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Well‐defined Biobased Segmented Polyureas Synthesis via a TBD‐catalyzed Isocyanate‐free Route
Author(s) -
Tang Donglin,
Mulder DirkJan,
Noordover Bart A. J.,
Koning Cor E.
Publication year - 2011
Publication title -
macromolecular rapid communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.348
H-Index - 154
eISSN - 1521-3927
pISSN - 1022-1336
DOI - 10.1002/marc.201100223
Subject(s) - superbase , isocyanate , dispersity , materials science , elastomer , dynamic mechanical analysis , glass transition , catalysis , polymer chemistry , polyurea , polymerization , chemical engineering , polymer , polyurethane , composite material , organic chemistry , chemistry , engineering
Via an isocyanate‐free route, a series of segmented polyureas (PUs) were synthesized from (potentially) renewable resources. To the best of our knowledge, the present work shows for the first time that the organic superbase guanidine 1,5,7‐triazabicyclododecene (TBD) which was originally developed as a catalyst for the ring‐opening polymerization of lactones, lactides or cyclic carbonates, is also a promising catalyst for the transurethanization between dicarbamates and diamino‐terminated poly(propylene glycol) (PPGda) providing PUs via an isocyanate‐free strategy. The renewable segmented PUs contain monodisperse hard segments (HSs). This well‐defined structure was verified by the DMTA plots of the PUs, showing a sharp glass transition, a sharp flow transition and a flat rubbery plateau. The flow and maximum use temperature ( T fl ) of the PUs increases with the increasing number of urea groups in the corresponding dicarbamates. In addition, at constant HS length, the length of the soft‐segment (SS) can be changed to adjust the properties of the PU materials, enabling their application as adhesives, soft elastomers, or rigid plastics.