Continuous polymerization kettle-starting method of polyacrylontrile precursor polymer solution

Abstract

The invention relates to a continuous polymerization kettle-starting method of a polyacrylontrile precursor polymer solution. Before a material enters into a polymerization reaction kettle, air is isolated through a protective gas so as to reduce the influence of air on the polymerization reaction; when the material accumulated in the polymerization reaction kettle reaches the upper surface of the temperature-measuring opening of the polymerization reaction kettle, temperature control is carried out on the polymerization reaction kettle, and polymerization temperature and continuous material feeding are controlled to be simultaneously carried out. According to the invention, the effects of continuously feeding the material and slowly polymerizing are realized through controlling the temperature of the polymerization reaction, thereby being beneficial to the elongation of polymerization reaction time, avoiding the defects that the heat release of the polymerization reaction is over rapid and the heat dissipation of the polymerization reaction kettle is not uniform and effectively inhibiting the generation of gel in the polymerization process; a continuously fed fresh material is in favor of balancing the heat of a polymerization reaction system so that a starting process is carried out under the relatively mild conditions, and the fluctuation of the property parameter of the polymer solution is little; and because the reaction conditions are relatively mild and easy to control from the starting of the kettle, the polymerization reaction system is stable, thereby shortening the time required from the starting of the kettle to the stabilization of the whole polymerization system.

Description

technical field [0001] The invention relates to a continuous polymerization method for continuous polymerization of carbon fiber precursors, in particular to a method for continuous polymerization of polyacrylonitrile-based carbon fiber precursors. Background technique [0002] Because of its high specific strength, high specific modulus, heat resistance, corrosion resistance, fatigue resistance, creep resistance and other excellent properties, carbon fiber is widely used as a reinforcing material in aerospace, national defense construction and other fields. Among them, polyacrylonitrile Carbon-based fibers are the most widely used and have the highest output. The main raw material of high-performance polyacrylonitrile-based carbon fiber is polyacrylonitrile precursor. The quality of the precursor determines the quality of the carbon fiber to a large extent, and the most fundamental reason affecting the quality of the precursor is the comprehensive performance of the polymer...

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Problems solved by technology

[0005] In order to overcome the disadvantages of intermittent polymerization and continuous polymerization with full kettle starting that the air cannot be completely isolated during the kettle opening process, gel is easily generated, and it takes a long time to stabilize the entire polymerization system from the kettle opening, the present invention proposes a polymerization Method for continuous polymerization of acrylonitrile precursor polymerization solution

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