Screening of spinning oils for melt‐spun lignin‐based carbon fiber precursors

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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TG-FTIR Study on the Heat Treatment of Plasticized Melt-Spun PAN Precursors for Carbon Fiber

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.193-194.444 ◽

2012 ◽

Vol 193-194 ◽

pp. 444-447

Author(s):

Bin Yan ◽

Ke Qing Han ◽

Jing Jie Zhang ◽

Dan Wang ◽

Su Ping Liu ◽

...

Keyword(s):

Heat Treatment ◽

Carbon Fiber ◽

Formation Mechanism ◽

Pyrolysis Products ◽

Ftir Study ◽

Melt Spun ◽

Main Decomposition ◽

Decomposition Stages ◽

Pan Fibers

In this paper, the evolution of the gas evolved during the heat treatment of the plasticized melt-spun PAN fibers was investigated by TG-FTIR. TG, DTG and G-S (Gram-Schmidt) curves showed that there were two main decomposition stages during the heat treatment of melt-spun PAN fibers. And the results indicated that the main pyrolysis products were NH3 (966 cm-1 and 932 cm-1), HCN (713 cm-1), H2O (3650 cm-1), CH4 (1305cm-1), CO (2180 cm-1), CO2 (2360 cm-1 and 667 cm-1). The release of NH3 and HCN started at the same temperature 220 °C, which were the main products during the stabilization step. Besides, the formation mechanism of the pyrolysis products is presented in detail.

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Structure and properties of partially cyclized polyacrylonitrile-based carbon fiber-precursor fiber prepared by melt-spun with ionic liquid as the medium of processing

Polymer Engineering & Science ◽

10.1002/pen.24121 ◽

2015 ◽

Vol 55 (12) ◽

pp. 2722-2728 ◽

Cited By ~ 6

Author(s):

Shuping Liu ◽

Keqing Han ◽

Lei Chen ◽

Ying Zheng ◽

Muhuo Yu

Keyword(s):

Ionic Liquid ◽

Carbon Fiber ◽

Precursor Fiber ◽

Structure And Properties ◽

Melt Spun ◽

Carbon Fiber Precursor

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Microstructural Variations in Melt-Spun Rapidly Solidified Ribbons

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117340 ◽

1985 ◽

Vol 43 ◽

pp. 54-55

Author(s):

L. A. Bendersky ◽

W. J. Boettinger

Keyword(s):

Solid State ◽

Processing Parameters ◽

Heat Extraction ◽

Solid State Reactions ◽

Careful Examination ◽

Ion Milling ◽

Melt Spun ◽

Wheel Side ◽

Rapidly Solidified ◽

Heat Extraction Rate

Rapid solidification produces a wide variety of sub-micron scale microstructure. Generally, the microstructure depends on the imposed melt undercooling and heat extraction rate. The microstructure can vary strongly not only due to processing parameters changes but also during the process itself, as a result of recalescence. Hence, careful examination of different locations in rapidly solidified products should be performed. Additionally, post-solidification solid-state reactions can alter the microstructure.The objective of the present work is to demonstrate the strong microstructural changes in different regions of melt-spun ribbon for three different alloys. The locations of the analyzed structures were near the wheel side (W) and near the center (C) of the ribbons. The TEM specimens were prepared by selective electropolishing or ion milling.

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Spherulite Structures in a Melt Spun Fe-Ni Austenitic Steel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117339 ◽

1985 ◽

Vol 43 ◽

pp. 52-53

Author(s):

G. M. Michal ◽

T. K. Glasgow ◽

T. J. Moore

Keyword(s):

Austenitic Steel ◽

Room Temperature ◽

Elevated Temperatures ◽

Large Range ◽

Amorphous Structure ◽

Nucleation And Growth ◽

Ni Alloys ◽

Melt Spun ◽

Crystal Fibers ◽

Rapidly Solidified

Large additions of B to Fe-Ni alloys can lead to the formation of an amorphous structure, if the alloy is rapidly cooled from the liquid state to room temperature. Isothermal aging of such structures at elevated temperatures causes crystallization to occur. Commonly such crystallization pro ceeds by the nucleation and growth of spherulites which are spherical crystalline bodies of radiating crystal fibers. Spherulite features were found in the present study in a rapidly solidified alloy that was fully crysstalline as-cast. This alloy was part of a program to develop an austenitic steel for elevated temperature applications by strengthening it with TiB2. The alloy contained a relatively large percentage of B, not to induce an amorphous structure, but only as a consequence of trying to obtain a large volume fracture of TiB2 in the completely processed alloy. The observation of spherulitic features in this alloy is described herein. Utilization of the large range of useful magnifications obtainable in a modern TEM, when a suitably thinned foil is available, was a key element in this analysis.

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Effects of high pressure on the crystallization of carbon fiber reinforced polyetheretherketone (CF/PEEK) laminate composites

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100177519 ◽

1990 ◽

Vol 48 (4) ◽

pp. 876-877

Author(s):

Hong-Ming Lin ◽

C. H. Liu ◽

R. F. Lee

Keyword(s):

High Pressure ◽

Carbon Fiber ◽

Sample Surface ◽

High Yield ◽

Fiber Reinforced ◽

Laminate Composites ◽

Peek Composite ◽

Continuous Carbon Fiber ◽

Carbon Fiber Reinforced

Polyetheretherketone (PEEK) is a crystallizable thermoplastic used as composite matrix materials in application which requires high yield stress, high toughness, long term high temperature service, and resistance to solvent and radiation. There have been several reports on the crystallization behavior of neat PEEK and of CF/PEEK composite. Other reports discussed the effects of crystallization on the mechanical properties of PEEK and CF/PEEK composites. However, these reports were all concerned with the crystallization or melting processes at or close to atmospheric pressure. Thus, the effects of high pressure on the crystallization of CF/PEEK will be examined in this study.The continuous carbon fiber reinforced PEEK (CF/PEEK) laminate composite with 68 wt.% of fibers was obtained from Imperial Chemical Industry (ICI). For the high pressure experiments, HIP was used to keep these samples under 1000, 1500 or 2000 atm. Then the samples were slowly cooled from 420 °C to 60 °C in the cooling rate about 1 - 2 degree per minute to induce high pressure crystallization. After the high pressure treatment, the samples were scanned in regular DSC to study the crystallinity and the melting temperature. Following the regular polishing, etching, and gold coating of the sample surface, the scanning electron microscope (SEM) was used to image the microstructure of the crystals. Also the samples about 25mmx5mmx3mm were prepared for the 3-point bending tests.

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Enhanced performance of supercapacitors by constructing a “mini parallel-plate capacitor” in an electrode with high dielectric constant materials

Journal of Materials Chemistry A ◽

10.1039/d0ta04364h ◽

2020 ◽

Vol 8 (32) ◽

pp. 16661-16668

Author(s):

Huayao Tu ◽

Shouzhi Wang ◽

Hehe Jiang ◽

Zhenyan Liang ◽

Dong Shi ◽

...

Keyword(s):

Dielectric Constant ◽

Carbon Fiber ◽

Parallel Plate ◽

Sandwich Structure ◽

High Dielectric Constant ◽

Parallel Plate Capacitor ◽

Plate Capacitor ◽

Fiber Metal ◽

High Dielectric ◽

Mini Plate

The carbon fiber/metal oxide/metal oxynitride layer sandwich structure is constructed in the electrode to form a mini-plate capacitor. High dielectric constant metal oxides act as dielectric to increase their capacitance.

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