POLYPROPYLENE GLYCOL 400

The term "oxide" is used for a high molar mass polymer when the end groups no longer affect the polymer properties. PPG 400 is used in many formulations for polyurethanes. It is used as a rheology modifier. PPG 400 is used as a surfactant, wetting agent, dispersant in leather coating. PPG is also used as a gauge reference and calibrant in mass spectrometry. PPG, paintball yapımında ana bileşen olarak kullanılır. PPG, bazı müshillerin yapımında birincil bileşen olarak kullanılır.

A polypropylene glycol, 400 molecular weight homopolymer diol initiated with propylene glycol. It is a multipurpose short diol that can be blended with other polyols for the production of two-component compact or foam systems and with one-component prepolymer-based products for coatings, adhesives and sealants with a variety of end uses such as elastomers, adhesives, coatings. Polyglycol P-400E is a linear polymer produced by controlled, catalyzed reaction between propylene oxide and water. PPG P-400E, as this product is also known, is a clear, viscous liquid at room temperature. It has a low pour point and, unlike the higher molecular weight PPGs, is completely soluble in water at 25 °C. It loses its water solubility at higher temperatures. 

Like all polypropylene glycols, Polyglycol P-400E is soluble in all proportions with any organic solids and liquids, the main exception being long chain aliphatic hydrocarbons. Polyglycol P-400E possesses excellent lubricity and has a low vapor pressure. Under extreme heating conditions it does not form coke nor does it form a varnish. Decomposition products are low boiling products that are either lost as volatiles or soluble in the polypropylene glycol. As PPG P-400E is water-soluble it is used in areas not usually associated with the higher molecular weight PPGs. For example it is used as a dust adhesive fluid, as solvent/coupler for inks and pesticide formulations. Besides the other outlets given above PPG P-400E is also used to make resins, fatty acid esters, lubricants, metal working fluids and as plasticiser.

Polypropylene glycols are relatively easy to store and handle. They can be stored in bulk in steel tanks, which should be padded with nitrogen or any other inert gas to prevent air from entering the tank. If slight iron pickup and color changes cannot be tolerated then the storage tanks should be constructed from stainless steel. To ease the handling of polypropylene glycols somewhat, higher storage temperatures should be considered to keep the viscosity of the polyglycols within limits suitable for the pumping equipment available. The maximum storage temperature should not exceed 40°C to avoid the risk of product degradation. Pipelines may also require insulation and/or tracing to maintain suitable product temperatures. Although PPGs have very low pour points, especially polyglycols P-2000E and P-4000E become very viscous at low temperatures. Consequently it is recommend that they be stored in tanks which are well insulated and heated. Externally located heating devices are preferable to internally sited ones. With external heating the risk of accelerating product deterioration is greatly reduced. Similarly drums should be stored under cover, or preferably inside a warehouse, to maintain the temperature of the polyglycol at a level which allows for easy discharge. The shelf life of properly stored bulk and unopened drums is, at least, 24 months. Propylene glycol can be used as raw material for unsaturated polyester resin. In cosmetics, toothpaste and soap can be used with glycerol or sorbitol with a wetting agent. Used in hair dyes humidity, uniform hair agent, also used as an antifreeze, is also used cellophane, plasticizers and pharmaceutical industries.

Propylene glycol is a colorless and virtually odorless viscous liquid. It does not irritate the skin, but is mildly irritating to the eyes. Propylene glycol has a slightly sweet taste and is approved by the U.S. Food and Drug Administration for certain uses as food additives. Propylene glycol is hygroscopic and very stable. It has a high boiling point and low vapor pressure. Also, propylene glycol has the ability to dissolve other substances and is completely water-soluble.

The properties of propylene glycol make it perfect for a lot of specific uses in many different industries. Propylene glycol has a very broad array of practical applications and is used as a chemical ingredient in many products including anti-freezes, foods, cosmetics products, pharmaceuticals, aircraft de-icing fluids, fragrances, and personal care products.

These are some of the ways propylene glycol is used:

• As a solvent in pharmaceuticals including oral, inject-able, and topical formulas.
• As a moisturizer in medicines, cosmetics, food, toothpaste, shampoo, conditioner, pet care products, mouth wash, hair dye, and tobacco products.
• As an ingredient in massage oils, fragrance oils, hand sanitizers, antibacterial lotions, and saline solutions.
• To make artificial smoke or fog theatrical productions and firefighter training.
• As a vaporizable base for diluting the nicotine liquid in electronic cigarettes.
• As a solvent for food colors and food flavorings.
• As a wetting agent to determine time needed for paints and coatings to dry.
• As a lubricant in air conditioning compressors.

PEG 400 (polyethylene glycol 400) is a low-molecular-weight grade of polyethylene glycol. It is a clear, colorless, viscous liquid. Due in part to its low toxicity, PEG 400 is widely used in a variety of pharmaceutical formulations. PEG 400 is strongly hydrophilic. PEG 400 is soluble in water, acetone, alcohols, benzene, glycerin, glycols, and aromatic hydrocarbons, and is slightly soluble in aliphatic hydrocarbons. Polyethylene glycol 400 (PEG400) is a commonly used co-solvent.

PEG 400 is a clean, simple, somewhat viscous, colourless and odourless liquid polyethylene glycol. Many PEGs are possible with varying chain lengths from tens to hundreds or even thousands of repeating ethylene oxide links in their chains. PEG 400 is one of the shorter polymers having a nominal average molecular weight, Mn, of 400, which corresponds to a chain length of about 8-9 links. It is highly valued in pharmaceutical applications due to its low toxicity and its exceptional ability to solubilise polar APIs (Active Pharmaceutical Ingredients).

PEG 400 is generally considered stable, non-reactive, soluble in all proportions with water and also soluble in acetone, alcohols, benzene, glycerine, glycols and aromatic hydrocarbons. This versatile excipient has found application in topical, ophthalmic, oral and parenteral dosage forms. It is recognised worldwide as an effective solvent or API ‘vehicle’ and has monographs in the major national Pharmacopoeias. While generally considered stable all PEGs are somewhat susceptible to oxidative degradation. Peroxides, when present, can be catalytic in PEG degradation ultimately causing loss of viscosity and increasing acidity over time. These degradation pathways also exist in the absence of oxygen if the peroxide and other impurities pre-exist in the excipient prior to drug formulation. PEG degradation and impurities can adversely affect the drug stability. Presence of peroxide, aldehyde, residual reactants, moisture and trace acids can all lead to adverse effects. Most pharmaceutical grade PEGs 400 easily meet monograph specifications but can still contain sufficient trace impurities that drug formulations may experience early drug product degradation in dosage forms where PEG 400 is used.  It is the ability of PEGs to form complexes with active substances that is responsible for their excellent solvent power.

However, equilibrium constants for complex formation vary considerably from one substance to another, and certain drugs such as Penicillin G and Bacitracin can even become inactivated. The effect of the polyethylene glycol on the efficacy and absorbtion of a drug must therefore always be determined in tests. The product is mainly applied as solvent for oral and topical preparations. PEG-400 has been used as a green and biodegradable polymeric solvent for the one-pot, two-step, multi-component synthesis of novel asymmetrical bis-spirooxindole derivatives by the reaction of N-alkyl isatin, isatin derivatives, alkylmalonates and C–H activated carbonyl compounds in the presence of K2CO3 at room temperature. Using this procedure, all the products were obtained in good to excellent yields.