Hydroxypropyl methylcellulose (HPMC) is a synthetic, water-soluble polymer derived from cellulose. It is a white, odorless, tasteless powder that is widely used as a thickening agent, emulsifier, film former, and stabilizer in many industries, including pharmaceuticals, food, cosmetics, and construction.
HPMC is made by reacting cellulose with propylene oxide and methyl chloride. Cellulose is a polysaccharide that is the main component of plant cell walls and is the most abundant organic compound on Earth. Propylene oxide is an organic compound with the chemical formula CH3CHCH2O. Methyl chloride is a colorless, flammable gas with a sweet odor.
The reaction of cellulose with propylene oxide and methyl chloride results in the formation of hydroxypropyl groups, which are attached to the cellulose molecules. This process is known as hydroxypropylation. The hydroxypropyl groups increase the solubility of the cellulose in water, making it easier to use in a variety of applications.
HPMC is widely used in the pharmaceutical industry as a binder, disintegrant, and suspending agent in tablets and capsules. It is also used as a thickener and emulsifier in creams and lotions, and as a film former in eye drops. In the food industry, it is used as a thickener, stabilizer, and emulsifier in sauces, dressings, and other food products. In the construction industry, it is used as a binder in cement and mortar, and as a water-resistant coating for walls and floors.
HPMC is a safe and non-toxic material that is approved by the US Food and Drug Administration (FDA) for use in food, pharmaceuticals, and cosmetics. It is also approved by the European Union (EU) for use in food and pharmaceuticals.