hydroxyethyl cellulose cas number

Hydroxyethyl Cellulose A Comprehensive Overview

Hydroxyethyl cellulose (HEC) is a non-ionic, water-soluble polymer derived from cellulose, a naturally occurring carbohydrate found in plant cell walls. Due to its unique properties, HEC has found applications across various industries, making it a versatile component in formulations ranging from cosmetics to pharmaceuticals.

Chemical Structure and CAS Number

Hydroxyethyl cellulose is characterized by the substitution of hydroxyl ethyl groups onto the cellulose backbone. The incorporation of these hydroxyethyl groups enhances the solubility of cellulose in water, thereby overcoming the inherent insolubility of native cellulose. The chemical formula for HEC can be represented as \( (C_2H_6O)_n \) where \( n \) indicates the degree of polymerization. The Chemical Abstracts Service (CAS) number assigned to hydroxyethyl cellulose is 9004-62-0, which is a unique identifier used to locate specific substances within databases and regulatory documents.

Production Process

The production of hydroxyethyl cellulose involves the reaction of cellulose powder with ethylene oxide in a controlled environment. The process begins with the treatment of cellulose with a strong base to activate the hydroxyl groups, which facilitates the etherification reaction. The introduction of ethylene oxide subsequently yields hydroxyethyl cellulose through the formation of ether linkages. This method results in varying degrees of substitution (DS), which is critical in determining the properties and applications of the resulting HEC.

Properties

HEC possesses several advantageous properties that make it suitable for a wide range of applications

1. Water Solubility HEC readily dissolves in water, forming a clear, viscous solution. This property makes it an ideal thickening agent for various formulations.

2. Thickening and Gelling HEC can thicken solutions and provide a gel-like consistency, which is beneficial in cosmetic and personal care products.

3. Temperature Stability HEC solutions exhibit stability across a broad temperature range, making it suitable for applications that may involve temperature fluctuations.

4. Biocompatibility As a derivative of cellulose, HEC is considered safe and non-toxic, which is essential for use in personal care and pharmaceutical products.

5. Film-Forming Ability HEC can form cohesive films, making it useful in formulations that require a protective barrier.

Applications

HEC's diverse properties enable its utilization across numerous industries

1. Cosmetics HEC is commonly used in shampoos, conditioners, creams, and lotions as a thickening agent, stabilizer, and film former. It enhances texture and improves the application and spreadability of products.

2. Pharmaceuticals In the pharmaceutical industry, HEC serves as a binder in tablet formulations and as a thickening agent in topical creams and gels. Its biocompatibility and non-toxic nature make it a preferred choice for drug delivery systems.

3. Food Industry HEC is utilized as a food additive, where it acts as a thickener, stabilizer, and emulsifier. It helps in maintaining texture and consistency in food products.

4. Construction In the construction industry, HEC is used in tile adhesives, plasters, and paints as a water-retaining agent, which helps in delaying the evaporation of water, thus improving adhesion and workability.

5. Oil and Gas HEC is also employed in hydraulic fracturing fluids and drilling muds due to its thickening properties, which assist in carrying proppants and controlling fluid loss.

Environmental Aspects

As a cellulose derivative, HEC is biodegradable and considered environmentally friendly, especially when compared to synthetic polymers derived from petrochemicals. Its usage aligns with the growing trend towards sustainability in various industries, where there is a push for greener alternatives to conventional materials.

Conclusion

Hydroxyethyl cellulose is a multifaceted compound with a strong presence across multiple sectors. Its unique properties, such as water solubility, thickening ability, and biocompatibility, make it an invaluable ingredient in formulations for cosmetics, pharmaceuticals, food, and beyond. As industries continue to embrace sustainable materials, the relevance of HEC is likely to grow, securing its place as a crucial player in the future of manufacturing and product development. Whether as a thickening agent or a gelling agent, hydroxyethyl cellulose will remain an essential component in the quest for innovative and effective solutions across diverse applications.