Aq. Na bisphenolate reacted in a two-phase system at 0-30degreesC with isophthalic and terephthalic acid dichlorides in CH2Cl2 as solvent and DMSO as catalyst (100 mole % based on bisphenol) to yield fire-safe polyarylates. The NaDMSO+ cation was stable during the reaction and formed an ion-pair with bisphenolate. DMSO proved to be a very efficient phase-transfer catalyst. Solid epoxy resins were prepared by fusing a low-M bisphenol epoxy resin (GY 250; epoxy value, 0.538) containing a catalyst, bisphenol A, and CBF II as fire retardant used in varying amounts. Viscosity, FTIR spectra and oxygen index were determined.