Physical and chemical properties
Pentaerythritol is also called 2, 2-double (hydroxymethyl)-1, 3-propanediol, four hydroxymethyl methane, MetabAuxil, Penetek. White crystal powder. It was first found in 1882 by Tollens, and is colorless tetragonal crystal double tetrahedral crystal precipitated from dilute hydrochloric acid. The relative molecular mass is 136.15. Relative density is 1.399. Melting point is 262 oC (industrial products containing 10%~15% Dipentaerythritol, melting point is 180~225 oC). The boiling point is 276 oC (4.00 x 103 pa). The refractive index is 1.54~1.56. Can sublimate. Slowly soluble in cold water, soluble in hot water, insoluble in carbon tetrachloride, ethyl ether, benzene, petroleum ether, ethanol, acetone, solubility at 25 oC (g/100 g) in water, methanol, ethanol, butylamine, dimethyl sulfoxide, ethanolamine are 0.75, 7.23, 0.33, 16, 16.5 4.5, respectively. 1 g of dipentaerythritol can soluble in 18 ml of water at 15 oC. Pentaerythritol will polymerize when heated to above melting point, and generates a shrinkage second shrinkage e four season three pentaerythritol, etc. Stability in the air. The hydroxyl groups of Pentaerythritol can form complex with many kinds of metal; Can directly react with nitric acid trough nitration; Under the effect of catalyst, the hydroxy can be oxidized to acid; Can react with chlorine to generate the chloride; In acid medium, the product react with carbonyl compounds, generate cyclic acetal and ketal; Like other alcohols, can esterify with an acid or anhydride to generate four ester; The halides can dehalogenate to generate cyclic ether in the role of alkali. The addition reaction intermediate of 3-hydroxy aldehyde can react with formaldehyde through Cannizzaro reaction to generate season four amyl alcohol and formic acid. In 1938, it was first generated by United States with acetaldehyde and five times the amount of formaldehyde in the reaction of calcium hydroxide solution system. It is the only production method used in the industrial. Main purpose is to make explosives and synthetic resin (mainly used for various coatings).
The main purpose and effect
As quaternary alcohol, pentaerythritol is easily generated by esterification acid and ester, so most of the classes used in alkyd resin coatings raw materials, mainly used for architectural coatings and automotive primer. Pentaerythritol is used to esterification with nitric acid to generate pentaerythritol tetranitrate (also known as PETN) in 5~15 oC in industrial, which is a kind of high explosives and bigger than TNT explosive, most as a booster, or mix with TNT. A lot of PETN have been used in the second world war. PETN has the effect of diastolic blood vessels, is a long-term vasodilator and can treat angina pectoris. Pentaerythritol reaction with rosin acid can produce rosin pentaerythritol ester, which can be mixed with drying oil and is a kind of coating with better hardness, water resistance and weather resistance, can be used in ink of varnish, floor, etc. By esterification condensation pentaerythritol or glycerol with phthalic anhydride, fatty acid can make an alkyd resin coating. Use of different kinds and different amount of fatty acid can improve the properties of alkyd resin, making it a suitable coating of various kinds in need. It is widely used as a coating on the surface of the metal, wood, as a bridge, railway, derrick, building and other aspects of commonly used industrial paint and architectural paint. Because of the price is low, alkyd resin of reactants, easy modification, strong adaptability, good comprehensive, it has become the backbone of the coating industry since 1927.
Pentaerythritol is often used in coating industry, is of alkyd coating raw material for the production of highly cross linked coatin using four hydroxyls, the coating has good hardness and color, can improve the hardness, luster and durability of the coating film. Used as varnish, paint and ink production of rosin ester raw material, and can be used as flame retardants, drying oil, aviation lubricating oil. Pentaerythritol fatty acid ester is polyvinyl chloride (PVC), plasticizer and stabilizer is also used in medicine, pesticide, lube oil manufacture.
Pentaerythritol acrylic ester generated by Pentaerythritol and acrylic acid has a fast drying property, it is widely used in radiation-curing coatings and quick drying of printing ink, water soluble alkyd resin, the polymer can be used as adhesive. The C6~C10 fatty acid ester of Pentaerythritol are mainly used as advanced lubricant for steam turbine, automobile engine etc. The ester produced by this product with C10~C12 fatty acid, can be used as a plastic plasticizer, which has low volatility and high ageing resistance; Reaction with epoxy compound, and its product can be used as a surface active agent, widely used in detergent and cosmetics and perfume raw materials; This product is used as the material of explosives, medicine, pesticides, organic intermediates, etc.
The above information is edited by the Chemicalbook of Duan Yalan.
Chemical additives
Pentaerythritol can be used as a stabilizing agent, and has synergistic effect with zinc salt stabilizers, can replace allyl chloride to stabilize PVC. General dosage is half serving. But the compatibility with the resin of this product is small, easy to bloom, and soluble in water, easy sublimation, easy deposit on processing equipment and interfere with the processing in the process of sublimation.
Harmful effects and symptoms of poisoning
Pentaerythritol has low toxicity, from rat infected through the mouth to the dose of 40 g/kg body weight, no obvious toxic symptoms. The US Food and Drug Administration permits it for food packaging materials (FDA121.2566), the highest dosage is 0.4%.
Someone reports and food studies showed that 85% of pentaerythritol were discharged from the urine after oral within 30 h. Generally speaking, according to the usual route of exposure even under abnormal use concentration, no significant effect to health.
Uses
It is mainly used in alkyd resin production, also used for manufacturing ink, lubricants, plasticizer, surface active agent, explosives and drugs raw materials.
Used as a resin and synthetic fiber antistatic agent, solvent conditioner, oil, etc.
Pentaerythritol is mainly used in the coating industry, is the source of alkyd resin coating, can make the coating film hardness, gloss, with improved durability, it is used as varnish, color paint and printing ink of pine resin needed raw materials, and with smoldering sex coating, drying oil and matter could be empty lubricating oil and so on. Pentaerythritol tetranitrate is a kind of high explosives (taian); The fatty acid ester is an efficient lubricant and PVC plasticizer; The epoxide production is the raw material from the raw surface active agent, pentaerythritol easy forms authority complex with metal, also as hard water softener used in detergent formulation, in addition, it can also be used in medicine, pesticide and other production.
Gas chromatographic stationary liquid [highest use temperature 150 ℃, the solvent of chloroform + butyl alcohol (1:1)], separation and analysis of low boiling point oxygen-containing compounds, amine compounds, nitrogen or oxygen heterocyclic compounds. Organic synthesis, preparation, resin synthesized polyols.
Production method
It is produced using formaldehyde and acetaldehyde as raw materials, in the presence of alkaline condensation agent reaction. When using sodium hydroxide as condensing agent, it is called sodium method. The molar ratio of raw materials for acetaldehyde: formaldehyde: alkali is 1.5: 6: 1.1-1.3. Adding sodium hydroxide solution to 37% formaldehyde solution, join the acetaldehyde under stirring at 25-32 oC and react for 6 to 7 h. By the neutralization filter to obtain pentaerythritol. Raw material consumption quota: formaldehyde (37%) 2880 kg/t, acetaldehyde 350 kg/t. When using calcium hydroxide as a condensing agent, it is called calcium method. The molar ratio of raw materials for acetaldehyde: formaldehyde: lime is 1: 4.7: 0.7-0.8. Add the formaldehyde solution, 20% acetaldehyde solution and 25% lime milk to reaction pot, react at 60 oC, condensate until liquid color turned to blue from gray. Gradually cooled to 45 oC in the acidification of pan. Acidificate the condensed liquid with 60-70% of the sulfuric acid to the pH of 2-2.5, then use filter airland to calcium sulfate. Filtrate through ion exchange column to remove residual calcium ion, stress concentration, keep gas temperature under 70 oC, vacuum at 77.3 kPa. Began to crystallize, transfer concentrate in the crystallizer, mixing the cooling crystallization, centrifugal separation, washed with water to the pH of 3, drying by the airflow then obtain products. The consumption of Calcium method is high, and also has the problem of "three wastes". Raw material consumption quota: formaldehyde (36.5%) 4700 kg/t, acetaldehyde 550 kg/t.
Category
Flammable fluid.
Toxicity grading
Poisoning
Acute toxicity
Oral-LD50 in rats: 12600 mg/kg. Oral LD50 in mice: 4097 mg/kg.
Stimulus data
Skin-rabbit 500 mg/24 hours light; Eyes-rabbit 126 mg light.
Flammability hazard characteristics
Flammable. Combustion produces stimulation of smoke.
Storage Characteristics
Warehouse ventilation, dry at low temperature.
Extinguishing agent
Dry powder, foam, sandy soil, and water.
Occupational standards
The TLV-TWA 10 mg/cubic meter.
Chemical Properties
Pentaerythritol is a white crystalline solid.
Odorless.
Uses
Pentaerythritol is a versatile starting material to synthesize various dendrimers and star-shaped polymers. It is widely used in the preparation of flame-retardant epoxy resins and polymer composites. It is also used in the synthesis of the vasodilator, pentaerythritol tetranitrate (PETN).
Uses
Pentaerythritol is a compound most commonly used in cosmetics (in its rosinate form). It is used as a skin conditioning agent (used as part of a cream base in lotions), and is also used to increase viscosity of cosmetic formulations.
Uses
In the manufacture of pentaerythritol
tetranitrate; alkyd resins in surface-coating compositions;
pentaerythritol triacrylate and protective
coatings; insecticides; pharmaceuticals
Definition
pentaerythritol: white crystallinecompound, C(CH
2OH)
4; m.p.260°C; b.p. 276°C (30 mmHg). It isused in making the explosive pentaerythritoltrinitrate and in producingresins and other organicproducts.
General Description
Odorless white solid. Sinks and mixes slowly with water.
Air & Water Reactions
Water soluble.
Reactivity Profile
Pentaerythritol is an alcohol. Pentaerythritol is incompatible with the following: Organic acids, oxidizers [Note: Explosive compound is formed when a mixture of PE & thiophosphoryl chloride is heated.] .
Reactivity Profile
The four primary hydroxyl groups undergo the normal reactions of OH groups. Pentaerythritol is oxidized to tris (hydroxymethyl)acetic acid by air in the presence of platinum or palladium.
Health Hazard
Non-toxic; no symptoms likely
Flammability and Explosibility
Not classified
Safety Profile
Mildly toxic by ingestion. A nuisance dust. Flammable from heat or flame or oxidizers. Wxtures with thiophosphoryl chloride react when heated to form a product that ignites and then explodes on contact with air. Used in coatings, stabdizers, explosives, P.E.T.N resins, drugs, insecticides, and lubricants When heated to decomposition it emits acrid smoke and irritating fumes
Potential Exposure
Pentaerythritol is used in coatings and
stabilizers; in the formation of alkyd resins and varnishes.
It is used as an intermediate in the manufacture of plasticizers,
explosives (PETN),and pharmaceuticals.
Shipping
UN1987 Alcohols, n.o.s., Hazard Class: 3;
Labels: 3-Flammable liquid.
Purification Methods
Reflux pentaerythritol with an equal volume of MeOH, then cool, and the precipitate is collected and dried at 90o. It can also be crystallised from dilute aqueous HCl. After sublimation under high vacuum at 200o it has m 265.5o. Its solubility in H2O is 10%. [Beilstein 18 III 2361, 1 IV 2812.]
Incompatibilities
Dust may form explosive mixture with
air. Incompatible with oxidizers (chlorates, nitrates, peroxides,
permanganates, perchlorates, chlorine, bromine, fluorine,
etc.); contact may cause fires or explosions. Keep
away from alkaline materials, strong acids, organic acids,
strong bases. Aquesous solution is acidic. Explosive
compound is formed when a mixture of Pentaerythritol and
thiophosphoryl chloride (CAS 3892-91-0) is heated.
