Product Introduction: Polyacrylamide for Papermaking
Polyacrylamide for papermaking is a white, granular solid, linear polymer with a unique molecular structure. It appears as white powder, translucent beads, or flakes, exhibiting no odor or taste. This product boasts thermal stability and excellent solubility, capable of dissolving in water in any proportion to form a uniform and transparent liquid. In its dry state, the particles disperse without showing any adhesiveness. With a density of approximately 1.32g/cm³ at 23°C, a glass transition temperature of 188°C, and a softening temperature close to 210°C, polyacrylamide for papermaking demonstrates robust physical properties.
Physical Properties
Polyacrylamide for papermaking is characterized by its white powder form and a density of 1.32g/cm³ at 23°C. Its glass transition temperature stands at 188°C, while the softening temperature is nearly 210°C. When dried using conventional methods, it contains a small amount of water and quickly absorbs moisture from the environment. The homopolymer separated by freeze-drying is a white, fluffy, non-crystalline solid. However, when precipitated from solution and dried, it becomes a vitreous, partially transparent solid. Fully dried polyacrylamide (PAM) is a brittle, white solid. Commercially available polyacrylamide is typically dried under moderate conditions, with a moisture content ranging from 5% to 15%. Polymer membranes cast on glass plates are transparent, hard, and brittle solids.
Product Usage Characteristics
Flocculation: PAM can cause suspension particles to flocculate through electrical neutralization and bridging adsorption.
Adhesion: It exhibits adhesive properties through mechanical, physical, and chemical interactions.
Friction Reduction: PAM effectively reduces the frictional resistance of fluids, with the addition of trace amounts reducing resistance by 50-80% in water.
Thickening: PAM enhances thickness under neutral and acidic conditions. When the pH exceeds 10, PAM is prone to hydrolysis, forming a semi-network structure that further enhances thickening.
Industry Applications
In the papermaking industry, polyacrylamide is widely used as a retention aid, filter aid, and forming agent, improving paper quality, enhancing pulp dehydration performance, increasing the retention rate of fine fibers and fillers, and reducing raw material consumption and environmental pollution. Its effectiveness in papermaking depends on factors such as average molecular weight, ionic nature, ionic strength, and the activity of other copolymers. Non-ionic polyacrylamide primarily enhances pulp filtration, increases dry paper strength, and improves the retention rate of fibers and fillers. Anionic polyacrylamide copolymers serve as dry and wet strengtheners and retention aids for paper. Cationic polyacrylamide copolymers are primarily used for wastewater treatment and filtration assistance in papermaking, also effectively improving filler retention. Additionally, polyacrylamide for papermaking is applied in wastewater treatment and fiber recovery.
Specifically, Ciba Specialty Chemicals' polyacrylamide, as a cationic retention and filtration aid (e.g., C8560), is extensively used in the production of cultural paper, newsprint, cardboard, and specialty molded products. It is recommended to add it at the thin stock stage, preferably at the last shear point before sheet formation, with a dosage ranging from 0.01% to 0.1% (relative to oven-dried pulp). It can be used in single, dual, and micro-particle retention systems and as a polymeric flocculant to enhance the efficiency of the paper machine recovery system.
Advantages
Enhances the retention of fine fibers, CaCO3, TiO2, and kaolin in the wet end.
Provides a stable wet-end environment, improving paper formation and performance.
Improves drainage during sheet formation and pressing, reducing energy consumption in the drying process.
Reduces white water solids content, enhancing raw material yield and recovery system efficiency.
Broad pH adaptability, independent of aluminum sulfate use.
Certified by FDA and BGVV, suitable for producing paper and paperboard in contact with food.
Offers stable cationic charge in acidic, neutral, and alkaline systems.
Improves the retention of colloidal substances in the wet end, enhancing the efficiency of sizing agents and dyes.
Increases paper machine productivity and improves operational performance.
Contains no surfactant components, posing no harm to the environment.
Available in various packaging specifications.
Precautions
When using polyacrylamide for papermaking, ensure complete dissolution to prevent clogging of filters due to undissolved additives. Impurities such as plant fibers and additives that are insoluble in water can accumulate and block filtration equipment, reducing production efficiency. Pay attention to the solubility, viscosity, and dissolution time of polyacrylamide during production.
