Original Silk Pre-Oxidation Treatment of Carbon Fiber from Coal Tar Pitch

In the preparing process of carbon fiber, the fiber mechanical performance is affected by the pre-oxidation condition. In this paper the pre-oxidation technology condition of the original silk is researched, and the functional group in the molecule and the process of thermal gravimetric of the original silk and pre-oxidized silk are investigated by the method of infrared spectroscopy analysis and thermal gravimetric analysis. The IR analysis shows that associated hydroxyl is disappeared, Ar-H is decreased substantially, and methyl and methylene of the ring structure are changed greatly in the molecule of pre-oxidized silk. The TG analysis shows that the first weight loss temperature is increased, weight loss temperature range is moved to the higher temperature direction, the total weight loss rate is decreased, and weight loss velocity is decreased substantially. The mechanical performance of carbon fiber is affected by the pre-oxidation heating rate. When pre-oxidation heating rate is 1.5°C/min, the breaking strength of carbon fiber is 1195.84Mpa and the Young's modulus is 80Gpa.

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Novel carbon foam composites reinforced with carbon fiber felt developed from inexpensive pitch precursor matrix

Journal of Composite Materials ◽

10.1177/0021998320918353 ◽

2020 ◽

Vol 54 (24) ◽

pp. 3559-3569

Author(s):

Shishobhan Sharma ◽

Rasmika H Patel

Keyword(s):

Carbon Fiber ◽

Elevated Temperatures ◽

Mechanical Response ◽

Mechanical Performance ◽

Coal Tar ◽

Carbon Foam ◽

Petroleum Pitch ◽

Gravimetric Analysis ◽

Carbon Fiber Felt ◽

Carbon Foams

Novel carbon foam composites derived from various pitch precursors have been fabricated and characterized. This paper specifically focuses on developing an effective process for fabricating the carbon foam composites from Polyacrylonitrile (PAN)-based carbon felt as a reinforcement and various readily available pitch matrix such as petroleum pitch, coal tar pitch, and mesophase pitch. The paper endeavors to develop the carbon foam composites and to carry out detailed morphological, thermal, and mechanical characterization. Traditional carbon foams have been known to offer poor mechanical performance, and hence, in this paper, the pitch-based carbon foams were innovatively reinforced with the PAN-based carbon fiber felt. Carbon foam composites were subjected to partial oxidation, and their morphological and mechanical response after the heat treatment was studied thoroughly. Thermal gravimetric analysis and thermal mechanical analysis techniques reveal an appreciable thermo-physical and thermo-mechanical response at elevated temperatures. Also, it was found out that the factors such as volatile content and quinoline insoluble fraction affect the morphology as well as the physical robustness on the composite foams.

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Mechanism and Kinetics Study of Sintering Process for Alumina Recovery from Fly Ash

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.955-959.2824 ◽

2014 ◽

Vol 955-959 ◽

pp. 2824-2830 ◽

Cited By ~ 2

Author(s):

Yong Feng Xiao ◽

Bao Dong Wang ◽

Xiao Ting Liu ◽

Xiao Huan Wang ◽

Li Jun Zhao ◽

...

Keyword(s):

Weight Loss ◽

Fly Ash ◽

Gravimetric Analysis ◽

Kinetics Study ◽

Thermal Gravimetric ◽

Sintering Process ◽

X Ray Diffraction ◽

X Ray ◽

Mechanism And Kinetics ◽

Alumina Recovery

In this paper, the de-silicated fly ash (DSFA) was sintered with soda and calcium oxide. Detailed analysis and characterization was carried out by using thermal gravimetric analysis (TGA) and X-ray diffraction (XRD). Two dominant reactions take place in the sintering process. The kinetics was studied by using Jander mode, and the sintering activation energies were determined based on the weight loss of CO2.

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Pyrolysis Features of Larch Bark and Xylem

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.774-776.503 ◽

2013 ◽

Vol 774-776 ◽

pp. 503-507 ◽

Cited By ~ 1

Author(s):

Hong Shuang Du ◽

Xiang Yu Li ◽

Xue Yong Ren ◽

Yan Xue Han

Keyword(s):

Weight Loss ◽

Heating Rate ◽

Fixed Carbon ◽

Thermo Gravimetric ◽

Thermo Gravimetric Analyzer ◽

Higher Temperature ◽

Tg And Dtg ◽

Benzene Extract ◽

Alcohol Benzene

In this paper, the ultimate, proximate and component analyses of the Daxinganling larch bark and xylem were performed and intercompared respectively. The pyrolysis features of the bark and xylem were analyzed by using the differential thermal thermo-gravimetric analyzer (TG). The influences of heating rate on pyrolysis features were discussed. The results show: (i) the content of H is a little more in the xylem than the bark and the content of ash in the bark is two times of the xylem and the content of fixed carbon in the xylem is two times of the bark. The content of alcohol-benzene extract is significantly more in the bark than the xylem and the glarson lignin in the bark is two times of the xylem but the hemicellulose in the xylem is three times of the bark; (ii) the process of the bark pyrolysis has two pyrolysis areas, but the xylem has a only pyrolysis area, however, the main pyrolysis interval of temperature of the bark and xylem are between 420K to 720K, in which the weight-loss of bark is 87-91% of the full weight-loss and the xylem weight-loss is 91-95% of the full weight-loss. (iii) the DTG peak of the xylem is behind 25 K of bark, and the DTG peak of the bark is-0.47 but the xylem-0.93. (iv) the curves of the TG and DTG move to the side of the higher temperature a bit following the heating rate increased, while the main pyrolysis areas are wider.

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Oxidation of Short Carbon Fiber Reinforced ZrB2-SiC Ceramics under Atmospheric and Oxyacetylene Torch Conditions

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.1753 ◽

2008 ◽

Vol 368-372 ◽

pp. 1753-1755 ◽

Cited By ~ 2

Author(s):

Fei Yu Yang ◽

Xing Hong Zhang ◽

Shan Yi Du

Keyword(s):

Carbon Fiber ◽

Thin Layer ◽

Cross Section ◽

Oxidation Behavior ◽

Gravimetric Analysis ◽

Thermal Gravimetric ◽

Short Carbon Fiber ◽

Average Mass ◽

Sic Ceramics ◽

Short Carbon

The oxidation behavior of ZrB2-20 vol.% SiC (ZS) and ZrB2-20 vol.% SiC containing 20 vol.% short carbon fiber (ZSC) was studied using thermal gravimetric analysis and oxyacetylene torch test. It was shown that weight gains changed from 3.71 wt.% for ZS to 4.57 wt.% for ZSC after heating 10°C /min to 1450°C in air. A thin layer of Si-rich glass and then a depletion layer of SiC was found on the cross section of both materials and carbon fiber of ZSC exposed in air was oxidized. Under oxyacetylene, an average mass loss of 0.8 wt.% for ZS and 0.9 wt.% for ZSC was measured after 180 seconds. After exposure, an oxidized layer with the formation of ZrO2 and SiO2 was found on the surface of both materials. Meanwhile, fiber in the surface of ZSC appeared oxidized and removed.

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Pyrolysis Reactive Behaviors and Kinetic Characteristics of HSW Vitrinite Coal based on Coats-Redfern and DAEM Models

10.21203/rs.3.rs-389404/v1 ◽

2021 ◽

Author(s):

Ruihan Wang ◽

Qiang Wang ◽

Zhuangmei Li ◽

Zhe Liu ◽

Yong Wu ◽

...

Keyword(s):

Activation Energy ◽

Weight Loss ◽

Heating Rate ◽

Loss Rate ◽

Coal Tar ◽

Coal Pyrolysis ◽

Heating Rates ◽

Weight Loss Rate ◽

Weight Loss Behavior ◽

Kinetics Of

Abstract In this work, the weight loss behavior of vitrinite in hongshiwan coal at different heating rates was investigated by thermogravimetric mass spectrometry (TG-MS). Then Coats-Redfern and DAEM models were established to analyze the kinetics of coal pyrolysis. The results show that the weight loss rate of pyrolysis decreased with the increase of heating rate. When the pyrolysis temperature reaches 400–500°C, the weight loss rate reaches the maximum, which is 0.1593, 0.1539, 0.1478 and 0.1414%/°C respectively at the heating rates of 5, 10, 15 and 20°C/min, With the increase of heating rate, the corresponding temperature peaks of the five pyrolysis gases are shifted to the high temperature direction, and the amount of gas escaping is increasing. The trend of higher heating rate delayed the release of volatile compounds was consistent with TG-DTG results. Two kinetic models both prove that the activation energy of coal pyrolysis increases with the increase of temperature. The maximum activation energy occurs between 600 ℃ and 900 ℃, because the multi condensation of coal tar and the re solidification of semi coke will occur in this temperature range.

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Thermal, Mechanical, and Microstructural Study of PBO Fiber during Carbonization

Materials ◽

10.3390/ma12040608 ◽

2019 ◽

Vol 12 (4) ◽

pp. 608 ◽

Cited By ~ 1

Author(s):

Weizhe Hao ◽

Xuejun Zhang ◽

Yanhong Tian

Keyword(s):

Carbon Fiber ◽

Mechanical Performance ◽

Continuous Process ◽

Carbonaceous Material ◽

Inert Atmosphere ◽

Treatment Temperature ◽

Gravimetric Analysis ◽

Graphite Crystallite ◽

Pbo Fiber ◽

Good Heat Resistance

Poly(p-phenylene benzobisoxazole) (PBO) fiber shows fascinating properties including excellent mechanical performance, high crystallinity, and fairly good heat resistance as a kind of polymer fiber. Its properties make it a possible candidate as a precursor of carbon fiber. This paper mainly investigates the possibility of yielding carbon fiber from PBO by direct carbonization using a continuous process and multiple properties of yielded fiber treated under different heat treatment temperature (HTT). The results show that PBO fiber was able to sustain an HTT as high as 1400 °C under the inert atmosphere and that the shape of fiber was still preserved without failure. Using thermal gravimetric analysis (TGA) and TGA coupled with mass spectroscopy (TGA-MS), it was found that a significant mass loss procedure happened around 723.3 °C, along with the emission of various small molecules. The mechanical performance first suffered a decrease due to the rupture of the PBO structure and then slightly increased because of the generating of graphite crystallite based on the broken structure of PBO. It was observed that PBO’s microstructure transformed gradually to that of carbonaceous material, which could be the reason why the change of mechanical performance happened.

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Properties of polyurethane (PUR) films prepared from liquefied wood (LW) and ethylene glycol (EG)

Holzforschung ◽

10.1515/hf-2014-0142 ◽

2015 ◽

Vol 69 (5) ◽

pp. 547-554 ◽

Cited By ~ 9

Author(s):

Wen-Jau Lee ◽

En-Shao Kuo ◽

Chung-Yu Chao ◽

Yu-Pin Kao

Keyword(s):

Molecular Structure ◽

Tensile Strength ◽

Ethylene Glycol ◽

Cryptomeria Japonica ◽

Thermomechanical Analysis ◽

Raw Material ◽

Gravimetric Analysis ◽

Thermal Gravimetric ◽

Liquefied Wood ◽

Higher Temperature

Abstract The wood of Cryptomeria japonica D. Don was liquefied in ethylene glycol (EG) with sulfuric acid (H2SO4) as a catalyst at 150°C for 60 min. The liquefied wood (LW)- and EG-based polyester polyols (EG-Polyest.-ol) were synthesized by reacting LW and EG with adipic acid (AA), respectively. Polyurethane (PUR) resins were made by mixing Polyest.-ol with isocyanate. The results show that LW-Polyest.-ol is a suitable raw material for PUR. The PUR films prepared with LW-Polyest.-ol have higher tensile strength with less elongation at breaking point than that with EG-Polyest.-ol. According to dynamic thermomechanical analysis, the PUR films prepared with EG-Polyest.-ol have a homogeneous molecular structure, whereas a phase separation has been found for those made with LW-Polyest.-ol. Thermal gravimetric analysis showed that the thermal degradation of LW-PUR films only starts at higher temperature than that of EG-PUR.

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Thermal gravimetric analysis of in-situ crosslinked nanocellulose whiskers • poly(methyl vinyl ether-co-maleic acid) • polyethylene glycol

TAPPI Journal ◽

10.32964/tj10.4.29 ◽

2011 ◽

Vol 10 (4) ◽

pp. 29-33

Author(s):

LEE A. GOETZ ◽

AJI P. MATHEW ◽

KRISTIINA OKSMAN ◽

ARTHUR J. RAGAUSKAS

Keyword(s):

Thermal Stability ◽

Polyethylene Glycol ◽

Vinyl Ether ◽

Thermal Gravimetric Analysis ◽

Maleic Acid ◽

Gravimetric Analysis ◽

Thermal Gravimetric ◽

Methyl Vinyl ◽

Methyl Vinyl Ether

The thermal stability and decomposition of in-situ crosslinked nanocellulose whiskers – poly(methyl vinyl ether-co-maleic acid) – polyethylene glycol formulations (PMVEMA-PEG), (25%, 50%, and 75% whiskers) – were investigated using thermal gravimetric analysis (TGA) methods. The thermal degradation behavior of the films varied according to the percent cellulose whiskers in each formulation. The presence of cellulose whiskers increased the thermal stability of the PMVEMA-PEG matrix.

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Fabrication and characterization of hexadecyl acrylate cross-linked phase change microspheres

e-Polymers ◽

10.1515/epoly-2020-0008 ◽

2020 ◽

Vol 20 (1) ◽

pp. 69-75

Author(s):

Haoran Yun ◽

Xingxiang Zhang

Keyword(s):

Phase Change ◽

Smooth Surface ◽

Bone Conduction ◽

Cross Linking ◽

Gravimetric Analysis ◽

Orthopedic Implant ◽

Thermal Gravimetric ◽

Fabrication And Characterization ◽

Fast Release

AbstractMicrospheres with phase change properties were fabricated by polymerization of hexadecyl acrylate (HA) and different cross-linking agents. The samples were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA). The results show that, the samples that added cross-linking agents have a smooth surface and the latent heat of them is different. The experiments show that all of the cross-linked copolymer shells can be made into temperature controlled release microspheres. These materials can be potentially applied in the field of thermal energy storage. β-tricalcium phosphate was encapsulated in microspheres to obtain one with a fast release effect. It will effectively promote bone conduction when these microspheres were implanted into a bone defect. This microsphere can be used for orthopedic implant or coating of instrument in the future.

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