Polyacrylamide (100 PAM) is a water-soluble linear polymer polymerized by acrylamide (AM) monomer initiated by the base. It has good flocculation, can resist between the two, according to the ionic characteristics. It can be divided into four types: non-ionic, anionic, cationic and amphoteric.
The function and characteristics of polyacrylamide:
1. Flocculation. PAM can make the suspension pass through the electric neutralization, and play a flocculating effect.
2. Adhesion. It can play a binding role through physical and chemical effects.
3. Thickener. It has a thickening effect under neutral and acidic conditions. If the PH value is above 10, PAM is easy to hydrolyze.
There are many factors that affect the amount of sludge dewatering polyacrylamide, such as Whether the sludge is fresh, the ash content, etc.; it is also related to the content of suspended solids in the sewage, the type of flocculant, temperature, and PH value. In addition, the choice of flocculant and sludge dewatering equipment is very important; the specific amount of dry mud per ton should be determined according to small tests, and the mud quality of each factory is different. The polyacrylamide products produced by Mitsubishi Chemical are used as the raw material of the paint mist aggregating agent b in the paint mist aggregating agent. The effect is outstanding, the cost-effectiveness is higher, the quality is relatively slow, and the degradation rate is relatively slow. Many manufacturers of paint mist agglutinants choose high Molecular weight polyacrylamide is used as the raw material for the production of paint mist agglutinant B, and it is the agent of paint remover manufacturer.
As the monomer acrylamide undergoes chain transfer to produce branched chains when it is polymerized, the PAM polymer chain structure contains a cross-linked structure mainly consisting of branched chains and imine bridges. Moderate cross-linking means that the relative molecule is high and easy to dissolve, while more cross-linking means that the product is insoluble. If the association of molecular chains is weakened, the glass transition temperature of PAM will be easier to dissolve. After adding low-molecular-weight amide compounds (such as urea), the interchain association of PAM can be weakened, thereby dissolving PAM. In addition, urea also has functions such as product cross-linking and PAM relative molecules. The preparation of high relative molecular PAM is the goal pursued, but the larger the relative molecule, the more branched chains, so it is difficult to dissolve 100 PAM. Degree of hydrolysis of PAM: The dissolution of PAM can be carried out under moderate hydrolysis, the greater the degree of hydrolysis, the more soluble. PAM is easy to decompose at greater than 200°C. Under 210°C anaerobic conditions, the amide group in PAM is dehydrated and transformed; at 500°C, polyacrylamide PAM is carbonized into black powder. The amide group in the PAM molecule has high known activity, including various properties such as thickening, flocculation and resistance reduction. PAM: Toxicity: PAM itself, but because polyacrylamide PAM retains acrylamide in the molecule, and acrylamide is toxic, the residual amount of acrylamide in polyacrylamide PAM is generally allowed to be 1%. Used in water purification, sucrose juice clarification and other food and esophagus paper, and the residual acrylamide in polyacrylamide PAM should be less than 0.05%.
Because of the anionic Polyacrylamide water purifier contains a certain amount of polar groups in its molecular chain, which can adsorb solid particles suspended in water, thereby bridging between particles to form large flocs, thereby accelerating the sedimentation of particles in suspension, which is obvious It makes the solid particles in the solution flocculate and settle, so that the solution is clarified, and the filtration is promoted.