Physicochemical Properties Of Polyacrylamide

- Sep 04, 2018-

PAM Polyacrylamide is an acrylamide (AM) monomer by free radical polymerization of water-soluble linear polymer, with good flocculation, can reduce the friction between the liquid, according to the ionic characteristics can be divided into non-ionic, anionic, cationic and bisexual four types. Polyacrylamide (PAM) is insoluble in most organic solvents, such as methanol, ethanol, acetone, ether, aliphatic hydrocarbons and aromatic hydrocarbons, with the exception of a few polar organic solvents, such as acetic acid, acrylic acid, chloroacetic acid, ethylene glycol, glycerin, molten urea and formamide.

But the solubility of these organic solvents is limited, often need to be heated, otherwise there is no significant application value. At a suitable low concentration, the polyacrylamide solution can be regarded as a network structure, the mechanical entanglement and hydrogen bonding between the chain to form a mesh node, the concentration is high, because the solution contains many chain a chain contact point, so that the PAM solution is gel-like. Pam aqueous solution with many can and water miscible organic matter has very good compatibility, the electrolyte has a good compatibility, to chlorinated amine, calcium sulfate, copper sulfate, potassium hydroxide, sodium carbonate, sodium borate, ammonium nitrate, phosphate, sodium sulfate, zinc chloride, boric acid and phosphoric acid and other substances are not sensitive. [2] polyacrylamide mesh Number: Mesh number refers to the size or thickness of the material, the mesh number is the number of squares per unit area. The general definition refers to the number of mesh holes in the area of 1 "* 1", that is, the number of mesh holes in the sieve mesh. If 600 mesh is every square inch has 600 square mesh hole, polyacrylamide mesh number 20 mesh ~80 mesh, namely 0.85mm~0.2mm, this is granular polyacrylamide's mesh size, the size of the mesh of the powder polyacrylamide can be controlled in 100 mesh, the greater the number of mesh, the more easily dissolved polyacrylamide,

The size of the polyacrylamide mesh alone cannot measure the quality of the product! Polyacrylamide is a white powder or small particles, the density of 1.32g/cm3 (23 degrees), the glass temperature of 188 degrees, softening temperature of nearly 210 degrees, the general method of drying with a small amount of water, dry and will quickly draw water from the environment, the freeze-drying separation of the homopolymer is white soft non-crystalline solid , but when precipitated from the solution and dried is a glassy part of the transparent solid, completely dry polyacrylamide Pam is brittle white solid, commercial polyacrylamide drying is usually under moderate conditions dry, general water content of 5%~15%, cast on the glass plate prepared by the polymer film, is transparent, hard, Fragile solids.

Toxicity: Polyacrylamide itself and its water disintegration is not toxic, the toxicity of polyacrylamide from its residual monomer acrylamide (AM). Acrylamide is a nerve-induced agent, has damage to the nervous system, after poisoning the apparent body weakness, motor disorders and other symptoms. Therefore, the national health departments have specified the acrylamide content in the Polyacrylamide industrial products, generally 0.5%---0.05%.

Polyacrylamide is used in industrial and municipal wastewater purification treatment, generally allow the acrylamide content of 0.2% or less, for direct drinking water treatment, acrylamide content should be under 0.05%.