Preparation and evaluation of isotropic and mesophase pitch-based carbon fibers using the pelletizing and continuous spinning process

The purpose of this study is to investigate the potential of using a pelletized pitch in a continuous process for the economical preparation of large-scale pitch-based carbon fibers. The pitch was pelletized before spinning because the pitch powder can agglomerate in the feed throat of a screw extruder, which can render uniform heating difficult. Using the pelletized pitch in a single-screw extruder spinning apparatus, the pitch fiber can be spun to a great length as long as the amount of pitch pellets is sufficient. To evaluate the benefits of using pitch pellets in the continuous carbon fiber spinning process, isotropic and mesophase pitch fibers were prepared by both the conventional batch process using pitch powder and continuous process using pitch pellets. Even with a huge difference in the thermal energy used, the carbon fibers prepared using the pelletized-pitch-based continuous process had better tensile properties than those prepared using the conventional process. This suggests that the continuous process using pitch pellets has the potential to be an economical large-scale process for carbon fiber preparation.

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Feasibility and Characterization of Large-Scale Additive Manufacturing With Long Fiber Reinforced Composites

Volume 1: Additive Manufacturing; Advanced Materials Manufacturing; Biomanufacturing; Life Cycle Engineering; Manufacturing Equipment and Automation ◽

10.1115/msec2020-8257 ◽

2020 ◽

Author(s):

Aditya R. Thakur ◽

Ming C. Leu ◽

Xiangyang Dong

Keyword(s):

Additive Manufacturing ◽

Carbon Fiber ◽

Carbon Fibers ◽

Large Scale ◽

Flexural Modulus ◽

High Deposition Rate ◽

Reinforced Composites ◽

Fiber Reinforced ◽

Continuous Fiber ◽

Long Carbon Fibers

Abstract A new additive manufacturing (AM) approach to fabricate long fiber reinforced composites (LFRC) was proposed in this study. A high deposition rate was achieved by the implementation of a single-screw extruder, which directly used thermoplastic pellets and continuous fiber tows as feedstock materials. Thus, the proposed method was also used as a large-scale additive manufacturing (LSAM) method for printing large-volume components. Using polylactic acid (PLA) pellets and continuous carbon fiber tows, the feasibility of the proposed AM method was investigated through printing LFRC samples and further demonstrated by fabricating large-volume components with complex geometries. The printed LFRC samples were compared with pure thermoplastic and continuous fiber reinforced composite (CFRC) counterparts via mechanical tests and microstructural analyses. With comparable flexural modulus, the flexural strength of the LFRC samples was slightly lower than that of the CFRC samples. An average improvement of 28% in flexural strength and 50% in flexural modulus were achieved compared to those of pure PLA parts, respectively. Discontinuous long carbon fibers, with an average fiber length of 20.1 mm, were successfully incorporated into the printed LFRC samples. The carbon fiber orientation, distribution of carbon fiber length, and dispersion of carbon fiber as well as porosity were further studied. The carbon fibers were highly oriented along the printing direction with a relatively uniformly distributed fiber reinforcement across the LFRC cross section. With high deposition rate (up to 0.8 kg/hr) and low material costs (< $10/kg), this study demonstrated the potentials of the proposed printing method in LSAM of high strength polymer composites reinforced with long carbon fibers.

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Characteristics of Mesophase Pitch-Based Carbon Fibers as Anode Materials for Lithium Secondary Cells

MRS Proceedings ◽

10.1557/proc-393-357 ◽

1995 ◽

Vol 393 ◽

Cited By ~ 2

Author(s):

Toshio Tamaki

Keyword(s):

Carbon Fiber ◽

Electrochemical Properties ◽

Carbon Fibers ◽

Discharge Capacity ◽

Anode Materials ◽

Mesophase Pitch ◽

Good Efficiency ◽

Heat Treated ◽

Initial Charge ◽

Discharge Efficiency

ABSTRACTMesophase pitch-based Carbon Fibers(MPCF) have been investigated as anode materials for lithium secondary cells by examining their physical and electrochemical properties. Discharge capacity and initial charge-discharge efficiency of the materials were studied in relation to the heat treatment temperatures of MPCF. Carbon fiber which was heat treated at about 3,000’C gave the highest discharge capacity(over 300mAh/g), good efficiency (92%) and superior current capability (600mA/g). Carbon fiber heat treated at less than 1,000·C, also has superior discharge capacity(over 500mAh/g) at the first cycle, however efficiency was relatively low. Some of the relationships between structure of MPCF and electrochemical properties are discussed below.

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Synthesis and Processing of Melt Spun Materials from Esterified Lignin with Lactic Acid

Applied Sciences ◽

10.3390/app9245361 ◽

2019 ◽

Vol 9 (24) ◽

pp. 5361 ◽

Cited By ~ 2

Author(s):

Panagiotis Goulis ◽

Ioannis Kartsonakis ◽

George Konstantopoulos ◽

Costas Charitidis

Keyword(s):

Lactic Acid ◽

Carbon Fiber ◽

Carbon Fibers ◽

Thermal Processing ◽

Large Scale ◽

Value Added ◽

Poly Lactic Acid ◽

Scale Production ◽

Fibrous Materials ◽

Melt Spun

In this study, the carbon fiber manufacturing process is investigated, using high-density polyethylene (HDPE) and esterified lignin either with lactic acid (LA) or with poly(lactic acid) (PLA) as precursors. More specifically, lignin was modified using either LA or PLA in order to increase its chemical affinity with HDPE. The modified compounds were continuously melt spun to fibrous materials by blending with HDPE in order to fabricate a carbon fiber precursor. The obtained products were characterized with respect to their morphology, as well as their structure and chemical composition. Moreover, an assessment of both physical and structural transformations after modification of lignin with LA and PLA was performed in order to evaluate the spinning ability of the composite fibers, as well as the thermal processing to carbon fibers. This bottom–up approach seems to be able to provide a viable route considering large scale production in order to transform lignin in value-added product. Tensile tests revealed that the chemical lignin modification allowed an enhancement in its spinning ability due to its compatibility improvement with the commercial low-cost and thermoplastic HDPE polymer. Finally, stabilization and carbonization thermal processing was performed in order to obtain carbon fibers.

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Modification Process of Carbon Fiber Reinforcement for Aluminum Matrix Composite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.560-561.899 ◽

2012 ◽

Vol 560-561 ◽

pp. 899-905

Author(s):

Xiao Fang Liu ◽

Ping Li ◽

Zhong Xia Liu

Keyword(s):

Carbon Fiber ◽

Carbon Fibers ◽

Matrix Composite ◽

Large Scale ◽

Ph Value ◽

Aluminum Matrix ◽

Fiber Reinforcement ◽

Aluminum Matrix Composite ◽

Modification Process ◽

Carbon Fiber Reinforcement

Modification process of carbon fiber reinforcement was investigated so as to produce aluminum matrix composite on a large scale. A series of pretreatment technologies could acquire chemical deposition silver, which became the base of copperplating on the surface of carbon fibers. The optimum conditions of electroless plating copper, including components, adding amount of carbon fibers, temperature, pH value, and mixing method, were determined to obtain a perfect copper layer on the surface of carbon fibers. The control of copper deposition and repeating utilization of many technology solutions were realized to reduce the costs. The results laid a foundation of mass production for carbon fiber reinforced aluminum matrix composite.

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Mesophase pitch-based carbon fiber spinning through a filter assembly and the microstructure evolution mechanism

Journal of Materials Science ◽

10.1007/s10853-013-7692-z ◽

2013 ◽

Vol 49 (1) ◽

pp. 191-198 ◽

Cited By ~ 14

Author(s):

Yanbo Yao ◽

Jianming Chen ◽

Ling Liu ◽

Yanming Dong ◽

Anhua Liu

Keyword(s):

Carbon Fiber ◽

Microstructure Evolution ◽

Fiber Spinning ◽

Mesophase Pitch ◽

Evolution Mechanism

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A Comparative Study of Pellet-Based Extrusion Deposition of Short, Long, and Continuous Carbon Fiber Reinforced Polymer Composites for Large-Scale Additive Manufacturing

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4049646 ◽

2021 ◽

pp. 1-32

Author(s):

John M. Pappas ◽

Aditya R. Thakur ◽

Ming C. Leu ◽

Xiangyang Dong

Keyword(s):

Additive Manufacturing ◽

Carbon Fiber ◽

Carbon Fibers ◽

Large Volume ◽

Fiber Length ◽

Large Scale ◽

Fiber Reinforced Polymer ◽

Fiber Reinforced ◽

Continuous Fiber ◽

Reinforced Polymer

Abstract Pellet-based extrusion deposition of carbon fiber reinforced composites at high material deposition rates has recently gained much attention due to its applications in large-scale additive manufacturing. The mechanical and physical properties of large-volume components largely depend on their reinforcing fiber length. However, very few studies have been done thus far to have a direct comparison of additively fabricated composites reinforced with different carbon fiber lengths. In this study, a new additive manufacturing (AM) approach to fabricate long fiber reinforced polymer (LFRP) was first proposed. A pellet-based extrusion deposition method was implemented, which directly used thermoplastic pellets and continuous fiber tows as feedstock materials. Discontinuous long carbon fibers, with an average fiber length of 20.1 mm, were successfully incorporated into printed LFRP samples. The printed LFRP samples were compared with short fiber reinforced polymer (SFRP) and continuous fiber reinforced polymer (CFRP) counterparts through mechanical tests and microstructural analyses. The carbon fiber dispersion, distribution of carbon fiber length and orientation, and fiber wetting were studied. As expected, a steady increase in flexural strength was observed with increasing fiber length. The carbon fibers were highly oriented along the printing direction. A more uniformly distributed discontinuous fiber reinforcement was found within printed SFRP and LFRP samples. Due to decreased fiber impregnation time and lowered impregnation rate, the printed CFRP samples showed a lower degree of impregnation and worse fiber wetting conditions. The feasibility of the proposed AM methods was further demonstrated by fabricating large-volume components with complex geometries.

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Rheology of Polyacrylonitrile/Lignin Blends in Ionic Liquids under Melt Spinning Conditions

Molecules ◽

10.3390/molecules24142650 ◽

2019 ◽

Vol 24 (14) ◽

pp. 2650 ◽

Cited By ~ 1

Author(s):

Jinxue Jiang ◽

Keerthi Srinivas ◽

Alper Kiziltas ◽

Andrew Geda ◽

Birgitte K. Ahring

Keyword(s):

Carbon Fiber ◽

Carbon Fibers ◽

Melt Spinning ◽

Lower Cost ◽

Biomass Pretreatment ◽

Limited Success ◽

Spinning Process ◽

Physical Interactions ◽

Butyric Anhydride ◽

Newtonian Behavior

Lignin, while economically and environmentally beneficial, has had limited success in use in reinforcing carbon fibers due to harmful chemicals used in biomass pretreatment along with the limited physical interactions between lignin and polyacrylonitrile (PAN) during the spinning process. The focus of this study is to use lignin obtained from chemical-free oxidative biomass pretreatment (WEx) for blending with PAN at melt spinning conditions to produce carbon fiber precursors. In this study, the dynamic rheology of blending PAN with biorefinery lignin obtained from the WEx process is investigated with the addition of 1-butyl-3-methylimidazolium chloride as a plasticizer to address the current barriers of developing PAN/lignin carbon fiber precursors in the melt-spinning process. Lignin was esterified using butyric anhydride to reduce its hydrophilicity and to enhance its interactions with PAN. The studies indicate that butyration of the lignin (BL) increased non-Newtonian behavior and decreased thermo-reversibility of blends. The slope of the Han plot was found to be around 1.47 for PAN at 150 °C and decreased with increasing lignin concentrations as well as temperature. However, these blends were found to have higher elasticity and solution yield stress (47.6 Pa at 20%wt BL and 190 °C) when compared to pure PAN (5.8 Pa at 190 °C). The results from this study are significant for understanding lignin–PAN interactions during melt spinning for lower-cost carbon fibers.

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Cytocompatibility of Carbon Nanofiber Materials for Neural Applications

MRS Proceedings ◽

10.1557/proc-774-o7.35 ◽

2003 ◽

Vol 774 ◽

Author(s):

Janice L. McKenzie ◽

Michael C. Waid ◽

Riyi Shi ◽

Thomas J. Webster

Keyword(s):

Carbon Fiber ◽

Surface Energy ◽

Carbon Nanofibers ◽

Carbon Fibers ◽

Carbon Nanofiber ◽

Fiber Composite ◽

Scar Tissue ◽

Pc 12 Cells ◽

Low Surface Energy ◽

Poly Carbonate

AbstractSince the cytocompatibility of carbon nanofibers with respect to neural applications remains largely uninvestigated, the objective of the present in vitro study was to determine cytocompatibility properties of formulations containing carbon nanofibers. Carbon fiber substrates were prepared from four different types of carbon fibers, two with nanoscale diameters (nanophase, or less than or equal to 100 nm) and two with conventional diameters (or greater than 200 nm). Within these two categories, both a high and a low surface energy fiber were investigated and tested. Astrocytes (glial scar tissue-forming cells) and pheochromocytoma cells (PC-12; neuronal-like cells) were seeded separately onto the substrates. Results provided the first evidence that astrocytes preferentially adhered on the carbon fiber that had the largest diameter and the lowest surface energy. PC-12 cells exhibited the most neurites on the carbon fiber with nanodimensions and low surface energy. These results may indicate that PC-12 cells prefer nanoscale carbon fibers while astrocytes prefer conventional scale fibers. A composite was formed from poly-carbonate urethane and the 60 nm carbon fiber. Composite substrates were thus formed using different weight percentages of this fiber in the polymer matrix. Increased astrocyte adherence and PC-12 neurite density corresponded to decreasing amounts of the carbon nanofibers in the poly-carbonate urethane matrices. Controlling carbon fiber diameter may be an approach for increasing implant contact with neurons and decreasing scar tissue formation.

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