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Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties

A special issue of Materials (ISSN 1996-1944).

Deadline for manuscript submissions: closed (31 January 2019) | Viewed by 75510

Printed Edition Available!
A printed edition of this Special Issue is available here.

Special Issue Editors

Prof. Dr. Giuseppe Titomanlio

E-Mail Website
Guest Editor
Department of Industrial Engineering, University of Salerno, Fisciano (SA), Italy
Interests: polymer processing; flow-induced crystallization and effect of crystallinity on rheology; morphology evolution during polymer processing; injection molding simulation
Special Issues, Collections and Topics in MDPI journals
Dr. Vito Speranza

E-Mail Website
Guest Editor
Department of Industrial Engineering, University of Salerno, Fisciano (SA), Italy
Interests: molding; effect of thermomechanical history on final structure of polymeric materials; analysis and numerical simulation of the injection molding process of thermoplastic materials; polymeric materials characterization; atomic force microscopy
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The analysis of polymer processing operations is a very wide and complex subject; indeed, during polymer processing, viscoelastic fluids are forced to deform into desired geometries using non-homogeneous velocity and temperature fields down to solidification. The objective of analysis is certainly the identification of processing conditions, which, more and more, are finalized to the optimization of product final properties, which, in their turn, are determined by the final part morphology.

Depending on the operating conditions, the properties of the final part can change even more than one order of magnitude. Properties of interest are certainly the mechanical, optical, barrier properties, the permeability, biodegradability and any other property of practical relevance including the characteristics of the surfaces as its finishing and wettability, which are connected one to the other.

The aim of this Special Issue is to select progresses or reviews in the understanding/description of the phenomena involved along the chain: Processing–morphology–properties. Obviously, along this virtual chain, the modeling may be a very useful approach  and within the objective of understanding  fundamental aspects it may also be relevant to compare selected characteristics of the process and of the material with characteristics of the resulting morphology and then with the properties of the final part. This approach suggested the title: “Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties”.

Prof. Dr. Giuseppe Titomanlio
Dr. Vito Speranza
Guest Editors

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Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • polymer processing
  • modeling morphology evolution
  • morphology of polymeric parts in relation to their processing
  • morphology-properties relationships of polymeric parts
  • polymeric part properties

Published Papers (13 papers)

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Editorial

Jump to: Research, Review

3 pages, 151 KiB  
Editorial
Polymer Processing: Modeling and Correlations Finalized to Tailoring Plastic Part Morphology and Properties
by Giuseppe Titomanlio and Vito Speranza
Materials 2019, 12(8), 1217; https://doi.org/10.3390/ma12081217 - 14 Apr 2019
Viewed by 2103
Abstract
The analysis of polymer processing operations requires the description of simultaneous transient momentum and heat transfer down to material solidification. The aim of the analysis is to improve and, hopefully, optimize the final properties that are determined by the final morphology of the [...] Read more.
The analysis of polymer processing operations requires the description of simultaneous transient momentum and heat transfer down to material solidification. The aim of the analysis is to improve and, hopefully, optimize the final properties that are determined by the final morphology of the part. In this special issue, consisting of 1 review and 11 research articles detailing several polymer processing operations, experimental and numerical analyses have been conducted in order to identify and describe the main relevant phenomena, that affect the product morphologies and properties. Full article
(This article belongs to the Special Issue Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties)

Research

Jump to: Editorial, Review

8 pages, 2167 KiB  
Article
Laser-Assisted Thermal Imprinting of Microlens Arrays—Effects of Pressing Pressure and Pattern Size
by Keisuke Nagato, Yuki Yajima and Masayuki Nakao
Materials 2019, 12(4), 675; https://doi.org/10.3390/ma12040675 - 25 Feb 2019
Cited by 11 | Viewed by 3562
Abstract
Polymer films with nano- or microstructured surfaces have been widely applied to optical devices, bioplates, and printed electronics. Laser-assisted thermal imprinting (LATI), in which a laser directly heats the surfaces of a mold and a thermoplastic polymer, is one of the high-throughput methods [...] Read more.
Polymer films with nano- or microstructured surfaces have been widely applied to optical devices, bioplates, and printed electronics. Laser-assisted thermal imprinting (LATI), in which a laser directly heats the surfaces of a mold and a thermoplastic polymer, is one of the high-throughput methods of replicating nano- or microstructures on polymer films. Only the surfaces of the mold and polymer film are heated and cooled rapidly, therefore it is possible to replicate nano- or microstructures on polymer films more rapidly than by using conventional thermal nanoimprinting. In this study, microlens arrays (MLAs) were replicated on polymethylmethacrylate (PMMA) films using LATI, and the effects of the pressing pressure (10−50 MPa) and the pattern size (33- and 5-μm pitch) of the MLA on the filling ratio were investigated by analyzing a microlens replicated using different laser-irradiation times (0.1−2 ms). The filling ratio increased with increasing pressing pressure and laser-irradiation time in the replication of MLAs with varying sizes, while the flow of the PMMA varied with the pressing pressure and laser-irradiation time. It was found that during filling, the shape of the polymer cross-sectional surface demonstrated a double and single peak in the 33- and 5-μm-pitch patterns, respectively. This was because the depth of the heated area in the 33-μm-pitch pattern was smaller than the pattern size, whereas that of the 5-μm-pitch pattern was comparable to (or larger) than the pattern size. Full article
(This article belongs to the Special Issue Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties)
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16 pages, 8541 KiB  
Article
3D Numerical Simulation of Reactive Extrusion Processes for Preparing PP/TiO2 Nanocomposites in a Corotating Twin Screw Extruder
by Dapeng Sun, Xiangzhe Zhu and Mingguang Gao
Materials 2019, 12(4), 671; https://doi.org/10.3390/ma12040671 - 23 Feb 2019
Cited by 12 | Viewed by 5592
Abstract
To better understand the relationship between flow, mixing and reactions in the process of preparing PP/TiO2, a 3D numerical simulation in a co-rotating twin screw extruder (TSE) was firstly employed using commercial CFD code, ANSYS Polyflow. The effects of rotating speed [...] Read more.
To better understand the relationship between flow, mixing and reactions in the process of preparing PP/TiO2, a 3D numerical simulation in a co-rotating twin screw extruder (TSE) was firstly employed using commercial CFD code, ANSYS Polyflow. The effects of rotating speed of screws, stagger angle of knead blocks, inlet flow rate and initial temperature of barrel on the mixing and reaction process in the TSE were investigated. The results reveal that the studied operational and geometric parameters, which determine mixing efficiency, residence time distribution, and temperature of the flows in the TSE, affect the local species concentration, reaction time and reaction rate, and hence have great influences on the conversion rate. The results show that increasing the rotating speed and inlet flow rate can decrease the time for sufficient mixing, which is not conducive to intensive reaction, and increasing the stagger angle has the opposite effect. Moreover, the conversion rate greatly affected by the initial temperature of barrel. Full article
(This article belongs to the Special Issue Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties)
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Graphical abstract

15 pages, 3095 KiB  
Article
Process Induced Morphology Development of Isotactic Polypropylene on the Basis of Molecular Stretch and Mechanical Work Evolutions
by Sara Liparoti, Vito Speranza, Roberto Pantani and Giuseppe Titomanlio
Materials 2019, 12(3), 505; https://doi.org/10.3390/ma12030505 - 07 Feb 2019
Cited by 13 | Viewed by 2332
Abstract
It is well known that under high shear rates polymers tend to solidify with formation of morphological elements oriented and aligned along the flow direction. On the other hand, stretched polymer chains may not have sufficient time to undergo the structuring steps, which [...] Read more.
It is well known that under high shear rates polymers tend to solidify with formation of morphological elements oriented and aligned along the flow direction. On the other hand, stretched polymer chains may not have sufficient time to undergo the structuring steps, which give rise to fibrillar morphology. In the last decades, several authors have proposed a combined criterion based on both a critical shear rate and a critical mechanical work, which guaranties adequate time for molecular structuring. In this paper, the criterion, reformulated on the basis of critical values of both molecular stretch and mechanical work and adjusted to account for the unsteady character of the polymer processing operations, is applied to the analysis of a set of isotactic polypropylene injection molded samples obtained under very different thermal boundary conditions. The evolutions of molecular stretch and mechanical work are evaluated using process simulation. The results of the model reproduce the main characteristics of the morphology distribution detected on the cross sections of moldings, obtained under very different thermal boundary conditions, assuming that the critical work is a function of temperature. Full article
(This article belongs to the Special Issue Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties)
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16 pages, 5282 KiB  
Article
Hierarchical Structure of iPP During Injection Molding Process with Fast Mold Temperature Evolution
by Vito Speranza, Sara Liparoti, Roberto Pantani and Giuseppe Titomanlio
Materials 2019, 12(3), 424; https://doi.org/10.3390/ma12030424 - 30 Jan 2019
Cited by 30 | Viewed by 3152 | Correction
Abstract
Mold surface temperature strongly influences the molecular orientation and morphology developed in injection molded samples. In this work, an isotactic polypropylene was injected into a rectangular mold, in which the cavity surface temperature was properly modulated during the process by an electrical heating [...] Read more.
Mold surface temperature strongly influences the molecular orientation and morphology developed in injection molded samples. In this work, an isotactic polypropylene was injected into a rectangular mold, in which the cavity surface temperature was properly modulated during the process by an electrical heating device. The induced thermo-mechanical histories strongly influenced the morphology developed in the injection molded parts. Polarized optical microscope and atomic force microscope were adopted for morphological investigations. The combination of flow field and cooling rate experienced by the polymer determined the hierarchical structure. Under strong flow fields and high temperatures, a tightly packed structure, called shish-kebab, aligned along the flow direction, was observed. Under weak flow fields, the formation of β-phase, as cylindrites form, was observed. The formation of each morphological structure was analyzed and discussed on the bases of the flow and temperature fields, experienced by the polymer during each stage of the injection molding process. Full article
(This article belongs to the Special Issue Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties)
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16 pages, 9867 KiB  
Article
Multi-Objective Optimizations for Microinjection Molding Process Parameters of Biodegradable Polymer Stent
by Hongxia Li, Kui Liu, Danyang Zhao, Minjie Wang, Qian Li and Jianhua Hou
Materials 2018, 11(11), 2322; https://doi.org/10.3390/ma11112322 - 19 Nov 2018
Cited by 17 | Viewed by 3284
Abstract
Microinjection molding technology for degradable polymer stents has good development potential. However, there is a very complicated relationship between molding quality and process parameters of microinjection, and it is hard to determine the best combination of process parameters to optimize the molding quality [...] Read more.
Microinjection molding technology for degradable polymer stents has good development potential. However, there is a very complicated relationship between molding quality and process parameters of microinjection, and it is hard to determine the best combination of process parameters to optimize the molding quality of polymer stent. In this study, an adaptive optimization method based on the kriging surrogate model is proposed to reduce the residual stress and warpage of stent during its injection molding. Integrating design of experiment (DOE) methods with the kriging surrogate model can approximate the functional relationship between design goals and design variables, replacing the expensive reanalysis of the stent residual stress and warpage during the optimization process. In this proposed optimization algorithm, expected improvement (EI) is used to balance local and global search. The finite element method (FEM) is used to simulate the micro-injection molding process of polymer stent. As an example, a typical polymer vascular stent ART18Z was studied, where four key process parameters are selected to be the design variables. Numerical results demonstrate that the proposed adaptive optimization method can effectively decrease the residual stress and warpage during the stent injection molding process. Full article
(This article belongs to the Special Issue Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties)
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14 pages, 6821 KiB  
Article
Structural Formation of UHMWPE Film Tracked by Real-Time Retardation Measurements during Uniaxial/Biaxial Stretching
by Yoshinori Hashimoto, Shotaro Nishitsuji, Takashi Kurose and Hiroshi Ito
Materials 2018, 11(11), 2292; https://doi.org/10.3390/ma11112292 - 15 Nov 2018
Cited by 5 | Viewed by 4128
Abstract
This work reports on an experimental study of the stretching of ultra-high molecular weight polyethylene (UHMWPE) film in various uniaxial/biaxial stretching modes at various temperatures and stretching speeds. We examined the stress-birefringence relationship as a stress-optical rule (SOR) under uniaxial stretching and evaluated [...] Read more.
This work reports on an experimental study of the stretching of ultra-high molecular weight polyethylene (UHMWPE) film in various uniaxial/biaxial stretching modes at various temperatures and stretching speeds. We examined the stress-birefringence relationship as a stress-optical rule (SOR) under uniaxial stretching and evaluated the stress-optical coefficient (SOC). Wide-angle X-ray diffraction (WAXD) measurements were applied to evaluate the contribution to birefringence of the crystalline and amorphous phases and to characterize stretching modes. In simultaneous biaxial stretching, the melting temperature (Tm) proved critical to structural formation. We applied thermal analysis techniques and tensile testing to evaluate higher order structures after each stretching mode. Full article
(This article belongs to the Special Issue Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties)
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17 pages, 9314 KiB  
Article
Chaotic Manifold Analysis of Four-Screw Extruders Based on Lagrangian Coherent Structures
by Xiang Zhe Zhu, Ying Tong and Yue Xin Hu
Materials 2018, 11(11), 2272; https://doi.org/10.3390/ma11112272 - 14 Nov 2018
Cited by 7 | Viewed by 2679
Abstract
The four-screw extruder (FSE) is a novel equipment for polymer processing. In this paper, from a new viewpoint of Lagrangian coherent structures (LCS), two-dimensional fluid transport and chaotic mixing characteristics within three kinds of novel industrial FSEs are explored based on LCS to [...] Read more.
The four-screw extruder (FSE) is a novel equipment for polymer processing. In this paper, from a new viewpoint of Lagrangian coherent structures (LCS), two-dimensional fluid transport and chaotic mixing characteristics within three kinds of novel industrial FSEs are explored based on LCS to better understand the flow and mixing natures in the FSEs. Firstly, based on the finite-time invariant manifold theory, the finite-time Lyapunov exponent (FTLE) and LCS of FSEs are calculated by considering the different initial time. Hyperbolic LCSs from the FTLE maps are adopted to identify chaotic mixing manifolds in FSEs. Moreover, particle tracking and Poincaré sections are used to illustrate the different fluid motions in the above three isolated regions. Finally, the effects of relative rotating directions and layout of four screws on the chaotic manifolds in FESs are discussed in order to enhance local mixing performance. Furthermore, quantitative mixing measures, such as the segregation scale, logarithmic of stretching, and mean-time mixing efficiency are employed to compare the mixing efficiencies in three kinds of FSEs. The results show that the relative rotating directions and positions of four screws can change the chaotic manifolds and increase mixing performance in local poor mixing regions. FTLE and LCS analysis are helpful to better understand the chaotic mixing nature in the novel screw extruders. Full article
(This article belongs to the Special Issue Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties)
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21 pages, 6017 KiB  
Article
Silk as a Natural Reinforcement: Processing and Properties of Silk/Epoxy Composite Laminates
by Youssef K. Hamidi, M. Akif Yalcinkaya, Gorkem E. Guloglu, Maya Pishvar, Mehrad Amirkhosravi and M. Cengiz Altan
Materials 2018, 11(11), 2135; https://doi.org/10.3390/ma11112135 - 30 Oct 2018
Cited by 27 | Viewed by 5919
Abstract
With growing environmental awareness, natural fibers have recently received significant interest as reinforcement in polymer composites. Among natural fibers, silk can potentially be a natural alternative to glass fibers, as it possesses comparable specific mechanical properties. In order to investigate the processability and [...] Read more.
With growing environmental awareness, natural fibers have recently received significant interest as reinforcement in polymer composites. Among natural fibers, silk can potentially be a natural alternative to glass fibers, as it possesses comparable specific mechanical properties. In order to investigate the processability and properties of silk reinforced composites, vacuum assisted resin transfer molding (VARTM) was used to manufacture composite laminates reinforced with woven silk preforms. Specific mechanical properties of silk/epoxy laminates were found to be anisotropic and comparable to those of glass/epoxy. Silk composites even exhibited a 23% improvement of specific flexural strength along the principal weave direction over the glass/epoxy laminate. Applying 300 kPa external pressure after resin infusion was found to improve the silk/epoxy interface, leading to a discernible increase in breaking energy and interlaminar shear strength. Moreover, the effect of fabric moisture on the laminate properties was investigated. Unlike glass mats, silk fabric was found to be prone to moisture absorption from the environment. Moisture presence in silk fabric prior to laminate fabrication yielded slower fill times and reduced mechanical properties. On average, 10% fabric moisture induced a 25% and 20% reduction in specific flexural strength and modulus, respectively. Full article
(This article belongs to the Special Issue Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties)
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19 pages, 5233 KiB  
Article
Replication of Micro- and Nanofeatures in Injection Molding of Two PLA Grades with Rapid Surface-Temperature Modulation
by Sara Liparoti, Vito Speranza and Roberto Pantani
Materials 2018, 11(8), 1442; https://doi.org/10.3390/ma11081442 - 15 Aug 2018
Cited by 14 | Viewed by 3360
Abstract
The production by injection molding of polymeric components having micro- and nanometrical surfaces is a complex task. Generally, the accurate replication of micro- and nanometrical features on the polymeric surface during the injection-molding process is prevented by of the low mold temperature adopted [...] Read more.
The production by injection molding of polymeric components having micro- and nanometrical surfaces is a complex task. Generally, the accurate replication of micro- and nanometrical features on the polymeric surface during the injection-molding process is prevented by of the low mold temperature adopted to reduce cooling time. In this work, we adopt a system that allows fast heating of the cavity surface during the time the melt reaches the cavity, and fast cooling after heater deactivation. A nickel insert with micro- and nanofeatures in relief is located on the cavity surface. Replication accuracy is analyzed by Atomic Force Microscopy under different injection-molding conditions. Two grades of polylactic acid with different viscosity have been adopted. The results indicate that the higher the cavity surface temperature is, the higher the replication accuracy is. The viscosity has a significant effect only in the replication of the microfeatures, whereas its effect results are negligible in the replication of nanofeatures, thus suggesting that the interfacial phenomena are more important for replication at a nanometric scale. The evolution of the crystallinity degree on the surface also results in a key factor on the replication of nanofeatures. Full article
(This article belongs to the Special Issue Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties)
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15 pages, 10867 KiB  
Article
Preparation Nano-Structure Polytetrafluoroethylene (PTFE) Functional Film on the Cellulose Insulation Polymer and Its Effect on the Breakdown Voltage and Hydrophobicity Properties
by Jian Hao, Cong Liu, Yanqing Li, Ruijin Liao, Qiang Liao and Chao Tang
Materials 2018, 11(5), 851; https://doi.org/10.3390/ma11050851 - 21 May 2018
Cited by 23 | Viewed by 3998
Abstract
Cellulose insulation polymer is an important component of oil-paper insulation, which is widely used in power transformer. The weight of the cellulose insulation polymer materials is as high as tens of tons in the larger converter transformer. Excellent performance of oil-paper insulation is [...] Read more.
Cellulose insulation polymer is an important component of oil-paper insulation, which is widely used in power transformer. The weight of the cellulose insulation polymer materials is as high as tens of tons in the larger converter transformer. Excellent performance of oil-paper insulation is very important for ensuring the safe operation of larger converter transformer. An effective way to improve the insulation and the physicochemical property of the oil impregnated insulation pressboard/paper is currently a popular research topic. In this paper, the polytetrafluoroethylene (PTFE) functional film was coated on the cellulose insulation pressboard by radio frequency (RF) magnetron sputtering to improve its breakdown voltage and the hydrophobicity properties. X-ray photoelectron spectroscopy (XPS) results show that the nano-structure PTFE functional film was successfully fabricated on the cellulose insulation pressboard surface. The scanning electron microscopy (SEM) and X-ray diffraction (XRD) present that the nanoscale size PTFE particles were attached to the pressboard surface and it exists in the amorphous form. Atomic force microscopy (AFM) shows that the sputtered pressboard surface is still rough. The rough PTFE functional film and the reduction of the hydrophilic hydroxyl of the surface due to the shielding effect of PTFE improve the breakdown and the hydrophobicity properties of the cellulose insulation pressboard obviously. This paper provides an innovative way to improve the performance of the cellulose insulation polymer. Full article
(This article belongs to the Special Issue Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties)
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18 pages, 58492 KiB  
Article
“Skin-Core-Skin” Structure of Polymer Crystallization Investigated by Multiscale Simulation
by Chunlei Ruan
Materials 2018, 11(4), 610; https://doi.org/10.3390/ma11040610 - 16 Apr 2018
Cited by 7 | Viewed by 4759
Abstract
“Skin-core-skin” structure is a typical crystal morphology in injection products. Previous numerical works have rarely focused on crystal evolution; rather, they have mostly been based on the prediction of temperature distribution or crystallization kinetics. The aim of this work was to achieve the [...] Read more.
“Skin-core-skin” structure is a typical crystal morphology in injection products. Previous numerical works have rarely focused on crystal evolution; rather, they have mostly been based on the prediction of temperature distribution or crystallization kinetics. The aim of this work was to achieve the “skin-core-skin” structure and investigate the role of external flow and temperature fields on crystal morphology. Therefore, the multiscale algorithm was extended to the simulation of polymer crystallization in a pipe flow. The multiscale algorithm contains two parts: a collocated finite volume method at the macroscopic level and a morphological Monte Carlo method at the microscopic level. The SIMPLE (semi-implicit method for pressure linked equations) algorithm was used to calculate the polymeric model at the macroscopic level, while the Monte Carlo method with stochastic birth-growth process of spherulites and shish-kebabs was used at the microscopic level. Results show that our algorithm is valid to predict “skin-core-skin” structure, and the initial melt temperature and the maximum velocity of melt at the inlet mainly affects the morphology of shish-kebabs. Full article
(This article belongs to the Special Issue Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties)
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Review

Jump to: Editorial, Research

36 pages, 7209 KiB  
Review
Additive Manufacturing of Metallic and Ceramic Components by the Material Extrusion of Highly-Filled Polymers: A Review and Future Perspectives
by Joamin Gonzalez-Gutierrez, Santiago Cano, Stephan Schuschnigg, Christian Kukla, Janak Sapkota and Clemens Holzer
Materials 2018, 11(5), 840; https://doi.org/10.3390/ma11050840 - 18 May 2018
Cited by 412 | Viewed by 29824
Abstract
Additive manufacturing (AM) is the fabrication of real three-dimensional objects from metals, ceramics, or plastics by adding material, usually as layers. There are several variants of AM; among them material extrusion (ME) is one of the most versatile and widely used. In MEAM, [...] Read more.
Additive manufacturing (AM) is the fabrication of real three-dimensional objects from metals, ceramics, or plastics by adding material, usually as layers. There are several variants of AM; among them material extrusion (ME) is one of the most versatile and widely used. In MEAM, molten or viscous materials are pushed through an orifice and are selectively deposited as strands to form stacked layers and subsequently a three-dimensional object. The commonly used materials for MEAM are thermoplastic polymers and particulate composites; however, recently innovative formulations of highly-filled polymers (HP) with metals or ceramics have also been made available. MEAM with HP is an indirect process, which uses sacrificial polymeric binders to shape metallic and ceramic components. After removing the binder, the powder particles are fused together in a conventional sintering step. In this review the different types of MEAM techniques and relevant industrial approaches for the fabrication of metallic and ceramic components are described. The composition of certain HP binder systems and powders are presented; the methods of compounding and filament making HP are explained; the stages of shaping, debinding, and sintering are discussed; and finally a comparison of the parts produced via MEAM-HP with those produced via other manufacturing techniques is presented. Full article
(This article belongs to the Special Issue Polymer Processing: Modeling and Correlations Finalized to Tailoring the Plastic Part Morphology and Properties)
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