3D Printing of Functional Polymer Composites

A special issue of Polymers (ISSN 2073-4360). This special issue belongs to the section "Polymer Processing and Engineering".

Deadline for manuscript submissions: closed (30 September 2023) | Viewed by 21490

Special Issue Editor

1. Department of Russian composites, N.E. Bauman Moscow State Technical University, Moscow 105005, Russia
2. Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada
Interests: ionic polymers; poly(ionic liquid)s; polymer nanocomposites; nanoparticle alignment; stimuli-responsive polymers; 3D printing; polymer actuators

Special Issue Information

Dear Colleagues,

3D printing is a unique way of turning materials into finished products, which allows not only obtaining complex 3D architectures, but also achieving a micropatterned combination of different components, as well as control over the orientation of nanoparticles due to the shear force. Polymeric materials are firmly established in modern 3D production due to the ease of processing, light relative density, and tunable mechanical characteristics compared to inorganic analogues. The introduction of additional components into polymers, e.g., nanoparticles, nano- and microfibers, functional biomolecules, or other polymers, further expands the possible applications. In this Special Issue, we aim to collect recent academic achievements in 3D printing of functional polymer composites and covers various areas of their application, including but is not limited to the following topics:

  • 3D-printed stimuli-responsive polymers;
  • 3D-printed polymer actuators;
  • 3D-printed wound dressings;
  • 3D-printed cell scaffolds and tissues;
  • 3D-printed electroactive polymer composites.

Dr. Sofia M. Morozova
Guest Editor

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Keywords

  • 3D printing
  • polymer composites
  • stimuli-responsive polymers
  • extrusion printing
  • nanoparticles
  • hydrogels
  • actuators
  • electroactive polymers
  • bio applications
  • functional polymers
  • wound dressings
  • bio inks

Published Papers (13 papers)

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Research

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28 pages, 14411 KiB  
Article
Influence of Process Parameters in Material Extrusion on Product Properties Using the Example of the Electrical Resistivity of Conductive Polymer Composites
by Maximilian Nowka, Karl Hilbig, Lukas Schulze, Eggert Jung and Thomas Vietor
Polymers 2023, 15(22), 4452; https://doi.org/10.3390/polym15224452 - 17 Nov 2023
Viewed by 950
Abstract
Additive manufacturing of components using the material extrusion (MEX) of thermoplastics enables the integration of multiple materials into a single part. This can include functional structures, such as electrically conductive ones. The resulting functional structure properties depend on the process parameters along the [...] Read more.
Additive manufacturing of components using the material extrusion (MEX) of thermoplastics enables the integration of multiple materials into a single part. This can include functional structures, such as electrically conductive ones. The resulting functional structure properties depend on the process parameters along the entire manufacturing chain. The aim of this investigation is to determine the influence of process parameters in filament production and additive manufacturing on resistivity. Filament is produced from a commercially available composite of polylactide (PLA) with carbon nanotubes (CNT) and carbon black (CB), while the temperature profile and screw speed were varied. MEX specimens were produced using a full-factorial variation in extrusion temperature, layer height and deposition speed from the most and least conductive in-house-produced filament and the commercially available filament from the same composite. The results show that the temperature profile during filament production influences the resistivity. The commercially available filament has a lower conductivity than the in-house-produced filament, even though the starting feedstock is the same. The process parameters during filament production are the main factors influencing the resistivity of an additively manufactured structure. The MEX process parameters have a minimal influence on the resistivity of the used PLA/CNT/CB composite. Full article
(This article belongs to the Special Issue 3D Printing of Functional Polymer Composites)
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22 pages, 8291 KiB  
Article
Investigation of the Properties of Polyethylene and Ethylene-Vinyl Acetate Copolymer Blends for 3D Printing Applications
by Azamat Slonov, Ismel Musov, Azamat Zhansitov, Azamat Khashirov, Aslanbek Tlupov, Khasan Musov, Elena Rzhevskaya, Irina Fomicheva, Andrey Potapov and Svetlana Khashirova
Polymers 2023, 15(20), 4129; https://doi.org/10.3390/polym15204129 - 18 Oct 2023
Viewed by 920
Abstract
3D printing of polyolefins, such as polyethylene (PE) and polypropylene (PP), is of great practical interest due to the combination of high properties of these materials. However, the use of these materials in 3D printing is associated with many problems due to their [...] Read more.
3D printing of polyolefins, such as polyethylene (PE) and polypropylene (PP), is of great practical interest due to the combination of high properties of these materials. However, the use of these materials in 3D printing is associated with many problems due to their high rate of crystallization, which causes shrinkage and warpage of the printed object. In this regard, blends of PE and ethylene-vinyl acetate copolymer (EVA) of various compositions were investigated for 3D printing. It was found that with an increase in the concentration of EVA, an increase in the pseudoplastic effect and amorphization of PE occurs. It has been shown that with an increase in the EVA content, the degree of crystallinity of PE decreases slightly (by 11% at a content of 80% EVA); however, a significant decrease in the rate of crystallization of PE is observed (by 87.5% at the same EVA concentration). It was found that PE and EVA are completely compatible in the amorphous phase and partially compatible in the crystalline phase, which leads to a slight decrease in the melting point of PE. The introduction of EVA also leads to a significant increase in impact strength: the maximum value is achieved at a 50/50 ratio, which is five times the value of the initial PE and two times the value of the initial EVA. At the same time, it was revealed that EVA leads to a gradual decrease in the elastic modulus and strength of PE, the change of which generally obeys the additivity rule. The resulting printing filaments are characterized by a certain ovality due to their shrinkage, which decreases with increasing EVA content and reaches a minimum value at a PE/EVA ratio of 30/70. This composition also demonstrates the lowest shrinkage of the printed sample and higher processability during printing. Full article
(This article belongs to the Special Issue 3D Printing of Functional Polymer Composites)
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12 pages, 3754 KiB  
Article
An Innovative Biofunctional Composite Hydrogel with Enhanced Printability, Rheological Properties, and Structural Integrity for Cell Scaffold Applications
by Taufik Abdullah Mappa, Chung-Ming Liu, Chung-Chih Tseng, Muhammad Ruslin, Jui-Hung Cheng, Wen-Chien Lan, Bai-Hung Huang, Yung-Chieh Cho, Chia-Chien Hsieh, Hsin-Hui Kuo, Chen-Han Tsou and Yung-Kang Shen
Polymers 2023, 15(15), 3223; https://doi.org/10.3390/polym15153223 - 28 Jul 2023
Cited by 1 | Viewed by 905
Abstract
The present study was conducted to manipulate various biomaterials to find potential hydrogel formulations through three-dimensional (3D) bioprinting fabrication for tissue repair, reconstruction, or regeneration. The hydrogels were prepared using sodium alginate and gelatin combined with different concentrations of Pluronic F127 (6% (3 [...] Read more.
The present study was conducted to manipulate various biomaterials to find potential hydrogel formulations through three-dimensional (3D) bioprinting fabrication for tissue repair, reconstruction, or regeneration. The hydrogels were prepared using sodium alginate and gelatin combined with different concentrations of Pluronic F127 (6% (3 g), 8% (4 g), and 10% (5 g)) and were marked as AGF-6%, AGF-8%, and AGF-10%, respectively. The properties of the hydrogels were investigated using a contact angle goniometer, rheometer, and 3D bioprinter. In addition, the osteoblast-like cell line (MG-63) was used to evaluate the cell viability including hydrogels before and after 3D bioprinting. It was found that the ratio of contact angle was lowest at AGF-6%, and the rheological results were higher for all samples of AGF-6%, AGF-8%, and AGF-10% compared with the control sample. The printability indicated that the AGF-6% hydrogel possessed great potential in creating a cell scaffold with shape integrity. Moreover, the live/dead assay also presented the highest numbers of live cells before printing compared with after printing. However, the number of live cells on day 7 was higher than on day 1 before and after printing (** p < 0.01). Therefore, the combination of AGF-6% could be developed as a biofunctional hydrogel formulation for potential tissue regeneration applications. Full article
(This article belongs to the Special Issue 3D Printing of Functional Polymer Composites)
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15 pages, 7112 KiB  
Article
Three-Dimensional-Printed Polymeric Cores for Methane Hydrate Enhanced Growth
by Andrey Stoporev, Rail Kadyrov, Tatyana Adamova, Evgeny Statsenko, Thanh Hung Nguyen, Murtazali Yarakhmedov, Anton Semenov and Andrey Manakov
Polymers 2023, 15(10), 2312; https://doi.org/10.3390/polym15102312 - 15 May 2023
Cited by 4 | Viewed by 1243
Abstract
Polymeric models of the core prepared with a Raise3D Pro2 3D printer were employed for methane hydrate formation. Polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), carbon fiber reinforced polyamide-6 (UltraX), thermoplastic polyurethane (PolyFlex), and polycarbonate (ePC) were used for printing. Each plastic core [...] Read more.
Polymeric models of the core prepared with a Raise3D Pro2 3D printer were employed for methane hydrate formation. Polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), carbon fiber reinforced polyamide-6 (UltraX), thermoplastic polyurethane (PolyFlex), and polycarbonate (ePC) were used for printing. Each plastic core was rescanned using X-ray tomography to identify the effective porosity volumes. It was revealed that the polymer type matters in enhancing methane hydrate formation. All polymer cores except PolyFlex promoted the hydrate growth (up to complete water-to-hydrate conversion with PLA core). At the same time, changing the filling degree of the porous volume with water from partial to complete decreased the efficiency of hydrate growth by two times. Nevertheless, the polymer type variation allowed three main features: (1) managing the hydrate growth direction via water or gas preferential transfer through the effective porosity; (2) the blowing of hydrate crystals into the volume of water; and (3) the growth of hydrate arrays from the steel walls of the cell towards the polymer core due to defects in the hydrate crust, providing an additional contact between water and gas. These features are probably controlled by the hydrophobicity of the pore surface. The proper filament selection allows the hydrate formation mode to be set for specific process requirements. Full article
(This article belongs to the Special Issue 3D Printing of Functional Polymer Composites)
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11 pages, 3385 KiB  
Article
Comparative Investigations on Properties of Three Kinds of FDM 3D-Printed Natural Plant Powder/Poly(lactic acid) Biocomposites
by Dezhi Xu, Jianan Shi, Rui Qiu, Wen Lei and Wangwang Yu
Polymers 2023, 15(3), 557; https://doi.org/10.3390/polym15030557 - 21 Jan 2023
Cited by 7 | Viewed by 1613
Abstract
In order to further explore the feasibility of the application of the residue of Chinese herbal medicine in FDM 3D technology and enrich the kinds of printing materials, Astragalus residue powder(ARP)/poly(lactic acid) (PLA) biocomposite was FDM 3D-printed, meanwhile, two traditional biocomposites, i.e., wood [...] Read more.
In order to further explore the feasibility of the application of the residue of Chinese herbal medicine in FDM 3D technology and enrich the kinds of printing materials, Astragalus residue powder(ARP)/poly(lactic acid) (PLA) biocomposite was FDM 3D-printed, meanwhile, two traditional biocomposites, i.e., wood flour (WF)/PLA and rice straw powder (RSP)/PLA, were prepared by the same method, and the properties of the biocomposites were comparatively investigated. The results showed that, the tensile and flexural strengths of ARP/PLA were 28.33 MPa and 97.60 MPa, respectively, which were 2.85% and 10.89% smaller than those of WF/PLA, while 15.73% and 7.04% greater than those of RSP/PLA. WF/PLA showed typical brittle fracture characteristics, ARP/PLA and RSP/PLA both showed ductile fracture, but not obviously. Among the three kinds of biocomposites, ARP/PLA was the most thermally stable, followed by WF/PLA and RSP/PLA in turn. The incorporation of natural plant powder had no significant effect on the glassy transition, melting, and cold-crystallization behaviors of PLA, but the crystallinity of PLA could be increased from 0.3% to 2.0% and 1.9%, respectively, by adding ARP and WF. At 20 °C, the storage modulus of ARP/PLA, WF/PLA and RSP/PLA was 2759.4 MPa, 3361.3 MPa, and 2691.5 MPa, respectively, indicating that WF/PLA has the greatest stiffness, and the stiffness of RSP/PLA was the least. In addition to these, all the biocomposites were hydrophilic, the contact angle of the distilled water on the surface of ARP/PLA, WF/PLA or RSP/PLA was correspondingly 73.5°, 77.6° and 71.2°. Overall, it can be concluded that ARP/PLA has moderate strengths, stiffness and wettability, meanwhile, it is the most thermal stable among the three biocomposites, and can be processed at a temperature close to that of PLA. ARP/PLA is suitable as a new kind of feedstock material for FDM 3D printing. Full article
(This article belongs to the Special Issue 3D Printing of Functional Polymer Composites)
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17 pages, 2843 KiB  
Article
Modification of Commercial 3D Fused Deposition Modeling Printer for Extrusion Printing of Hydrogels
by Semyon I. Koltsov, Tatiana G. Statsenko and Sofia M. Morozova
Polymers 2022, 14(24), 5539; https://doi.org/10.3390/polym14245539 - 17 Dec 2022
Cited by 6 | Viewed by 2311
Abstract
In this paper, we report a simple modification of a commercially available printer with fused deposition modeling (FDM) technology for the implementation of extrusion printing of hydrogels. The main difference between an FDM printer and a gel-extrusion printer is their material propulsion system, [...] Read more.
In this paper, we report a simple modification of a commercially available printer with fused deposition modeling (FDM) technology for the implementation of extrusion printing of hydrogels. The main difference between an FDM printer and a gel-extrusion printer is their material propulsion system, which has to deal with ether a solid rod or liquid. By application of plastic 3D printing on an FDM printer, specific details, namely, the plunger system and parts of the gel supply system, were produced and combined with a modified printer. Two types of printing of polymer hydrogels were optimized: droplet and filament modes. The rheological ranges suitable for printing for each method were indicated, and the resolution of the samples obtained and the algorithms for creating g-code via Python scripts were given. We have shown the possibility of droplet printing of microspheres with a diameter of 100 microns and a distance between spheres of 200 microns, as well as filament printing of lines with a thickness of 300–2000 microns, which is appropriate accuracy in comparison with commercial printers. This method, in addition to scientific groups, will be especially promising for educational tasks (as a practical work for engineering students or for the introduction of 3D printing into school classes) and industrial groups, as a way to implement 3D extrusion printing of composite polymer hydrogels in a time- and cost-effective way. Full article
(This article belongs to the Special Issue 3D Printing of Functional Polymer Composites)
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11 pages, 3220 KiB  
Communication
New Building Blocks for Self-Healing Polymers
by Elena Platonova, Polina Ponomareva, Zalina Lokiaeva, Alexander Pavlov, Vladimir Nelyub and Alexander Polezhaev
Polymers 2022, 14(24), 5394; https://doi.org/10.3390/polym14245394 - 09 Dec 2022
Cited by 3 | Viewed by 1374
Abstract
The healing efficiency in self-healing materials is bound by the ability to form blends between the prepolymer and curing agent. One of the problems in the development of self-healing polymers is the reduced affinity of the bismaleimide curing agent for the elastomeric furan-containing [...] Read more.
The healing efficiency in self-healing materials is bound by the ability to form blends between the prepolymer and curing agent. One of the problems in the development of self-healing polymers is the reduced affinity of the bismaleimide curing agent for the elastomeric furan-containing matrix. Even when stoichiometric amounts of both components are applied, incompatibility of components can significantly reduce the effectiveness of self-healing, and lead to undesirable side effects, such as crystallization of the curing agent, in the thickness and on the surface. This is exactly what we have seen in the development of linear and cross-linked PUs using BMI as a hardener. In this work, we present a new series of the di- and tetrafuranic isocyanate-related ureas—promising curing agents for the development of polyurethanes-like self-healing materials via the Diels–Alder reaction. The commonly used isocyanates (4,4′-Methylene diphenyl diisocyanate, MDI; 2,4-Tolylene diisocyanate, TDI; and Hexamethylene diisocyanate, HDI) and furfurylamine, difurfurylamine, and furfuryl alcohol (derived from biorenewables) as furanic compounds were utilized for synthesis. The remendable polyurethane for testing was synthesized from a maleimide-terminated prepolymer and one of the T-series urea. Self-healing properties were investigated by thermal analysis. Molecular mass was determined by gel permeation chromatography. The properties of the new polymer were compared with polyurethane from a furan-terminated analog. Visual tests showed that the obtained material has thermally induced self-healing abilities. Resulting polyurethane (PU) has a rather low fusing point and thus may be used as potential material for Fused Deposition Modeling (FDM) 3D printing. Full article
(This article belongs to the Special Issue 3D Printing of Functional Polymer Composites)
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15 pages, 5620 KiB  
Article
Density Gradients, Cellular Structure and Thermal Conductivity of High-Density Polyethylene Foams by Different Amounts of Chemical Blowing Agent
by Juan Lobos, Saravana Prakash Thirumuruganandham and Miguel Angel Rodríguez-Pérez
Polymers 2022, 14(19), 4082; https://doi.org/10.3390/polym14194082 - 29 Sep 2022
Cited by 2 | Viewed by 2161
Abstract
LDPE (low-density polyethylene) foams were prepared using the improved compression moulding technique (ICM) with relative densities ranging from 0.3 to 0.7 and with different levels of chemical blowing agents (from 1% to 20%). The density gradients, cellular structure and thermal conductivity of the [...] Read more.
LDPE (low-density polyethylene) foams were prepared using the improved compression moulding technique (ICM) with relative densities ranging from 0.3 to 0.7 and with different levels of chemical blowing agents (from 1% to 20%). The density gradients, cellular structure and thermal conductivity of the foams were characterized. The density and amount of CBA used were found to have a significant effect on the cellular structure both at the mesoscale (density gradients) and at the microscale (different cell sizes and cell densities). In addition, the thermal conductivity of the samples is very sensitive to the local structure where the heat flux is located. The technique used to measure this property, the Transient Plane Source method (TPS), makes it possible to detect the presence of density gradients. A simple method for determining these gradients based on thermal conductivity data was developed. Full article
(This article belongs to the Special Issue 3D Printing of Functional Polymer Composites)
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16 pages, 72558 KiB  
Article
Physical Property of 3D-Printed N-Pointed Star-Shaped Outsole Prepared by FDM 3D Printer Using the Lightweight TPU
by Xiaokui Chen and Sunhee Lee
Polymers 2022, 14(15), 3189; https://doi.org/10.3390/polym14153189 - 04 Aug 2022
Viewed by 1743
Abstract
This investigation has shown the feasibility of modulation in physical properties for multiple outsole designs with 3-, 4-, and 6-pointed star-shaped patterns and various thicknesses for 5, 7.5, and 10 mm, which were fabricated with a FDM 3D printer using lightweight TPU filament, [...] Read more.
This investigation has shown the feasibility of modulation in physical properties for multiple outsole designs with 3-, 4-, and 6-pointed star-shaped patterns and various thicknesses for 5, 7.5, and 10 mm, which were fabricated with a FDM 3D printer using lightweight TPU filament, where the physical and foot pressure distribution properties were evaluated to confirm the best quality and comfort outsole. Through varying the structural pattern designs in combination with optimal 3D-printing parameters, the physical properties of the TPU LW-3, 4, and 6-PS outsoles were confirmed with enhanced properties along with increased thicknesses. In this study, the morphology images revealed a lower foaming state, a better-fused interlayer, and fewer microvoids in the TPU LW-3, 4, and 6-PS outsole, as the thickness developed, indicating enhanced density and rigidity. The best physical property was confirmed at LW 3-PS-10 with 0.706 specific gravity, 68.3 g weight, 0.232 μs static coefficient and 0.199 μk dynamic coefficient, 236% NSB abrasion, 127 mm3 DIN abrasion, 30% ball drop and 28% pendulum resilience, verifying the most high-quality, safe, and durable prototype. Regarding comfort, the 3-PS-10 also was regarded as comfortable concerning the wearable parts by virtue of its excellent physical properties, as well as its having the largest pressure area and the lower pressure force; meanwhile, the 4PS and 6PS also exhibited similar conditions for different thicknesses. Since not much distinct difference in pressure distribution compared to others was exhibited, it is suggested to explore optimization solutions to update the comfort of the footwear in future research. Full article
(This article belongs to the Special Issue 3D Printing of Functional Polymer Composites)
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13 pages, 3661 KiB  
Article
Lower Critical Solution Temperature Tuning and Swelling Behaviours of NVCL-Based Hydrogels for Potential 4D Printing Applications
by Shuo Zhuo, Elaine Halligan, Billy Shu Hieng Tie, Colette Breheny and Luke M. Geever
Polymers 2022, 14(15), 3155; https://doi.org/10.3390/polym14153155 - 02 Aug 2022
Cited by 6 | Viewed by 1529
Abstract
The phase transitions of poly (N-vinyl caprolactam) (PNVCL) hydrogels are currently under investigation as possible materials for biomedical applications thanks to their thermosensitive properties. This study aims to use the photopolymerisation process to simulate the 4D printing process. NVCL-based polymers with different thermal [...] Read more.
The phase transitions of poly (N-vinyl caprolactam) (PNVCL) hydrogels are currently under investigation as possible materials for biomedical applications thanks to their thermosensitive properties. This study aims to use the photopolymerisation process to simulate the 4D printing process. NVCL-based polymers with different thermal properties and swellability were prepared to explore the possibility of synthetic hydrogels being used for 4D printing. In this contribution, the thermal behaviours of novel photopolymerised NVCL-based hydrogels were analysed. The lower critical solution temperature (LCST) of the physically crosslinked gels was detected using differential scanning calorimetry (DSC), ultraviolet (UV) spectroscopy, and cloud point measurement. The chemical structure of the xerogels was characterised by means of Fourier transform infrared spectroscopy (FTIR). Pulsatile swelling studies indicated that the hydrogels had thermo-reversible properties. As a result, the effect of varying the macromolecular monomer concentration was apparent. The phase transition temperature is increased when different concentrations of hydrophilic monomers are incorporated. The transition temperature of the hydrogels may allow for excellent flexibility in tailoring transition for specific applications, while the swelling and deswelling behaviour of the gels is strongly temperature- and monomer feed ratio-dependent. Full article
(This article belongs to the Special Issue 3D Printing of Functional Polymer Composites)
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16 pages, 2352 KiB  
Article
Printable Alginate Hydrogels with Embedded Network of Halloysite Nanotubes: Effect of Polymer Cross-Linking on Rheological Properties and Microstructure
by Svetlana A. Glukhova, Vyacheslav S. Molchanov, Boris V. Lokshin, Andrei V. Rogachev, Alexey A. Tsarenko, Timofey D. Patsaev, Roman A. Kamyshinsky and Olga E. Philippova
Polymers 2021, 13(23), 4130; https://doi.org/10.3390/polym13234130 - 26 Nov 2021
Cited by 16 | Viewed by 2230
Abstract
Rapidly growing 3D printing of hydrogels requires network materials which combine enhanced mechanical properties and printability. One of the most promising approaches to strengthen the hydrogels consists of the incorporation of inorganic fillers. In this paper, the rheological properties important for 3D printability [...] Read more.
Rapidly growing 3D printing of hydrogels requires network materials which combine enhanced mechanical properties and printability. One of the most promising approaches to strengthen the hydrogels consists of the incorporation of inorganic fillers. In this paper, the rheological properties important for 3D printability were studied for nanocomposite hydrogels based on a rigid network of percolating halloysite nanotubes embedded in a soft alginate network cross-linked by calcium ions. Particular attention was paid to the effect of polymer cross-linking on these properties. It was revealed that the system possessed a pronounced shear-thinning behavior accompanied by a viscosity drop of 4–5 orders of magnitude. The polymer cross-links enhanced the shear-thinning properties and accelerated the viscosity recovery at rest so that the system could regain 96% of viscosity in only 18 s. Increasing the cross-linking of the soft network also enhanced the storage modulus of the nanocomposite system by up to 2 kPa. Through SAXS data, it was shown that at cross-linking, the junction zones consisting of fragments of two laterally aligned polymer chains were formed, which should have provided additional strength to the hydrogel. At the same time, the cross-linking of the soft network only slightly affected the yield stress, which seemed to be mainly determined by the rigid percolation network of nanotubes and reached 327 Pa. These properties make the alginate/halloysite hydrogels very promising for 3D printing, in particular, for biomedical purposes taking into account the natural origin, low toxicity, and good biocompatibility of both components. Full article
(This article belongs to the Special Issue 3D Printing of Functional Polymer Composites)
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9 pages, 2184 KiB  
Article
3D-Printed Porous Magnetic Carbon Materials Derived from Metal–Organic Frameworks
by Anton I. Cherevko, Igor A. Nikovskiy, Yulia V. Nelyubina, Kirill M. Skupov, Nikolay N. Efimov and Valentin V. Novikov
Polymers 2021, 13(22), 3881; https://doi.org/10.3390/polym13223881 - 10 Nov 2021
Cited by 5 | Viewed by 2141
Abstract
Here we report new porous carbon materials obtained by 3D printing from photopolymer compositions with zinc- and nickel-based metal–organic frameworks, ZIF-8 and Ni-BTC, followed by high-temperature pyrolysis. The pyrolyzed materials that retain the shapes of complex objects contain pores, which were produced by [...] Read more.
Here we report new porous carbon materials obtained by 3D printing from photopolymer compositions with zinc- and nickel-based metal–organic frameworks, ZIF-8 and Ni-BTC, followed by high-temperature pyrolysis. The pyrolyzed materials that retain the shapes of complex objects contain pores, which were produced by boiling zinc and magnetic nickel particles. The two thus provided functionalities—large specific surface area and ferromagnetism—that pave the way towards creating heterogenous catalysts that can be easily removed from reaction mixtures in industrial catalytic processes. Full article
(This article belongs to the Special Issue 3D Printing of Functional Polymer Composites)
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Review

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12 pages, 1396 KiB  
Review
Recent Progress of 3D Printing of Polymer Electrolyte Membrane-Based Fuel Cells for Clean Energy Generation
by Sergey S. Golubkov and Sofia M. Morozova
Polymers 2023, 15(23), 4553; https://doi.org/10.3390/polym15234553 - 28 Nov 2023
Viewed by 1203
Abstract
This review summarizes recent advances in the application of 3D printing (additive manufacturing) for the fabrication of various components of hydrogen fuel cells with a polymer electrolyte membrane (HFC-PEMs). This type of fuel cell is an example of green renewable energy, but its [...] Read more.
This review summarizes recent advances in the application of 3D printing (additive manufacturing) for the fabrication of various components of hydrogen fuel cells with a polymer electrolyte membrane (HFC-PEMs). This type of fuel cell is an example of green renewable energy, but its active implementation into the real industry is fraught with a number of problems, including rapid degradation and low efficiency. The application of 3D printing is promising for improvement in HFC-PEM performance due to the possibility of creating complex geometric shapes, the exact location of components on the substrate, as well as the low-cost and simplicity of the process. This review examines the use of various 3D printing techniques, such as inkjet printing, fused deposition modeling (FDM) and stereolithography, for the production/modification of electrodes, gas diffusion and catalyst layers, as well as bipolar plates. In conclusion, the challenges and possible solutions of the identified drawbacks for further development in this field of research are discussed. It is expected that this review article will benefit both representatives of applied science interested in specific engineering solutions and fundamental science aimed at studying the processes occurring in the fuel cell. Full article
(This article belongs to the Special Issue 3D Printing of Functional Polymer Composites)
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