Properties and Preparation of Isosorbide
Isosorbide is a dehydrated derivative of sorbitol, an oral osmotic dehydration diuretic, and its mechanism of action is similar to that of intravenous mannitol and sorbitol. By increasing plasma osmotic pressure, water in tissues (including eyes, brain, cerebrospinal fluid, etc.) enters blood vessels, thereby reducing tissue edema, reducing intraocular pressure, intracranial pressure, and cerebrospinal fluid volume and pressure. Note that isosorbide is used in the treatment of cerebral edema and glaucoma. The application of isosorbide as a secondary dehydration derivative of sorbitol is a new type of bio-based material and a widely used Chemical Intermediate. Isosorbide has remarkable medicinal value and is widely used in medicine, food, chemical industry, feed additive and other industries. The application of isosorbide in polymer modification and polymer degradation has begun, further expanding the application field of isosorbide. As a secondary dehydration derivative of sorbitol, isosorbide is a new type of bio-based material and a widely used chemical intermediate. Isosorbide has remarkable medicinal value and is widely used in medicine, food, chemical industry, feed additive and other industries. The application of isosorbide in polymer modification and polymer degradation has begun, further expanding the application field of isosorbide. Isosorbide properties: Isosorbide is a green, non-toxic, rigid monomer with excellent properties such as chirality. Preparation of isosorbide nitrate, commonly used in heart or cardiovascular diseases; preparation of alkyl derivatives; use as solvent in pharmaceutical or cosmetic compositions; synthesis of liquid crystal materials; synthesis and modification of polymers. Because of its chirality and inherent rigidity, isohexitol has been the subject of intensive research in various application fields, from catalysis to pharmaceuticals, liquid crystalline materials, and synthetic polymers. Incorporating these rigid diols into polyesters increases the glass transition temperature (Tg). Utilizing the chiral characteristics of isosorbide, color-changing coatings can be prepared, and have excellent UV resistance, acid and alkali resistance, heat resistance and weather resistance, and can be applied to the surface coating of various materials.
Preparation Process: Isosorbide can be obtained by catalyzed dehydration of sorbitol. Sorbitol can be converted from renewable resources such as starch, sucrose, and glucose. It has already been industrially produced on a large scale, with mature technology and low price. The traditional preparation method of isosorbide mostly adopts the catalytic method of acid catalyst. In these methods, commonly used catalysts are: liquid acid (as sulfuric acid, phosphoric acid etc.), solid acid (metal salt and modified metal oxide and heteropolyacid etc.) and acidic ion exchange resin etc. The production of isosorbide by liquid acid catalysis has large pollution, serious equipment corrosion and difficult product separation. Using solid sorbitol as raw material and solid acidic molecular sieve as catalyst; the mass ratio of solid sorbitol and molecular sieve is 100︰1.0~5.0, and the catalytic reaction is 2~ After 6 hours, isosorbide was obtained. After the reaction is completed, the content of isosorbide in the product is more than 80%. The method for preparing isosorbide of the present invention has less catalyst consumption, recyclable and reusable catalyst, good reaction selectivity, high yield and simple aftertreatment.
Isosorbide can be obtained by catalyzed dehydration of sorbitol. Sorbitol can be converted from renewable resources such as starch, sucrose, and glucose. It has already been industrially produced on a large scale, with mature technology and low price.
