Term: Polyol
**Types of Polyols:**
– Polyols can be classified into polyether, polyester, polycarbonate, and acrylic polyols.
– Polyether polyols include polyethylene oxide, polyethylene glycol (PEG), polypropylene glycol (PPG), and Polytetrahydrofuran (PTMEG).
– Polycaprolactone polyols are commercially available.
– There is a trend towards using biobased polyols.
– Different types of polyols are used in coatings, adhesives, sealants, and elastomers.
**Applications of Polyols:**
– Polyether polyols are used in polyurethane foam production.
– Polyester polyols are used for producing rigid foam.
– Acrylic polyols are preferred for UV stability and lower VOC coatings.
– Caprolactone-based polyols offer enhanced hydrolysis resistance.
– Polycarbonate polyols find use in demanding applications like glass coatings.
**Low Molecular Weight Polyols:**
– Serve as crosslinking agents and chain extenders in polymer chemistry.
– Used in alkyd resins for paints and casting molds.
– Common examples include pentaerythritol and xylitol.
– Used in polyurethane prepolymer production.
**Sugar Alcohols:**
– Obtained through sugar hydrogenation.
– Lower caloric content than sugars.
– Commonly used in food products and chewing gum.
– Examples include maltitol, sorbitol, xylitol, erythritol, and isomalt.
**Renewable Source Polyols:**
– Derived from renewable sources like plant-based materials.
– Vegetable oils and biomass can be used.
– Seed oil can produce polyester polyols.
– Offer sustainable alternatives for polyurethane systems.
In organic chemistry, a polyol is an organic compound containing multiple hydroxyl groups (−OH). 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 diols, triols, and tetrols, respectively.