Polyether Diols and Triols, Copolymers THF-alkylene Oxides

3 Polyether Diols and Triols, Copolymers THF-alkylene Oxides 

The cationic catalysts of this copolymerisation reaction are Lewis acids (BF3, SbF5, PF5) or superacids, such as (HBF4, HSbF6, HPF6, CF3S03H) [33-38, 54, 56-59]. 

In the presence of a polyolic compound used as starter, the Lewis acid generates in situ complex superacids  

The copolymerisation of THF with alkylene oxides (PO, EO, epichlorohydrin and so on), catalysed by strongly acidic species, is perfectly explained by the activated monomer mechanism presented before (Section 7.2). 

In the reaction medium there are two activated species activated oxirane and activated THF [54, 55]. 

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