Carboxymethylcellulose nano (CMCNa) is an ionic polymer cellulose etherate, commonly referred to as CMC. CMC is made from pulp or fine cotton. In a kneader, ethanol is used as a medium, and sodium hydroxide, chloroacetic acid (or sodium chloroacetate) is used for alkalization and etherification. Then, the product is obtained by neutralizing, washing, centrifuging sterol, drying, pulverizing, inspecting, and mixing and packaging.
CMC is a colloid that can be dissolved in both cold and hot water. Its aqueous solution has a very high transparency and fluidity and can form a stable network at different temperatures. It is both a strong dispersant and a binder, and a water retaining agent that acts as an emulsifier. Due to these excellent and specific properties, CMC has attracted the attention of the majority of paper workers and is widely used in the production of paper and cardboard.
It is mainly used for wet-end addition to improve paper formation and strength (breaking resistance and stiffness). Adhesives are used on the surface to improve the surface strength and smoothness of paper and paperboard and to improve the ink and water absorption of paper. It is used for paper coating to improve the water retention value of the coating, prevent the migration of the adhesive, and impart good stability to the coating, thereby improving the rheology of the coating and improving the coating quality.
In view of the unique and excellent performance of CMC, in actual production, we should reasonably select CMC according to the production conditions of the coated paper machine, such as the speed of the coating, the coating method, the solid content of the coating and the quality requirements of the product.
Generally high solid content (55-60) and high speed coating can choose CMC with viscosity in the range of 10 to 50 mPas. Low solid content (35-50) and low vehicle speed can be selected with a viscosity higher than 50-100mPas. The general amount of CMC is controlled at 0.5-2‰. It can be adjusted according to the actual situation, and even the dosage can be as high as 3‰. In short, with the rapid development of China's paper industry, lightweight coating technology is widely used. The application of CMC in the paper industry will also be further recognized. Although China's CMC industrial production started later than some developed countries, with the continuous deepening of China's opening up, the exchange activities of researchers at home and abroad increased. The CMC manufacturing technology has been further improved, and the gap with foreign products has been significantly shortened.