Acid esters of polyols

Chem. Descrip. Fatly acid ester of polyol Uses Internal lubricant for rigid PVC for use in inj. molding, extmsion, and calendering food-contact coatings, paper, cellophane, textiles Regulatory FDA 21CFR 175.300, 176.170, 176.180, 177.1200,... 

Loxiol HOB 7111 [Cognis KGa/VPIastics Tech. Cognis/Chems. Group] Chem. Deserp. Fatty acid ester of polyol... 

Shell Oil Co. EB/UV radiation cure of composition comprising a monoalkenyl arene/conjugated diene block copolymer, tackifying resin, and a di-tetra functional acrylate or methacrylate selected from the group consisting of acrylic and methacrylic acid esters of polyols. Improved high-temperature properties and solvent resistance. PSA properties,... 

These are the classic lubricants, derived from natural oils and fats and acting by migrating to the surface. A wide range of fatty acid esters of polyols and other compounds is used as internal lubricants, especially in PVC. Good flow, surface finish and improved clarity can be achieved in most processes, using either compounded or dry blend formulations. According to type, they can improve mould release, melt flow, lubricity, and scratch/scuff resistance and reduce static build-up and wear. 

Description Fatty acid esters of polyol, fatty alcohol ... 

Chem. Descrip. Fatty acid ester of polyol... 

Sorbitol is the most important higher polyol used in direct esterification of fatty acids. Esters of sorbitans and sorbitans modified with ethylene oxide are extensively used as surface-active agents. Interesteritication of fatty acid methyl esters with sucrose yields biodegradable detergents, and with starch yields thermoplastic polymers (36). 

Methyl esters of soya, rapeseed and palm oil fatty acids used as biodiesel (Chapters 7 and 8) are preferentially manufactured by transesterification." The acid catalyzed esterification and the alcoholysis of triacylglycerides apply also for the manufacture of higher alcohol monoesters as well as for fatty acid polyol esters. Due to their oily consistency and to their solubilizing properties fatty acid esters of low Mw alcohols are components in odorous substances like perfumes, and cosmetic and drug formulations such as ointments, creams or lotions. 

The fatty acid esters of C5 polyols such as (H3C)2C(CH20H)2, H3CC(CH20H)3 and C(CH20H)4 contain only acylated primary alcohol functions. Such compounds are more stable than glycerides to oxidation, hydrolysis and thermal decomposition. Usually acylated with Ce-Cio acids, they have low solidification points (—50 °C or below) and, because of their low viscosities over a wide temperature range, they are important constituents of high-temperature lubricants. 

Esters of polyols (polyalcohols) and higher fatty acids frequently are used as non-ionic emulsifying agents. The sorbitan esters of fatty acids eure well known. They are prepared by esterification of sorbitol with fatty acids at temperatures of at least 190°C, usually at 220-240°C. During the reaction, a substantial portion of the sorbitol (more them 75%)is converted into anhydro-compounds (intramolecular ethers like sorbitan and isosorbide). The products become less hydrophilic due to the foirmation of these anhydro-compounds. 

EMSORB Sorbitan Fatty Acid Esters, or polyol esters, are created by the two basic mechanisms of dehydration and esterification. Sorbitol, with six hydroxyl groups, is dehydrated, undergoing ring closure with the loss of two hydroxyl groups. The cyclic sorbitan moiety is produced. Through the esterification reaction, hydrophobic fatty acids are combined with the sorbitan, thereby decreasing its hydrophilic attributes. The exact degree of hydrophllicity depends on the size and number (mono-, di-, tri-) of acid molecules added to one sorbitan molecule. 

The esterification methods used for the sugars (Chapter III) are applicable to the polyols. The preparation and properties of organic and inorganic esters of polyol anhydrides are considered in Chapter VII. Fully esterified derivatives are generally unobtainable by direct esterification with organic acids because internal anhydrides are formed. Partial esters, especially diesters, may be obtained by the use of amounts of benzoyl or p-toluenesulfonyl chlorides insufficient for complete esterification (93),... 

When mixed esters of polyols are prepared using, in part, a dibasic acid, the product is an ester lubricant that is a low polymer. This leads to a high order of resistance to extraction, bloom, or deposition. Pentaerythritol adipate-stearate is used in clear rigid PVC compounds as an efficient multifunctional lubricant, despite its relatively high cost. The corresponding adipate-oleate, a liquid, is more generally used in plasticized compounds in conjunction with mixed metal stabilizers, particularly if the latter are relatively nonlubricating. 

Polyol ester turbine oils currendy achieve greater than 10,000 hours of no-drain service in commercial jet aircraft with sump temperatures ranging to over 185°C. Polyol esters are made by reacting a polyhydric alcohol such as neopentyl glycol, trimethylol propane, or pentaerythritol with a monobasic acid. The prominent esters for automotive appfications are diesters of adipic and a2elaic acids, and polyol esters of trimethylolpropane and pentaerythritol (34). 

Carboxylic Acid Esters. In the carboxyflc acid ester series of surfactants, the hydrophobe, a naturally occurring fatty acid, is solubilized with the hydroxyl groups of polyols or the ether and terminal hydroxyl groups of ethylene oxide chains. 

Various polymers, such as polythiourethanes, polythioethers, and polythioacrylates, are used to produce resins which are transparent, colorless and have a high refractive index and good mechanical properties, useful for the production of optical lenses. Higher refractive indices are promoted by sulfur compounds and especially by esters of mercaptocarboxyhc acids and polyols such as pentaerythritol (41) (see Polymers containing sulfur). 

Fuels, Lubricants, and Transmission Fluids. Polyol esters of neopentanoic acid have been used as high vacuum pumping hquids that are stable in chemically aggressive environments (70). Esters such as 6- -ani1inophenoxy)hexy1 pivalate are used as antioxidants for synthetic ester lubricants (71). PivaUc anhydride [1538-75-6] has been claimed as an antiknock additive for gasoline (72). 

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