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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.
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.
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.
Moisture cured polyurethane–urea coatings have been made by reacting 1,2,3-triazole rich polyether polyols with HMDI at NCO/OH eq. ratio of 1.2 to obtain isocyanate-terminated polyurethane prepolymers. The prepolymers were cured under atmospheric moisture to make polyurethane–urea free films.
A linear polyether, e.g. used in cosmetics and pharmaceuticals. Polypropylene glycol: A linear polyether, e.g. used in polyurethanes. Platelet-activating factor An ether lipid, an example with an ether on sn-1, an ester on sn-2, and an inorganic ether on sn-3 of the glyceryl scaffold.
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The generalised chemical structure of polyisocyanurate showing the isocyanurate group. The polyols are abbreviated as R-groups.. Polyisocyanurate (/ ˌ p ɒ l ɪ ˌ aɪ s oʊ s aɪ ˈ æ nj ʊər eɪ t /), also referred to as PIR, polyol, or ISO, is a thermoset plastic [1] typically produced as a foam and used as rigid thermal insulation.
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.