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Mihelčič M, Oseli A, Rojac T, Slemenik Perše L. Surface Modification of Copper-Based Flakes for Conductive Polymer Composites. Polymers (Basel) 2024; 16:1620. [PMID: 38931970 PMCID: PMC11207403 DOI: 10.3390/polym16121620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Revised: 05/28/2024] [Accepted: 06/06/2024] [Indexed: 06/28/2024] Open
Abstract
The physical properties as well as thermal and electrical stability of copper particles can be improved by surface protection, which mainly depends on the coating material. Our study was, therefore, focused on the rheological, thermal, mechanical and electrical characterization of polymer composites by comparing uncoated (Cu), silver-coated (Cu@Ag) and silica-coated (Cu@Si) copper flakes in low-density polyethylene at various volume concentrations (up to 40%). Interactions among particles were investigated by rheological properties, as these indicate network formation (geometrical entanglement), which is important for mechanical reinforcement as well as establishing an electric pathway (electrical percolation). The results showed that geometrical and electrical percolation were the same for Cu and Cu@Si, ~15%, while, surprisingly, Cu@Ag exhibited much lower percolation, ~7.5%, indicating the fusion of the Ag coating material, which also decreased crystal growth (degree of crystallinity). Furthermore, the magnitude of the rheological and mechanical response remained the same for all investigated materials, indicating that the coating materials do not provide any load transfer capabilities. However, they profoundly affect electron transfer, in that, Cu@Ag exhibited superior conductivity (74.4 S/m) compared to Cu (1.7 × 10-4 S/m) and Cu@Si (1.5 × 10-10 S/m). The results obtained are important for the design of advanced polymer composites for various applications, particularly in electronics where enhanced electrical conductivity is desired.
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Affiliation(s)
- Mohor Mihelčič
- Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva Ulica 6, 1000 Ljubljana, Slovenia; (M.M.); (A.O.)
| | - Alen Oseli
- Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva Ulica 6, 1000 Ljubljana, Slovenia; (M.M.); (A.O.)
| | - Tadej Rojac
- Electronic Ceramics Department, Jozef Stefan Institute, Jamova Ulica 39, 1000 Ljubljana, Slovenia;
| | - Lidija Slemenik Perše
- Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva Ulica 6, 1000 Ljubljana, Slovenia; (M.M.); (A.O.)
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2
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Črešnar KP, Plohl O, Zemljič LF. Functionalised Fibres as a Coupling Reinforcement Agent in Recycled Polymer Composites. MATERIALS (BASEL, SWITZERLAND) 2024; 17:2739. [PMID: 38894002 PMCID: PMC11174083 DOI: 10.3390/ma17112739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 05/22/2024] [Accepted: 05/27/2024] [Indexed: 06/21/2024]
Abstract
This study addresses the structure-property relationship within the green concept of wood fibres with cellulose nanofibre functionalised composites (nW-PPr) containing recycled plastic polyolefins, in particular, polypropylene (PP-r). It focuses especially on the challenges posed by nanoscience in relation to wood fibres (WF) and explores possible changes in the thermal properties, crystallinity, morphology, and mechanical properties. In a two-step methodology, wood fibres (50% wt%) were first functionalised with nanocellulose (nC; 1-9 wt%) and then, secondly, processed into composites using an extrusion process. The surface modification of nC improves its compatibility with the polymer matrix, resulting in improved adhesion, mechanical properties, and inherent biodegradability. The effects of the functionalised WF on the recycled polymer composites were investigated systematically and included analyses of the structure, crystallisation, morphology, and surface properties, as well as thermal and mechanical properties. Using a comprehensive range of techniques, including X-ray diffraction (XRD), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), zeta potential measurements, and dynamic mechanical analysis (DMA), this study aims to unravel the intricate interplay of factors affecting the performance and properties of the developed nanocellulose-functionalised wood fibre-polymer composites. The interfacial adhesion of the nW-PPr polymer composites, crystallisation process, and surface properties was improved due to the formation of an H-bond between the nW coupling agent and neat PP-r. In addition, the role of nW (1.0 wt%) as a nucleating agent resulted in increased crystallinity, or, on the other hand, promoted the interfacial interaction with the highest amount (3.0% wt%, 9.0% wt%) of nW in the PP-r preferentially between the nW and neat PP-r, and also postponed the crystallisation temperature. The changes in the isoelectric point of the nW-PPr polymer composites compared to the neat PP-r polymer indicate the acid content of the polymer composite and, consequently, the final surface morphology. Finally, the higher storage modulus of the composites compared to neat r-PP shows a dependence on improved crystallinity, morphology, and adhesion. It was clear that the results of this study contribute to a better understanding of sustainable materials and can drive the development of environmentally friendly composites applied in packaging.
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Affiliation(s)
- Klementina Pušnik Črešnar
- Faculty of Mechanical Engineering, University of Maribor, 2000 Maribor, Slovenia; (O.P.); (L.F.Z.)
- Faculty of Chemistry and Chemical Engineering, University of Maribor, 2000 Maribor, Slovenia
| | - Olivija Plohl
- Faculty of Mechanical Engineering, University of Maribor, 2000 Maribor, Slovenia; (O.P.); (L.F.Z.)
| | - Lidija Fras Zemljič
- Faculty of Mechanical Engineering, University of Maribor, 2000 Maribor, Slovenia; (O.P.); (L.F.Z.)
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3
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Latko-Durałek P, Rzempołuch J, Staniszewska M, Rosłoniec K, Bil M, Kozera R, Boczkowska A. The Antifungal Fibers of Polyamide 12 Containing Silver and Metal Oxides. MATERIALS (BASEL, SWITZERLAND) 2023; 16:5837. [PMID: 37687530 PMCID: PMC10488922 DOI: 10.3390/ma16175837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 08/15/2023] [Accepted: 08/17/2023] [Indexed: 09/10/2023]
Abstract
The textile market is a vast industry that utilizes antimicrobial polymeric materials, including various types of fabrics, for medical and personal protection applications. Therefore, this study focused on examining four types of antimicrobial fillers, namely, metal oxides (zinc, titanium, copper) and nanosilver, as fillers in Polyamide 12 fibers. These fillers can be applied in the knitting or weaving processes to obtain woven polymeric fabrics for medical applications. The production of the fibers in this study involved a two-step approach: twin-screw extrusion and melt spinning. The resulting fibers were then characterized for their thermal properties (TGA, DSC), mechanical performance (tensile test, DMA), and antifungal activity. The findings of the study indicated that all of the fibers modified with fillers kill Candida albicans. However, the fibers containing a combination of metal oxides and silver showed significantly higher antifungal activity (reduction rate % R = 86) compared to the fibers with only a mixture of metal oxides (% R = 21). Furthermore, the inclusion of metal oxides and nanosilver in the Polyamide 12 matrix hindered the formation of the crystal phase and decreased slightly the thermal stability and mechanical properties, especially for the composites with nanosilver. It was attributed to their worse dispersion and the presence of agglomerates.
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Affiliation(s)
- Paulina Latko-Durałek
- Faculty of Materials Science and Engineering, Warsaw University of Technology, Wołoska 141 Street, 02-507 Warsaw, Poland; (J.R.); (R.K.); (A.B.)
| | - Józef Rzempołuch
- Faculty of Materials Science and Engineering, Warsaw University of Technology, Wołoska 141 Street, 02-507 Warsaw, Poland; (J.R.); (R.K.); (A.B.)
| | - Monika Staniszewska
- Centre for Advanced Materials and Technologies CEZAMAT, Warsaw University of Technology, Poleczki 19 Street, 02-822 Warsaw, Poland; (M.S.); (K.R.); (M.B.)
| | - Karina Rosłoniec
- Centre for Advanced Materials and Technologies CEZAMAT, Warsaw University of Technology, Poleczki 19 Street, 02-822 Warsaw, Poland; (M.S.); (K.R.); (M.B.)
| | - Monika Bil
- Centre for Advanced Materials and Technologies CEZAMAT, Warsaw University of Technology, Poleczki 19 Street, 02-822 Warsaw, Poland; (M.S.); (K.R.); (M.B.)
| | - Rafał Kozera
- Faculty of Materials Science and Engineering, Warsaw University of Technology, Wołoska 141 Street, 02-507 Warsaw, Poland; (J.R.); (R.K.); (A.B.)
| | - Anna Boczkowska
- Faculty of Materials Science and Engineering, Warsaw University of Technology, Wołoska 141 Street, 02-507 Warsaw, Poland; (J.R.); (R.K.); (A.B.)
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Haque ANMA, Naebe M. Material Extrusion of Wool Waste/Polycaprolactone with Improved Tensile Strength and Biodegradation. Polymers (Basel) 2023; 15:3439. [PMID: 37631496 PMCID: PMC10459355 DOI: 10.3390/polym15163439] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 08/02/2023] [Accepted: 08/16/2023] [Indexed: 08/27/2023] Open
Abstract
Additive manufacturing (AM) through material extrusion (MEX) is becoming increasingly popular worldwide due to its simple, sustainable and safe technique of material preparation, with minimal waste generation. This user-friendly technique is currently extensively used in diverse industries and household applications. Recently, there has been increasing attention on polycaprolactone (PCL)-based composites in MEX due to their improved biodegradability. These composites can be printed at a lower temperature, making them more energy efficient compared to commercial filaments such as acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA). Although wool is the leading protein fibre in the world and can be more compatible with PCL due to its inherent hydrophobicity, the suitability of MEX using a wool/PCL combination has not been reported previously. In the current study, waste wool/PCL composite parts were printed using the MEX technique, and rheology, thermal and tensile properties, and morphology were analysed. The impact of wool loading (10% and 20%) was investigated in relation to different filling patterns (concentric, rectilinear and gyroid). Furthermore, the impact of fibre fineness on the final material produced through MEX was investigated for the first time using two types of wool fibres with diameters of 16 µm and 24 µm. The yield strength and modulus of PCL increased with the inclusion of 10% wool, although the elongation was reduced. The crystallinity of the composites was found to be reduced with wool inclusion, though the melting point of PCL remained mostly unchanged with 10% wool inclusion, indicating better compatibility. Good miscibility and uniform structure were observed with the inclusion of 10% wool, as evidenced by rheology and morphology analysis. The impact of fibre fineness was mostly minor, though wool/PCL composites showed improved thermal stability with finer diameter of wool fibres. The printed specimens exhibited an increasing rate of biodegradation in marine water, which was correlated to the amount of wool present. Overall, the results demonstrate the practical applicability of the wool/PCL composition in MEX for the preparation of varied objects, such as containers, toys and other household and industrial items. Using wool/PCL combinations as regular plastics would provide a significant environmental advantage over the non-degradable polymers that are currently used for these purposes.
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Affiliation(s)
| | - Maryam Naebe
- Institute for Frontier Materials, Deakin University, Geelong, VIC 3216, Australia;
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Momeni V, Shahroodi Z, Gonzalez-Gutierrez J, Hentschel L, Duretek I, Schuschnigg S, Kukla C, Holzer C. Effects of Different Polypropylene (PP)-Backbones in Aluminium Feedstock for Fused Filament Fabrication (FFF). Polymers (Basel) 2023; 15:3007. [PMID: 37514397 PMCID: PMC10385633 DOI: 10.3390/polym15143007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 07/06/2023] [Accepted: 07/07/2023] [Indexed: 07/30/2023] Open
Abstract
The current study presents the effect of the backbone as an important binder component on the mechanical, rheological, and thermal properties of Aluminium (Al) alloy feedstocks. A thermoplastic elastomer (TPE) main binder component was blended with either polypropylene (PP), grafted-maleic anhydride-PP (PPMA), or grafted-maleic anhydride-PPwax (PPMAwax) plus PP, as the backbone. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) tests were performed to investigate the thermal properties of binder systems and feedstocks. Fourier-transform infrared (FTIR) spectroscopy was used to study the chemical interaction between the binder and the Al alloy. After making feedstock filaments, tensile tests, scanning electron microscopy (SEM), and fused filament fabrication (FFF) printing were done. The results showed that although the PP printability was acceptable, the best mechanical properties and printed quality can be achieved by PPMA. TGA test showed that all binder systems in the feedstocks could be removed completely around 500 °C. From FTIR, the possibility of chemical reactions between Al alloy particles and maleic anhydride groups on the grafted PP backbone could explain the better dispersion of the mixture and higher mechanical properties. Tensile strength in PP samples was 3.4 MPa which was improved 1.8 times using PPMA as the backbone.
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Affiliation(s)
- Vahid Momeni
- Polymer Processing, Montanuniversitaet Leoben, 8700 Leoben, Austria
| | - Zahra Shahroodi
- Polymer Processing, Montanuniversitaet Leoben, 8700 Leoben, Austria
| | - Joamin Gonzalez-Gutierrez
- Polymer Processing, Montanuniversitaet Leoben, 8700 Leoben, Austria
- Functional Polymers Research Unit, Materials Research and Technology (MRT) Department, Luxembourg Institute of Science and Technology (LIST), L-4940 Hautcharage, Luxembourg
| | - Lukas Hentschel
- Polymer Processing, Montanuniversitaet Leoben, 8700 Leoben, Austria
| | - Ivica Duretek
- Polymer Processing, Montanuniversitaet Leoben, 8700 Leoben, Austria
| | | | - Christian Kukla
- Industrial Liaison Department, Montanuniversitaet Leoben, 8700 Leoben, Austria
| | - Clemens Holzer
- Polymer Processing, Montanuniversitaet Leoben, 8700 Leoben, Austria
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Eickhoff R, Antusch S, Nötzel D, Hanemann T. New Partially Water-Soluble Feedstocks for Additive Manufacturing of Ti6Al4V Parts by Material Extrusion. MATERIALS (BASEL, SWITZERLAND) 2023; 16:3162. [PMID: 37109999 PMCID: PMC10145004 DOI: 10.3390/ma16083162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/02/2023] [Accepted: 04/13/2023] [Indexed: 06/19/2023]
Abstract
In this work, a process chain for the realization of dense Ti6Al4V parts via different material extrusion methods will be introduced applying eco-friendly partially water-soluble binder systems. In continuation of earlier research, polyethylene glycol (PEG) as a low molecular weight binder component was combined either with poly(vinylbutyral) (PVB) or with poly(methylmethacrylat) (PMMA) as a high molecular weight polymer and investigated with respect to their usability in FFF and FFD. The additional investigation of different surfactants' impact on the rheological behaviour applying shear and oscillation rheology allowed for a final solid Ti6Al4V content of 60 vol%, which is sufficient to achieve after printing, debinding and thermal densification parts with densities better than 99% of the theoretical value. The requirements for usage in medical applications according to ASTM F2885-17 can be fulfilled depending on the processing conditions.
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Affiliation(s)
- Ralf Eickhoff
- Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
| | - Steffen Antusch
- Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
| | - Dorit Nötzel
- Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
- Department of Microsystems Engineering, University Freiburg, Georges-Koehler-Allee 102, D-79110 Freiburg, Germany
| | - Thomas Hanemann
- Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
- Department of Microsystems Engineering, University Freiburg, Georges-Koehler-Allee 102, D-79110 Freiburg, Germany
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7
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Sanetrnik D, Hausnerova B, Novak M, Mukund BN. Effect of Particle Size and Shape on Wall Slip of Highly Filled Powder Feedstocks for Material Extrusion and Powder Injection Molding. 3D PRINTING AND ADDITIVE MANUFACTURING 2023; 10:236-244. [PMID: 37095867 PMCID: PMC10122254 DOI: 10.1089/3dp.2021.0157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
A necessity to distinguish between the influence of powder shape and size (particle size distribution) is especially demanding for highly filled metal powder feedstocks employed in additive manufacturing and powder injection molding. As their processability is evaluated through rheological behavior, the study focuses on the effect of powder size/shape on a wall slip, which is a typical phenomenon determining flow performance of these materials. Water and gas atomized 17-4PH stainless steel powders with D 50 of about 3 and 20 μm are admixed into a binder containing low-density polyethylene, ethylene vinyl acetate, and paraffin wax. Mooney analysis to intercept the slip velocity of 55 vol. % filled compounds reveals that wall slip effect appears to vary significantly with size and shape of metal powders-round shaped and large particles are the most prone to the wall slip. However, the evaluation is affected by the type of the flow streams resulting from the geometry of the dies-conical dies reduce the slip up to 60% in case of fine and round particles.
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Affiliation(s)
- Daniel Sanetrnik
- Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Zlin, Czech Republic
| | - Berenika Hausnerova
- Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Zlin, Czech Republic
- Department of Production Engineering, Faculty of Technology, Tomas Bata University in Zlin, Zlin, Czech Republic
- Address correspondence to: Berenika Hausnerova, Department of Production Engineering, Faculty of Technology, Tomas Bata University in Zlin, nam. T.G. Masaryka 5555, Zlin 760 01, Czech Republic
| | - Martin Novak
- Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Zlin, Czech Republic
- Department of Production Engineering, Faculty of Technology, Tomas Bata University in Zlin, Zlin, Czech Republic
| | - Bhimasena Nagaraj Mukund
- Department of Production Engineering, Faculty of Technology, Tomas Bata University in Zlin, Zlin, Czech Republic
- Indo MIM Pvt. Ltd., Bangalore, India
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Balcázar-Zumaeta CR, Castro-Alayo EM, Medina-Mendoza M, Muñoz-Astecker LD, Torrejón-Valqui L, Rodriguez-Perez RJ, Rojas-Ocampo E, Cayo-Colca IS. Physical and Chemical Properties of 70% Cocoa Dark Chocolate Mixed with Freeze-Dried Arazá ( Eugenia stipitata) Pulp. Prev Nutr Food Sci 2022; 27:474-482. [PMID: 36721755 PMCID: PMC9843710 DOI: 10.3746/pnf.2022.27.4.474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 09/01/2022] [Accepted: 10/01/2022] [Indexed: 01/04/2023] Open
Abstract
This work aimed to determine the chemical and physical properties of 70% dark cocoa chocolate, including freeze-dried Arazá (Eugenia stipitata) pulp (FDAP). We studied chocolates incorporating three FDAP concentrations (1.0, 1.5, and 2.0%). No statistical differences were found in total polyphenol content, antioxidant capacity, and total catechin and epicatechin content. The dark chocolates' moisture and texture were unaffected by the FDAP. The Casson yield stress increased to 19.67±1.35 Pa, while the Casson plastic viscosity reduced to 1.68±0.03 Pa·s, Also, the particle size increased. The dark chocolates' flow behavior corresponded to a non-Newtonian fluid. Finally, the dark chocolate's properties were unaffected by a 2% FDAP concentration.
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Affiliation(s)
- César R. Balcázar-Zumaeta
- Instituto de Investigación, Innovación y Desarrollo para el Sector Agrario y Agroindustrial de la Región Amazonas (IIDAA), Facultad de Ingeniería y Ciencias Agrarias, Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas, Chachapoyas, Amazonas 01001, Perú,
Correspondence to César R. Balcázar-Zumaeta, E-mail:
| | - Efraín M. Castro-Alayo
- Instituto de Investigación, Innovación y Desarrollo para el Sector Agrario y Agroindustrial de la Región Amazonas (IIDAA), Facultad de Ingeniería y Ciencias Agrarias, Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas, Chachapoyas, Amazonas 01001, Perú
| | - Marleni Medina-Mendoza
- Instituto de Investigación, Innovación y Desarrollo para el Sector Agrario y Agroindustrial de la Región Amazonas (IIDAA), Facultad de Ingeniería y Ciencias Agrarias, Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas, Chachapoyas, Amazonas 01001, Perú
| | - Lucas D. Muñoz-Astecker
- Instituto de Investigación, Innovación y Desarrollo para el Sector Agrario y Agroindustrial de la Región Amazonas (IIDAA), Facultad de Ingeniería y Ciencias Agrarias, Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas, Chachapoyas, Amazonas 01001, Perú
| | - Llisela Torrejón-Valqui
- Instituto de Investigación, Innovación y Desarrollo para el Sector Agrario y Agroindustrial de la Región Amazonas (IIDAA), Facultad de Ingeniería y Ciencias Agrarias, Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas, Chachapoyas, Amazonas 01001, Perú
| | - Roxana J. Rodriguez-Perez
- Instituto de Investigación, Innovación y Desarrollo para el Sector Agrario y Agroindustrial de la Región Amazonas (IIDAA), Facultad de Ingeniería y Ciencias Agrarias, Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas, Chachapoyas, Amazonas 01001, Perú
| | - Elizabeth Rojas-Ocampo
- Instituto de Investigación, Innovación y Desarrollo para el Sector Agrario y Agroindustrial de la Región Amazonas (IIDAA), Facultad de Ingeniería y Ciencias Agrarias, Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas, Chachapoyas, Amazonas 01001, Perú
| | - Ilse S. Cayo-Colca
- Facultad de Ingeniería Zootecnista, Agronegocios y Biotecnología, Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas, Chachapoyas, Amazonas 01001, Perú
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9
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Momeni V, Hufnagl M, Shahroodi Z, Gonzalez-Gutierrez J, Schuschnigg S, Kukla C, Holzer C. Research Progress on Low-Pressure Powder Injection Molding. MATERIALS (BASEL, SWITZERLAND) 2022; 16:379. [PMID: 36614718 PMCID: PMC9822315 DOI: 10.3390/ma16010379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 12/25/2022] [Accepted: 12/28/2022] [Indexed: 06/17/2023]
Abstract
Powder injection molding (PIM) is a well-known technique to manufacture net-shaped, complicated, macro or micro parts employing a wide range of materials and alloys. Depending on the pressure applied to inject the feedstock, this process can be separated into low-pressure (LPIM) and high-pressure (HPIM) injection molding. Although the LPIM and HPIM processes are theoretically similar, all steps have substantial differences, particularly feedstock preparation, injection, and debinding. After decades of focusing on HPIM, low-viscosity feedstocks with improved flowability have recently been produced utilizing low-molecular-weight polymers for LPIM. It has been proven that LPIM can be used for making parts in low quantities or mass production. Compared to HPIM, which could only be used for the mass production of metallic and ceramic components, LPIM can give an outstanding opportunity to cover applications in low or large batch production rates. Due to the use of low-cost equipment, LPIM also provides several economic benefits. However, establishing an optimal binder system for all powders that should be injected at extremely low pressures (below 1 MPa) is challenging. Therefore, various defects may occur throughout the mixing, injection, debinding, and sintering stages. Since all steps in the process are interrelated, it is important to have a general picture of the whole process which needs a scientific overview. This paper reviews the potential of LPIM and the characteristics of all steps. A complete academic and research background survey on the applications, challenges, and prospects has been indicated. It can be concluded that although many challenges of LPIM have been solved, it could be a proper solution to use this process and materials in developing new applications for technologies such as additive manufacturing and processing of sensitive alloys.
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Affiliation(s)
- Vahid Momeni
- Polymer Processing, Montanuniversitaet Leoben, 8700 Leoben, Austria
| | | | - Zahra Shahroodi
- Polymer Processing, Montanuniversitaet Leoben, 8700 Leoben, Austria
| | - Joamin Gonzalez-Gutierrez
- Polymer Processing, Montanuniversitaet Leoben, 8700 Leoben, Austria
- Functional Polymers Research Unit, Materials Research and Technology (MRT) Department, Luxembourg Institute of Science and Technology (LIST), L-4940 Luxembourg, Luxembourg
| | | | - Christian Kukla
- Industrial Liaison Department, Montanuniversitaet Leoben, 8700 Leoben, Austria
| | - Clemens Holzer
- Polymer Processing, Montanuniversitaet Leoben, 8700 Leoben, Austria
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10
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Ahangarkolaei HF, Mashkour M, Rasouli D. Superparamagnetic wood‐polypropylene nanocomposite made using magnetic wood flour with a nanoparticle‐free surface. J Appl Polym Sci 2022. [DOI: 10.1002/app.53531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Hassan Fallah Ahangarkolaei
- Laboratory of Sustainable Nanomaterials, Department of Wood Engineering and Technology Gorgan University of Agricultural Sciences and Natural Resources Gorgan Iran
| | - Mahdi Mashkour
- Laboratory of Sustainable Nanomaterials, Department of Wood Engineering and Technology Gorgan University of Agricultural Sciences and Natural Resources Gorgan Iran
| | - Davood Rasouli
- Laboratory of Sustainable Nanomaterials, Department of Wood Engineering and Technology Gorgan University of Agricultural Sciences and Natural Resources Gorgan Iran
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11
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Hejazi ES, Masoomi M. Investigation the effect of processing condition and dispersed phase content on rheology–morphology relationship in polypropylene/polyethylene terephthalate microfibrillar composite. POLYM ADVAN TECHNOL 2022. [DOI: 10.1002/pat.5936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Elahe sadat Hejazi
- Department of Chemical Engineering (Polymer Group) Isfahan University of Technology Isfahan Iran
| | - Mahmood Masoomi
- Department of Chemical Engineering (Polymer Group) Isfahan University of Technology Isfahan Iran
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12
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Piezoelectric MoS2 Nanoflowers (NF's) for Targeted Cancer Therapy by Gelatin-based Shear Thinning Hydrogels. In vitro and In vivo trials. REACT FUNCT POLYM 2022. [DOI: 10.1016/j.reactfunctpolym.2022.105435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Eickhoff R, Antusch S, Baumgärtner S, Nötzel D, Hanemann T. Feedstock Development for Material Extrusion-Based Printing of Ti6Al4V Parts. MATERIALS (BASEL, SWITZERLAND) 2022; 15:ma15186442. [PMID: 36143753 PMCID: PMC9502915 DOI: 10.3390/ma15186442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 09/08/2022] [Accepted: 09/13/2022] [Indexed: 05/14/2023]
Abstract
In this work, a holistic approach for the fabrication of dense Ti6Al4V parts via material extrusion methods (MEX), such as fused filament fabrication (FFF) or fused feedstock deposition (FFD), will be presented. With respect to the requirements of the printing process, a comprehensive investigation of the feedstock development will be described. This covers mainly the amount ratio variation of the main binder components LDPE (low-density polyethylene), HDPE (high-density polyethylene), and wax, characterized by shear and oscillation rheology. Solid content of 60 vol% allowed the 3D printing of even more complex small parts in a reproducible manner. In some cases, the pellet-based FFD seems to be superior to the established FFF. After sintering, a density of 96.6% of theory could be achieved, an additional hot isostatic pressing delivered density values better than 99% of theory. The requirements (mechanical properties, carbon, and oxygen content) for the usage of medical implants (following ASTM F2885-17) were partially fulfilled or shortly missed.
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Affiliation(s)
- Ralf Eickhoff
- Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
| | - Steffen Antusch
- Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
| | - Siegfried Baumgärtner
- Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
| | - Dorit Nötzel
- Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
- Department of Microsystems Engineering, University Freiburg, Georges-Koehler-Allee 102,D-79110 Freiburg, Germany
| | - Thomas Hanemann
- Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
- Department of Microsystems Engineering, University Freiburg, Georges-Koehler-Allee 102,D-79110 Freiburg, Germany
- Correspondence: or ; Tel.: +49-721-608-22585
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14
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Effect of Increased Powder-Binder Adhesion by Backbone Grafting on the Properties of Feedstocks for Ceramic Injection Molding. Polymers (Basel) 2022; 14:polym14173653. [PMID: 36080728 PMCID: PMC9460726 DOI: 10.3390/polym14173653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 08/27/2022] [Accepted: 08/28/2022] [Indexed: 11/22/2022] Open
Abstract
The good interaction between the ceramic powder and the binder system is vital for ceramic injection molding and prevents the phase separation during processing. Due to the non-polar structure of polyolefins such as high-density polyethylene (HDPE) and the polar surface of ceramics such as zirconia, there is not appropriate adhesion between them. In this study, the effect of adding high-density polyethylene grafted with acrylic acid (AAHDPE), with high polarity and strong adhesion to the powder, on the rheological, thermal and chemical properties of polymer composites highly filled with zirconia and feedstocks was evaluated. To gain a deeper understanding of the effect of each component, formulations containing different amounts of HDPE and or AAHDPE, zirconia and paraffin wax (PW) were prepared. Attenuated total reflection spectroscopy (ATR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and rotational and capillary rheology were used for the characterization of the different formulations. The ATR analysis revealed the formation of hydrogen bonds between the hydroxyl groups on the zirconia surface and AAHDPE. The improved powder-binder adhesion in the formulations with more AAHDPE resulted in a better powder dispersion and homogeneous mixtures, as observed by SEM. DSC results revealed that the addition of AAHDPE, PW and zirconia effect the melting and crystallization temperature and crystallinity of the binder, the polymer-filled system and feedstocks. The better powder--binder adhesion and powder dispersion effectively decreased the viscosity of the highly filled polymer composites and feedstocks with AAHDPE; this showed the potential of grafted polymers as binders for ceramic injection molding.
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Ismail NH, Awang RA, Kannan TP, Abdul Hamid ZA, Jaafar M. Physicomechanical and cytotoxic effects of a newly developed dental hybrid composite adhesive cement reinforced with zirconia and alumina. Polym Bull (Berl) 2022. [DOI: 10.1007/s00289-022-04381-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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17
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Ceraulo M, La Mantia FP, Mistretta MC, Titone V. The Use of Waste Hazelnut Shells as a Reinforcement in the Development of Green Biocomposites. Polymers (Basel) 2022; 14:polym14112151. [PMID: 35683824 PMCID: PMC9182734 DOI: 10.3390/polym14112151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 05/11/2022] [Accepted: 05/23/2022] [Indexed: 11/16/2022] Open
Abstract
Biodegradable Mater-Bi (MB) composites reinforced with hazelnut shell (HS) powder were prepared in a co-rotating twin-screw extruder followed by compression molding and injection molding. The effects of reinforcement on the morphology, static and dynamic mechanical properties, and thermal and rheological properties of MB/HS biocomposites were studied. Rheological tests showed that the incorporation of HS significantly increased the viscosity of composites with non-Newtonian behavior at low frequencies. On the other hand, a scanning electron microscope (SEM) examination revealed poor interfacial adhesion between the matrix and the filler. The thermal property results indicated that HS could act as a nucleating agent to promote the crystallization properties of biocomposites. Furthermore, the experimental results indicated that the addition of HS led to a significant improvement in the thermomechanical stability of the composites. This paper demonstrates that the incorporation of a low-cost waste product, such as hazelnut shells, is a practical way to produce low-cost biocomposites with good properties. With a content of HS of 10%, a remarkable improvement in the elastic modulus and impact strength was observed in both compression and injection-molded samples. With a higher content of HS, however, the processability in injection molding was strongly worsened.
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Affiliation(s)
- Manuela Ceraulo
- Department of Engineering, University of Palermo, VialedelleScienze, 90128 Palermo, Italy; (F.P.L.M.); (M.C.M.); (V.T.)
- INSTM, Consortium for Materials Science and Technology, Via Giusti 9, 50125 Florence, Italy
- Correspondence:
| | - Francesco Paolo La Mantia
- Department of Engineering, University of Palermo, VialedelleScienze, 90128 Palermo, Italy; (F.P.L.M.); (M.C.M.); (V.T.)
- INSTM, Consortium for Materials Science and Technology, Via Giusti 9, 50125 Florence, Italy
| | - Maria Chiara Mistretta
- Department of Engineering, University of Palermo, VialedelleScienze, 90128 Palermo, Italy; (F.P.L.M.); (M.C.M.); (V.T.)
| | - Vincenzo Titone
- Department of Engineering, University of Palermo, VialedelleScienze, 90128 Palermo, Italy; (F.P.L.M.); (M.C.M.); (V.T.)
- Irritec S.p.A., Via Industriale sn, 98070 Rocca di Caprileone, Italy
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18
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Saberi A, Behnamghader A, Aghabarari B, Yousefi A, Majda D, Huerta MVM, Mozafari M. 3D direct printing of composite bone scaffolds containing polylactic acid and spray dried mesoporous bioactive glass-ceramic microparticles. Int J Biol Macromol 2022; 207:9-22. [PMID: 35181332 DOI: 10.1016/j.ijbiomac.2022.02.067] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Revised: 02/06/2022] [Accepted: 02/12/2022] [Indexed: 01/20/2023]
Abstract
In this study, a three-dimensional composite scaffold is proposed consisting of polylactic acid and spray dried glass-ceramic microparticles (SGCMs). The compositional and structural characterization showed that the obtained spray dried powder formed as glass-ceramic (GC) with a completely interconnected porosity structure. Before direct printing of scaffolds, the rheological behavior of polylactic acid (PLA) and PLA-GC (PLA matrix containing SGCMs) inks were investigated. The PLA-GC composite ink represents sharper shear-thinning behavior and higher loss and storage modulus comparable to that of pure PLA. Microscopic observations and elemental mapping elements showed that 3D scaffolds had well-defined interconnected porosity and uniform distribution of the glass-ceramic particles. Mechanical tests indicated that compression strength is dependent on the scaffold porosity and the presence of SGCMs. Apatite formation evaluation besides ion release study showed better biomineralization capacity of PLA-GC scaffolds, as larger and denser sediments formed on the PLA-GC scaffolds after 7- and 14-day soaking. The preliminary cell response was studied with primary human mesenchymal stem cells (hMSCs) and revealed that SGCMs improved cell adhesion and viability and ALP activity. The appropriate combination of the biomaterials/methods to fabricate 3D porous constructs and their available bioactivity and biocompatibility, both being important characteristics for bone tissue engineering applications.
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Affiliation(s)
- Azadeh Saberi
- Department of Nanotechnology and Advanced Materials, Materials and Energy Research Center, Tehran, Iran
| | - Aliasghar Behnamghader
- Department of Nanotechnology and Advanced Materials, Materials and Energy Research Center, Tehran, Iran.
| | - Behzad Aghabarari
- Department of Nanotechnology and Advanced Materials, Materials and Energy Research Center, Tehran, Iran
| | - Aliakbar Yousefi
- Department of Polymer Processing, Iran Polymer and Petrochemical Institute, Tehran, Iran
| | - Dorota Majda
- Department of Chemical technology, Jagiellonian University, Kraków, Poland
| | | | - Masoud Mozafari
- Department of Tissue Engineering & Regenerative Medicine, Iran University of Medical Sciences, Tehran, Iran.
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Yussuf AA, Al‐Saleh MA, Al‐Enezi ST, Samuel J, Al‐Banna A, Kadhmi R, Abraham G. The influence of flame retardant filler on the mechanical, thermal, rheological and flame retardancy properties of silane crosslinked linear low density polyethylene/low density polyethylene blend nanocomposite. J Appl Polym Sci 2022. [DOI: 10.1002/app.52447] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Abdirahman A. Yussuf
- Polymeric Products and Customization Program Petroleum Research Center, Kuwait Institute for Scientific Research Safat Kuwait
| | - Mohammad A. Al‐Saleh
- Polymeric Products and Customization Program Petroleum Research Center, Kuwait Institute for Scientific Research Safat Kuwait
| | - Salah T. Al‐Enezi
- Polymeric Products and Customization Program Petroleum Research Center, Kuwait Institute for Scientific Research Safat Kuwait
| | - Jacob Samuel
- Polymeric Products and Customization Program Petroleum Research Center, Kuwait Institute for Scientific Research Safat Kuwait
| | - Aseel Al‐Banna
- Polymeric Products and Customization Program Petroleum Research Center, Kuwait Institute for Scientific Research Safat Kuwait
| | - Roaya Kadhmi
- Polymeric Products and Customization Program Petroleum Research Center, Kuwait Institute for Scientific Research Safat Kuwait
| | - Gils Abraham
- Polymeric Products and Customization Program Petroleum Research Center, Kuwait Institute for Scientific Research Safat Kuwait
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20
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Tran K, Chalamet Y, Mignard N, Carrot C, Gyppaz F, Auvray T. Kinetics of geopolymerization followed by rheology: a general model. SOFT MATTER 2022; 18:2549-2557. [PMID: 35293404 DOI: 10.1039/d1sm01718g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The geopolymerization process necessitates the activation of an aluminosilicate source by an alkaline solution. Its kinetics is followed by rheology. The storage modulus (G') and loss modulus (G'') are monitored through oscillatory rheological measurements from the early stage, geopolymer paste, to the gel point with the formation of a geopolymer network. The results show that the temperature increase shortens the reaction time. The principle of Reaction Time-Temperature Superposition (RTTS) is introduced to predict this phenomenon. Furthermore, it is pointed out that using metakaolin blends with different reactivities allows modifying and controlling the reaction time. A critical weight fraction of reactive metakaolin is identified as necessary for the formation of the geopolymer network. The reaction times of the different formulations are linked to the temperature and the weight fraction of metakaolin by the Arrhenius law. A model is established to predict the reaction time according to the temperature and the weight fraction between the two metakaolins used.
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Affiliation(s)
- Kelly Tran
- Univ Lyon, UJM-Saint-Etienne, CNRS, IMP, UMR 5223, Saint-Etienne, France.
| | - Yvan Chalamet
- Univ Lyon, UJM-Saint-Etienne, CNRS, IMP, UMR 5223, Saint-Etienne, France.
| | - Nathalie Mignard
- Univ Lyon, UJM-Saint-Etienne, CNRS, IMP, UMR 5223, Saint-Etienne, France.
| | - Christian Carrot
- Univ Lyon, UJM-Saint-Etienne, CNRS, IMP, UMR 5223, Saint-Etienne, France.
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21
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Kontaxis LC, Kozaniti FK, Papanicolaou GC. Mechanical Behavior Modelling and Filler Geometry Effect of Glass Filler Reinforced Starch-Epoxy Hybrid Matrix Composites. MATERIALS 2021; 14:ma14216587. [PMID: 34772113 PMCID: PMC8585403 DOI: 10.3390/ma14216587] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/22/2021] [Accepted: 10/28/2021] [Indexed: 11/24/2022]
Abstract
The aim of the present study is to investigate the inclusion geometry and concentration effect on the quasi-static properties of a starch-epoxy hybrid matrix composite. The composites investigated consisted of a starch-epoxy hybrid matrix reinforced with four different glass inclusions such as 3 mm long chopped strands, 0.2 mm long short glass fibers, glass beads (120 μm in diameter) and glass bubbles (65 μm in diameter) at different concentrations. The flexural modulus and the strength of all materials tested were determined using three-point bending tests. The Property Prediction Model (PPM) was applied to predict the experimental findings. The model predicted remarkably well the mechanical behavior of all the materials manufactured and tested. The maximum value of the flexural modulus in the case of the 3 mm long chopped strands was found to be 75% greater than the modulus of the hybrid matrix. Furthermore, adding glass beads in the hybrid matrix led to a simultaneous increase in both the flexural modulus and the strength.
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22
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Nötzel D, Eickhoff R, Pfeifer C, Hanemann T. Printing of Zirconia Parts via Fused Filament Fabrication. MATERIALS 2021; 14:ma14195467. [PMID: 34639866 PMCID: PMC8509539 DOI: 10.3390/ma14195467] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/15/2021] [Accepted: 09/17/2021] [Indexed: 12/27/2022]
Abstract
In this work, a process chain for the fabrication of dense zirconia parts will be presented covering the individual steps feedstock compounding, 3D printing via Fused Filament Fabrication (FFF) and thermal postprocessing including debinding and sintering. A special focus was set on the comprehensive rheological characterization of the feedstock systems applying high-pressure capillary and oscillation rheometry. The latter allowed the representation of the flow situation especially in the nozzle of the print head with the occurring low-shear stress. Oscillation rheometry enabled the clarification of the surfactant’s concentration, here stearic acid, or more general, the feedstocks composition influence on the resulting feedstock flow behavior. Finally, dense ceramic parts (best values around 99 % of theory) were realized with structural details smaller than 100 µm.
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Affiliation(s)
- Dorit Nötzel
- Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany; (D.N.); (R.E.)
- Department of Microsystems Engineering, University Freiburg, Georges-Koehler-Allee 102, D-79110 Freiburg, Germany;
| | - Ralf Eickhoff
- Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany; (D.N.); (R.E.)
| | - Christoph Pfeifer
- Department of Microsystems Engineering, University Freiburg, Georges-Koehler-Allee 102, D-79110 Freiburg, Germany;
| | - Thomas Hanemann
- Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany; (D.N.); (R.E.)
- Department of Microsystems Engineering, University Freiburg, Georges-Koehler-Allee 102, D-79110 Freiburg, Germany;
- Correspondence: or ; Tel.: +49-721-608-22585
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Abstract
Various types of additives have been diachronically used in historic mortars, whereas their use in lime-based grouts, used for the restoration of historic structures, is rather limited. In this study, an effort was made to investigate the performance of glass additives in grouts, consisting of lime and natural pozzolan. The additives concerned glass fibers (3 and 6 mm in length), glass beads and bubbles, added in a proportion 0.3–3% w/w of binders. Five grout compositions were manufactured and their properties at fresh and hardened states were tested. From the evaluation of the results, it was asserted that glass additives influenced the grouts’ performance in a favorable way. Their fresh state and physical properties were maintained or slightly improved, while there was a significant enhancement of the long-term mechanical characteristics of the mixes. Additionally, the adhesion capability of grouts was notably increased, which is a crucial aspect indicating their efficacy.
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