Alkylene oxide propylene glycol ethers

Polyether Polyols. Polyether polyols are addition products derived from cyclic ethers (Table 4). The alkylene oxide polymerisation is usually initiated by alkah hydroxides, especially potassium hydroxide. In the base-catalysed polymerisation of propylene oxide, some rearrangement occurs to give aHyl alcohol. Further reaction of aHyl alcohol with propylene oxide produces a monofunctional alcohol. Therefore, polyether polyols derived from propylene oxide are not truly diftmctional. By using sine hexacyano cobaltate as catalyst, a more diftmctional polyol is obtained (20). Olin has introduced the diftmctional polyether polyols under the trade name POLY-L. Trichlorobutylene oxide-derived polyether polyols are useful as reactive fire retardants. Poly(tetramethylene glycol) (PTMG) is produced in the acid-catalysed homopolymerisation of tetrahydrofuran. Copolymers derived from tetrahydrofuran and ethylene oxide are also produced. 

PTMO, PEO, poly(propylene oxide) (PPrO), and their random or block copolymers are most often used as flexible segments. Poly(alkylene ether) glycols are synthesized mainly by ring-opening polymerization and radical polymerization. Extensive reviews on the chemical structure and synthesis of oligo(alkylene ether)s with functional end-groups and their copolymers were published by Marfechal [11] and Xie [17]. 

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