Sodium carboxymethyl cellulose (CMC) is used as a sizing agent in the textile industry. Its core function is to improve the physical properties of yarns and enhance their resistance during the weaving process. This is specifically demonstrated in the following ways:
1. Forming a protective film and enhancing abrasion resistance
CMC is a water-soluble polymer that forms a uniform, tough, and flexible film on the yarn surface during sizing. This film encapsulates fiber hairiness, reducing fiber breakage and hairiness regeneration caused by friction during weaving (such as when the warp yarn passes through the heddle eye or reed dents, or when it rubs against the needles), thereby reducing yarn wear.
2. Improving yarn strength and tensile strength
Yarns (especially natural fiber yarns such as cotton and viscose) have low inherent strength and are easily broken by repeated stretching during weaving. CMC film tightly bonds with yarn fibers, binding loose fibers together through a "bonding" effect. This enhances the yarn's overall breaking strength and tensile deformation resistance, reduces end breakage during weaving, and improves weaving efficiency.
3. Improves Yarn Smoothness and Reduces Friction
The smooth surface of CMC film reduces friction between yarns and between yarns and weaving equipment (such as heald frames and reeds), ensuring smoother yarn flow during weaving and minimizing tension fluctuations and yarn damage caused by excessive friction.
4. Excellent Water Solubility, Facilitating Subsequent Desizing
After sizing textiles, desizing is necessary to remove the sizing to prevent interference with subsequent processing such as dyeing and printing. CMC has excellent water solubility, making desizing easy to remove with hot water or a weak alkaline solution, leaving no residual impurities. It is simple to use and environmentally friendly, making it particularly suitable for subsequent fabric processing requiring high cleanliness.
5. Good fiber compatibility, no damage to yarn properties
CMC's chemical structure is similar to that of cellulose fibers (cotton, linen, viscose, etc.), resulting in strong affinity. During sizing, it evenly penetrates and adheres to the yarn without damaging the fiber's physical or chemical properties, preserving the yarn's inherent moisture absorption and breathability.
In summary, CMC, as a sizing agent, significantly enhances yarn weaving suitability through its triple role of "protection, reinforcement, and lubrication." It is a key additive in the textile industry for improving weaving efficiency and fabric quality. It is particularly suitable for easily damaged yarn types, such as medium and low count yarns and short-staple yarns.
