Preparation method for improving lignin-based carbon fiber strength

A lignin-based and lignin-based technology, which is applied in the field of preparation of lignin-based carbon fiber strength, can solve the problems of poor tensile strength and tensile modulus, so as to improve tensile strength and modulus, increase crystallinity and The effect of density and structural stability

Inactive Publication Date: 2017-11-07
DEYANG LIJIU YUNZHI KNOWLEDGE PROPERTY OPERATIONS CO LTD
View PDF0 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The object of the present invention is to overcome the disadvantages of poor tensile strength and tensile modulus of lignin-based carbon fibers obtained by existing preparation methods, and provide a preparation method for improving the strength of lignin-based carbon fibers; the present invention not only pre-processes lignin treatment, so that the lignin molecular chains are rearranged and combined to form a regular and orderly pretreated lignin; also by densifying the lignin-based carbon fiber precursors, the structural defects of the fibers are repaired and the fiber density is increased, thereby enabling Carbonization to obtain lignin-based carbon fibers with higher tensile strength and tensile modulus

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] 1. After uniformly dispersing 100g of lignin in water, add 0.05g of a mixed enzyme consisting of lignin peroxidase, manganese peroxidase and laccase in a ratio of 2:1:1. Perform degradation treatment at a temperature of 25°C for 2 hours to form a mixed solution;

[0036] 2. Add 4g of sodium hydroxide to the mixed solution, react for 20min, then add 3g of sodium hypochlorite for oxidation treatment for 30-60min;

[0037] 3. Add 6 g of citric acid to the mixed solution after oxidation treatment, carry out polymerization reaction at a temperature of 95° C. for 6 hours, separate, purify, and dry to obtain pretreated lignin after the reaction is completed;

[0038] 4. Melt spinning the pretreated lignin at a temperature of 300°C to obtain lignin-based carbon fiber precursors;

[0039]5. Pre-oxidize the lignin-based carbon fiber precursor at a temperature of 350°C for 2 hours;

[0040] 6. Densify the pre-oxidized lignin-based carbon fiber precursors at a temperature of 360°...

Embodiment 2

[0043] 1. After uniformly dispersing 100g of lignin in water, add 0.01g of lignin peroxidase, and degrade at 35°C for 3 hours to form a mixed solution;

[0044] 2. Add 3g of potassium hydroxide to the mixed solution, react for 30min, then add 5g of potassium hypochlorite for oxidation treatment for 60min;

[0045] 3. Add 5 g of tartaric acid to the mixed solution after oxidation treatment, carry out polymerization reaction at 100° C. for 4 hours, separate, purify, and dry to obtain pretreated lignin after the reaction is completed;

[0046] 4. Melt spinning the pretreated lignin at a temperature of 280°C to obtain lignin-based carbon fiber precursors;

[0047] 5. Pre-oxidize the lignin-based carbon fiber precursor at a temperature of 320°C for 3 hours;

[0048] 6. Densify the pre-oxidized lignin-based carbon fiber precursors at a temperature of 350°C and a pressure of -15KPa for 5 hours;

[0049] 7. Carbonizing the densified lignin-based carbon fiber precursors at a temperat...

Embodiment 3

[0051] 1. After uniformly dispersing 100g of lignin in water, add a mixed enzyme consisting of 0.03g of lignin peroxidase and 0.07g of manganese peroxidase, and perform degradation treatment at 20°C for 2 hours to form a mixed solution;

[0052] 2. Add 2g of sodium hydroxide and 3g of calcium hydroxide to the mixed solution. After reacting for 15 minutes, add 2g of sodium hypochlorite and 3g of calcium hypochlorite for oxidation treatment for 30 minutes;

[0053] 3. Add 8 g of formic acid to the mixed solution after oxidation treatment, carry out polymerization reaction at a temperature of 85° C. for 8 hours, separate, purify, and dry to obtain pretreated lignin after the reaction is completed;

[0054] 4. Melt spinning the pretreated lignin at a temperature of 320°C to obtain lignin-based carbon fiber precursors;

[0055] 5. Pre-oxidize lignin-based carbon fiber precursors at a temperature of 380°C for 1 hour;

[0056] 6. Densify the pre-oxidized lignin-based carbon fiber p...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a preparation method for improving lignin-based carbon fiber strength. Lignin-based carbon fiber is obtained by conducting degradation, oxidation, polymerization, spinning, pre-oxidization, densification and carbonization treatment on lignin; according to the preparation method, the lignin is rearranged and recombined, lignin structural units are arranged neatly and orderly, few branched chains exist, and the structure is stable; structure defects of fiber are overcome by means of densification treatment, the density of protofilament is further increased, and then the tensile strength and modulus of the lignin-based carbon fiber are improved; the method is simple, reliable and practical, and the strength of the lignin-based carbon fiber can be improved significantly.

Description

technical field [0001] The invention relates to the field of carbon fiber materials, in particular to a preparation method for improving the strength of lignin-based carbon fibers. Background technique [0002] Carbon fiber (CF for short) is a new fiber material with high strength and high modulus with a carbon content of more than 95%. It is a microcrystalline graphite material obtained by stacking organic fibers such as flake graphite microcrystals along the axial direction of the fiber, and undergoing carbonization and graphitization. Carbon fiber has many excellent properties, such as high axial strength and modulus, low density, high specific performance, no creep, ultra-high temperature resistance in non-oxidizing environment, good fatigue resistance, specific heat and electrical conductivity between non-metal and Between metals, the coefficient of thermal expansion is small and has anisotropy, good corrosion resistance, good X-ray permeability, good electrical and th...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): D01F9/17D01F11/14
CPCD01F9/17D01F11/14
Inventor 李红梅
Owner DEYANG LIJIU YUNZHI KNOWLEDGE PROPERTY OPERATIONS CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products