Product Code Database
In organic chemistry, a polyol is an organic compound containing multiple (). The term "polyol" can have slightly different meanings depending on whether it is used in food science or polymer chemistry. Polyols containing two, three and four hydroxyl groups are , , and tetrols, respectively.
Polyester polyols can be used to produce rigid foam. They are available in both aromatic and aliphatic versions. They are also available in mixed aliphatic-aromatic versions often made from recycled raw materials, typically polyethylene terephthalate (PET).
Acrylic polyols are generally used in higher performance applications where stability to ultraviolet light is required and also lower VOC coatings. Other uses include direct to metal coatings. As they are used where good UV resistance is required, such as automotive coatings, the isocyanate component also tends to be UV resistant and hence isocyanate oligomers or based on Isophorone diisocyanate are generally used.
Caprolactone-based polyols produce polyurethanes with enhanced hydrolysis resistance.
Polycarbonate polyols are more expensive than other polyols and are thus used in more demanding applications. They have been used to make an isophorone diisocyanate based prepolymer which is then used in glass coatings. They may be used in reactive hotmelt .
All polyols may be used to produce polyurethane . These then find use in coatings, adhesives, sealants and elastomers.
| Low molecular weight polyols |
Pentaerythritol |
Xylitol |
Sugar alcohols are added to foods because of their lower caloric content than ; however, they are also, in general, less sweet, and are often combined with high-intensity Sugar substitute. They are also added to chewing gum because they are not broken down by bacteria in the mouth or metabolized to acids, and thus do not contribute to tooth decay. Maltitol, sorbitol, xylitol, erythritol, and isomalt are common sugar alcohols.
| Polymeric polyols |
Polyether polyol (The oxygen atoms of the ether linkages are shown in blue.) |
Polyester polyol (The oxygen and carbon atoms |
The term polyol is used for various chemistries of the molecular backbone. Polyols may be reacted with or polyisocyanates to produce . MDI finds considerable use in PU foam production. Polyurethanes are used to make flexible foam for mattresses and seating, rigid foam insulation for and freezers, elastomeric shoe soles, fibers (e.g. Spandex), coatings, sealants and adhesives.
The term polyol is also attributed to other molecules containing hydroxyl groups. For instance, polyvinyl alcohol is (CH2CHOH) n with n hydroxyl groups where n can be in the thousands. Cellulose is a polymer with many hydroxyl groups, but it is not referred to as a polyol.
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