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High Molar Mass Polycarbonate via Dynamic Solution Transcarbonation Using Bis(methyl salicyl) Carbonate, an Activated Carbonate
Author(s) -
Aerts Annelore,
Kroonen Camiel,
Kamps Jan Henk,
Sijbesma Rint P.,
Heuts Johan P. A.
Publication year - 2021
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.202100186
Subject(s) - polycarbonate , condensation polymer , diphenyl carbonate , chemistry , molar mass , monomer , carbonate , bisphenol a , polymerization , polymer chemistry , dimethyl carbonate , polymer , organic chemistry , catalysis , transesterification , epoxy
High molar mass polycarbonate is synthesized via a solution transcarbonation of bis(methyl salicyl) carbonate and bisphenol‐A at temperatures between 60 and 160 °C without the removal of the condensate, allowing the incorporation of thermosensitive monomers into polycarbonate. Kinetic and equilibrium studies show that the polymerization is 20–30 times faster at 120 °C compared to 60 °C, whereas the equilibrium M w increases from 11 × 10 3 g mol −1 at 120 °C to 16 × 10 3 g mol −1 at 60 °C. This polycondensation is characterized by very high equilibrium constants ranging from 0.8 × 10 3 at 160 °C to 4.1 × 10 3 at 60 °C, corresponding to standard enthalpies and entropies of polymerization: −19 kJ mol −1 < Δ H 0 < −11 kJ mol −1 and 13 J mol −1 K −1 < Δ S 0 < 28 J mol −1 K −1 . Without removal of the condensate, the system is shown to be dynamic and completely reversible when changing the temperature. Good predictability of this polycondensation is reported, where only at very low starting monomer concentrations, the formation of cyclics leads to deviations from the predicted behavior.