Epoxide homopolymerization intermediate

This reaction is in fact the homopolymerization of the epoxide. The reactivity of the secondary hydroxy group with respect to the epoxy group is intermediate between that of tertiary and primary hydroxy group 26). 

We have attempted to account for these observations by proposing the following simplified reaction path (Figure 6). Protonation of the epoxide is followed by the rearrangement of the protonated species to a covalent intermediate or a solvent stabilized ion pair. Homopolymerization then proceeds through the ion-pair intermediate, but the covalent Intermediate leads to catalyst transformation and, in most cases, loss of catalytic activity. 

One would expect the polarity of the solvent to also have a strong effect on the covalent Intermediate formation. Nonpolar solvent should favor the formation of covalent Intermediate which would lead to catalyst transformation. A study of the homopolymerization of cyclohexene oxide In solvents of different polarities Is shown In Figure 9 using bromodlsulfone as a catalyst, and the data shown In Table III Illustrate this Idea. The extent of the exotherm Is dependent on the dielectric constant of these solvents, leading to Incomplete reaction In all cases. Even In the most polar solvent, 1,2-dlchloroethane, 30% unreacted epoxide was found after the reaction was terminated. In the least polar solvent, carbon... 

It does not homopolymerize easily and hence can be stored as a liquid. It undergoes many addition reactions typical of an olefin. Reactions inclnde preparation of linear dimers and trimers and cyclic dimers (21,22) decomposition at 600°C with subsequent formation of octafluoro-2-butene and octafluoroisobutylene (23) oxidation with formation of an epoxide (24), an intermediate for a number of perflu-oroalkyl perfluorovinyl ethers (25,26) and homopolymerization to low molecular weight liquids (27,28) and high molecular weight solids (29,30). Hexafluoropropylene reacts with hydrogen (31), alcohols (32), ammonia (33), and the halogens and their acids, except I2 and HI (31,34-36). It is used as a comonomer to produce elastomers and other copolymers (37-41). The toxicological properties are discussed in Reference 42. 

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