Polyacrylonitrile-based fiber, polyacrylonitrile-based carbon fiber and preparation methods

Abstract

The invention relates to polyacrylonitrile-based fiber, polyacrylonitrile-based carbon fiber and preparation methods of the polyacrylonitrile-based fiber and the polyacrylonitrile-based carbon fiber. The preparation method of the polyacrylonitrile-based fiber comprises the following steps of carrying out first oiling treatment on fiber to be oiled to obtain first oiled fiber; and carrying out drying densification treatment, steam drafting treatment, relaxation heat setting treatment and winding on the first oiled fiber to obtain the polyacrylonitrile-based fiber. Before the step of relaxation heat setting treatment, the fiber subjected to steam drafting treatment is subjected to second oiling treatment; and oil agents used for the first oiling treatment and the second oiling treatment are different. The polyacrylonitrile-based fiber is subjected to pre-oxidation, low-temperature carbonization and high-temperature carbonization treatment to obtain the polyacrylonitrile-based carbon fiber. The methods are mainly used for preparing high-strength and medium-modulus polyacrylonitrile-based fiber and polyacrylonitrile-based carbon fiber with excellent performance.

Description

Technical field [0001] The present invention relates to the field of carbon fibers, and more particularly to a polyacrylonitrile-based fiber, a polyacrylonitrile carbon fiber, and a preparation method thereof. Background technique [0002] Carbon fiber materials have high performance and low density of materials, which are typical military and civilian key materials leading the typical representative of the material revolution. The polypropylene-based fiber is the most promising precursor produced high-performance carbon fiber, and the comprehensive performance of carbon fibers prepared by polypropylene-based fibers is the best, and the production process is simple, and its yield accounts for more than 90% of current world carbon fiber production. Polypropylene-based fiber preparation techniques are the core prepared by polyacrylonitrile carbon fibers. At present, countries that produce carbon fibers are increasing the mass of polypropylene-based fibers and the mechanical propert...

AI Technical Summary

Problems solved by technology

If the amount of oiling is too small or the uniformity of oiling is not good, a uniform oil film cannot be formed on the surface of the monofilament, and the fiber cannot be effectively protected, which will cause adhesion or paralleling between the monofilaments, but the amount of oil is too much, or the oil agent is selected Improper penetration into the inner layer of the fiber will cause serious silicon pollution and reduce the tensile strength of carbon fibers. Therefore, exploring suitable oiling agents and oiling processes is the key to improving the performance and quality of polyacrylonitrile-based fibers and polyacrylonitrile-based carbon fibers.