Polymers of Carbonic Acid, 31. Cyclic Polycarbonates by Hydrolytic Polycondensation of Bisphenol‐A Bischloroformate

The hydrolytic polycondensation of bisphenol‐A bischloroformate in NaOH/CH₂Cl₂ was studied using triethylamine as the catalyst. Reaction conditions were optimized towards high molar masses. The isolated polycarbonates were characterized by means of SEC and MALDI‐TOF mass spectrometry. The fraction of cyclic polycarbonates strongly increased with higher molecular weights and in the best sample only cycles were detectable (up to 50 000 Da). The largest cycles can compete with cyclic DNS of microorganisms.