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Poly(aryl ether phenylquinoxalines) via anionic ring opening polymerization of macrocycles
Author(s) -
Srinivasan S.,
Hedrick J. L.,
Chan K. P.,
Hawker C. J.,
Twieg R.
Publication year - 1997
Publication title -
macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 1022-1360
DOI - 10.1002/masy.19971220117
Subject(s) - polymerization , polymer chemistry , chemistry , molar mass distribution , aryl , ring opening polymerization , toluene , potassium carbonate , ether , solution polymerization , polymer , alkyl , organic chemistry
A cyclic poly(aryl ether phenylquinoxaline) was prepared via the self‐polymerization of 1 in an N‐methyl‐2‐pyrrolidone (NMP) solution containing base using a pseudo‐high dilution polymerization condition. The macrocycle formation of 1 was carried out in the presence of potassium carbonate in a NMP/toluene solvent mixture at a solids content of 1%. The water generated by phenoxide formation was removed as an azeotrope with toluene 170 °C. A concentrated solution of the macrocycle was added to the reaction mixture over an 8 hour period. The reaction was allowed to proceed for an additional 24h to ensure quantitative reaction. A number of characterization techniques were used to study the cyclization of 1 including GPC, HPLC, H NMR and matrix‐assisted laser desorption ionization (MALDI) mass spectroscopy. The MALDI‐TOF mass spectrum of the cyclization of 1 clearly showed that a mixture of macrocycles is obtained, with the expected distribution of molecular weights. Facile ring opening polymerization of the cyclic poly(aryl ether phenylquinoxaline) oligomers was accomplished with a nucleophilic initiator. High polymer was obtained for each polymerization temperature (η = 0.4–0.5 dl/g in NMP), however, prolonged reaction time resulted in significant gel formation. The Tg's were high and commensurate with the high molecular weight linear analog (250 °C).