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Glycerine: Colorless, transparent, viscous liquid; odorless with a sweet taste. Density is 1.2613 g/cm3, and the melting point is 17.8°C. Boiling point 290°C (decomposition). Refractive index 1.4746. It mixes gently with water and alcohols in any proportion. Slightly soluble in ether and ethyl acetate; insoluble in benzene, chloroform, carbon tetrachloride, carbon disulfide, and gasoline. It can absorb moisture from the air, as well as hydrogen sulfide, hydrogen cyanide, and sulfur dioxide. It is neutral to litmus. When kept at a low temperature of 0°C for an extended period, glossy rhombohedral crystals with a melting point of 17.8°C can be formed. It can cause combustion and explosion in contact with strong oxidizers such as chromium trioxide, potassium chlorate, and potassium permanganate. Non-toxic. Uses: It is an important raw material in the organic chemical industry, with currently around 1,700 different applications. The chemical industry uses it to manufacture alkyd resins, epoxy resins, glycerin rosin resins, modified phenolic resins, anhydrous malic anhydride resins, polyether resins, polyurethane resins, and others. The pharmaceutical industry uses it to manufacture drugs such as glycerol borate and pepsin, and it is also used as a solvent, desiccant, antifreeze, sweetener, etc. The textile printing and dyeing industry uses them to manufacture agents for preventing wrinkles and shrinkage in fabrics, as well as dispersants, penetrants, and lubricants. It is used in the food industry as a sweetener and as a moisture absorber in tobacco. Main derivatives: 1. Epichlorohydrin. Molecular formula: CH2OCHCH2Cl; Molecular weight: 92.5249; CAS number: 106-89-8. Properties: A volatile, unstable colorless oily liquid with an odor similar to that of chloroform. Toxic. Mixes well with most organic solvents, slightly soluble in water. Density is 1.18066 g/cm3. Boiling point: 116.11°C. Freezing point: -57.2°C. Vapor pressure (20°C) 1.666 kPa. Viscosity (28°C) 1.03 mPa·s. Flash point (open cup) 40.6°C. Autoignition point 415.6°C. The upper limit of the flammability limit in air (volume %) is 21.0, and the lower limit is 3.8. Preparation method: First, glycerol is chlorinated to form dichloropropanol, which is then saponified to produce epichlorohydrin. Use: Raw material for organic synthesis, such as in the production of epoxy resins ； It is also used as a solvent, plasticizer, and surfactant. 2. Glycerin monostearate: Molecular formula: C21H42O4; Molecular weight: 358.56; CAS number: 123-94-4. Properties: A white to slightly yellow waxy solid. Molecular weight 358.56. Density is 0.97 g/cm3. Melting point 58-59°C. It is insoluble in water, but can be dispersed in water when vigorously shaken and mixed with hot water. Soluble in hot ethanol and vegetable oil. Preparation method: The esterification method is primarily used. It is obtained by carrying out an esterification reaction using stearic acid and glycerol as raw materials in the presence of sodium hydroxide as a catalyst, followed by purification. Use: It is one of the main ingredients in the manufacture of cream-based cosmetics, possessing excellent emulsifying properties that enable creams to be smooth, uniform, and stable. 3. Glyceryl triacetate: Molecular formula: C9H14O6; Molecular weight: 218.20; CAS number: 102-76-1. Properties: Colorless oily liquid. Melting point: 4.1°C, boiling point: 258–259°C at 130.5°C (0.39 kPa); relative density: 1.1596 (20/4°C); refractive index: 1.4301; flash point: 148.8°C. It is miscible with ethanol, ether, chloroform, and benzene, and slightly soluble in water and carbon disulfide. It tastes bitter. Preparation method: Obtained by the esterification of glycerol with acetic acid. After preheating glycerol to 50-60°C, acetic acid, benzene, and sulfuric acid are added. Heat, stir, and reflux for dehydration; after dehydration, recover benzene, then add acetic anhydride and heat for 4 hours. After cooling, the pH is adjusted to 7 using 5% sodium carbonate; the aqueous layer is separated, and the crude oil is dried with calcium chloride. Under reduced pressure distillation, the fraction collected at 128–131°C (0.93 kPa) is triacetin. Uses: Used as a fragrance fixative, solvent, and toughener. It is used in the production of cosmetics, pharmaceuticals, and dyes, as well as as a plasticizer in cigarette filters. 4. Trinitrin: Molecular formula: C3H5N3O9; Molecular weight: 227.09; CAS number: 55-63-0. 4 Properties: Also known as nitroglycerin. A colorless or pale yellow viscous liquid, with two crystal forms: the stable form, with a melting point of 13℃ ； Unstable form, melting point 2.8°C. It decomposes at 50–60°C. Density (25/4°C) is 1.5918 g/cm3; it is flammable and explosive, and can explode at 218°C. Stable crystals can be formed during condensation. Slightly soluble in water; miscible with ethanol, ether, acetone, benzene, glacial acetic acid, ***, etc. It decomposes in the presence of concentrated sulfuric acid, caustic soda, and sodium sulfide solutions. Preparation method: It can be obtained through an esterification reaction between glycerol and a mixed acid of concentrated nitric acid and concentrated sulfuric acid. Use: Mainly used as **, and also as a gelatinizing agent for nitrocellulose ； Its solution is a vasodilator for the coronary arteries and an emergency medication for treating angina pectoris. 5. Ally glycidyl ether: Molecular formula C6H10O2, molecular weight 114.2, CAS number 106-92-3. Properties: Colorless, transparent liquid with a distinctive odor ； Vapor pressure 0.37 kPa/20℃ ； Flash point 57℃ ； Melting point -100℃ ； Boiling point 154℃ ； Solubility: Soluble in water, soluble in acetone, benzene, carbon tetrachloride, alcohols ； Density: Relative density (water=1) 0.96 ； Relative density (air=1) 3.9 ； Stability: Stable ； Hazard symbol 7 (Flammable liquids). Primary uses: as a fiber modifier, a stabilizer for chlorinated organic compounds, and a reactive diluent and modifier for synthetic resins. 6. Glycidyl ether: Properties: A type of epoxy resin. Bisphenol A-type glycidyl ethers are the most important category. Preparation method: It is obtained through a polycondensation reaction of glycerol or polyphenols with epichlorohydrin. Use: 85% is used in the production of epoxy resins. It can also be used to produce linear phenol-formaldehyde varnish resins, tetrabromobisphenol A resins, glycerol-based resins, and pentaerythritol resins, among others. 7. Calcium glycerophosphate 1,2,3-Propanetriol, mono(dihydrogen phosphate), calcium salt ； Molecular formula: C3H7CaO6P CAS: 27214-00-2 Properties: White or slightly yellow powder. It is odorless and tasteless. Slightly hygroscopic in air. Slightly soluble in water, insoluble in ethanol, soluble in glycerin. Adding citric acid can increase its solubility in water, but it decomposes easily when heated. Preparation method: Glycerol is heated together with phosphoric acid to produce glycerophosphoric acid, which is then neutralized with lime milk, and precipitated using ethanol to obtain the final product. Use: It is a calcium fortifier for food, used in bread, flour, noodles, soy milk, etc. The usage is below 1%. 8. Glycerol formaldehyde Molecular formula: C4H8O3 Molecular weight: 104.11 CAS number: 86687-05-0 Property: Liquid. Boiling point: 191–195°C, 95–97°C (2.66 kPa); relative density (20/4°C): 1.215; refractive index (nD20): 1.451. Soluble in water, alcohol, chloroform. The pH of a 10% aqueous solution is 4–6.5. Preparation method: It is obtained by the reaction of glycerol and formaldehyde. Use: Pharmaceutical solvent, a substitute for glycerin and propylene glycol. It can be used in industries such as pharmaceutical manufacturing, non-aqueous injectables for animals (e.g., ivermectin, naproxen), solvents for injectable solutions (e.g., long-acting oxytetracycline, sulfonamides), cosmetics, insecticides, coatings, and high-quality inks, as well as in the casting industry. 9. Polyglycerin ； Glycerol homopolymer Molecular formula: (C3H8O3)n CAS number: 25618-55-7 Properties: Density 1.2892. Boiling point 290°C. Refractive index 1.4955. Flash point 156°C. Preparation method: It is synthesized through the direct polymerization of glycerol. Use: It is mainly used for synthesizing various polyglycerides, which are new types of emulsifiers that have been developed over the past thirty years. It has a very wide range of uses, and new applications are constantly being researched and developed. Its functions mainly include: emulsification, viscosity adjustment, control of crystallization, quality improvement, and antibacterial effects. 10. Rosin glyceride ； ester adhesive ； Properties of ester gum: Also known as ester adhesive. It should be completely transparent; the lighter its color, the better. The softening point is 55–65°C, and the acid value is less than 10. Preparation method: It is obtained by the esterification of rosin and glycerin. Uses: Compared to rosin, its acid value is significantly reduced; when used in the formulation of coatings, it reduces the brittleness and tackiness of the coating film, and also improves its weather resistance. But it is still not as good as cobalt resin or other synthetic resins. Due to its low cost and easy availability, it is widely used in the production of varnishes, enamel, etc. This post was last edited by zxh6267 on 2009-3-19 11:42.]