Pitch compositions for spinning into carbon products and methods relating thereto

Abstract

Pitch compositions suitable for spinning can include: a pitch having a softening point temperature (T sp ) of 400°C or less and an oxidation onset temperature (OOT) that is at least 10°C lower than T sp at a temperature ramp rate of 10°C / min. Carbon fibers can include: carbon fibers made from a pitch composition, wherein the pitch composition includes: a pitch having a softening point temperature (T sp ) of 400°C or less and an oxidation onset temperature (OOT) that is at least 10°C lower than T sp at a temperature ramp rate of 10°C / min.

Description

Invention Field

[0001] This application relates to pitch compositions, methods for their preparation, and uses. Additionally, this application relates to pitch compositions suitable for spinning into carbon fibers, which possess improved stabilization properties. Background of the Invention

[0003] In recent years, the carbon fiber industry has experienced steady growth to meet the needs of numerous industries, including textiles, automotive, aerospace, high-performance underwater containers, aircraft, sporting goods, construction, military, wind power, energy storage applications, fireproofing materials, carbon-carbon composites, and various insulation and sealing materials used in structural and road construction, turbine blades, lightweight cylinders and pressure vessels, offshore mooring lines and drilling risers, and medical applications. The aforementioned non-limiting properties of carbon fiber make it suitable for high-performance applications: high bulk modulus and tensile modulus (depending on the morphology of the carbon fiber), high electrical conductivity and thermal conductivity, etc. Therefore, carbon fiber has become an important reinforcing material in advanced composite materials. Despite the outstanding performance of carbon fiber materials, its high cost limits its application and widespread use. Therefore, developing low-cost technologies has become a major challenge for researchers and key manufacturers.

[0004] Carbon fibers can be prepared from pitch, which can be derived, for example, from petroleum, coal tar, biomass tar, or from the acid-catalyzed oligomerization of small molecules (e.g., naphthalene). Carbon fibers can be prepared as follows: melt spinning; stabilization; carbonization; and graphitization. In the melt spinning process, the pitch is heated to a sufficiently high temperature to melt it and its viscosity is reduced so that the heated pitch can pass through the spinneret. The carbon fibers obtained from the pitch can then be wound onto a spinning spool or laid up as a fibrous material. Pitch is considered suitable for spinning based on many different requirements that must be met. Non-limiting examples of these requirements include: a) softening point (T0). sp a) Low enough to enable melt spinning without chemical degradation; b) Low volatile content to minimize carbon fiber breakage during spinning; c) Ability of pitch to be spun into carbon fibers; d) Pitch having sufficient mesophase to obtain fibers with the desired modulus; and e) Pitch having sufficiently low reactivity at temperatures below its softening point to achieve optimal stability in air or other reactive media.

[0005] In particular, the carbon fiber stabilization process is one of the most critical processes in producing high-quality and low-cost carbon fibers. The relationship between stabilization conditions and the mechanical properties of carbonized fibers is important because the stabilization process chemically alters the spun fibers at the atomic level prior to carbonization. Many factors influence the stabilization process, including the properties of the pitch, temperature, gaseous environment, and time. Therefore, it remains necessary to determine the optimal stabilization conditions for carbon fibers.

[0006] Therefore, it is highly desirable to evaluate and establish methods for assessing and establishing the compositional properties of pitch directly related to spinning and stabilization processes, as well as methods for preparing pitch compositions with properties designed for excellent stability. Invention Overview

[0008] This application relates to pitch compositions, methods for their preparation, and uses. Additionally, this application relates to pitch compositions suitable for spinning into carbon fibers, which possess improved stabilization properties.

[0009] The pitch composition suitable for spinning described in this application may contain pitch having a softening point temperature of 400°C or lower (T0). sp ) and has a higher temperature variation than T at a temperature ramp rate of 10℃ / min. sp Oxidation onset temperature (OOT) at least 10°C lower.

[0010] The carbon fiber of this application may comprise: carbon fiber obtained from a pitch composition, wherein the pitch composition contains pitch having a softening point temperature of 400°C or lower (T0). sp ) and has a higher temperature ratio than T at a temperature change rate of 10℃ / min sp Oxidation onset temperature (OOT) at least 10°C lower.

[0011] The carbon fiber composite material of this application may comprise: a matrix material; and carbon fibers obtained from a pitch composition, wherein the pitch composition comprises pitch having a softening point temperature of 400°C or lower. sp ) and has a higher temperature ratio than T at a temperature change rate of 10℃ / min sp Oxidation onset temperature (OOT) at least 10°C lower.

[0012] The method of this application may include: providing asphalt having a softening point temperature (T0.05) of 400°C or lower. sp ) and has a ratio of T sp The oxidation initiation temperature (OOT) is at least 10°C lower than that of the pitch; the pitch is spun to prepare carbon fibers; and the carbon fibers are stabilized in the presence of air or other reactive gases, thereby by heating the carbon fibers to a temperature lower than that of the pitch. sp Stable carbon fibers are obtained at temperatures at least 10°C lower.

[0013] The method of this application may include: introducing a hydrocarbon feed into one or more reaction zones to produce a reaction effluent, wherein the reaction effluent is fed into one or more separation zones to classify the reaction effluent, thereby obtaining an asphalt product, wherein the asphalt product has a higher T than the hydrocarbon feed. sp Higher T spand has a higher T than asphalt products at a temperature change rate of 10℃ / min. sp OOT at least 10°C lower. Brief description of the attached diagram

[0015] The following figures are provided to illustrate certain aspects of the invention and should not be construed as exclusionary embodiments. It will be understood by those skilled in the art that the subject matter disclosed herein can be considered in variations, changes, combinations, and equivalents in form and function, and possesses the benefits disclosed herein.

[0016] Figure 1 It is a differential scanning calorimetry (DSC) curve showing how the heat flux (W / g) of asphalt in air changes with temperature (°C).

[0017] Figure 2A It is a graph depicting the oxidation kinetics of vacuum residue from hydrotreated steam cracker tar (HDT SCT) and mesophase pitch formed from said HDT SCT, expressed as the natural logarithm of the apparent rate ln(rate of change) relative to (1 / OOT), where OOT corresponds to the oxidation initiation temperature. Figure 2B It describes the apparent rate constant (k) predicted based on the activation parameters determined by kinetic analysis. obs ,s -1 At the asphalt softening point T sp The graphs at different temperatures are used as the difference (T). 实际 –T sp )draw.

[0018] Figure 3 It is a differential scanning calorimetry (DSC) curve showing the change of heat flux (W / g) of asphalt in air as a function of temperature (°C) in an open pan.

[0019] Figure 4A It is a differential scanning calorimetry (DSC) curve showing the change of heat flux (W / g) of various asphalts in air and in an open pan as a function of temperature (°C). Figure 4B It is a differential scanning calorimetry (DSC) curve showing the change of heat flux (W / g) of various asphalts in air as a function of temperature (°C) in an open pan.

[0020] Figure 5 It is a differential scanning calorimetry (DSC) curve showing the change of heat flux (W / g) of asphalt as a function of temperature (°C) in an open pan under air and nitrogen.

[0021] Figure 6 It is a thermogravimetric analysis (TGA) graph showing how the weight loss of various asphalts changes with temperature (°C).

[0022] Figure 7 This shows the weight loss of various asphalts with respect to the volatile formation temperature and softening point (T) as measured and recorded by TGA. sp Thermogravimetric analysis (TGA) plot showing the variation of temperature difference (ΔT, °C) between the two points. Invention Details

[0024] This application relates to pitch compositions, methods for their preparation, and uses. Additionally, this application relates to pitch compositions suitable for spinning into carbon fibers, which possess improved stabilization properties.

[0025] The embodiments disclosed herein include a pitch composition suitable for use in spinning, comprising pitch having a softening point temperature of 400°C or lower (T0). sp ) and has a higher temperature ratio than T at a temperature change rate of 10℃ / min sp The oxidation initiation temperature (OOT) should be at least 10°C lower than the OOT temperature. The "softening point" (T) used in this article... sp The softening point refers to the temperature or temperature range at which the material softens. Here, the softening point is determined using a METTLER TOLEDO dropping point instrument, such as the METTLERTOLEDO DP70, following a procedure similar to ASTM D3104. For asphalt with a softening point above 180°C, testing is performed under nitrogen protection.

[0026] Advantageously, this composition provides improved stabilizing effects for the production of carbon fibers, and for example, improves tensile strength and tensile modulus. This composition can also provide improved spinning. Because of these improved properties, the pitch composition described herein can be used to produce higher quality carbon products. Additionally, determining which pitch composition has the desired difference (T) is crucial. sp -OOT), which allows for the determination of whether the pitch composition is suitable for spinning, and whether the corresponding carbon fibers obtained from said pitch composition can be effectively stabilized. When the difference (T) sp When the difference (T) is negative, it indicates that the fiber will melt before it is stabilized by reacting with air. sp When -OOT is positive, it indicates that the asphalt can react at a temperature lower than its softening point. Alternatively, if the stabilization kinetics are determined by varying the rate of temperature change, the apparent rate constant (k) at different temperatures can be calculated. app This allows for evaluation relative to the asphalt softening point (TT). sp The apparent rate constant in relation to ().

[0027] The term "initial oxidation temperature" used in this article is a relative measure of the degree of oxidative stability of a material evaluated at a given heating rate and in an oxidizing environment, such as oxygen; the higher the OOT value, the more stable the material. OOT can be detected by DSC technology. Several detection methods can be used to determine the oxidative properties of hydrocarbons under linear heating rate conditions by DSC or differential pressure scanning calorimetry (PDSC), which can be used for those hydrocarbons that undergo exothermic oxidation in their analytical form. Here, OOT is detected according to the ASTM E2009 standard test method.

[0028] This application also relates to a method for producing carbon fiber from the above-described pitch composition, wherein the pitch composition comprises pitch having a softening point temperature of 400°C or lower (T0). sp ) and has a lower softening point T than asphalt at a temperature change rate of 10℃ / min. sp The oxidation initiation temperature (OOT) is at least 10°C lower than that of the asphalt composition. A method for producing carbon fibers from the above-mentioned pitch composition includes spinning a single pitch, a combination of two pitches, or a blend of at least two pitches to obtain carbon fibers containing the aforementioned pitches; and stabilizing the carbon fibers in the presence of air or other reactive matrices, thereby heating the carbon fibers to a temperature lower than that of the pitch by a specific temperature (T). sp Stable carbon fibers can be obtained at lower temperatures, ranging from -50°C to +100°C OOT. Alternatively, the stabilization kinetics can be estimated by varying the rate of temperature change and determining the OOT for each temperature. Fitting the data to a hypothetical first-order reaction yields activation parameters, which can be used to estimate the apparent rate constant (k) over a range of temperatures. app The apparent rate constant (k) at the asphalt softening point can be determined. app (TT) sp =0). This application also relates to a method for producing carbon fibers from the above-described pitch composition, the pitch composition comprising pitch having a softening point temperature of 400°C or lower (T). sp ) and in T sp (TT sp The apparent rate constant (k) when = 0) app (greater than 1x10) -03 s -1 .

[0029] This application also relates to a method comprising the following process: providing asphalt having a softening point temperature (T0.05) of 400°C or lower. sp ) and has a higher temperature ratio than T at a temperature change rate of 10℃ / min spThe oxidation initiation temperature (OOT) is at least 10°C lower than that of the pitch; the pitch is spun to obtain carbon fibers; and the carbon fibers are stabilized in the presence of air or other reactive matrices, thereby by heating the carbon fibers to a temperature lower than that of the pitch. sp Stable carbon fibers are obtained at temperatures at least 10°C lower. The pitch can have a mesophase content of 5 vol% or less based on the total pitch volume. Alternatively, the pitch can have a mesophase content of 5 vol% to 100 vol% based on the total pitch volume. Furthermore, the pitch can be [specified] from 0 to 100 [specified] s. -1 It exhibits tensile viscosities ranging from 5 Pa·s to 500,000 Pa·s at tensile strain rates. Asphalt can be processed at TT... sp It has an apparent rate constant (k) for oxidation in air at ≤0℃. app Greater than 0.001s -1 In at least one embodiment, the bitumen is at the spinning temperature and / or between 0 and 100 s. -1 It has tensile viscosities ranging from 5 Pa·s to 500,000 Pa·s at tensile strain rates.

[0030] This application also relates to a process comprising: introducing a hydrocarbon feed into one or more reaction zones to produce a reaction effluent, wherein the reaction effluent may be fed into one or more separation zones to classify the reaction effluent, thereby obtaining an asphalt product, wherein the asphalt product may have a Tg ratio greater than that of the hydrocarbon feed. sp Higher T sp and has a higher temperature variation than asphalt at a temperature change rate of 10℃ / min. sp OOT at least 10°C lower. Hydrocarbon feedstock can be selected from the following group: crude oil, fluidized bed catalytic cracking (FCC) main column bottoms (MCB), steam cracker tar, hydrotreated MCB, hydrotreated steam cracker tar, vacuum residue, atmospheric residue, reformate, naphthalene, coal tar, coal tar pitch, vacuum gas oil, distillate, petroleum bitumen, or any of the above feedstocks in a hydrotreated form. Separation zones may include flash tanks, distillation columns, chromatographic separation, membrane filtration, or deasphalting operations. Reaction zones may include fixed-bed reactors, slurry reactors, tubular reactors, continuous stirred tank reactors, batch reactors, or semi-batch reactors. Bituminous material can have a T value in the range of 100°C to 400°C. sp Additionally, asphalt can have an intermediate phase content of about 5% by volume or more. Alternatively, asphalt can have an intermediate phase content of less than 5% by volume.

[0031] The carbon fibers can be used in textile or molded products to improve the strength, stiffness, electrical conductivity, and thermal conductivity of the articles. In addition to fiber products, the carbon fibers can also be introduced into polymer matrices to create molded or printed products. Fibers and other carbon products are described in more detail below.

[0032] Definition and testing methods

[0033] The new naming rules for the periodic table of elements, as described in Chemical and Engineering News, 63(5), 27(1985), are adopted.

[0034] All numerical values ​​mentioned in the detailed description and claims herein may be modified with “about” or “approximately” to take into account experimental errors and variations that would be expected by a person skilled in the art. Unless otherwise stated, ambient temperature (room temperature) is about 18°C ​​to about 20°C.

[0035] Unless otherwise expressly stated, the singular forms “a,” “an,” and “the” used in the specification and claims include the plural forms.

[0036] In this document, the term “and / or” as used in phrases such as “A and / or B” is intended to include “A and B”, “A or B”, and “A” and “B”.

[0037] When the term "between" is used in this article to indicate a range, the term covers the endpoints of that range. That is, "between 2% and 10%" means 2%, 10%, and all percentages between these values.

[0038] The numerical ranges used in this article include numbers within that range. For example, the numerical range "1 wt% to 10 wt%" includes 1 wt% and 10 wt% of that range, as well as all values ​​within that range.

[0039] The term "independently" when referring to the selection of multiple items from a given set of Markush options means that the choice of the first item does not necessarily affect any choice of the second or subsequent items. In other words, within a given set of Markush options, independent selection of multiple items means that the items can be the same as or different from each other.

[0040] The following abbreviations are used in this article: DSC is Differential Scanning Calorimetry; TGA is Thermogravimetric Analysis; T g It is the glass transition temperature, T sp 1 is the softening point temperature; 2 is the oxidation initiation temperature; 3 is the MCRT (Mearting and Calcification Test for Trace Carbon Residues); 4 is the revolutions per minute; 5 is the Pascal-second; 6 is the watts per gram; 7 is the weight percentage; 8 is the mole percentage; 9 is the volume percentage; 10 is the psig (pounds per square inch); 10 is the weight hourly space velocity.

[0041] The "Trace Carbon Residue Test," also known as the "MCRT," is a standard test method (trace method) for detecting carbon residues. The carbon residue values ​​for various petroleum materials are used to estimate the material's tendency to form carbonaceous deposits under degradation conditions similar to those used in the test method, and can be used to guide the production of certain materials. However, careful interpretation of the results is required. This test method involves detecting the amount of carbon residue formed after the evaporation and pyrolysis of petroleum materials under specific conditions, and is intended to provide some indication of the corresponding coke formation tendency of the material. In this paper, the MCRT is performed according to the ASTM D4530-15 standard test method.

[0042] As used herein, the term "blend" refers to a mixture of two or more types of asphalt. Blends can be obtained, for example, by solution blending, melt blending in a heated mixer, physical blending of liquid asphalt with different solid asphalts, or physical blending of multiple asphalts in solid form. Suitable solvents for solution blending may include benzene, toluene, naphthalene, xylene, pyridine, quinoline, aromatic fractions from refining operations or chemical processes, such as decanting oil, reforming products, tar distillation fractions, etc. Solution blending, solid blending, and / or melt blending can be carried out at temperatures from about 20°C to about 400°C.

[0043] Unless otherwise stated, all numerical values ​​used in this specification and related claims to indicate the amount of an ingredient, properties such as molecular weight, reaction conditions, etc., should be understood to be modified with "about" in all cases. Therefore, unless stated to the contrary, the numerical parameters mentioned in the following specification and appended claims are approximate values ​​and may vary depending on the desired performance sought in the embodiments described herein. Without at least attempting to limit the application of equivalent forms to the scope of the claims, each numerical parameter should be constructed at least based on the reported significant figures and using conventional rounding rules.

[0044] One or more exemplary embodiments incorporated herein are described. For clarity, not all features of the actual implementation are described or shown in this application. It should be understood that in developing an actual implementation incorporated into the embodiments of this application, many decisions need to be made regarding the actual implementation to achieve the developer's objectives, such as compliance with system-related regulations, business-related regulations, government-related regulations, and other regulations that frequently change during implementation. While the developer's efforts may be time-consuming, these efforts remain conventional methods for those skilled in the art and have the benefits described herein.

[0045] Although this document describes compositions and methods in the form of “comprising” and “having” various components or steps, these compositions and methods may also be described as “consisting substantially of various components or steps” or “comprised of various components or steps”.

[0046] Asphalt composition

[0047] As used herein, the term "asphalt" refers to a complex mixture of high-boiling-point aromatic compounds, primarily aromatic and alkyl-substituted, which are glassy at ambient temperatures and have softening points above 50°C. These aromatic compounds are primarily hydrocarbons, but heteroatoms and trace metals may be present within these materials. Asphalt can solidify without crystallization upon cooling from a melt. Asphalt can include petroleum bitumen, coal tar bitumen, natural bitumen, bitumen contained as a byproduct in the naphtha cracking industry, bitumen with a high carbon content obtained from petroleum bitumen, and other substances with bituminous properties obtained as products in various industrial production processes. Asphalt exhibits a wide softening temperature range and is generally derived from petroleum, coal tar, plants, or small-molecule catalytic oligomerization (e.g., acid-catalyzed oligomerization). Asphalt can also be called tar, geoasphalt, or tar. When bitumen is produced from plants, it is also called resin. Various bitumens can be obtained as products in the gas oil or naphtha cracking industries, which, as carbonaceous residues, consist of a complex mixture of major aromatic organic compounds that are solid at room temperature and exhibit a wide softening temperature range. Therefore, bitumen can be obtained from the heat treatment and distillation of petroleum fractions. "Petroleum bitumen" refers to residual carbonaceous materials obtained from the distillation, deasphalting, or other separation processes of crude oil, from the catalytic cracking of petroleum distillates, and from other heat treatment or catalytic processes of substances derived from crude oil. "Coal tar bitumen" refers to materials obtained through the distillation of coal.

[0048] The bitumen compositions disclosed herein can be obtained from hydrocarbon feedstocks comprising one or more of the following: straight-run naphtha, coking naphtha, steam-cracked naphtha, catalytically cracked naphtha, gas oil, steam-cracked gas oil, coking gas oil, catalytically cracked gas oil, steam-cracked tar, vacuum gas oil, heavy coking gas oil, residual reformate, Fischer-Tropsch liquids, Fischer-Tropsch gases, natural gasoline, distillate oils, heating oils, injection fuels, diesel, kerosene, gasoline, atmospheric tubular still bottom oil, vacuum tubular still feedstock including bottom oil, wide-boiling-range naphtha to gas oil condensate, heavy non-straight-run hydrocarbon feedstocks from refining, waxy residues, atmospheric residue, residue mixtures, crude oil, and any combination thereof.

[0049] The pitch compositions for spinning disclosed herein comprise pitch having a softening point temperature (T0.05) of 400°C or lower. sp ) and has a higher temperature ratio than T at a temperature change rate of 10℃ / min spAn oxidation initiation temperature (OOT) at least 10°C lower than the standard OOT. Asphalt can have a mesophase content of 0 to 100% by volume based on the total volume of asphalt; and an oxidation initiation temperature (T) of 50°C to 450°C. sp It has a glass transition temperature (T0) ranging from 20°C to 350°C. g ); having an OOT of 50°C to 400°C; having a carbon residue content of 20% to 99% by weight based on the total weight of bitumen; and / or the maximum critical stress of bitumen at the spinning temperature and in the range of 0 to 100 s. -1 It can withstand tensile strain rates ranging from 100 Pa to 10,000,000 Pa.

[0050] The term “glass transition temperature” (T) used in this article g T represents the temperature or temperature range at which a material (e.g., a polymer matrix) changes from a rigid, glassy state to a softer state. g Changes in heat capacity can be determined using differential scanning calorimetry (DSC). g This represents the midpoint of the temperature at which the heat capacity changes during the second heating scan in a DSC experiment with a heating and cooling rate of 10 °C / min. In this invention, T... g For example, thermal analysis tools such as TA Instruments Discovery DSC or TA Instruments Q2000 can be used. TM Measurement.

[0051] Asphalt can be classified as isotropic asphalt or mesophase asphalt. Generally, isotropic asphalt is converted into mesophase asphalt. The term "mesophase" as used herein refers to a polydisperse liquid crystal material (e.g., a disk-shaped liquid crystal) composed of planar aromatic molecules. "Mesophase asphalt" consists of an "intermediate phase" and optionally an isotropic phase. When examined under a polarizing microscope, the mesophase exhibits optical anisotropy. For example, mesophase asphalt can be asphalt containing more than about 10% by volume of the mesophase based on the total volume of asphalt. The mesophase content of asphalt can be detected, for example, by embedding various asphalt samples in an epoxide and then polishing the samples until they become highly reflective. A series of images can be recorded to quantify the anisotropy content, wherein the mesophase asphalt has a non-uniform two-phase structure comprising anisotropic and isotropic regions. Those skilled in the art will know that asphalt can also be called tar, bituminous asphalt, or ash, and when asphalt is produced from plants, it is also called resin. Various types of bitumen can be obtained as a product in the gas oil or naphtha cracking industry. As a carbonaceous residue, it consists of a complex mixture of major aromatic organic compounds that are solid at room temperature and exhibits a wide range of softening temperatures. Therefore, bitumen can be obtained from the heat treatment and distillation of petroleum fractions.

[0052] In at least one embodiment, the asphalt has an intermediate phase content of 0% to 100% by volume based on the total volume of asphalt (e.g., 5% or less, or 4% or less, or 3% or less, or 2% or less, or 1% or less, or 0.5% or less; or 5% or more, or 10% or more, or 20% or more, or 30% or more, or 40% or more, or 50% or more, or 60% or more, or 70% or more, or 80% or more, or 90% or more).

[0053] In at least one embodiment, the asphalt has a T value of 50°C to 450°C. sp (or 55°C to 425°C, or 60°C to 400°C, or 65°C to 375°C, or 70°C to 325°C, or 75°C to 300°C, or 80°C to 275°C, or 85°C to 250°C, or 90°C to 225°C, or 95°C to 200°C; or 50°C to 400°C, or 50°C to 300°C, or 50°C to 200°C, or 50°C to 100°C; or 100°C to 450°C, or 200°C to 450°C, or 300°C to 450°C).

[0054] In at least one embodiment, the bitumen has a glass transition temperature (T0) of 20°C to 350°C. g For example, T g It can be 30℃ to 275℃, or 50℃ to 250℃, or 60℃ to 250℃, or 100℃ to 260℃, or 125℃ to 260℃, or 150℃ to 260℃, or 175℃ to 260℃, or 200℃ to 260℃.

[0055] In at least one embodiment, the asphalt has a carbon residue content of 20% to 99% by weight, for example, 30% to 99% by weight, for example, 40% to 99% by weight, for example, 50% to 99% by weight, for example, 50% to 95% by weight, for example, 50% to 85% by weight, and for example, 50% to 80% by weight, based on the total weight of the asphalt composition.

[0056] In at least one embodiment, in terms of rheology and spinning, the pitch is stretched in the range of 0 to 100 s. -1 It has a maximum critical stress of 100 Pa to 10,000,000 Pa (e.g., 2,500 Pa to 250,000 Pa) under tensile strain.

[0057] Based on the total volume of the asphalt composition, the asphalt filler may be present in the asphalt composition in an amount of 0.01 vol% to 99 vol%, or 0.1 vol% to 99 vol%, or 1 vol% to 90 vol%, or 2 vol% to 80 vol%, or 3 vol% to 70 vol%, or 4 vol% to 60 vol%, or 5 vol% to 50 vol%, or 6 vol% to 40 vol%. Examples of asphalt fillers include, but are not limited to: carbon black, carbon nanotubes, polymers, inorganic materials (e.g., iron oxide and chromium oxide), organometallic materials, or any combination thereof. The asphalt filler may be used to provide reinforcing strength to the asphalt to be spun, or may be used to increase the total volume of the asphalt, or to improve the reactivity of the asphalt during stabilization, or to improve the stabilized fibers during carbonization, or to improve the carbonized fibers during graphitization.

[0058] The pitch compositions disclosed herein may contain pitch having a volatile content of 1 wt% or less based on the total weight of the pitch at the spinning temperature (or 0.9 wt% or less, or 0.8 wt% or less, or 0.7 wt% or less, or 0.6 wt% or less, or 0.5 wt% or less, or 0.4 wt% or less, or 0.3 wt% or less, or 0.2 wt% or less, or 0.1 wt% or less). As used herein, the term "volatile" refers to a substance that is evaporable at the corresponding temperature and may include light products obtained during a cracking reaction. The term volatile can be applied to both liquids and solids. For example, certain solid materials can be converted directly from solid to vapor without becoming liquid via a so-called sublimation process.

[0059] The bitumen compositions disclosed herein may contain bitumen having a hydrogen content of 3% to 10% by weight based on the total weight of bitumen (or 3% to 9% by weight, or 3% to 8% by weight, or 3% to 7% by weight, or 3% to 6% by weight, or 3% to 5% by weight, or 3% to 4% by weight, or 4% to 6% by weight).

[0060] The bitumen compositions disclosed herein may comprise bitumen having a nitrogen content of 0% to 3% by weight based on the total weight of bitumen (or 0% to 2% by weight, or 0% to 1% by weight, or 0.1% to 2% by weight, or 0.1% to 1.9% by weight, or 0.1% to 1.8% by weight).

[0061] The bitumen compositions disclosed herein may contain bitumen having a sulfur content of 0% to 10% by weight based on the total weight of bitumen (or 0% to 9% by weight, or 0% to 8% by weight, or 0% to 7% by weight, or 0% to 6% by weight, or 0% to 5% by weight, or 0% to 4% by weight, or 0% to 3% by weight, or 0% to 2% by weight, or 0% to 1% by weight, or 0.1% to 7% by weight).

[0062] The term "heat flow" as used in this article refers to the amount of heat transferred per unit mass of a material, typically measured as watts per gram. Heat flow is generally determined using DSC thermal analysis. DSC detects the flow of heat toward or from the sample under controlled heating conditions. A small sample (e.g., 1-10 mg) is placed in a closed crucible within a temperature-controlled furnace. A second crucible serves as a reference. The sample is then heated using a temperature-controlled furnace. The most common temperature control method is dynamic (or scanning) mode, which employs a constant heating rate. Another operating mode is isothermal mode, used to maintain a constant temperature. In both modes, the flow of heat toward or from the sample under controlled heating conditions is detected over time and temperature.

[0063] Differential scanning calorimetry (DSC) is used to determine the glass transition temperature (T) of bitumen according to ASTM D3418-03. g Using TA Instruments Discovery model Q2000 TM Obtain DSC data. A sample weighing approximately 5-10 mg can be retained in an aluminum sample pan and heat-sealed to determine the glass transition temperature T. g Alternatively, OOT detection can be performed with the sample exposed to the open. The sample is heated to 200°C at a rate of 10°C / min and held at 200°C for 5 minutes. The sample is then cooled to -90°C at a rate of 10°C / min and held at -90°C for 5 minutes. A second heating cycle is then performed by heating back to 200°C at a rate of 10°C / min. T is measured from the second heating cycle. g .

[0064] Regarding the OOT (Out of Heat) of asphalt, since the asphalt undergoes an exothermic reaction with air, the initiation of oxidation can manifest as a sudden exothermic reaction at a specific temperature. Therefore, for a specific asphalt and at a specific heating rate (e.g., 10°C / min), the exothermic reaction with air can be initiated at a specific temperature, indicating the start of oxidation. In at least one embodiment, the asphalt has an OOT of 50°C to 400°C (e.g., 75°C to 390°C, or 100°C to 380°C, or 125°C to 370°C, or 150°C to 360°C, or 160°C to 350°C, or 170°C to 340°C, or 110°C to 390°C, or 120°C to 380°C, or 130°C to 370°C, or 140°C to 360°C, or 150°C to 350°C). During the stabilization process, it is desirable to maintain the temperature OOT for a period of time.

[0065] In some cases, the bitumen compositions described herein may contain bitumen with a second OOT, for example, the second OOT may be 200°C to 400°C (or 210°C to 390°C, or 220°C to 380°C, or 330°C to 370°C). Without being limited by any theory, the second exothermic reaction may originate from the reaction between air and different components within the bitumen. For example, mesophase bitumen may simultaneously have anisotropic and isotropic phases, and the first OOT may correspond to one component in the bitumen, while the second OOT may correspond to a second component in the bitumen; similarly, bitumen may have different amounts of reactive groups, and different OOT temperatures may reflect these reactive groups (e.g., olefins, benzyl hydrogen, etc.). Alternatively, it may reflect the OOT of a second bitumen contained in a spinning bitumen blend.

[0066] In some cases, it can be beneficial to enhance the reactivity of asphalt by adding additives, which can act as catalysts for stabilization, carbonization, or graphitization processes. Alternatively, these additives can act as stoichiometric reactants with the asphalt itself. Representative types of catalysts include organometallic and inorganic complexes, with typical metals selected from the following group: sodium, potassium, calcium, iron, nickel, tungsten, cobalt, lithium, magnesium, titanium, vanadium, chromium, copper, zinc, zirconium, molybdenum, or aluminum.

[0067] Methods for producing carbon fiber

[0068] In at least one embodiment, the asphalt or asphalt mixture has a softening point below 400°C (T0.05). sp ) and having in T sp -30℃ and T spSpinning temperatures between +80°C and 80°C. The bitumen can have a mesophase content of 5 vol% or less based on the total bitumen volume. Alternatively, the bitumen can have a mesophase content of 5 vol% to 100 vol% based on the total bitumen volume. Furthermore, the bitumen can be spun from 0 to 100 s. -1 It exhibits tensile viscosities ranging from 5 Pa·s to 500,000 Pa·s at tensile strain rates. Asphalt can be dissolved in air at TT... sp It has an apparent rate constant (k) for oxidation at ≤0℃. app Greater than 0.001s -1 (e.g. TT) sp Within the range of -500℃ to 0℃, for example, TT sp Within the range of -450℃ to 0℃, for example, TT sp Within the range of -400℃ to 0℃, for example, TT sp Within the range of -350℃ to 0℃, for example, TT s Within the range of -300℃ to 0℃, for example, TT sp Within the range of -250℃ to 0℃, for example, TT sp (Within the range of -200℃ to 0℃).

[0069] The method disclosed herein may also include spinning bitumen at a temperature of 50°C to 430°C (or 75°C to 420°C, or 100°C to 410°C, or 125°C to 400°C, or 150°C to 390°C, or 175°C to 380°C) at a spinning speed of 1 m / min to 3,000 m / min (or 20 m / min to 2,000 m / min, or 50 m / min to 1,500 m / min, or 100 m / min to 1,000 m / min, or 200 m / min to 900 m / min, or 300 m / min to 800 m / min, or 400 m / min to 700 m / min, or 500 m / min to 600 m / min).

[0070] The spinning process can use capillary size r0 and final fiber radius r f The spinneret is used for spinning, where the ratio r f / r0=exp(-ε R / 2), where r f Within the range of 1 μm to 1,000 μm, r0 is within the range of 100 μm to 10,000 μm, and the maximum Hencky strain within the spinning temperature range is at least In at least one embodiment, at spinning temperatures ranging from 30°C lower than the softening point of the bitumen composition to 80°C higher than the softening point of the bitumen composition, the capillary size r0 is r f / [exp(-ε R / 2)], where ε R It is 0.7 or greater. The capillary size r0 can range from 50 μm to 5,000 μm, or 75 μm to 4,000 μm, or 100 μm to 3,000 μm, or 150 μm to 1,500 μm, or 200 μm to 1,000 μm. For example, the capillary size r0 can be 300 μm.

[0071] The spinning process can be melt spinning. This process can use a pitch composition having a softening point of 100°C to 400°C (or greater than 110°C, or greater than 120°C, or greater than 130°C, or greater than 140°C, or greater than 150°C, or greater than 160°C, or greater than 170°C, or greater than 180°C, or greater than 190°C, or greater than 200°C, or greater than 210°C, or greater than 220°C, or greater than 230°C, or greater than 240°C, or greater than 250°C, or greater than 260°C, or greater than 270°C, or greater than 280°C, or greater than 290°C, or greater than 300°C, or greater than 310°C, or greater than 320°C, or greater than 330°C, or greater than 340°C, or greater than 350°C). The pitch composition described herein can be added to an extruder, where it can be heated, sheared, and extruded via capillary to form carbon fibers.

[0072] In at least one embodiment, the method herein includes spinning carbon fibers, wherein the pitch has a temperature greater than 10°C (T). sp -OOT), and the selection of the spinning temperature therein such that the volatile content (wt%) based on the total weight of the pitch is less than 1 wt%, for example less than 0.8 wt%, for example less than 0.6 wt%, for example less than 0.4 wt%, as determined by TGA. Thermogravimetric analysis (TGA) is used to determine the amount and rate of change of a sample mass with temperature and time in a controlled atmosphere. TGA techniques can be used to characterize those materials whose mass decreases or increases due to volatilization loss, decomposition, and oxidation. TGA assays provide valuable information that can be used for material selection, confirming reactivity, quantifying composition and / or impurity levels, polymer characterization, moisture content, and volatile content. The ASTM E2550 standard test method for determining thermal stability by thermogravimetric analysis involves determining the temperature at which a material begins to decompose or react and the extent of mass change by thermogravimetric analysis, thereby assessing the material's thermal stability.

[0073] For example, the method disclosed herein may also include: blending two or more pitches and extruding the blended pitches as a mixture. In another example, the method disclosed herein may also include: co-extruding two or more pitches using a method that mechanically results in a core-shell filament structure, thereby employing different pitches in the core and shell. In this case, the rheology of the pitches should be carefully designed so that one pitch flows preferentially around the others. In some cases, it may be desirable for the first and second pitches to have different viscosities. Blending two or more pitches can help control melt spinning or help control the properties of the corresponding carbon fibers formed from the pitches (e.g., tensile strength, reactivity with oxygen, etc.).

[0074] For example, the methods disclosed herein may include blending a first bitumen with one or more bitumens, wherein the blending operation enables the design of the bitumen composition to have spinnability or fiber properties, or reactivity, or any combination of these properties.

[0075] In some cases, two or more types of pitch can be used to form fibers without the need for complete blending. For example, in the production of core-shell filaments, a first pitch can form a first carbon fiber as a first layer (e.g., an inner / core layer), and a second pitch can form a second carbon fiber as a second layer (e.g., an outer layer) on the surface of the first layer. Other non-limiting examples of core-shell filaments may include: 1) having a second pitch formed on the surface of the first pitch, wherein the second pitch has a greater reaction rate with air than the first pitch to obtain an oxide layer, thereby preventing the fibers from becoming sticky during winding; 2) the pitch on the outer side has higher stiffness than the pitch on the inner side; 3) the pitch on the outer side is more tolerant of surface defects than the pitch on the inner side; 4) the second pitch is primarily used to prepare significantly narrower fibers in the core / inner layer, thereby increasing the strength of the core / inner fiber layer; 5) the second pitch forms a better interface with the matrix. When core-shell fibers are required, the rheological behavior of the pitches should be carefully designed so that one pitch preferentially flows around the other pitches.

[0076] The method described herein may further include: heating bitumen, fibers or fiber webs derived from bitumen at a temperature of 50°C or higher (or 75°C or higher, or 100°C or higher, or 150°C or higher, or 200°C or higher, or 250°C or higher, or 300°C or higher, or 350°C or higher, or 400°C or higher, or 450°C or higher, or 500°C or higher) in the presence of air at a heating rate of 0.5°C / min or higher (or 1°C / min or higher, or 3°C / min or higher, or 5°C / min or higher, or 7°C / min or higher, or 10°C / min or higher, or 15°C / min or higher, or 20°C / min, or 30°C / min, or 40°C / min, or 50°C / min). Oxidation can be performed at rates of 60°C / min, 70°C / min, 80°C / min, 90°C / min, 100°C / min, 150°C / min, 200°C / min, or greater, for periods ranging from 0.1 seconds to 48 hours (e.g., 0.1 seconds to 36 hours, 0.1 seconds to 24 hours, 0.1 seconds to 12 hours, 0.1 seconds to 6 hours, 0.1 seconds to 5 hours, 0.1 seconds to 4 hours, 0.1 seconds to 3 hours, 0.1 seconds to 2 hours, 0.1 seconds to 1 hour, 0.1 seconds to 50 minutes, 0.1 seconds to 40 minutes, 0.1 seconds to 30 minutes, 0.1 seconds to 20 minutes, 0.1 seconds to 10 minutes, or 0.1 seconds to 5 minutes). Alternatively, stabilization can be achieved by continuously passing the fibers or fiber web through the oven, wherein the residence time and temperature are within the aforementioned ranges. Additional reactive gases may be used, such as ozone, oxygen, nitrogen / oxygen blends, nitrogen oxides, hydrogen peroxide, or any combination thereof.

[0077] Oxidation can begin due to an exothermic reaction between asphalt and oxygen in the air, and can be observed through a sudden exothermic reaction at the stated temperature. In some cases, asphalt oxidation can begin at an OOT of 350°C or lower (or 340°C or lower, or 330°C or lower, or 320°C or lower, or 310°C or lower, or 300°C or lower, or 290°C or lower, or 280°C or lower, or 270°C or lower, or 260°C or lower, or 250°C or lower, or 240°C or lower, or 230°C or lower, or 220°C or lower, or 210°C or lower, or 200°C or lower, or 190°C or lower, 180°C or lower, 170°C or lower, or 160°C or lower). In some other cases, asphalt can exhibit two oxidation initiations, where the second exothermic reaction (e.g., a second OOT) can be greater than the first OOT. The second OOT can be above 200°C (or 225°C or higher, or 250°C or higher, or 275°C or higher, or 300°C or higher, or 325°C or higher, or 350°C or higher). Without being limited to any theory, the second OOT can originate from the reaction between asphalt with a sufficient amount of reactive mesophase and oxygen in the air, or the asphalt can have varying amounts of reactive groups, and different OOT temperatures can reflect the softening of these reactive groups (e.g., olefins, benzyl hydrogen, etc.) or the mesophase.

[0078] Once the fibers or fiber mats have been spun, they undergo oxidation, carbonization, and / or graphitization, transforming the fibers (often referred to as nascent fibers) into stable fibers, carbon fibers, and / or graphite fibers, or oxidized fiber webs, carbonized fiber webs, or graphitized fiber webs. The bitumen compositions described herein can be used to produce binder bitumen, graphitizable carbon microspheres, solid lubricants, activated carbon fibers, battery anodes, and carbon foams.

[0079] Various methods have been proposed in the prior art for stabilizing pitch-based carbon fibers, the most common being oxidation treatment in an oxygen-containing atmosphere, such as air. The stabilization of pitch fibers is a solid-phase oxidation reaction, thereby converting the pitch into a non-meltable form. In some cases, the air may contain NO2 as an oxidizing gas. The stabilizing effect improves the strength of the carbon fibers and makes them non-meltable. Oxidation of the fiber surface layer is generally faster than that of the fiber center, so the resulting stabilized fibers exhibit different degrees of oxidation at the surface and center. The oxidation at the surface and center can be optimally controlled, for example, by adding water to the oxidizing atmosphere, such as air.

[0080] The stabilized bitumen can then be carbonized by heating in an inert or mostly inert atmosphere to a temperature ranging from 500°C to 2000°C. If graphitization is required, the carbonized fibers can then be graphitized by additional heating in an inert or mostly inert atmosphere to a temperature ranging from 1600°C to 3000°C.

[0081] Methods for producing carbon fiber composites

[0082] The methods disclosed herein may also include combining a matrix material with spun fibers to form a carbon fiber composite material. Based on the total volume of the carbon fiber composite material, the carbon fiber composite material may have a carbon fiber content of 1 vol% to 70 vol% (or 2.5 vol% to 60 vol%, or 5 vol% to 50 vol%, or 10 vol% to 40 vol%), and / or a matrix content of 30 vol% to 99 vol% (or 40 vol% to 97.5 vol%, or 50 vol% to 95 vol%, or 60 vol% to 90 vol%). Alternatively, bitumen may also be used as a binder / matrix for composite material applications, such as for the production of carbon / carbon composite materials. When bitumen is used as a binder / matrix, the filler in the composite material may be carbon fiber, glass fiber, metal fiber, boron fiber, carbon black, carbon nanotubes, and combinations thereof. For example, bitumen itself may be used as a matrix and / or binder in the production of carbon-carbon composite materials.

[0083] The matrix materials used herein can be prepared from the following materials: thermosetting polymers (e.g., cyclopentadiene, dimercyclopentadiene, epoxides, bitumen, phenolic resins, vinyl esters, polyimides, and polyesters), thermoplastic polymers (e.g., including one or more of the following thermoplastic polymers: polyethylene, polypropylene, high-density polyethylene, linear low-density polyethylene, low-density polyethylene, polyamide, polyvinyl chloride, polyetheretherketone, polyetherketoneketone, polyaryletherketone, polyetherimide, and polyphenylene sulfide), cement, concrete, ceramics, metals, metal alloys, or combinations thereof.

[0084] The most widely used polymer matrix in commercial and high-performance aerospace applications for composite materials is thermosetting resin, also known as a "thermosetting polymer matrix," which consists of polymer chains that permanently cure into a cross-linked network when mixed with a catalyst, exposed to heat, or both. Thermosetting matrices can include cement, concrete, ceramics, peels, metals, or metal alloys. Thermosetting matrices can be incorporated into resins, such as polyesters, vinyl esters, epoxy resins, bismaleimides, cyanate esters, polyimides, or phenolic plastics. When cured by heat and / or chemicals (catalysts or accelerators) or other methods, the thermosetting matrix becomes substantially inmeltable and insoluble. After curing, the thermosetting matrix cannot return to its uncured state. Curing is typically carried out under elevated temperature and / or pressure conditions in an oven and / or vacuum bag or in an autoclave. Alternative, but less commonly used, techniques include electron beam, ultraviolet (UV) irradiation, X-ray, and microwave methods. When cured, the thermosetting polymer matrix becomes substantially inmeltable and insoluble. Once cured, the thermosetting polymer matrix cannot return to its uncured state. Composites made from thermosetting matrices are strong and have very good fatigue strength. However, such composites can be extremely brittle and may have low impact toughness. Because the thermosetting polymer matrix does not melt, it is often used in high-temperature and / or chemical-resistant applications.

[0085] Other commonly used matrix types are thermoplastic (TP) resins, also known as "thermoplastic polymer matrices" or simply "thermoplastic matrices," which are increasingly becoming the preferred choice for composite material manufacturers. TP polymers are those polymers that can be molded, melted, and remolded without altering their chemical structure. In some cases, thermoplastic matrices can exhibit better rigidity and lower brittleness than thermoset matrices, providing excellent impact resistance and damage resistance. In other cases, thermoplastic matrices can become glassy and very brittle at temperatures lower than their glass transition temperature. Because the matrix can be melted, composites are easier to repair and can be readily remolded and recycled. Thermoplastic matrices can be more porous than thermoset matrices, making them a valuable option for weight-critical applications. For the purposes of this invention, the thermoplastic polymer may be selected from the group consisting of: polyethylene, polypropylene, high-density polyethylene, linear low-density polyethylene, low-density polyethylene, polyamide, polyvinyl chloride, polyetheretherketone, polyetherketoneketone, polyaryletherketone, polyetherimide, and polyphenylene sulfide, and any combination thereof.

[0086] The matrix used herein can be prepared from the following materials: thermosetting polymers (e.g., cyclopentadiene, dimercyclopentadiene, epoxides, phenolic resins, vinyl esters, polyimides, and polyesters), thermoplastic polymers (e.g., including one or more of the following thermoplastic polymers: polyethylene, polypropylene, high-density polyethylene, linear low-density polyethylene, low-density polyethylene, polyamide, polyvinyl chloride, polyetheretherketone, polyetherketoneketone, polyaryletherketone, polyetherimide, and polyphenylene sulfide), cement, concrete, ceramics, metals, metal alloys, or combinations thereof.

[0087] The carbon fiber composite material disclosed herein may comprise: a matrix material and carbon fibers derived from a pitch composition, wherein the pitch composition comprises pitch having a softening point temperature of 400°C or lower (T0). sp ) and has a higher temperature ratio than T at a temperature change rate of 10℃ / min sp Oxidation onset temperature (OOT) at least 10°C lower.

[0088] For the purposes of this invention, the thermoplastic polymer is selected from the group consisting of polyethylene, polypropylene, high-density polyethylene, linear low-density polyethylene, low-density polyethylene, polyamide, polyvinyl chloride, polyetheretherketone, polyetherketoneketone, polyaryletherketone, polyetherimide, and polyphenylene sulfide, and any combination thereof.

[0089] In addition, the carbon fibers disclosed herein can be used in textile materials (e.g., for weaving wide-width products). These materials can be used to produce, for example, tapes and prepregs. Furthermore, pitch can be used to produce continuous filaments wound onto spools and to produce nonwoven fabrics, such as meltblown or spunbond fabrics, in which fibers are laid out as a web or mat.

[0090] Non-limiting examples of carbon products may include automotive body parts (e.g., trunk lids, hoods, front ends, bumpers, doors, chassis, suspension systems such as leaf springs, drive shafts), offshore tethers and drilling risers, wind turbine blades, insulation and sealing materials (e.g., cement) used in structural and road construction, aerospace and aviation systems, high-performance underwater containers, aircraft, sports equipment, unmanned aerial vehicles, armor, armored vehicles, military aircraft, energy storage systems, fire-resistant materials, lightweight cylinders and pressure vessels, and medical devices. Additionally, the fibers disclosed herein (e.g., fiber filaments or webs) can be used as insulation materials (e.g., thermal or sound insulation), or as shielding materials (e.g., electromagnetic or radio frequencies), or in friction control surfaces (e.g., brake pads, such as aircraft brake pads). Carbon fibers may be incorporated together with graphite foam, and pitch compositions having the aforementioned properties can be used to produce graphite foam for explosion protection, etc.

[0091] The implementation plan disclosed in this article includes:

[0092] A. A pitch composition suitable for spinning. This pitch composition comprises pitch having a softening point temperature (T0.05) of 400°C or lower. sp ) and has a higher temperature ratio than T at a temperature change rate of 10℃ / min sp Oxidation onset temperature (OOT) at least 10°C lower.

[0093] B. Carbon fiber. This carbon fiber comprises: carbon fiber obtained from a pitch composition, wherein the pitch composition contains pitch having a softening point temperature of 400°C or lower (T0). sp ) and has a higher temperature ratio than T at a temperature change rate of 10℃ / min sp Oxidation onset temperature (OOT) at least 10°C lower.

[0094] C. Carbon fiber composite material. This carbon fiber composite material comprises: a matrix material; and carbon fibers obtained from a pitch composition, wherein the pitch composition contains pitch having a softening point temperature of 400°C or lower (T0). sp ) and has a higher temperature ratio than T at a temperature change rate of 10℃ / min sp Oxidation onset temperature (OOT) at least 10°C lower.

[0095] D. A method for stabilizing carbon fibers. The method includes: providing bitumen having a softening point temperature (T0.05) of 400°C or lower. sp ) and T sp The oxidation initiation temperature (OOT) is at least 10°C lower than that of the pitch; the pitch is spun to prepare carbon fibers; and the carbon fibers are stabilized in the presence of air or other reactive gases, thereby by heating the carbon fibers to a temperature lower than that of the pitch. sp Stable carbon fibers are obtained at temperatures at least 10°C lower.

[0096] E. A method for preparing a pitch composition suitable for spinning. The method comprises: introducing a hydrocarbon feed into one or more reaction zones to produce a reaction effluent, wherein the reaction effluent is fed into one or more separation zones to classify the reaction effluent, thereby obtaining a pitch product, wherein the pitch product has a Tg ratio greater than that of the hydrocarbon feed. sp Higher T sp and has a higher T than asphalt products at a temperature change rate of 10℃ / min. sp OOT at least 10°C lower.

[0097] Implementation schemes A, B, C, D, and E may have one or more of the following elements in any combination:

[0098] Element 1: The bitumen contains an intermediate phase content of 0% to 100% by volume based on the total volume of bitumen.

[0099] Element 2: The bitumen contains 5% or less of the mesophase content based on the total volume of bitumen.

[0100] Element 3: The asphalt contains more than 5% by volume of mesophase based on the total volume of asphalt.

[0101] Element 4: The bitumen has a volatile content of 1% by weight or less based on the total weight of bitumen at the spinning temperature.

[0102] Element 5: The asphalt has a temperature of 50°C or higher. sp .

[0103] Element 6: The asphalt has a temperature range of 80℃ to 400℃. sp .

[0104] Element 7: The bitumen has a glass transition temperature (T0) ranging from 20°C to 350°C. g ).

[0105] Element 8: Wherein the asphalt has a carbon residue content of 20% to 99% by weight based on the total weight of the asphalt.

[0106] Element 9: Where OOT is in the range of 100℃ to 400℃.

[0107] Element 10: Where asphalt has a second OOT.

[0108] Element 11: The second OOT is in the range of 200°C to 400°C.

[0109] Element 12: Wherein the pitch is at the spinning temperature and / or between 0 and 100 s -1 It has a maximum critical stress of 100 Pa to 10,000,000 Pa at tensile strain rates.

[0110] Element 13: wherein at the spinning temperature and / or in the range of 0 to 100 s -1 At a tensile strain rate, the maximum critical stress is in the range of 2,500 Pa to 250,000 Pa.

[0111] Element 14: Where the pitch is at the spinning temperature and / or between 0 and 100 s -1 It has tensile viscosities ranging from 5 Pa·s to 500,000 Pa·s at tensile strain rates.

[0112] Element 15: Among them, asphalt in TT sp It has an apparent rate constant (k) for oxidation in air at ≤0℃. app Greater than 0.001s -1 .

[0113] Element 16: The bitumen composition is a blend of two or more types of bitumen.

[0114] Element 17: Fibers, oxidized fibers, carbonized fibers, graphitized fibers, fiber webs, oxidized fiber webs, carbonized fiber webs or graphitized fiber webs prepared using the bitumen composition of any one of the preceding elements.

[0115] Element 18: Adhesive bitumen, graphitizable carbon microspheres, solid lubricant, activated carbon fiber, battery anode and carbon foam prepared from the bitumen composition of any one of the preceding elements.

[0116] Element 19: The carbon fibers produced are stabilized in the presence of air.

[0117] Element 20: Carbon fibers are prepared from a pitch composition, wherein the pitch composition comprises pitch having a softening point temperature of 400°C or lower. sp ) and has a higher temperature ratio than T at a temperature change rate of 10℃ / min sp Oxidation onset temperature (OOT) at least 10°C lower.

[0118] Element 21: Wherein the bitumen contains an intermediate phase content of 0% to 100% by volume based on the total volume of bitumen.

[0119] Element 22: Wherein the bitumen has a volatile content of 1% by weight or less based on the total weight of bitumen at the spinning temperature.

[0120] Element 23: Among them, asphalt has a temperature greater than 10℃ (T) sp -OOT1), and wherein the carbon fibers are spun at a spinning temperature, the spinning temperature being chosen such that the volatile content is less than 1% by weight based on the total weight of the pitch.

[0121] Element 24: Where the asphalt has a temperature of 50°C or higher. sp .

[0122] Element 25: Where the asphalt has a T temperature of 80°C to 400°C sp .

[0123] Element 26: The bitumen has a glass transition temperature (T0) ranging from 20°C to 350°C. g ).

[0124] Element 27: Wherein the bitumen has a carbon residue content of 20% to 99% by weight based on the total weight of bitumen.

[0125] Element 28: Where OOT is in the range of 100°C to 400°C.

[0126] Element 29: Where the asphalt has a second OOT of 200°C to 400°C.

[0127] Element 30: where asphalt is within 0 to 100 seconds -1 It has a maximum critical stress of 100 Pa to 10,000,000 Pa at tensile strain rates.

[0128] Element 31: Where asphalt is within 0 to 100 seconds -1 It has tensile viscosities ranging from 5 Pa·s to 500,000 Pa·s at tensile strain rates.

[0129] Element 32: Among them, asphalt in TT sp It has an apparent rate constant (k) for oxidation in air at ≤0℃. app Greater than 0.001s -1 .

[0130] Element 33: The fiber is produced by spinning two or more types of pitch together.

[0131] Element 34: The bitumen composition is a blend of two or more types of bitumen.

[0132] Element 35: Where the bitumen contains 5% or less of an intermediate phase based on the total volume of bitumen.

[0133] Element 36: Wherein the bitumen contains more than 5% by volume of mesophase based on the total volume of bitumen.

[0134] Element 37: wherein the bitumen has a volatile content of 1% by weight or less based on the total weight of bitumen at the spinning temperature.

[0135] Element 38: Among them, asphalt has a temperature change rate of 10℃ / min and a temperature (T) greater than 10℃. sp -OOT1), and wherein the carbon fibers are spun at a spinning temperature, the spinning temperature being chosen such that the volatile content is less than 1% by weight based on the total weight of the pitch.

[0136] Element 39: Where the asphalt has a temperature of 50°C or higher. sp .

[0137] Element 40: Where the asphalt has a T value of 80℃ to 400℃ sp .

[0138] Element 41: Where OOT is in the range of 100℃ to 400℃.

[0139] Element 42: Where the asphalt has a second OOT of 200°C to 400°C.

[0140] Element 43: The bitumen composition is a blend of two or more types of bitumen.

[0141] Element 44: Wherein the bitumen composition in TT sp It has an apparent rate constant (k) for oxidation in air at ≤0℃. app Greater than 0.001s -1 .

[0142] Element 45: The fiber is produced by spinning two or more pitches together.

[0143] Element 46: The matrix is ​​a thermosetting matrix, a thermoplastic matrix, cement, concrete, ceramics, metal, metal alloy, asphalt, or a combination thereof.

[0144] Element 47: wherein the thermoplastic matrix is ​​selected from the group consisting of polyethylene, polypropylene, high-density polyethylene, linear low-density polyethylene, low-density polyethylene, polyamide, polyvinyl chloride, polyetheretherketone, polyetherketoneketone, polyaryletherketone, polyetherimide and polyphenylene sulfide, and any combination thereof.

[0145] Element 48: Wherein, based on the total volume of carbon fiber composites, the carbon fiber content is 1 vol% to 70 vol%, and the matrix content is 30 vol% to 99 vol%.

[0146] Element 49: Wherein the asphalt has an intermediate phase content of 5% or less based on the total volume of asphalt.

[0147] Element 50: wherein the bitumen has an intermediate phase content of 5% to 100% by volume based on the total volume of bitumen.

[0148] Element 51: Where asphalt is within 0 to 100 seconds -1 It has tensile viscosities ranging from 5 Pa·s to 500,000 Pa·s at tensile strain rates.

[0149] Element 52: The hydrocarbon feedstock is selected from the following group: crude oil, MCB bottom oil, steam cracker tar, hydrotreated MCB, hydrotreated steam cracker tar, vacuum residue, atmospheric residue, reformate, naphthalene, coal tar, coal tar pitch, vacuum gas oil, distillate oil, or any of the above feedstocks in a hydrotreated form.

[0150] Element 53: The separation zone includes flash tanks, distillation columns, chromatographic separation, membrane filtration, or deasphalting.

[0151] Element 54: The reaction zone includes fixed-bed reactors, slurry reactors, tubular reactors, continuous stirred tank reactors, batch reactors, or semi-batch reactors.

[0152] Element 55: Among them, the T of bitumen products spWithin the range of 100℃ to 400℃.

[0153] Element 56: The bitumen product has an intermediate phase content of about 5% by volume or more based on the total volume of the bitumen product.

[0154] Element 57: The bitumen product has a mesophase content of less than 5% by volume based on the total volume of the bitumen product.

[0155] As a non-limiting example, exemplary combinations that can be used for scheme A include, but are not limited to: 1 or 2, and 3; 1 or 2, and 4; 1 or 2, and 5; 1 or 2, and 6; 1 or 2, and 7; 1 or 2, and 8; 1 or 2, and 9; 1 or 2, and 10; 1 or 2, and 10 and 11; 1 or 2, and 12; 1 or 2, and 13; 1 or 2, and 13-20; 1 or 2, and 14 and 15; 1 or 2, and 16; 1 or 2, and 15-20; 1 or 2, and 18; 1 or 2, and 19; 1 or 2, and 19 and 20; 1 or 2, and 6; 13 and 14; 13 and 15; and 13 and 16; and 18 and 19; and 19 and 20.

[0156] As a non-limiting example, exemplary combinations that can be used for scheme B include, but are not limited to: 21 or 22, and 23; 21 or 22, and 24; 21 or 22, and 25; 21 or 22, and 26; 21 or 22, and 27; 21 or 22, and 28; 21 or 22, and 29; 21 or 22, and 30; 21 or 22, and 31; 21 or 22, and 32; 21 or 22, and 33; 21 or 22, and 34; 21 or 22, and 23 and 26; 21 or 22, and 25-29; 21 or 22, and 26-34; 21 or 22, and 25; 26 and 29; and 31 and 33.

[0157] As a non-limiting example, exemplary combinations that can be used in scheme C include, but are not limited to: 35 or 36, and 37; 35 or 36, and 38; 35 or 36, and 39; 35 or 36, and 40; 35 or 36, and 41; 35 or 36, and 42; 35 or 36, and 43; 35 or 36, and 44; 35 or 36, and 45; 35 or 36, and 46; 35 or 36, and 47; 35 or 36, and 48; 35 or 36, and 38-41; 35 or 36, and 39 and 40; 35 or 36, and 42-44; 35 or 36, and 38; 40 and 41; 42 and 44; and 47 and 48.

[0158] As a non-limiting example, exemplary combinations that can be used for scheme D include, but are not limited to: 49 or 50, and 51.

[0159] As a non-limiting example, exemplary combinations that can be used for scheme E include, but are not limited to: 52 or 53, and 54; 52 or 53, and 55; 52 or 53, and 56; 52 or 53, and 57; 52 or 53, and 54-57.

[0160] To facilitate a better understanding of the embodiments disclosed herein, the following preferred or representative embodiments are provided. However, these embodiments should not be construed as limiting or restricting the scope of the invention. Example

[0161] A series of pitches were prepared from hydrotreated steam cracker tar. The resulting products were subjected to vacuum distillation to obtain a vacuum distillation bottoms fraction at +1,049°F (+565°C). This vacuum distillation bottoms fraction had the following properties: softening point 170°C, 38.6 wt% MCRT, 92.09 wt% C, 7.41 wt% H, 0.00 wt% N, and 0.51 wt% S.

[0162] Each isotropic bitumen was heat-treated at 400°C for 0, 1, 2, 3, 4, 5, or 6 hours to obtain the corresponding heat-treated bitumen (samples 1-14). Table 1 shows the properties of samples 1-14 (e.g., % yield, % MCRT (carbon residue), % C, % H, % N, % S, mesophase content).

[0163] Representative processes for obtaining heat-treated bitumen:

[0164] Approximately 2g of the vacuum distillate was placed in a tubular bottle and then placed in an MCRT160 trace carbon residue analyzer. This apparatus uses a 600cm... 3 Purge with nitrogen at a rate of [number] cm / min and heat to 100°C over 10 minutes, then heat to 400°C over 30 minutes. Immediately after reaching 400°C, reduce the flow rate to 150 cm / min. 3 The sample is held at a flow rate of 600 m / min for the specified time. Once the required soaking time is reached, heating is stopped and the nitrogen flow rate is increased to 600 cm⁻¹. 3 The device is cooled by a speed of [speed / min]. The temperature typically drops to 300°C in about 25 minutes, to 200°C in about 65 minutes, and to 120°C in about 137 minutes.

[0165] The mesophase content is determined as follows: The bitumen sample is embedded in an epoxide, and then polished until the surface becomes highly reflective. A series of images is then acquired to quantify the anisotropic content. Typically, 10 images are needed to determine the mesophase content.

[0166] The in-house glass transition temperature (T0) was measured using a TA Instruments Q2000TMDSC in an inert atmosphere. g The instrument is equipped with a liquid nitrogen accessory for cooling to sub-zero temperatures. The TA Instruments Q2000TMDSC has an operating lower limit of -170°C and an operating upper limit of 400°C.

[0167] Instrument calibration:

[0168] The DSC is calibrated over a temperature range of -170°C to 400°C, using indium metal as specified by the manufacturer as the calibration metal, with temperature and heat of fusion calibrated at a heating rate of 10°C / min. Instrument performance is evaluated within stringent limits by comparing the heat of fusion of indium to the literature value of 28.46 J / g, provided the difference is greater than 3%. If the initial temperature consistently deviates from the acceptable literature value of 156.6°C by more than 0.3°C, the instrument is recalibrated.

[0169] method :

[0170] The glass transition temperatures of samples 1-13 were determined using the following procedure in an internal DSC:

[0171] -Equilibrium at 200℃;

[0172] - Maintain temperature for 5 minutes;

[0173] -Cool down to -90°C at a rate of 10°C / min;

[0174] - Maintain temperature for 5 minutes;

[0175] - Heat to 200°C at a rate of 10°C / min (T is detected during this heating step). g ).

[0176] T was determined by calorimetry. g :

[0177] Differential scanning calorimetry (DSC) is used to determine the glass transition temperature (T0) of bitumen according to the following standard test methods. g ) and melting temperature (T) m ):

[0178] -DIN 53 765 (1994), Testing of plastics and elastomers—thermal analysis; DSC—methods / notes: EQV ISO11357-5 (1999).

[0179] -ASTM D 3418 (1999), a standard test method for determining transition temperature by differential scanning calorimetry.

[0180] -ISO 11357-1(1997), Plastics - Differential scanning calorimetry (DSC) - Part 1: General principles.

[0181] T of asphalt samples g Defined as the phase change that occurs when a sample transitions from a glassy state to a mobile state. Chain segments in T... g The above times show a ratio lower than T. g Greater activity at certain times (e.g., in a frozen state). Because in T g New forms of chain segment mobility changes occur, thus the specific heat capacity C of the asphalt sample increases. P Gradual changes also occur, which are detected by changes in total heat flux obtained from DSC, such as... Figure 1 As shown. The temperature range in which this transition occurs is also called the glass transition range or freezing range. The temperature measured at which half of the specific heat capacity change occurs is called T. g The reproducibility of the test results is + / -2℃, and the repeatability is + / -1℃. Figure 1 This is a DSC curve showing the change in heat flux (W / g) of asphalt (sample 4) in air with temperature (°C). i This represents the first measurable offset point from the extrapolated baseline before the transition. T fi This indicates the last offset point from the extrapolated baseline that exceeds the transition. T e T represents the intersection of the tangent line drawn at the point of maximum slope on the transformation curve after the transformation and the extrapolated baseline. T0 represents the intersection of the tangent line drawn at the point of maximum slope on the transformation curve before the transformation and the extrapolated baseline. mid This indicates the point on the thermal curve that corresponds to half the difference in heat flow between the extrapolation start and extrapolation end points.

[0182] Each type of bitumen is characterized by the MCRT measured according to the ASTM D4530-15 standard test method, using METTLER. Mettler The softening point T measured by DP70) sp Following a procedure similar to ASTM D3104, elemental analysis, TGA, and DSC in air or nitrogen were performed at a temperature variation rate of 2 °C / min. DSC in air was used to determine the OOT (Out of Heat) of each asphalt, and TGA was used to determine the amount of volatiles present in each asphalt. The temperature difference (T) for each asphalt was obtained from these tests. sp -OOT). The heating rate was set to 10℃ / min. Table 1 shows the softening point and oxidation initiation of a series of asphalts (e.g., samples 1-14). (T spPitches with positive -OOT values ​​(e.g., samples 3-8 and 11-14) demonstrate sufficient reactivity to allow an exothermic reaction with air at temperatures below their softening point, thus making them suitable for spinning into carbon fibers. sp Asphalt with negative -OOT values ​​(e.g., samples 1-2 and 9-10) demonstrates insufficient reactivity to allow an exothermic reaction with air at temperatures below its softening point. The results from samples 1-2 and 9-10 indicate that fibers derived from one of these asphalts will melt before the asphalt reacts with air. On the other hand, asphalt with negative -OOT values... sp A positive value for -OOT indicates that the asphalt can react at temperatures below its softening point. sp It is the softening point of asphalt. (T) g It is the glass transition temperature, corresponding to the phase change of the material from the glassy state to the active state, which is reflected by the change in specific heat capacity. g The inflection point also represents T as defined above. i T g The endpoint also represents T. fi ΔT g (°C) is measured using T g Endpoint (°C) minus T g The difference obtained from the starting point (°C) reflects the molecular weight distribution of the asphalt sample, where T... g The width of the transition is an indicator of the breadth of molecular structure / dispersion. OOT1 is the oxidation onset temperature recorded during the first exothermic process. In some cases, a second exothermic event occurs, so the second oxidation onset temperature is recorded and denoted as OOT2.

[0183] Table 1

[0184]

[0185] Table 1 (continued)

[0186]

[0187] Table 1 (continued)

[0188]

[0189] The oxidation kinetics of asphalt samples were determined by an OOT (Occurrence-Over-Oxidation) study with a variable rate of change (see Table 2). Figure 2A and Figure 2B ). Figure 2A The oxidation kinetics of hydrotreated steam cracker tar (HDT SCT) and vacuum residue formed from mesophase pitch from said HDT SCT are depicted, expressed as the natural logarithm of the apparent rate ln(rate of change) relative to (1 / OOT), where OOT corresponds to the oxidation initiation temperature. Figure 2BIt describes the apparent rate constant (k) predicted based on the activation parameters determined from kinetic analysis. obs ,s -1 At the asphalt softening point T sp The graphs at different temperatures are used as the difference (T). 实际 –T sp The variable rate of change study revealed the activation parameters for each asphalt sample, obtained by plotting the natural logarithm (log) of the rate of change relative to the OOT plot. The apparent rate constant (k) of stabilization was calculated from these activation parameters. app ), and used the predicted apparent rate constant (k app ) relative to (1 / OOT) plotting, such as Figure 2A As shown. Predicted apparent rate constants (k) at different temperatures. app Then, relative to the softening point temperature T sp Correlation of temperature difference values, plotting the apparent rate constant (k app The curve showing how the absolute temperature of the asphalt sample changes with the temperature difference between its softening point and the absolute temperature of the asphalt sample allows us to understand the relationship between the asphalt sample and its temperature (T). sp Related performance ( Figure 2B “A” is the pre-exponential factor (s) -1 E a It is the activation energy (kJ / mol).

[0190] Table 2

[0191]

[0192] Table 2 (continued)

[0193]

[0194] Figure 3 , Figure 4A and Figure 4B Differential scanning calorimetry (DSC) curves for various asphalt samples (e.g., samples 1, 8, and 14) depict the heat flux (W / g) of the asphalt samples operated in air in an open pan as a function of temperature (°C). The initiation of oxidation is reflected by a sudden exothermic reaction at this temperature, due to the chemical reaction between the asphalt and air. For sample 1 (see Table 1 and...), further details are provided. Figure 3 Oxidation begins at approximately 252°C at OOT1. The T of sample 1... sp The temperature is 170°C, indicating that the pitch (sample 1) will melt before reacting with air (at a temperature of 252°C). These results suggest that the pitch of sample 1 is unsuitable for spinning into carbon fibers because the quality of the carbon fibers would be compromised during the stabilization process.

[0195] Regarding samples 8 and 14 (see Table 1 and...), Figure 4A ), T of sample 8 sp It is 313.2℃, and the T of sample 14 is... sp It is 323.2℃. However, the DSC curves of samples 8 and 14 show two exothermic phenomena. In fact, as shown in Table 1 and Figure 4A As shown, oxidation of sample 8 begins at approximately 186°C at OOT1 and approximately 325°C at OOT2, while oxidation of sample 14 begins at approximately 198°C at OOT1 and approximately 333°C at OOT2. For these two samples, the difference T... sp -OOT1 (°C) is a positive value, indicating that the integrity of the carbon fiber was not compromised during the stabilization process. Similarly, the initiation of oxidation is reflected by a sudden exothermic reaction at the stated temperature, due to the exothermic reaction between the pitch (samples 8 and 14) and air. Without being bound by any theory, it is assumed that the second exothermic reaction (OOT2) is due to the reaction between the mesophase pitch and oxygen in the air. Therefore, for a specific pitch, and at a specific rate of temperature change (e.g., 10°C / min), the exothermic reaction with air will occur at the specific temperature at which oxidation begins. Figure 4B These are differential scanning calorimetry (DSC) curves showing the heat flux (W / g) of samples 1 and 8 as a function of temperature (°C) when operated in air in an open dish.

[0196] exist Figure 5 The study further demonstrated the effect of oxygen (air) on the exothermic reaction of asphalt through a control experiment, which compared the results of DSC detection in air with those in nitrogen. Figure 5 The differential scanning calorimetry (DSC) curve showing the heat flux (W / g) of asphalt (sample 6) operated in an open pan in air as a function of temperature (°C) is compared with the DSC curve showing the heat flux (W / g) of the same asphalt (sample 6) operated in nitrogen as a function of temperature (°C). This DSC result clearly demonstrates that the heat originates from the reaction of the asphalt with air (sample 6). If the exothermic reaction were due to the oligomerization of reactive olefins, an exothermic reaction would be expected in nitrogen. However, no exothermic reaction occurred in nitrogen. Therefore, the DSC measurement provides information on how the asphalt responds during the stabilization process.

[0197] Figure 6 This is a thermogravimetric analysis (TGA) plot showing the weight loss of various asphalt samples (e.g., samples 1, 2, and 8) with temperature (°C). Figure 7 This shows the weight loss of various asphalt samples (e.g., samples 1, 2, and 8) with respect to the volatile formation temperature and softening point (T) as recorded by TGA measurements. sp Thermogravimetric analysis (TGA) plot showing the variation of temperature difference (ΔT, °C) between the two points.

[0198] Figure 6 This is a TGA graph showing the weight loss (wt%) of samples 1, 2, and 8 as a function of temperature (°C) at a temperature change rate of 10°C / min. This shows the relationship between the percentage weight change of asphalt and the increase in temperature. Therefore, Figure 6 This demonstrates that the amount of volatiles changes with temperature, and Figure 7 This reveals the variation of volatile matter content (wt%) with the softening point of asphalt. Figure 7 This shows the weight loss of various asphalt samples (e.g., samples 1, 2, and 8) with respect to the volatile formation temperature and softening point (T) as recorded by TGA measurements. sp The TGA graph shows the variation of the temperature difference (ΔT, °C) between the spinning temperature and the fiber temperature. As a result, a low-volatile bitumen content is required at the spinning temperature to prevent fiber breakage during spinning. In at least one embodiment, the bitumen should be at T... sp -30℃ and T sp Spinning at temperatures between +80°C and 80°C. For example... Figure 6 and Figure 7 As shown, samples 1 and 2 are suitable for spinning into their respective carbon fibers at a temperature 30°C higher than their softening point. However, samples 1 and 2 do not provide effective stabilization to their respective carbon fibers. Furthermore, Figure 6 and Figure 7 The results shown indicate that Sample 8 is a suitable pitch that allows the corresponding carbon fibers to operate well during the stabilization process. However, this pitch will need to be compared with T... sp Spinning at a temperature approximately 20°C higher, rather than at a temperature higher than T. sp Spinning at a temperature 30°C higher.

[0199] All references mentioned herein are incorporated to practice to the extent that they do not contradict this disclosure, including any priority documents and / or experimental procedures. It will be apparent from the foregoing general description and specific embodiments that various changes may be made without departing from the spirit and scope of this disclosure, despite the invention being described and shown. Therefore, this disclosure is not limited thereto. For example, a composition described herein may not contain any component or composition not expressly described or disclosed herein. Any method may omit steps not described or disclosed herein. Similarly, the term “comprising” is a synonym for the term “including.” When the conventional word “comprising” precedes a method, composition, element, or group of elements, it should be understood that we also contemplate the same composition or group of elements preceded by the conventional phrases “consistently of,” “composed of,” or “is,” or vice versa.

[0200] When references are made herein to numerical ranges having a lower and upper limit, any numerical value and any range within that range are specifically disclosed, including both the lower and upper limits. In particular, each numerical range disclosed herein (or in the form of “about a to about b,” or equivalents such as “from about a to b” or “about a to b”) should be understood to encompass every numerical value and range within a wider numerical range. Similarly, the language used in the claims has its plain, conventional meaning unless otherwise explicitly defined by the patentee. Furthermore, the indefinite pronouns “a” or “an” in the claims are defined herein as indicating one (an) or more than one (more than one) of the stated elements.

[0201] Therefore, the disclosure herein is well-suited for achieving the purposes and inherent advantages mentioned herein. The specific embodiments described above are merely illustrative, and those skilled in the art can modify and implement this application in various equivalent ways with the benefits taught herein. Furthermore, there are no limitations on the details of the structures or designs shown herein, except as described in the appended claims. Therefore, the specific exemplary embodiments disclosed above are obviously subject to variation, combination, or modification, and all such variations are considered to be within the scope and spirit of the disclosure herein. The embodiments disclosed herein can be suitably implemented in the absence of any factors not specifically disclosed herein and / or any non-essential factors disclosed herein.

Claims

1. A pitch composition suitable for spinning, comprising: Asphalt, wherein the asphalt has a softening point temperature of 400°C or lower (T sp ) and has a higher temperature ratio than T at a temperature change rate of 10°C / min. sp Oxidation onset temperature (OOT) at least 10°C lower, The bitumen contains more than 5% by volume of mesophase based on the total volume of bitumen.

2. The bitumen composition of claim 1, wherein the bitumen has a volatile content of 1% or less by weight based on the total weight of the bitumen at the spinning temperature.

3. The asphalt composition of claim 1, wherein the asphalt has a softening point temperature (T0) of 275-400°C. sp ).

4. The bitumen composition according to any one of claims 1 to 3, wherein the bitumen has a second OOT in the range of 200°C to 400°C.

5. The bitumen composition according to any one of claims 1 to 3, wherein the bitumen is used at a spinning temperature and / or at 0 to 100 s -1 It has a maximum critical stress of 100 Pa to 10,000,000 Pa at tensile strain rates.

6. The bitumen composition of claim 4, wherein the bitumen is at a spinning temperature and / or at 0 to 100 s -1 It has a maximum critical stress of 100 Pa to 10,000,000 Pa at tensile strain rates.

7. Fibers, oxidized fibers, carbonized fibers, graphitized fibers, fiber webs, oxidized fiber webs, carbonized fiber webs, or graphitized fiber webs prepared using the asphalt composition according to any one of claims 1 to 6.

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