Phenol ketone products

Plastic rubber

Current Location： Home > News > Chemical Knowledge > Production process and preparation method of polyacrylonitrile

[Chemical Knowledge]：Production process and preparation method of polyacrylonitrile

Read： 949 Time：18months ago Source：Transform the World with Simplicity

Polyacrylonitrile is a kind of polymer material, which has excellent mechanical properties, thermal stability and chemical resistance, and is widely used in various fields. This article will introduce the production process and preparation method of polyacrylonitrile.

1. production process

polyacrylonitrile production process usually uses solution polymerization and suspension polymerization two methods.

1. solution polymerization

solution polymerization method is to mix acrylonitrile, solvent and initiator to form a uniform solution, after heating to a certain temperature, the initiator begins to catalyze the polymerization reaction, polymerization of polyacrylonitrile. The biggest advantage of the solution polymerization method is that the composition of the material and the reaction temperature can be controlled during the polymerization process, so as to obtain polyacrylonitrile with different properties. After the solution polymerization, the remaining solvent is removed by evaporation or extraction.

2. Suspension polymerization

suspension polymerization method is to mix acrylonitrile and initiator into the system composed of water and surfactant to form tiny droplets, and polymerization reaction is carried out on the surface of the droplets, and finally polyacrylonitrile particles are generated. The advantages of suspension polymerization are fast reaction rate, uniform polymerization product particles, simple operation, etc., but it is difficult to accurately control the reaction process.

2. preparation method

The preparation method of polyacrylonitrile is mainly divided into three steps: pretreatment, polymerization reaction and polymer treatment.

1. Pretreatment
The purpose of
pretreatment is to remove impurities from the feedstock and to reduce by-products from the polymerization process. The pretreatment steps generally use filtration, distillation, etc.

2. Polymerization

polymerization is the core step in the preparation of polyacrylonitrile. The specific method and production process vary slightly according to the polymerization method.

In solution polymerization, acrylonitrile, reaction solvent and initiator are mixed in a certain proportion, and the reaction is carried out at high temperature. The reaction time is generally between several hours and ten hours. After completion of the polymerization reaction, the reaction solution was cooled to room temperature.

In suspension polymerization, acrylonitrile and initiator are mixed in water to form tiny droplets. With the gradual growth of the polymerization reaction, the droplets gradually aggregate, and finally the particles are separated by filtration or precipitation.

3. processing polymer

processing polymer is the polymerization of polyacrylonitrile for loose, recovery and drying and other processing, so that the polymer can be applied to various fields.