Process method for preparing intermediate phase lignin and carbon fibers thereof

Abstract

The invention relates to a process method for preparing intermediate phase lignin and carbon fibers thereof. The process method is characterized in that a condensing agent is added for carrying out heat treatment reaction modification and further condensation polymerization on various lignin to obtain a polycyclic aromatic hydrocarbon substance with an intermediate phase, the polycyclic aromatic hydrocarbon substance is prepared into the intermediate phase lignin, and the intermediate phase lignin can be used for preparing various carbon materials. The high-intensity and high-modulus lignin carbon fibers can be prepared by melt spinning, pre-oxidation and carbonization of the intermediate phase lignin prepared by the method, and is comparable with high-performance pitch-based carbon fibers and high-modulus polyacrylonitrile-based carbon fibers.

Description

technical field [0001] The invention relates to a production method of lignin carbon fiber, which is a production process of high-performance mesophase lignin and carbon fiber. Background technique [0002] Carbon fiber is a fibrous material with a carbon content of more than 90% by mass. It has various types. Its high strength and high modulus can be used to make various composite materials, which can be used as structural materials and have a wide range of applications. There are many ways to produce carbon fiber. At present, polyacrylonitrile-based carbon fiber accounts for more than 75% of the total, followed by pitch-based carbon fiber, while the global production of viscose-based carbon fiber only accounts for about 1%. [0003] Mesophase aromatics prepared from asphalt, naphthalene and other raw materials have the characteristics of high modulus, high thermal conductivity, and high electrical conductivity. They have a wide range of uses and can be used to produce high...

AI Technical Summary

Problems solved by technology

The alkali lignin and sulfonate lignin produced by traditional pulping and papermaking contain high content of inorganic substances, including impurities such as sodium, sulfur, calcium, magnesium, etc., which make the lignin carbon fiber performance poor, while ethanol lignin, acetic acid The performance of the carbon fiber produced by purifying and purifying lignin such as lignin and phenolic lignin can only reach the level of general-purpose. Its tensile strength is 300-900MPa, and its tensile modulus is about 40GPa. It cannot produce high-performance carbon fiber. Carbon fiber, and the production cost is high, so it is more difficult to use lignin carbon fiber

The wood liquefied product described in patent CN200710175769.7 is re-spun through a synthetic agent to make resin carbon fiber. The carbon structure cannot form the sheet structure of graphite, and the strength is low and the use is limited.

The carbonaceous mesophase produced from biomass described in patent CN02151063.6 has no fluidity and spinnability, and cannot be made into carbon fibers