| Abstract: | Polyethers were prepared from 3,3,3-trifluoro-1,2-epoxypropane by using both cationic and anionic initiators. Aluminum chloride and boron trifluoride were the two cationic initiators investigated. The polymer obtained with the use of aluminum chloride contained no functional endgroups other than hydroxyl, while the polymer prepared with boron trifluoride contained some terminal unsaturation. Potassium hydroxide and the monosodium salt of hexafluoropentanediol were investigated as anionic initiators. The polymer obtained by using potassium hydroxide also contained terminal unsaturation, while the polymer prepared with the monosodium salt of hexafluoropentanediol was terminated with primary hydroxyl groups capable of being used in polyurethanes. All polymers had molecular weights in the range from 970 to 4300. A fluorine-containing polyformal was prepared in high yield by the reaction of hexafluoropentanediol with trioxane. The same polymer was obtained in poor yield by the reaction of hexafluoropentanediol with dibutyl formal. Ring-opening polymerizations were attempted on two fluorinated cyclic ethers, 2,2,3,3,4,4-hexafluoropentamethylene oxide and 3,3,4,4-tetrafluorotetramethylene oxide. There was no reaction with anionic initiators. With most of the cationic initiators, there was no reaction. Boron trifluoride and phosphorus pentafluoride formed complexes with the ether, but would not cause ring opening. |
