Method for improving strength of polyacrylonitrile-based carbon fibers

A polyacrylonitrile-based carbon fiber, strength technology, applied in the chemical characteristics of fibers, textiles and papermaking, etc., can solve the problem of no technical reports, and achieve the effect of reducing water absorption, simple control, and improving tensile elastic modulus

Active Publication Date: 2018-04-06
CHINA PETROLEUM & CHEM CORP +1
View PDF6 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, for the voids and defects on the surface and interior of the fiber caused by the moisture brought by the ambient temperature and

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for improving strength of polyacrylonitrile-based carbon fibers
  • Method for improving strength of polyacrylonitrile-based carbon fibers
  • Method for improving strength of polyacrylonitrile-based carbon fibers

Examples

Experimental program
Comparison scheme
Effect test

Example

[0030] [Examples 1-12]

[0031] Follow the steps below to prepare carbon fiber:

[0032] 1) After warping, the polyacrylonitrile precursor yarn enters into the 1# oxidation furnace at 225 and 232℃ in sequence at 5.5m / min and a certain tension (225 and 232℃ are the control temperatures of the two temperature zones of 1# furnace respectively. The same below), then enter 2# oxidation furnace with temperature of 238, 245℃, and finally into 3# oxidation furnace with temperature of 253, 263℃, the residence time in the furnace is 95min; the temperature of the end zone of the oxidation furnace in each embodiment See Table 2.

[0033] 2) The pre-oxygen wire from the 3# oxidation furnace is drawn by the exit traction roller into the first constant temperature and humidity chamber. Compressed air with a pressure of 0.6 MPa and a dew point of -40°C is introduced into the room, the pressure in the constant temperature and humidity room is controlled to be normal pressure, and the exit traction ...

Example

[0038] [Comparative Examples 1~4]

[0039] Follow the steps below to prepare carbon fiber:

[0040] 1) After warping, the polyacrylonitrile precursor yarn enters into the 1# oxidation furnace with a temperature of 225~232℃ in sequence at 5.5m / min and a certain tension, and then into the 2# oxidation furnace with a temperature of 238 and 245℃, and finally enters the temperature In the 3# oxidation furnace at 253 and 263℃, the residence time in the furnace is 95min; the temperature of the end zone of the oxidation furnace in each comparative example is shown in Table 2.

[0041] 2) The pre-oxygen wire from the 3# oxidation furnace is drawn into the low-temperature carbonization furnace by the exit traction roller, and the end gas seal of the low-temperature carbonization furnace is sealed with high-purity nitrogen at a temperature of 100-200℃. The temperature of the furnace cavity is controlled in 7 temperature zones, and the temperature of 1#~6# zone is set in steps between 400~760℃....

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 method for improving strength of polyacrylonitrile-based carbon fibers. The method comprises the following steps: enabling polyacrylonitrile-based carbon fibers to immediately enter an environment with controlled temperature and humidity after tows are discharged out of an oxidizing furnace and a low-temperature carbonized furnace, so that a series of moisture absorptioneffects generated after the tows enters the humid environment are avoided; and enabling moisture absorbed after the tows enter the opening of the low-temperature carbonized furnace to be instantaneously gasified and bound to carbon atoms in the fibers, and releasing CO and other gases, so that defects or holes are reserved on the surfaces of the tows or inside the tows, and the strength and otherperformances of the fibers are reduced. According to the method disclosed by the invention, fluctuations brought to the strength and other performances of the carbon fibers due to changes of the temperature and humidity of the environment can be avoided, so that the prepared carbon fibers have excellent performances such as small quantity of holes, uniform quality, low discrete property, high strength and the like.

Description

technical field [0001] The invention relates to the technical field of carbon fibers, in particular to a method for improving the strength of polyacrylonitrile-based carbon fibers. Background technique [0002] Carbon fiber is a new type of high-strength, high-modulus fiber material with a carbon content of more than 95%. Between non-metal and metal, it has small coefficient of thermal expansion and anisotropy, good corrosion resistance, good X-ray permeability, good electrical and thermal conductivity, electromagnetic shielding, etc. It is important in national defense and civilian applications Material. It not only has the inherent intrinsic characteristics of carbon materials, but also has the softness and processability of textile fibers. It is a new generation of reinforcing fibers. [0003] Structurally speaking, carbon fiber is a microcrystalline graphite material obtained by stacking organic fibers such as flake graphite microcrystals along the fiber axis and under...

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
IPC IPC(8): D01F9/22
CPCD01F9/22
Inventor 顾文兰宋文迪吴嵩义
Owner CHINA PETROLEUM & CHEM CORP
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap