title: Well-defined biobased segmented polyureas synthesis via a TBD-catalyzed isocyanate-free route.
abstract: 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 (Tfl ) 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.
authors.affiliation: Laboratory of Polymer Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands; Dutch Polymer Institute DPI, PO Box 902, 5600 AX Eindhoven, The Netherlands.
authors.forename: Donglin
authors.initials: D
authors.lastname: Tang
authors.forename: Dirk-Jan
authors.initials: DJ
authors.lastname: Mulder
authors.forename: Bart A J
authors.initials: BA
authors.lastname: Noordover
authors.forename: Cor E
authors.initials: CE
authors.lastname: Koning
mesh_terms: D001672:Biocompatible Materials; D001643:Bridged Bicyclo Compounds / Q000737:chemistry*; D002219:Carbamates / Q000737:chemistry*; D002384:Catalysis; D006146:Guanidines / Q000737:chemistry*; D017953:Isocyanates; D008422:Materials Testing; D015394:Molecular Structure; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry*; D011409:Propylene Glycols / Q000737:chemistry*; D013696:Temperature
chemical_list: D001672:Biocompatible Materials; D001643:Bridged Bicyclo Compounds; D002219:Carbamates; D006146:Guanidines; D017953:Isocyanates; D011108:Polymers; D011409:Propylene Glycols; C012504:polypropylene glycol; C045786:polyurea