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Polycondensations of Bisphenol‐A with Diphosgene or Triphosgene in Water‐Free Organic Solvents
Author(s) -
Kricheldorf Hans R.,
Böhme Sigrid,
Schwarz Gert
Publication year - 2005
Publication title -
macromolecular chemistry and physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.57
H-Index - 112
eISSN - 1521-3935
pISSN - 1022-1352
DOI - 10.1002/macp.200400398
Subject(s) - triphosgene , triethylamine , pyridine , chemistry , dispersity , dichloromethane , polymer chemistry , bisphenol a , mass spectrum , molecular mass , mass fraction , nuclear chemistry , organic chemistry , mass spectrometry , chromatography , solvent , epoxy , enzyme , phosgene
Summary: Bisphenol‐A was polycondensed with diphosgene and excess pyridine in a mixture of dry dichloromethane and 1,4‐dioxane. The stoichiometry was varied to optimize the molecular weight. According to MALDI‐TOF mass spectra the fraction of cyclic polycarbonates increased with higher molecular weights. Analogous results were obtained with triphosgene. When pyridine was replaced by triethylamine, diethyl carbamoyl chloride was formed and an excess of diphosgene (plus triethylamine) yielded polycarbonates having one or two diethylcarbamate endgroups. However, the content of cycles increased again with the molecular weight and peaked for the sample with the maximum molecular weight. 1 H NMR endgroup analyses confirmed the interpretation of the MALDI‐TOF mass spectra. SEC measurement indicated high polydispersity indices (around 7) for samples rich in cycles.