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13 pages, 3350 KiB

Open AccessArticle

Mg-Doped PLA Composite as a Potential Material for Tissue Engineering—Synthesis, Characterization, and Additive Manufacturing

by Fawad Ali, Ans Al Rashid, Sumama Nuthana Kalva and Muammer Koç

Materials 2023, 16(19), 6506; https://0-doi-org.brum.beds.ac.uk/10.3390/ma16196506 - 30 Sep 2023

Cited by 2 | Viewed by 1174

Abstract

Magnesium (Mg)/Polylactic acid (PLA) composites are promising materials for bone regeneration and tissue engineering applications. PLA is a biodegradable and biocompatible polymer that can be easily processed into various shapes and structures, such as scaffolds, films, and fibers, but has low biodegradability. Mg [...] Read more.

Magnesium (Mg)/Polylactic acid (PLA) composites are promising materials for bone regeneration and tissue engineering applications. PLA is a biodegradable and biocompatible polymer that can be easily processed into various shapes and structures, such as scaffolds, films, and fibers, but has low biodegradability. Mg is a biocompatible metal that has been proven to have good biodegradability and osteoconductivity, which makes it suitable for bone tissue engineering. In this study, we prepared and characterized a Mg/PLA composite as a potential material for direct ink writing (DIW) in 3D printing. The results showed that the addition of Mg has a significant impact on PLA’s thermal and structural properties and has also significantly increased the degradation of PLA. XRD was used to determine the degree of crystallinity in the PLA/Mg composite, which provides insight into its thermal stability and degradation behavior. The crystallization temperature of PLA increased from 168 to 172 °C for a 15 wt% Mg incorporation, and the melting temperature reduced from 333 °C to 285 °C. The surface morphology and composition of these films were analyzed with SEM. The films with 5 wt% of Mg particles displayed the best-ordered honeycomb structure in their film form. Such structures are considered to affect the mechanical, biological and heat/mass transfer properties of the Mg/PLA composites and products. Finally, the composite ink was used as a feed for direct ink writing in 3D printing, and the preliminary 3D printing experiments were successful in resulting in dimensionally and structurally integral scaffold samples. The shape fidelity was not very good, and some research is needed to improve the rheological properties of the ink for DIW 3D printing. Full article

(This article belongs to the Special Issue 3D Printing and Additive Manufacturing of Polymer and Composites)

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20 pages, 18241 KiB

Open AccessArticle

Investigation on Filaments for 3D Printing of Nasal Septum Cartilage Implant

by Przemysław Gnatowski, Karolina Gwizdała, Agnieszka Kurdyn, Andrzej Skorek, Ewa Augustin and Justyna Kucińska-Lipka

Materials 2023, 16(9), 3534; https://0-doi-org.brum.beds.ac.uk/10.3390/ma16093534 - 5 May 2023

Cited by 2 | Viewed by 1660

Abstract

Septoplasty is a widely used method in treating deviated septum. Although it is successfully implemented, there are problems with excessive bleeding, septal perforation, or infections. The use of anatomically shaped implants could help overcome these problems. This paper focuses on assessing the possibility [...] Read more.

Septoplasty is a widely used method in treating deviated septum. Although it is successfully implemented, there are problems with excessive bleeding, septal perforation, or infections. The use of anatomically shaped implants could help overcome these problems. This paper focuses on assessing the possibility of the usage of a nasal septum cartilage implant 3D printed from various market-available filaments. Five different types of laments were used, two of which claim to be suitable for medical use. A combination of modeling, mechanical (bending, compression), structural (FTIR), thermal (DSC, MFR), surface (contact angle), microscopic (optical), degradation (2 M HCl, 5 M NaOH, and 0.01 M PBS), printability, and cell viability (MTT) analyses allowed us to assess the suitability of materials for manufacturing implants. Bioflex had the most applicable properties among the tested materials, but despite the overall good performance, cell viability studies showed toxicity of the material in MTT test. The results of the study show that selected filaments were not suitable for nasal cartilage implants. The poor cell viability of Bioflex could be improved by surface modification. Further research on biocompatible elastic materials for 3D printing is needed either by the synthesis of new materials or by modifying existing ones. Full article

(This article belongs to the Special Issue 3D Printing and Additive Manufacturing of Polymer and Composites)

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13 pages, 1713 KiB

Open AccessArticle

Towards Highly Efficient, Additively Manufactured Passive Vibration Eliminators for Mechanical Systems

by Izabela Irska, Grzegorz Kramek, Karol Miądlicki, Paweł Dunaj, Stefan Berczyński and Elżbieta Piesowicz

Materials 2023, 16(3), 1250; https://0-doi-org.brum.beds.ac.uk/10.3390/ma16031250 - 1 Feb 2023

Viewed by 1289

Abstract

Structural damping largely determines the dynamic properties of mechanical structures, especially those whose functioning is accompanied by time-varying loads. These loads may cause vibrations of a different nature, which adversely affects the functionality of the structure. Therefore, many studies have been carried out [...] Read more.

Structural damping largely determines the dynamic properties of mechanical structures, especially those whose functioning is accompanied by time-varying loads. These loads may cause vibrations of a different nature, which adversely affects the functionality of the structure. Therefore, many studies have been carried out on vibration reduction methods over the last few years. Among them, the passive vibration damping method, wherein a suitable polymer system with appropriate viscoelastic properties is used, emerges as one of the simplest and most effective methods. In this view, a novel approach to conduct passive elimination of vibrations, consisting of covering elements of structures with low dynamic stiffness with polymeric pads, was developed. Herein, polymer covers were manufactured via fused filament fabrication technology (3D printing) and were joined to the structure by means of a press connection. Current work was focused on determining the damping properties of chosen polymeric materials, including thermoplastic elastomers (TPE). All investigated materials were characterized by means of differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), and mechanical properties (tensile test and Shore hardness). Lastly, the damping ability of pads made from different types of polymers were evaluated by means of dynamic tests. Full article

(This article belongs to the Special Issue 3D Printing and Additive Manufacturing of Polymer and Composites)

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15 pages, 2943 KiB

Open AccessEditor’s ChoiceArticle

Improvement of the Thermal Conductivity and Mechanical Properties of 3D-Printed Polyurethane Composites by Incorporating Hydroxylated Boron Nitride Functional Fillers

by Kai-Han Su, Cherng-Yuh Su, Wei-Ling Shih and Fang-Ting Lee

Materials 2023, 16(1), 356; https://0-doi-org.brum.beds.ac.uk/10.3390/ma16010356 - 30 Dec 2022

Cited by 6 | Viewed by 2648

Abstract

Recently, the use of fused deposition modeling (FDM) in the three-dimensional (3D) printing of thermal interface materials (TIMs) has garnered increasing attention. Because fillers orient themselves along the direction of the melt flow during printing, this method could effectively enhance the thermal conductivity [...] Read more.

Recently, the use of fused deposition modeling (FDM) in the three-dimensional (3D) printing of thermal interface materials (TIMs) has garnered increasing attention. Because fillers orient themselves along the direction of the melt flow during printing, this method could effectively enhance the thermal conductivity of existing composite materials. However, the poor compatibility and intensive aggregation of h-BN fillers in polymer composites are still detrimental to their practical application in thermally conductive materials. In this study, hydroxyl-functionalized boron nitride (OH-BN) particles were prepared by chemical modification and ultrasonic-assisted liquid-phase exfoliation to explore their impact on the surface compatibility, mechanical properties and the final anisotropic thermal conductivity of thermoplastic polyurethane (TPU) composites fabricated by FDM printing. The results show that the surface-functionalized OH-BN fillers are homogeneously dispersed in the TPU matrix via hydrogen bonding interactions, which improve the interfacial adhesion between the filler and matrix. For the same concentration of loaded filler, the OH-BN/TPU composites exhibit better mechanical properties and thermal conductivities than composites incorporating non-modified h-BN. These composites also show higher heat conduction along the stand-vertical direction, while simultaneously exhibiting a low dielectric constant and dielectric loss. This work therefore provides a possible strategy for the fabrication of thermal management polymers using 3D-printing methods. Full article

(This article belongs to the Special Issue 3D Printing and Additive Manufacturing of Polymer and Composites)

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13 pages, 3868 KiB

Open AccessEditor’s ChoiceArticle

Microstructural Characterization and Property of Carbon Fiber Reinforced High-Density Polyethylene Composites Fabricated by Fused Deposition Modeling

by Partha Pratim Pandit, Chang Liu, Scott Iacono, Giancarlo Corti and Yingbin Hu

Materials 2023, 16(1), 180; https://0-doi-org.brum.beds.ac.uk/10.3390/ma16010180 - 25 Dec 2022

Cited by 3 | Viewed by 2300

Abstract

As a promising industrial thermoplastic polymer material, high-density polyethylene (HDPE) possesses distinct properties of ease to process, good biocompatibility, high recyclability, etc. and has been widely used to make packaging, prostheses and implants, and liquid-permeable membranes. Traditional manufacturing processes for HDPE, including injection [...] Read more.

As a promising industrial thermoplastic polymer material, high-density polyethylene (HDPE) possesses distinct properties of ease to process, good biocompatibility, high recyclability, etc. and has been widely used to make packaging, prostheses and implants, and liquid-permeable membranes. Traditional manufacturing processes for HDPE, including injection molding, thermoforming, and rotational molding, require molds or post processing. In addition, part shapes are highly restricted., Thus, fused deposition modeling (FDM) is introduced to process HDPE materials to take advantage of FDM’s free of design, no mold requirement, ease and low cost of processing. To improve the mechanical properties (such as stiffness and strength) and thermal resistance of HDPE, carbon fiber (CF) was incorporated into HDPE, and CF-reinforced HDPE composites were successfully fabricated using FDM process. In addition, the effects of CF content on surface quality, microstructure characterizations, tensile properties, dynamic mechanical properties, and thermal properties have been investigated. Experimental results show that an appropriate CF content addition is beneficial for improving surface quality, and mechanical and thermal properties. Full article

(This article belongs to the Special Issue 3D Printing and Additive Manufacturing of Polymer and Composites)

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20 pages, 10130 KiB

Open AccessEditor’s ChoiceArticle

Open Hole Tension of 3D Printed Aligned Discontinuous Composites

by Narongkorn Krajangsawasdi, Ian Hamerton, Benjamin K. S. Woods, Dmitry S. Ivanov and Marco L. Longana

Materials 2022, 15(23), 8698; https://0-doi-org.brum.beds.ac.uk/10.3390/ma15238698 - 6 Dec 2022

Cited by 5 | Viewed by 1945

Abstract

This paper explores the use of Discontinuous Aligned Fibre Filament (DcAFF), a novel discontinuous fibre reinforced thermoplastic filament for 3D printing, to produce structural complex parts. Compared to conventional composite manufacturing, 3D printing has great potential in steering fibres around small structural features. [...] Read more.

This paper explores the use of Discontinuous Aligned Fibre Filament (DcAFF), a novel discontinuous fibre reinforced thermoplastic filament for 3D printing, to produce structural complex parts. Compared to conventional composite manufacturing, 3D printing has great potential in steering fibres around small structural features. In this current study, the initial thin carbon fibre (CF)-poly(L-lactic acid) (PLA) tape, produced with the High Performance Discontinuous Fibre (HiPerDiF) technology, is now reshaped into a circular cross-section filament, the DcAFF, using a bespoke machine designed to be scalable to high production rates rather than using a labour-intensive manual moulding method as in previous work. The filaments are then fed to a general-purpose 3D printer. Tensile and open-hole tensile tests were considered in this paper for mechanical and processability of DcAFF. The 3D printed specimens fabricated with the DcAFF show superior tensile properties compared to other PLA-based 3D printed composites, even those containing continuous fibres. Curvilinear open-hole tensile test samples were fabricated to explore the processability and performances of such material in complex shapes. The mechanical performance of the produced specimens was benchmarked against conventionally laid-up specimens with a cut hole. Although the steered specimens produced have lower strength than the fully consolidated samples, the raster generated by the printing path has turned the failure mechanism of the composite from brittle to ductile. Full article

(This article belongs to the Special Issue 3D Printing and Additive Manufacturing of Polymer and Composites)

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11 pages, 3429 KiB

Open AccessArticle

Investigation of Tensile Properties of Different Infill Pattern Structures of 3D-Printed PLA Polymers: Analysis and Validation Using Finite Element Analysis in ANSYS

by S. Ganeshkumar, S. Dharani Kumar, U. Magarajan, S. Rajkumar, B. Arulmurugan, Shubham Sharma, Changhe Li, R. A. Ilyas and Mohamed Fathy Badran

Materials 2022, 15(15), 5142; https://0-doi-org.brum.beds.ac.uk/10.3390/ma15155142 - 25 Jul 2022

Cited by 22 | Viewed by 5381

Abstract

The advancement of 3D-printing technology has ushered in a new era in the production of machine components, building materials, prototypes, and so on. In 3D-printing techniques, the infill reduces the amount of material used, thereby reducing the printing time and sustaining the aesthetics [...] Read more.

The advancement of 3D-printing technology has ushered in a new era in the production of machine components, building materials, prototypes, and so on. In 3D-printing techniques, the infill reduces the amount of material used, thereby reducing the printing time and sustaining the aesthetics of the products. Infill patterns play a significant role in the property of the material. In this research, the mechanical properties of specimens are investigated for gyroid, rhombile, circular, truncated octahedron, and honeycomb infill structures (hexagonal). Additionally, the tensile properties of PLA 3D-printed objects concerning their infill pattern are demonstrated. The specimens were prepared with various infill patterns to determine the tensile properties. The fracture of the specimen was simulated and the maximum yield strengths for different infill structures and infill densities were determined. The results show the hexagonal pattern of infill holds remarkable mechanical properties compared with the other infill structures. Through the variation of infill density, the desired tensile strength of PLA can be obtained based on the applications and the optimal weight of the printed parts. Full article

(This article belongs to the Special Issue 3D Printing and Additive Manufacturing of Polymer and Composites)

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Review

Jump to: Research

16 pages, 5094 KiB

Open AccessFeature PaperReview

A Review of Natural Fiber-Based Filaments for 3D Printing: Filament Fabrication and Characterization

by Mohd Nazri Ahmad, Mohamad Ridzwan Ishak, Mastura Mohammad Taha, Faizal Mustapha and Zulkiflle Leman

Materials 2023, 16(11), 4052; https://0-doi-org.brum.beds.ac.uk/10.3390/ma16114052 - 29 May 2023

Cited by 16 | Viewed by 4387

Abstract

Today, additive manufacturing (AM) is the most recent technology used to produce detailed and complexly built parts for a variety of applications. The most emphasis has been given to fused deposition modeling (FDM) in the development and manufacturing fields. Natural fibers have received [...] Read more.

Today, additive manufacturing (AM) is the most recent technology used to produce detailed and complexly built parts for a variety of applications. The most emphasis has been given to fused deposition modeling (FDM) in the development and manufacturing fields. Natural fibers have received attention in the area of 3D printing to be employed as bio-filters with thermoplastics, which have prompted an effort for more ecologically acceptable methods of manufacturing. The development of natural fiber composite filaments for FDM requires meticulous methods and in-depth knowledge of the properties of natural fibers and their matrices. Thus, this paper reviews natural fiber-based 3D printing filaments. It covers the fabrication method and characterization of thermoplastic materials blended with natural fiber-produced wire filament. The characterization of wire filament includes the mechanical properties, dimension stability, morphological study, and surface quality. There is also a discussion of the difficulties in developing a natural fiber composite filament. Last but not least, the prospects of natural fiber-based filaments for FDM 3D printing are also discussed. It is hoped that, after reading this article, readers will have enough knowledge regarding how natural fiber composite filament for FDM is created. Full article

(This article belongs to the Special Issue 3D Printing and Additive Manufacturing of Polymer and Composites)

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