Properties, application and production process of 6000 polyethylene glycol 4000 factory

Physicochemical properties

According to the relative molecular weight, the physical form of polyethylene glycol can be from white mucus mw200-700 to waxy semisolid (mw1000-2000) to hard waxy solid (mw3000-20000). Polyethylene glycol is soluble in water and some common organic solvents. Liquid polyethylene glycol can be miscible with water in any proportion, while solid polyethylene glycol has only limited solubility. However, the solubility of polyethylene glycol in water is still more than 50% even if it is of relative molecular weight. If the temperature is high enough (such as PEG-6000, 60 ℃), the solid polyethylene glycol of all fractions can be dissolved in any proportion with water. However, when the temperature continues to rise close to the boiling point of water, even in a dilute solution, polyethylene glycol will precipitate, and the precipitation temperature depends on the relative molecular weight and concentration of the polymer. When polyethylene glycol is mixed with water, there is a slight volume shrinkage and significant exothermic.

In general, polyethylene glycol is stable, but it can react with oxygen in the air at 120 ℃ or higher. In an inert atmosphere (such as nitrogen and carbon dioxide), even when heated to 200-240 ℃, it will not change. When the temperature rises to 300 ℃, it will undergo thermal cracking. Adding antioxidant, such as phenothiazine with mass fraction of 0.25% ~ 0.5%, can improve its chemical stability.

 Any of its decomposition products are volatile and do not form hard shell or slimy deposits.

Polyethylene glycol is a kind of high molecular polymer condensed from ethylene oxide and water, which is non-toxic and non irritant. Its molecular formula is h (och2) Noh. It is widely used in various pharmaceutical preparations. There are a series of products according to the degree of polymerization. When the molecular weight of PEG is less than 1000, it is liquid; when it is more than 1000, it is solid. PEG 6000 and PEG 4000 are the most commonly used matrix of dropping pills.

Polyethylene glycol 6000 and polyethylene glycol 4000 are easily soluble in water, ethanol, acetone, chloroform, etc., and insoluble in petroleum ether, ether, glycol, dimethylsilicone oil, liquid paraffin, vegetable oil, etc. Polyethylene glycol 6000 and polyethylene glycol 4000 are white waxy solid and tasteless. Their melting points are 55-60 ℃ and 48-53 ℃, respectively. The relative density is 1.072-1.075 at 100 ℃, the pH value of the solution is 4.0-7.0, and the dielectric constant is 3.6. Polyethylene glycol 6000 and polyethylene glycol 4000 have no physiological functions in themselves. They have good chemical stability, no hydrolysis, heat resistance and no corrosion. They can adsorb some liquids. They are helpful for the dissolution of drugs and slightly wetting. After contacting with water, they first expand into gel and then dissolve.

Polyethylene glycol (PEG) can be dissolved in other molten drop matrix, such as polyoxyethylene monostearate (S-40), polyvinylpyrrolidone (PVP), poloxamer, stearic acid, glycerin monostearate, etc. Therefore, it can be made into composite matrix, and can also be added with disintegrant, solubilizer, etc. to improve its properties. The hardness and heat resistance of PEG6000 are better than that of PEG4000. Generally, traditional Chinese medicine dropping pills contain extract and volatile oil, which can reduce the hardness of dropping pills. Therefore, traditional Chinese medicine dropping pills usually use it as the matrix.

Some drop pills often use different proportion of polyethylene glycol 6000 and polyethylene glycol 4000 mixed matrix, for example, when polyethylene glycol 4000 is used as the matrix, adding part of polyethylene glycol 6000 can improve the hardness, fluidity and heat resistance of drop pills; when polyethylene glycol 6000 is used as the matrix, adding part of polyethylene glycol 4000 can reduce the viscosity and dropping temperature of drug solution, and avoid the roundness of drop pills Poor, drag needle tail and other phenomena. However, it was found that when the ratio of PEG 6000 to PEG 4000 was 1:1, the heat resistance of PEG 6000 was the worst, which was not conducive to drug transportation and storage.

Solubility

Polyethylene glycol is soluble in most high polar organic solvents, such as alcohols, alcohol silicon mixtures, diols, esters, ketones, aromatic hydrocarbons, nitroalkanes, etc. It is insoluble in aliphatic hydrocarbons, cycloalkanes and other organic solvents with low polarity. The solubility of PEG is related to its molecular weight and temperature. In addition, peg is also soluble in monomers of low-grade aldehydes, amines, organic acids, anhydrides and polymers. But it is not soluble in rapeseed oil, mineral oil and other compounds with long hydrocarbon chain.

Liquid polyethylene glycol (such as PEG-400) has good solubility for many pharmaceutical raw materials, which is very useful in application.

purpose

Polyethylene glycol and polyethylene glycol fatty acid ester are widely used in cosmetics industry and pharmaceutical industry. Because polyethylene glycol has many excellent properties: water solubility, non volatility, physiological inertia, mildness, lubricity and make the skin moist, soft and pleasant after use. The viscosity, hygroscopicity and structure of the products can be changed by selecting different molecular weight fractions of PEG. Polyethylene glycol (Mr<2000) with relatively low molecular weight is suitable for wetting agents and consistency regulators. It is used in cream, lotion, toothpaste and shaving cream. It also applies to hair products that are not washed, giving hair a filamentous luster. High molecular weight polyethylene glycol (Mr >2000) is suitable for lipstick, deodorant stick, soap, shaving soap, foundation and cosmetics. In cleaning agent, polyethylene glycol is also used as suspending agent and thickener. In the pharmaceutical industry, it is used as the base of ointment, emulsion, ointment, lotion and suppository. Polyethylene glycol (such as polyethylene glycol NF, Dow Chemical Co.) is more suitable for cosmetics. The application of methoxy polyethylene glycol and polypropylene glycol is similar to that of polyethylene glycol.

Safety

US Federal Food and drug