Physical Properties
Appearance: White powder or fiber.
Odor: Odorless.
Toxicity: Non-toxic.
Chemical Properties
Composition: Product of total or partial methylation of the three hydroxyl groups in glucose (cellulose).
Degree of Substitution (DS):
Fully methylated: DS = 3, methoxy content = 45.6%.
Typical product: DS = 1.7 to 2.2, methoxy content = 26% to 33%.
Solubility:
DS 1.3 to 2.6: Soluble in water, pyridine, and glacial acetic acid.
DS 2.4 to 2.8: Soluble in polar solvents.
Solubility depends on the uniformity of substituent distribution and degree of polymerization (lower polymerization = better solubility).
Functional Properties
Excellent moisturizing, dispersion, and stability properties.
Viscosity behavior:
Initially decreases with increasing temperature.
At a certain temperature, viscosity sharply increases, leading to gelation.
Safety and Reactivity
Forms explosive mixtures with air (powder).
Combustible: Can burn and explode when exposed to open flame or high heat.
Preparation method
Mix wood pulp or cotton pulp (cotton fluff), sodium hydroxide and water phase, and soak at about 30℃. Then press it to get plate-like alkali cellulose. It is crushed to loosen the tissue of alkali cellulose and make it further homogenized, and degraded by interaction with oxygen in the air to reduce the degree of polymerization in order to adjust the viscosity of the product. Etherification is then accomplished by adding an excess of chloromethane for reaction. Then the product is washed in hot water, after which hydrochloric acid (or sulfuric acid) and oxalic acid are added to decolorize the product, which is washed to neutral, and the finished product is obtained after dehydration and drying.
Uses
Used as dispersant for polyvinyl chloride. It is used as film-forming agent and adhesive in cosmetics, medicine and food industry, sizing agent for textile printing and dyeing, film-forming agent and thickening agent for paint. In the construction industry, it is used as mixing agent for cement, mortar and jointing cement.
Safety
The product is irritating to eyes and skin. Store in a cool, ventilated warehouse. Keep away from fire and heat. Keep the container sealed. Protect from sunlight. Should be stored separately from oxidizers.