PREPARATION AND PROPERTIES OF HYPERBRANCHED POLY(ETHER KETONES) WITH A VARIOUS NUMBER OF PHENYLENE UNITS

New AB(2) type monomers, with a various number of phenylene units, wer e prepared and converted to hyperbranched poly(ether ketones) by polym erization. Four kinds of AB(2) type monomers, 4-hydroxy-3',5'-bis(4-fl uorobenzoyl)-biphenyl, 1, 4-hydroxy-3 '',5 '' bis(4-fluorobenzoyl)-p-t erphenyl, 2, 4-hydroxy-3 3''',5'''-bis(4-fluorobenzoyl)-o-quarterpheny l, 3, and -3'''',5''''-bis(4-fluorobenzoyl)-p-quinquephenyl, 4, were s ynthesized in a stepwise manner starting from 3,5-bis(4-fluorobenzoyl) phenol, 5, repeating a series of conversions of the hydroxy group to t he triflate, cross-coupling reaction of the triflate with (p-methoxyph enyl)boronic acid, and cleavage of the methyl ether. Four kinds of hyp erbranched poly(ether ketones) were prepared by the polymerization of the four AB(2) type monomers. Obtained hyperbranched poly(ether ketone s) from 1 and 2 were soluble in various organic solvents including N-m ethyl-2-pyrrolidone, m-cresol, chloroform, and tetrahydrofuran, but th ose from 3 and 4 were insoluble in organic solvents. The thermal prope rties of these hyperbranched poly(ether ketones) depended on the numbe r of the phenylene units. The values of the glass transition temperatu re increased with increasing number of the phenylene units, and only h yperbranched poly(ether ketone) from 5 showed crystalline character. T he thermal properties of these hyperbranched poly(ether ketones) were compared with those of hyperbranched poly(ether ketones) having variou s numbers of phenylene units in the chain ends.