Synthesis and ring-opening polymerization of macrocyclic aromatic sulfide oligomers

A series of macrocyclic(arylene sulfide) oligomers were synthesized by reaction of 4,4'-oxybis(benzenethiol) with a number of difluoro, compounds in dimethylformamide (DMF) in the presence of anhydrous K2CO3 under high dilution conditions. The difluoro, compound can be 4,4'-difluorobenzophenone, bis(4-fluorophenyl)sulfone or 1,3-bis(4-fluorobenzoyl)benzene. Detailed structural characterization of these oligomers by matrix-assisted laser desorption and ionization-time of flight-mass spectroscopy (MALDI-TOF-MS) demonstrated their cyclic nature. The MALDI-TOF-MS technique has proved to be a powerful tool to analyze these cyclics. These cyclic oligomers are amorphous and highly soluble in DMF and N,N'-dimethyl acetamide. Moreover, these cyclic(arylene sulfide) oligomers readily underwent ring-opening polymerization in the melt at 285degreesC in the presence of 2,2'-dibenzothiazole disulfide, affording linear, high molecular weigh poly(aromatic sulfide)s. These polymers are insoluble in most common solvents. (C) 2004 Society of Chemical Industry.