Polyacrylamide (PAM) is a polymer compound formed by polymerization of acrylamide monomer. It is widely used in water treatment, oil extraction, pulp and paper, textile, soil solidification and other fields. The exact synthesis method of polyacrylamide is not complicated, and the following is a brief introduction to the raw materials of polyacrylamide and how it is synthesized.
Acrylamide is the main raw material of polyacrylamide, which is a colorless crystal that is soluble in water and many organic solvents. The chemical structure of acrylamide monomer is as follows:
The preparation of acrylamide monomers generally goes through the following three steps:
Cyanidation: Acrylonitrile reacts with a base (such as sodium hydroxide) to form acrylamide.
Dehydration reaction: acrylamide is dissolved in water, stabilizer is added, and the reaction temperature, pressure and time are controlled.
Purification process: Through distillation, crystallization, filtration and other process steps, the product is purified to obtain acrylamide with high purity.
The acrylamide monomer is added to the reaction vessel, and the polymerization reaction is carried out under appropriate conditions through the action of an initiator. Polymerization reactions are generally divided into two methods:
The free radical polymerization method is to dissolve free radical initiators such as benzoyl peroxide (BPO) in an aqueous solution, and then add acrylamide monomer and carry out a reaction. Free radical initiators can produce free radical activity, trigger the free radical polymerization of acrylamide monomers, and finally form polyacrylamide.
Anionic polymerization is the process of mixing an aqueous solution (such as sodium hydroxide solution) with acrylamide monomer under alkaline conditions and heating it for a reaction. Under alkaline conditions, the acrylamide monomer is resalted into a conjugated base, and then through a heating polymerization reaction, the final polyacrylamide is formed.
Polyacrylamide is an important polymer compound, which is synthesized by polymerization reaction with acrylamide monomer as raw material. The preparation of acrylamide monomers usually undergoes a cyanide reaction, dehydration reaction, and purification process. The polymerization reaction mainly includes free radical polymerization and anion polymerization. The above is a brief introduction to the raw materials and synthesis methods of polyacrylamide.