Passent Ellakany, Shaimaa M. Fouda, Amr A. Mahrous, Maram A. AlGhamdi and Nourhan M. Aly
Polymers 2022, 14(19), 4103; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14194103 - 30 Sep 2022
Cited by 25 | Viewed by 2485
Abstract
This study assessed the influence of CAD/CAM milling and 3D-printing fabrication methods on mechanical properties of 3-unit interim fixed dental prosthesis (IFDPs) after thermo-mechanical aging. Forty 3-unit IFDPs were fabricated on a mandibular right second premolar and second molar of a typodont cast. [...] Read more.
This study assessed the influence of CAD/CAM milling and 3D-printing fabrication methods on mechanical properties of 3-unit interim fixed dental prosthesis (IFDPs) after thermo-mechanical aging. Forty 3-unit IFDPs were fabricated on a mandibular right second premolar and second molar of a typodont cast. Samples were fabricated from the following materials; auto-polymerized polymethyl methacrylate (conventional resin), CAD/CAM PMMA (milled resin) and two different CAD/CAM 3D-printed composite resins; digital light processing Asiga (DLP AS) and stereolithography NextDent (SLA ND). Mechanical properties were compared between the studied materials using Kruskal–Wallis test, followed by multiple pairwise comparisons using Bonferroni adjusted significance. There was a significant difference in flexural strength and microhardness between the studied materials (p < 0.001), with the highest mean ± SD reported in the milled IFDPs (174.42 ± 3.39, 27.13 ± 0.52), and the lowest in the conventional IFDPs (98.02 ± 6.1, 15.77 ± 0.32). Flexural strengths differed significantly between the conventional IFDPs and all materials except DLP AS. The highest elastic modulus was recorded in the milled group, and the lowest in the SLA ND group (p = 0.02). In conclusion, superior flexural strength, elastic modulus, and hardness were reported for milled IFDPs. SLA ND printed IFDPs showed comparable mechanical properties to milled ones except for the elastic modulus. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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15 pages, 5813 KiB  
Article
Investigation of Low-Cost FDM-Printed Polymers for Elevated-Temperature Applications
by Jan Lukas Storck, Guido Ehrmann, Uwe Güth, Jana Uthoff, Sarah Vanessa Homburg, Tomasz Blachowicz and Andrea Ehrmann
Polymers 2022, 14(14), 2826; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14142826 - 11 Jul 2022
Cited by 6 | Viewed by 1740
Abstract
While fused deposition modeling (FDM) and other relatively inexpensive 3D printing methods are nowadays used in many applications, the possible areas of using FDM-printed objects are still limited due to mechanical and thermal constraints. Applications for space, e.g., for microsatellites, are restricted by [...] Read more.
While fused deposition modeling (FDM) and other relatively inexpensive 3D printing methods are nowadays used in many applications, the possible areas of using FDM-printed objects are still limited due to mechanical and thermal constraints. Applications for space, e.g., for microsatellites, are restricted by the usually insufficient heat resistance of the typical FDM printing materials. Printing high-temperature polymers, on the other hand, necessitates special FDM printers, which are not always available. Here, we show investigations of common polymers, processible on low-cost FDM printers, under elevated temperatures of up to 160 °C for single treatments. The polymers with the highest dimensional stability and mechanical properties after different temperature treatments were periodically heat-treated between -40 °C and +80 °C in cycles of 90 min, similar to the temperature cycles a microsatellite in the low Earth orbit (LEO) experiences. While none of the materials under investigation fully maintains its dimensions and mechanical properties, filled poly(lactic acid) (PLA) filaments were found most suitable for applications under these thermal conditions. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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18 pages, 5292 KiB  
Article
Experimental Modal Analysis and Characterization of Additively Manufactured Polymers
by Hieu Tri Nguyen, Kelly Crittenden, Leland Weiss and Hamzeh Bardaweel
Polymers 2022, 14(10), 2071; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14102071 - 19 May 2022
Cited by 12 | Viewed by 1799
Abstract
Modern 3D printed components are finding applications in dynamic structures. These structures are often subject to dynamic loadings. To date, research has mostly focused on investigating the mechanical properties of these 3D printed structures with minimum attention paid to their modal analysis. This [...] Read more.
Modern 3D printed components are finding applications in dynamic structures. These structures are often subject to dynamic loadings. To date, research has mostly focused on investigating the mechanical properties of these 3D printed structures with minimum attention paid to their modal analysis. This work is focused on performing experimental modal analysis of 3D printed structures. The results show that the adhesion type has the most significant impact on the vibration response and parameters obtained from the modal analysis. The average dynamic modulus, natural frequency, and damping coefficient increased by approximately 12.5%, 5.5%, and 36%, respectively, for the specimens printed using skirt adhesion compared to those printed using raft adhesion. SEM analysis suggests that the 3D printed specimens with skirt adhesion yielded flattened layers, while raft adhesion resulted in rounded layers. The flattened layers of the specimens with skirt adhesion are likely an indication of an enhanced heat transfer between the 3D printer bed and the specimen. The printed specimens with skirt adhesion are in direct contact with the printer bed during the printing process. This enhances the heat transfer between the specimen and the printer bed, causing the layers to flatten out. The enhanced heat transfer yields a better inter-layer diffusion, resulting in improved physical bonding at the layers’ interface. The improved bonding yields higher stiffnesses and natural frequencies. For the specimens with skirt adhesion, the improved heat transfer process is also likely responsible for the enhanced damping properties. The strengthened inter-layer bonding at the layer–layer interface provides better energy dissipation along the contact lines between the layers. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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20 pages, 7489 KiB  
Article
Implementation of Microwave Circuits Using Stereolithography
by Germán Torregrosa-Penalva, Héctor García-Martínez, Ángela E. Ortega-Argüello, Alberto Rodríguez-Martínez, Arnau Busqué-Nadal and Ernesto Ávila-Navarro
Polymers 2022, 14(8), 1612; https://0-doi-org.brum.beds.ac.uk/10.3390/polym14081612 - 15 Apr 2022
Cited by 3 | Viewed by 2246
Abstract
In this work, the use of additive manufacturing techniques through stereolithography for the manufacture of high-frequency circuits and devices is presented. Both the resin and the 3D printer used in this research are general-purpose commercial materials, not specifically intended for the implementation of [...] Read more.
In this work, the use of additive manufacturing techniques through stereolithography for the manufacture of high-frequency circuits and devices is presented. Both the resin and the 3D printer used in this research are general-purpose commercial materials, not specifically intended for the implementation of microwave networks. The manufacturing and metallization procedures used to produce substrates for the design of planar microwave circuits are described, introducing the characterization process carried out to determine the electrical properties of the resin used. The ultrasonic techniques that allow the structural analysis of the manufactured substrates are also described. The electrical characterization provides a relative dielectric permittivity of 3.25 and a loss tangent of 0.03 for the resin used. In addition, the structural analysis shows a homogeneity and a finish of the manufactured parts that is not achievable using fused deposition modeling techniques. Finally, as a proof of concept, the design and manufacture of a complex geometry stepped impedance filter on a multi-height substrate using stereolithography techniques is presented, which allows for reducing the size of the traditional implementation of the same filter while maintaining its high-frequency response performance. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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14 pages, 2234 KiB  
Article
Characterization of Hydrophilic Polymers as a Syringe Extrusion 3D Printing Material for Orodispersible Film
by Pattaraporn Panraksa, Sheng Qi, Suruk Udomsom, Pratchaya Tipduangta, Pornchai Rachtanapun, Kittisak Jantanasakulwong and Pensak Jantrawut
Polymers 2021, 13(20), 3454; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13203454 - 09 Oct 2021
Cited by 18 | Viewed by 3006
Abstract
The application of hydrophilic polymers in designing and three-dimensional (3D) printing of pharmaceutical products in various dosage forms has recently been paid much attention. Use of hydrophilic polymers and syringe extrusion 3D printing technology in the fabrication of orodispersible films (ODFs) might hold [...] Read more.
The application of hydrophilic polymers in designing and three-dimensional (3D) printing of pharmaceutical products in various dosage forms has recently been paid much attention. Use of hydrophilic polymers and syringe extrusion 3D printing technology in the fabrication of orodispersible films (ODFs) might hold great potential in rapid drug delivery, personalized medicine, and manufacturing time savings. In this study, the feasibility of 3D-printed ODFs fabrication through a syringe extrusion 3D printing technique and using five different hydrophilic polymers (e.g., hydroxypropyl methylcellulose E15, hydroxypropyl methylcellulose E50, high methoxyl pectin, sodium carboxymethylcellulose, and hydroxyethylcellulose) as film-forming polymers and printing materials has been investigated. Rheology properties and printability of printing gels and physicochemical and mechanical properties of 3D-printed ODFs were evaluated. Amongst the investigated hydrophilic polymers, sodium carboxymethylcellulose at a concentration of 5% w/v (SCMC-5) showed promising results with a good printing resolution and accurate dimensions of the 3D-printed ODFs. In addition, SCMC-5 3D-printed ODFs exhibited the fastest disintegration time within 3 s due to high wettability, roughness and porosity on the surface. However, the results of the mechanical properties study showed that SCMC-5 3D printed ODFs were rigid and brittle, thus requiring special packaging to prevent them from any damage before practical use. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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20 pages, 15868 KiB  
Article
Analysis of AM Parameters on Surface Roughness Obtained in PLA Parts Printed with FFF Technology
by Irene Buj-Corral, Xavier Sánchez-Casas and Carmelo J. Luis-Pérez
Polymers 2021, 13(14), 2384; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13142384 - 20 Jul 2021
Cited by 17 | Viewed by 3435
Abstract
Fused filament fabrication (FFF) 3D printing technology allows very complex parts to be obtained at a relatively low cost and in reduced manufacturing times. In the present work, the effect of main 3D printing parameters on roughness obtained in curved surfaces is addressed. [...] Read more.
Fused filament fabrication (FFF) 3D printing technology allows very complex parts to be obtained at a relatively low cost and in reduced manufacturing times. In the present work, the effect of main 3D printing parameters on roughness obtained in curved surfaces is addressed. Polylactic acid (PLA) hemispherical cups were printed with a shape similar to that of the acetabular part of the hip prostheses. Different experiments were performed according to a factorial design of experiments, with nozzle diameter, temperature, layer height, print speed and extrusion multiplier as variables. Different roughness parameters were measured—Ra, Rz, Rku, Rsk—both on the outer surface and on the inner surface of the parts. Arithmetical mean roughness value Ra and greatest height of the roughness profile Rz are usually employed to compare the surface finish among different manufacturing processes. However, they do not provide information about the shape of the roughness profile. For this purpose, in the present work kurtosis Rku and skewness Rsk were used. If the height distribution in a roughness profile follows a normal law, the Rku parameter will take a value of 3. If the profile distribution is symmetrical, the Rsk parameter will take a value of 0. Adaptive neural fuzzy inference system (ANFIS) models were obtained for each response. Such models are often employed to model different manufacturing processes, but their use has not yet been extended to 3D printing processes. All roughness parameters studied depended mainly on layer height, followed by nozzle diameter. In the present work, as a general trend, Rsk was close to but lower than 0, while Rku was slightly lower than 3. This corresponds to slightly higher valleys than peaks, with a rounded height distribution to some degree. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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28 pages, 26055 KiB  
Article
Analysis of Raised Feature Failures on 3D Printed Injection Moulds
by Anurag Bagalkot, Dirk Pons, Digby Symons and Don Clucas
Polymers 2021, 13(10), 1541; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13101541 - 11 May 2021
Cited by 15 | Viewed by 3411
Abstract
Background: Polymer-based 3D Printed Injection Mould (3DIM) inserts are used as a cost-effective method for low volume injection moulding (50–500 parts). However, abrupt failure leading to a short tool life is a common shortcoming of 3DIM. Need: The underlying causes of raised feature [...] Read more.
Background: Polymer-based 3D Printed Injection Mould (3DIM) inserts are used as a cost-effective method for low volume injection moulding (50–500 parts). However, abrupt failure leading to a short tool life is a common shortcoming of 3DIM. Need: The underlying causes of raised feature failures on 3DIM are not well known. Failure is commonly attributed to bending or shearing of raised features on the tool. Understanding the causes may help in delaying the failure and increasing tool life. Approach: Tool failure was analysed from a first-principles perspective, using pressure and temperature fields as determined by mould flow simulation. Experimental results were also obtained for two types of tool material (Visijet M3-X and Digital ABS) with polycarbonate (Lexan 943A) as the part material. Findings: Results find against the idea that pin failure in 3DIM tools is caused by bending and shear failures induced by injection pressures. We also conclude that failure of raised features is not necessarily an abrupt failure as mentioned in the literature. Originality: The generally accepted explanation for the failure of raised features in 3DIM tooling is that injection pressures cause bending and shear failure. This paper disconfirms this notion on theoretical and experimental grounds. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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13 pages, 2894 KiB  
Article
Pressure Orientation-Dependent Recovery of 3D-Printed PLA Objects with Varying Infill Degree
by Guido Ehrmann and Andrea Ehrmann
Polymers 2021, 13(8), 1275; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13081275 - 14 Apr 2021
Cited by 14 | Viewed by 2082
Abstract
Poly(lactic acid) is not only one of the most often used materials for 3D printing via fused deposition modeling (FDM), but also a shape-memory polymer. This means that objects printed from PLA can, to a certain extent, be deformed and regenerate their original [...] Read more.
Poly(lactic acid) is not only one of the most often used materials for 3D printing via fused deposition modeling (FDM), but also a shape-memory polymer. This means that objects printed from PLA can, to a certain extent, be deformed and regenerate their original shape automatically when they are heated to a moderate temperature of about 60–100 °C. It is important to note that pure PLA cannot restore broken bonds, so that it is necessary to find structures which can take up large forces by deformation without full breaks. Here we report on the continuation of previous tests on 3D-printed cubes with different infill patterns and degrees, now investigating the influence of the orientation of the applied pressure on the recovery properties. We find that for the applied gyroid pattern, indentation on the front parallel to the layers gives the worst recovery due to nearly full layer separation, while indentation on the front perpendicular to the layers or diagonal gives significantly better results. Pressing from the top, either diagonal or parallel to an edge, interestingly leads to a different residual strain than pressing from front, with indentation on top always firstly leading to an expansion towards the indenter after the first few quasi-static load tests. To quantitatively evaluate these results, new measures are suggested which could be adopted by other groups working on shape-memory polymers. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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14 pages, 3759 KiB  
Article
Effects of Groove Sealing of the Posterior Occlusal Surface and Offset of the Internal Surface on the Internal Fit and Accuracy of Implant Placements Using 3D-Printed Surgical Guides: An In Vitro Study
by Jung-Hwa Lim, Enkhjargal Bayarsaikhan, Seung-Ho Shin, Na-Eun Nam, June-Sung Shim and Jong-Eun Kim
Polymers 2021, 13(8), 1236; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13081236 - 11 Apr 2021
Cited by 8 | Viewed by 2474
Abstract
This study evaluated the internal fit and the accuracy of the implant placement position in order to determine how the surface shape of the tooth and the offset influence the accuracy of the surgical guide. The acquired digital data were analyzed in three [...] Read more.
This study evaluated the internal fit and the accuracy of the implant placement position in order to determine how the surface shape of the tooth and the offset influence the accuracy of the surgical guide. The acquired digital data were analyzed in three dimensions using 3D inspection software. The obtained results confirmed that the internal fit was better in the groove sealing (GS) group (164.45 ± 28.34 μm) than the original shape (OS) group (204.07 ± 44.60 μm) (p < 0.001), and for an offset of 100 μm (157.50 ± 17.26 μm) than for offsets of 30 μm (206.48 ± 39.12 μm) and 60 μm (188.82 ± 48.77 μm) (p < 0.001). The accuracy of implant placement was better in the GS than OS group in terms of the entry (OS, 0.229 ± 0.092 mm; GS, 0.169 ± 0.061 mm; p < 0.001), apex (OS, 0.324 ± 0.149 mm; GS, 0.230 ± 0.124 mm; p < 0.001), and depth (OS, 0.041 ± 0.027 mm; GS, 0.025 ± 0.022 mm; p < 0.001). In addition, the entries (30 μm, 0.215 ± 0.044 mm; 60 μm, 0.172 ± 0.049 mm; 100 μm, 0.119 ± 0.050 mm; p < 0.001) were only affected by the amount of offset. These findings indicate that the accuracy of a surgical guide can be improved by directly sealing the groove of the tooth before manufacturing the surgical guide or setting the offset during the design process. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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17 pages, 4551 KiB  
Article
Effects of Postcuring Temperature on the Mechanical Properties and Biocompatibility of Three-Dimensional Printed Dental Resin Material
by Enkhjargal Bayarsaikhan, Jung-Hwa Lim, Seung-Ho Shin, Kyu-Hyung Park, Young-Bum Park, Jae-Hoon Lee and Jong-Eun Kim
Polymers 2021, 13(8), 1180; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13081180 - 07 Apr 2021
Cited by 55 | Viewed by 5447
Abstract
Three-dimensional (3D) printing is an attractive technology in dentistry. Acrylic-based 3D printed resin parts have to undergo postcuring processes to enhance their mechanical and biological properties, such as UV-light and thermal polymerization. However, no previous studies have revealed how the postcuring temperature influences [...] Read more.
Three-dimensional (3D) printing is an attractive technology in dentistry. Acrylic-based 3D printed resin parts have to undergo postcuring processes to enhance their mechanical and biological properties, such as UV-light and thermal polymerization. However, no previous studies have revealed how the postcuring temperature influences the biocompatibility of the produced parts. Therefore, we postprocessed 3D printed denture teeth resin under different postcuring temperatures (40, 60 and 80 °C) for different periods (15, 30, 60, 90 and 120 min), and evaluated their flexural properties, Vickers hardness, cell cytotoxicity, cell viability, and protein adsorption. In addition, confocal laser scanning was used to assess the condition of human gingival fibroblasts. It was found that increasing the postcuring temperature significantly improved the flexural strength and cell viability. The flexural strength and cell viability were 147.48 ± 5.82 MPa (mean ± standard deviation) and 89.51 ± 7.09%, respectively, in the group cured at 80 °C for 120 min, which were higher than the values in the 40 and 60 °C groups. The cell cytotoxicity increased in the 40 °C groups and for longer cultivation time. Confocal laser scanning revealed identifiable differences in the morphology of fibroblasts. This study has confirmed that the postcuring temperature influences the final mechanical and biological properties of 3D printed resin. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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17 pages, 64675 KiB  
Article
Manufacturing and Characterization of 3D Miniature Polymer Lattice Structures Using Fused Filament Fabrication
by Rafael Guerra Silva, María Josefina Torres, Jorge Zahr Viñuela and Arístides González Zamora
Polymers 2021, 13(4), 635; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13040635 - 20 Feb 2021
Cited by 17 | Viewed by 4296
Abstract
The potential of additive manufacturing to produce architected lattice structures is remarkable, but restrictions imposed by manufacturing processes lead to practical limits on the form and dimension of structures that can be produced. In the present work, the capabilities of fused filament fabrication [...] Read more.
The potential of additive manufacturing to produce architected lattice structures is remarkable, but restrictions imposed by manufacturing processes lead to practical limits on the form and dimension of structures that can be produced. In the present work, the capabilities of fused filament fabrication (FFF) to produce miniature lattices were explored, as they represent an inexpensive option for the production of polymer custom-made lattice structures. First, fused filament fabrication design guidelines were tested to assess their validity for miniature unit cells and lattice structures. The predictions were contrasted with the results of printing tests, showing some discrepancies between expected outcomes and resulting printed structures. It was possible to print functional 3D miniature open cell polymer lattice structures without support, even when some FFF guidelines were infringed, i.e., recommended minimum strut thickness and maximum overhang angle. Hence, a broad range of lattice structures with complex topologies are possible, beyond the cubic-type cell arrangements. Nevertheless, there are hard limits in 3D printing of miniature lattice structures. Strut thickness, length and orientation were identified as critical parameters in miniature lattice structures. Printed lattices that did not fully comply with FFF guidelines were capable of bearing compressive loads, even if surface quality and accuracy issues could not be fully resolved. Nevertheless, 3D printed FFF lattice structures could represent an improvement compared to other additive manufacturing processes, as they offer good control of cell geometry, and does not require additional post-processing. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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18 pages, 3977 KiB  
Article
An Overview on Personal Protective Equipment (PPE) Fabricated with Additive Manufacturing Technologies in the Era of COVID-19 Pandemic
by Szilard Rendeki, Balint Nagy, Matyas Bene, Attila Pentek, Luca Toth, Zalan Szanto, Roland Told and Peter Maroti
Polymers 2020, 12(11), 2703; https://0-doi-org.brum.beds.ac.uk/10.3390/polym12112703 - 16 Nov 2020
Cited by 44 | Viewed by 5300
Abstract
Different additive manufacturing technologies have proven effective and useful in remote medicine and emergency or disaster situations. The coronavirus disease 2019 (COVID-19) disease, caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus, has had a huge impact on our society, including [...] Read more.
Different additive manufacturing technologies have proven effective and useful in remote medicine and emergency or disaster situations. The coronavirus disease 2019 (COVID-19) disease, caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus, has had a huge impact on our society, including in relation to the continuous supply of personal protective equipment (PPE). The aim of the study is to give a detailed overview of 3D-printed PPE devices and provide practical information regarding the manufacturing and further design process, as well as describing the potential risks of using them. Open-source models of a half-face mask, safety goggles, and a face-protecting shield are evaluated, considering production time, material usage, and cost. Estimations have been performed with fused filament fabrication (FFF) and selective laser sintering (SLS) technology, highlighting the material characteristics of polylactic acid (PLA), polyamide, and a two-compound silicone. Spectrophotometry measurements of transparent PMMA samples were performed to determine their functionality as goggles or face mask parts. All the tests were carried out before and after the tetra-acetyl-ethylene-diamine (TAED)-based disinfection process. The results show that the disinfection has no significant effect on the mechanical and structural stability of the used polymers; therefore, 3D-printed PPE is reusable. For each device, recommendations and possible means of development are explained. The files of the modified models are provided. SLS and FFF additive manufacturing technology can be useful tools in PPE development and small-series production, but open-source models must be used with special care. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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Review

Jump to: Editorial, Research

15 pages, 1983 KiB  
Review
Applications of 3D-Printed PEEK via Fused Filament Fabrication: A Systematic Review
by Rupak Dua, Zuri Rashad, Joy Spears, Grace Dunn and Micaela Maxwell
Polymers 2021, 13(22), 4046; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13224046 - 22 Nov 2021
Cited by 57 | Viewed by 7215
Abstract
Polyether ether ketone (PEEK) is an organic polymer that has excellent mechanical, chemical properties and can be additively manufactured (3D-printed) with ease. The use of 3D-printed PEEK has been growing in many fields. This article systematically reviews the current status of 3D-printed PEEK [...] Read more.
Polyether ether ketone (PEEK) is an organic polymer that has excellent mechanical, chemical properties and can be additively manufactured (3D-printed) with ease. The use of 3D-printed PEEK has been growing in many fields. This article systematically reviews the current status of 3D-printed PEEK that has been used in various areas, including medical, chemical, aerospace, and electronics. A search of the use of 3D-printed PEEK articles published until September 2021 in various fields was performed using various databases. After reviewing the articles, and those which matched the inclusion criteria set for this systematic review, we found that the printing of PEEK is mainly performed by fused filament fabrication (FFF) or fused deposition modeling (FDM) printers. Based on the results of this systematic review, it was concluded that PEEK is a versatile material, and 3D-printed PEEK is finding applications in numerous industries. However, most of the applications are still in the research phase. Still, given how the research on PEEK is progressing and its additive manufacturing, it will soon be commercialized for many applications in numerous industries. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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20 pages, 2805 KiB  
Review
Polymer-Based Additive Manufacturing: Process Optimisation for Low-Cost Industrial Robotics Manufacture
by Kartikeya Walia, Ahmed Khan and Philip Breedon
Polymers 2021, 13(16), 2809; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13162809 - 21 Aug 2021
Cited by 10 | Viewed by 3774
Abstract
The robotics design process can be complex with potentially multiple design iterations. The use of 3D printing is ideal for rapid prototyping and has conventionally been utilised in concept development and for exploring different design parameters that are ultimately used to meet an [...] Read more.
The robotics design process can be complex with potentially multiple design iterations. The use of 3D printing is ideal for rapid prototyping and has conventionally been utilised in concept development and for exploring different design parameters that are ultimately used to meet an intended application or routine. During the initial stage of a robot development, exploiting 3D printing can provide design freedom, customisation and sustainability and ultimately lead to direct cost benefits. Traditionally, robot specifications are selected on the basis of being able to deliver a specific task. However, a robot that can be specified by design parameters linked to a distinctive task can be developed quickly, inexpensively, and with little overall risk utilising a 3D printing process. Numerous factors are inevitably important for the design of industrial robots using polymer-based additive manufacturing. However, with an extensive range of new polymer-based additive manufacturing techniques and materials, these could provide significant benefits for future robotics design and development. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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24 pages, 3081 KiB  
Review
Polymer 3D Printing Review: Materials, Process, and Design Strategies for Medical Applications
by Amit M. E. Arefin, Nava Raj Khatri, Nitin Kulkarni and Paul F. Egan
Polymers 2021, 13(9), 1499; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13091499 - 06 May 2021
Cited by 137 | Viewed by 32792
Abstract
Polymer 3D printing is an emerging technology with recent research translating towards increased use in industry, particularly in medical fields. Polymer printing is advantageous because it enables printing low-cost functional parts with diverse properties and capabilities. Here, we provide a review of recent [...] Read more.
Polymer 3D printing is an emerging technology with recent research translating towards increased use in industry, particularly in medical fields. Polymer printing is advantageous because it enables printing low-cost functional parts with diverse properties and capabilities. Here, we provide a review of recent research advances for polymer 3D printing by investigating research related to materials, processes, and design strategies for medical applications. Research in materials has led to the development of polymers with advantageous characteristics for mechanics and biocompatibility, with tuning of mechanical properties achieved by altering printing process parameters. Suitable polymer printing processes include extrusion, resin, and powder 3D printing, which enable directed material deposition for the design of advantageous and customized architectures. Design strategies, such as hierarchical distribution of materials, enable balancing of conflicting properties, such as mechanical and biological needs for tissue scaffolds. Further medical applications reviewed include safety equipment, dental implants, and drug delivery systems, with findings suggesting a need for improved design methods to navigate the complex decision space enabled by 3D printing. Further research across these areas will lead to continued improvement of 3D-printed design performance that is essential for advancing frontiers across engineering and medicine. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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20 pages, 2559 KiB  
Review
A Review of Vat Photopolymerization Technology: Materials, Applications, Challenges, and Future Trends of 3D Printing
by Marek Pagac, Jiri Hajnys, Quoc-Phu Ma, Lukas Jancar, Jan Jansa, Petr Stefek and Jakub Mesicek
Polymers 2021, 13(4), 598; https://0-doi-org.brum.beds.ac.uk/10.3390/polym13040598 - 17 Feb 2021
Cited by 291 | Viewed by 24514
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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Applications of 3D Printing for Polymers)
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