Alkyd resins polyol component

The typical alkyd resin (see above) is eomprised of three basic components an aromatic diacid such as phthalic anhydride which together with a polyol such as glycerol, forms the backbone of the resin molecule and along which are distributed the fatty acids derived from vegetable oils. The solubility, film hardness and colour of alkyd resins depend on the nature of the modifying fatty acid which in most cases contributes some colour to the film. 

The main reactions involved in alkyd resin synthesis are polycondensation by esterification and ester interchange. If one uses the following symbols to represent the basic components of an alkyd resin o-R—o, a polyol molecule or radical ... 

Each of the three principal components of alkyd resins—the polybasic acids, the polyols, and the monobasic acids— has a large variety to be chosen from. The selection of each one of these ingredients will affect the properties of the resin. As will be shown later, the choice of ingredients may even affect the choice of manufacturing processes. To both the resin manufacturers and the users, the selection of the proper ingredients is a major decision. 

The following compounds are most commonly used for the polyol component of alkyd resins glycerol, ethylene glycol, penta-erythrltol, propylene glycol, dipentaerythritol, neopentyl glycol, sorbitol, diethylene glycol, trimethylolethane, dipropylene glycol, trimethylolpropane, and cyclohexanedimethanol. The structures of... 

Hazardous Decomp. Prods. Heated to decomp., emits acrid smoke and irritating fumes NFPA Health 0, Flammability 1, Reactivity 0 Storage Hygroscopic Uses Intermediate in emulsifiers, resins, plasticizers, pharmaceuticals, insecticides, dyestuffs, mold lubricants brake/hydraulic fluid component comonomer for alkyd resins and unsat. polyester resins chain extender for PU thickener in cosmetics solvent, homogenizer for inks, other coloring materials initiator for urethane polyols in varnish removers, hard surf, cleaners, penetrating oils lubricant, antifreeze for carburetor fluids cooling media disinfectant in foods, soaps, personal care... 

TTiere are two processes for making alkyd resins, the fatty acid process, in which the three components are heated together at around 200 C, and the monoglyceride process in which the oil and polyol are first heated together to form partial glycerides, which are then reacted with the polycarboxylic acid or its anhydride. In the latter case the glycerol of the oil forms part of the total polyol component. 

The detection and identification of polar components is also possible using simultaneous hydrolysis and alkylation. These are normally difficult or impossible to determine because they tend to remain on the column, cause peak tailing, show poor reproducibility, or lose their identity due to the formation of low molecular weight fragments. Thus, for example, methyl esters of polybasic acids and long-chain fatty acids and methyl ethers of polyhydric alcohols are formed from alkyd resins with TMAH, whereas in conventional PyGC, aldehydes are formed from polyols, and alkanes and alkenes from fatty acids (Figure 6). 

A substantial number of studies on the characterization of vehicle paints, mainly alkyd and acrylic resins, have been reported. Alkyd resins, which are complex polyesters formed by co-polymerizing phthalic anhydride, polyols, and saturated and rm-saturated fatty acids, can usually be classified with MS techniques on the basis of hydrocarbon chain length and modification components such as melamine. Characterizations of acrylic resins are based on Cl MS analysis of monomers that are reasonably reproducible by pyrolysis techniques. 

Two of the three binder systems used by the foundry industry are two-component, room-temperature curing adhesives. All systems use polymeric MDI as the isocyanate component. All of the cross-linkable components are polyols. The first polyol introduced into the industry was an alkyd oil resin consisting of linseed oil, pentaerythritol and isophthalic acid. The system... 

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