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Polyols may be classified according to their chemistry. [5] Some of these chemistries are polyether, polyester, [6] polycarbonate [7] [8] and also acrylic polyols. [9] [10] Polyether polyols may be further subdivided and classified as polyethylene oxide or polyethylene glycol (PEG), polypropylene glycol (PPG) and Polytetrahydrofuran or PTMEG.
Its major application is its use for the production of polyether polyols for use in making polyurethane plastics. It is a chiral epoxide, although it is commonly used as a racemic mixture. This compound is sometimes called 1,2-propylene oxide to distinguish it from its isomer 1,3-propylene oxide, better known as oxetane.
PO is mainly used for alkoxylation to produce polyether polyols. The alkoxylation process is shown in simplified form: ROH + n OCH 2 CHCH 3 → R(OCH 2 CHCH 3) n OH. Polyols derived from PO have complex stereochemistry owing to the chirality of the propylene oxide.
Chemically it is a polyether, and, more generally speaking, it's a polyalkylene glycol (PAG) H S Code 3907.2000. The term polypropylene glycol or PPG is reserved for polymer of low- to medium-range molar mass when the nature of the end-group , which is usually a hydroxyl group, still matters.
They are produced by reacting either ethylene oxide or propylene oxide with polyols and then aminating them. There are a number of commercially available molecules with different CAS numbers and molecular weights. They often come with a prefix of M, D or T for monofunctional, difunctional and trifunctional respectively.
The term polyol generally refers to polyether polyols with one or more functional end-groups such as a hydroxyl group. The term "oxide" or other terms are used for high molar mass polymer when end-groups no longer affect polymer properties. Crown ethers are cyclic polyethers.
Graft polyols (also called filled polyols or polymer polyols) contain finely dispersed styrene–acrylonitrile, acrylonitrile, or polyurea (PHD) polymer solids chemically grafted to a high molecular weight polyether backbone. They are used to increase the load-bearing properties of low-density high-resiliency (HR) foam, as well as add toughness ...
The material is a mixture of polyether diols terminated with alcohol groups. It is produced by polymerization of tetrahydrofuran as well as 1,4-butanediol. The product is commercially available as polymers of low average molecular weights, between 250 and 3000 daltons. In this form it is a white waxy solid that melts between 20 and 30 °C.