Lali Vakhtangishvili

SYNTHESES OF BRANCHED POLY(ETHER KETONE)S WITH PENDANT FUNCTIONAL GROUPS BASED ON 1,1,1-TRIS(4-HYDROXYPHENYL)ETHANE

ABSTRACT 1,1,1-Tris(4-hydroxyphenyl)ethane, THPE, was silylated with chlorotrimethylsilane and the silylated THPE was polycondensed with 1,4-bis(4-fluorobenzoyl)benzene, BFBB, in dry N-methylpyrrolidone. The resulting poly(ether ketone) had a moderate molecular weight and contained a significant fraction of cyclic oligomers and polymers. The pendant trimethylsiloxy group allowed an in situ alkylation with chloropropionitrile, allylbromide, 3,4-dichlorobenzyl chloride, 4-nitrobenzyl bromide, 1,3-propane sultone and 1,4-butane sultone. The latter alkylating agents yielded poly(ether ketone)s having pendant sulfonic acid groups. Further functional groups were introduced by acylation of the pendant free OH-group (resulting from the hydrolysis of the Me3SiO group) with acetic anhydride, methacrylic anhydride, cinnamoyl chloride and undecenoyl chloride.

Macrocycles 32. Syntheses of Cyclic Poly(Ether Ketone)s of Bisphenol-A

Two classes of poly(ether ketone)s were prepared from bisphenol-A, namely by polycondensation with 4, 4′-difluorobenzophenone or with 2,6-difluorobenzophenone and 4′-tert.butyl-2,6-difluorobenzophenone. Two different synthetic methods were compared. First, polycondensations of the free bisphenol-A in DMSO or sulfolane with azeotropic distillation of water. Second, polycondensations of bistrimethylsilyl bisphenol-A in N-methylpyrrolidone. The second approach gave higher yields and higher molecular weights (Mn values up to 85000 Da and Mw values up to 190000 Da). The matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectra revealed that the fraction of cyclic oligomers and polymers systematically increased with higher molecular weights. A few polycondensations of silylated 4-tert.butylcatechol with 4, 4′-difluorobenzophenone confirmed the trends observed for silylated bisphenol-A. Under optimum conditions cyclic poly(ether ketone)s were detectable in the MALDI-TOF mass spectra up to molecular weights of 18 000 Da.