Polymerization of carbazolyl-containing epoxides with triphenylcarbenium salts
Author(s) | |
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Brūzga, Pranas | Kauno technologijos universitetas |
Gražulevičius, Juozas Vidas | Kauno technologijos universitetas |
Kavaliūnas, Rimtautas | Kauno technologijos universitetas |
Kauno technologijos universitetas | |
Liutvinienė, Ina | Kauno technologijos universitetas |
Date Issued |
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1993-03-07 |
Polymerization of 9-(2,3-epoxypropyl)carbazole (EPC) and 1,2-epoxy-6-(9-carbazolyl)-4-oxahexane (ECOH) with triphenylearbenium hexachloroantimonate and triphenylcarbenium tetrafluoroborate have been studied by the microoalorimetric technique. Triphenylcarbenium salts have turn out to be more efficient catalyst for the polymerization of carbazolyl-containing epoxides than Lewis acids, giving high yields at low initial concentration of the catalyst. Using comparatively restricted conditions of reaction ([triphenylcarbenium salt]o greater-than-or-equal-to 0.02 mol/l, t greater-than-or-equal-to 50-degrees-C) transition from the conventional active chain end mechanism to the activated monomer mechanism has been observed at a sufficiently high degree of conversion ofmonomer.