Hydroxypropyl methylcellulose (HPMC) is a cellulose ether that is derived from natural cellulose. It is a synthetic, water-soluble, non-ionic polymer that is commonly used in various industries such as construction, pharmaceuticals, food, cosmetics, and textiles.
HPMC is produced by chemically modifying cellulose with propylene oxide and methyl chloride to introduce hydroxypropyl and methyl groups into the cellulose molecule. The degree of substitution (DS) of HPMC refers to the number of hydroxypropyl and methyl groups per anhydroglucose unit (AGU) of cellulose.
HPMC has several properties that make it useful in various applications. It is soluble in water, forms a clear solution, and has good thermal stability. It is also stable under normal conditions of temperature and pH and does not decompose easily. HPMC is hygroscopic, which means it can absorb and retain moisture. It is non-toxic, non-irritating, and non-allergenic, which makes it safe for use in many applications.
In the construction industry, HPMC is used as a thickener, binder, and water-retaining agent in cement-based products, tile adhesives, plasters, and other building materials. In the pharmaceutical industry, HPMC is used as a binder, disintegrant, and film-former in tablet and capsule formulations. In the food industry, HPMC is used as a thickener, emulsifier, and stabilizer in various products. In cosmetics, HPMC is used as a thickener, film-former, and emulsifier in creams, lotions, and other formulations.
Overall, HPMC is a versatile and useful polymer that has a wide range of applications in various industries due to its unique properties.