What are the main applications of CMC in the papermaking industry?

(1) Introduction

Carboxymethyl Cellulose (CMC) is an important water-soluble polymer with high-efficiency thickening, film-forming, stabilizing and suspending properties. These properties make it a key additive in the papermaking industry. In the papermaking process, CMC is mainly used to improve paper properties, increase production efficiency and reduce production costs.

(2) Main applications of CMC in the papermaking industry

Application in pulp preparation

In the pulp preparation process, CMC is widely used to improve the suspension stability of pulp. Its good solubility and thickening ability can effectively improve the uniformity of pulp and prevent the precipitation of pulp particles. The use of CMC can enhance the bonding force between fibers in pulp, improve the filterability of pulp, and thus improve the molding quality of paper.

Application in papermaking process

In the papermaking process, CMC plays an important role as a wet end additive. Its main functions include:

Improving the formability of paper: CMC improves the formability of pulp by increasing the viscosity of pulp and the bonding force between fibers, making the paper structure more compact and uniform, and improving the surface quality and physical strength of paper.

Improving the retention rate of paper: CMC can increase the retention rate of fillers and fine fibers in pulp in the paper machine mesh, thereby reducing the loss of fillers and fibers and improving the composition consistency of paper.

Enhancing the dry strength of paper: CMC can improve the dry strength of paper, and even under low sizing conditions, it can significantly enhance the tensile strength, tear strength and bursting strength of paper.

Application in surface sizing

During the surface sizing process, CMC is used as a sizing agent to improve the surface properties of paper. The sizing paper has better printing adaptability and water resistance, and the surface smoothness and glossiness are also improved. The excellent film-forming properties of CMC enable it to form a uniform film on the surface of paper, enhancing the physical strength and smoothness of paper.

Application in coated paper

CMC is often used as a binder and thickener for coating materials in the production of coated paper. Its main functions include:

Improving the uniformity of the coating layer: CMC can effectively control the rheological properties of the coating material to ensure the uniformity and smoothness of the coating layer.

Enhancing the adhesion of the coating layer: CMC enhances the adhesion between the coating layer and the paper substrate, and improves the wear resistance and peeling resistance of the coating layer.

Improving printing adaptability: The use of CMC can improve the printing adaptability of coated paper, so that the paper can better absorb ink during the printing process, presenting a clearer and more vivid image.

Application in waste paper recycling

CMC also plays an important role in waste paper recycling. In the deinking process of waste paper, CMC can be used as a deinking agent to improve the dispersion and removal efficiency of ink particles in waste paper pulp, thereby improving the regeneration quality of waste paper pulp. In addition, CMC can also be used as a stabilizer to prevent precipitation and stratification of waste paper pulp during storage and transportation.

Application in specialty paper

For the production of specialty paper (such as waterproof paper, oil-resistant paper, etc.), CMC plays a unique role as a functional additive. By adjusting the dosage and use conditions of CMC, the special properties of paper, such as water resistance, oil resistance and antistatic properties, can be significantly improved. This makes CMC have a wide range of application prospects in the development and production of special paper.

(3) Advantages of CMC in the papermaking industry

Environmental protection: CMC is a polymer material of natural origin. No harmful substances are produced during its production and use, which meets the green environmental protection requirements of the papermaking industry.

High efficiency: CMC has significant thickening, stabilization and film-forming capabilities, and can achieve good use effects at a lower dosage, reducing papermaking costs.

Ease of use: CMC is easily soluble in water, adapts to various papermaking process flows, and has good compatibility with other papermaking chemicals.

Economic efficiency: Compared with other high-performance additives, CMC has a lower cost and can effectively reduce the production expenses of papermaking enterprises.

CMC has a wide range of applications in the papermaking industry, from pulp preparation to paper surface treatment, which can significantly improve the performance and production efficiency of paper. With the continuous development of papermaking technology, the application prospects of CMC will be broader, making an important contribution to the green and sustainable development of the papermaking industry. In the future, further developing and optimizing the functions of CMC and improving its application effects will be an important direction of technological innovation in the papermaking industry.