Polymerization of propylene oxide by the Pruitt-Baggett catalyst

Abstract

The Pruitt-Baggett adduct (PBA) which formed from the reaction of FeCl 3 with propylene oxide (PO) was hydrolysed in diethyl ether (ether) solutions at different r = H 2 O Fe mole ratios. Although the hydrolysates were insoluble in ether they could be converted into PO-soluble form (PBC) by a thermal treatment providing that the r value was kept smaller or equal to unity. PBC polymerized PO concurrently into a mixture of high molecular weight crystalline polymer with low molecular weight non-crystallizable oligomers. The traces catalytic activity shown by PBA substantially enhanced as the hydrolysis ratio r, increased from 0 to 0.5. Although the PBC obtained at r = 0.50 gave maximum yield of polymer, the maximum stereoregular yield (crystalline polymer/oligomer mass ratio) was observed at r = 2 3 mole ratio.