Properties
It is an important variety of non-ionic cellulose mixed ether. It is odorless, tasteless and non-toxic, and the finished product is white powder or loose fiber, and the particle size passes through 80 mesh sieve. It does not react with heavy metals. The proportion of methoxy content and hydroxypropyl content in the finished product is different, and the viscosity is different, so it becomes the varieties with different performance.HPMC is actually a kind of methyl cellulose modified by epoxy methane (methoxypropyl ring), so it has the similar characteristics of methyl cellulose that can be soluble in cold water and insoluble in hot water, and the solubility in organic solvent is better than the water solubility, which can be soluble in anhydrous methanol and ethanol, and also soluble in chlorinated hydrocarbons such as dichloromethane and other chlorinated hydrocarbons, such as dichloromethane. It is soluble in anhydrous methanol and ethanol, and also soluble in chlorinated hydrocarbons such as dichloromethane, trichloroethane, and organic solvents such as acetone, isopropyl alcohol, and bis-acetone alcohol.
Preparation method
There are two types of industrial preparation of HPMC: batch and continuous. Intermittent is the cellulose alkaline treatment, after pressing, crushing, maturing, and etherification reaction with etherifier in the autoclave to make crude products. Continuous type is not necessary to press, crushing and ripening, alkalization after high-pressure pipeline reactor for etherification reaction, continuous in and out of the material. HPMC preparation is mostly used in the liquid-phase method, because of the uniformity of the finished product obtained by this method is good. Preparation of alkali cellulose with the general 35% to 50% of the lye, cellulose and lye mass ratio of 1: (0.5-2.6).
Uses
In the polymerization reaction of synthetic resin, HPMC can be used as dispersant and suspending agent in the polymerization reaction of vinyl chloride and its copolymer; emulsifier in the copolymerization of dichloro vinyl acetate; suspending stabilizer in the copolymerization of vinyl acetate and vinyl chloride; stabilizer in graft copolymerization of butadiene, acrylonitrile, styrene, and so on. It can be used as additives in pharmaceutical and food industries, with the effects of thickening, solidifying, film-forming, dispersing, stabilizing, etc. It also has the functions of moisture-proof, mildew-proof, and moisture-retaining. In the paint industry, it can be used as emulsifier, thickener, film-forming agent and stabilizer. In the photosensitive printing plate, it is mainly used for film-forming and photodegradation, and it can be used for rapid development with water. As a detergent, it can improve the stain resistance of fabrics.
Safety
This product is non-toxic. Finished products are packed in kraft paper 3-in-1 composite bags lined with polyethylene film bags, 25kg per bag, or according to user requirements. Store in dry, ventilated and clean storehouse, away from heat source and avoid direct sunlight. Transportation should be prevented from sunshine and rain.
Molding processing
The solution is evenly coated on the platform, after drying, the film products can be made, the products are transparent and flexible.