Structure–property behavior of segmented polyurethaneurea copolymers based on an ethylene–butylene soft segment

Autor: Frederick L. Beyer, Derek B. Klinedinst, Garth L. Wilkes, Emel Yilgor, Iskender Yilgor
Rok vydání: 2005
Předmět:
Zdroj: Polymer. 46:10191-10201
ISSN: 0032-3861
DOI: 10.1016/j.polymer.2005.07.065
Popis: Novel segmented polyurethaneurea copolymers were synthesized using a poly(ethylene–butylene) glycol based soft segment and either hydrogenated diphenyl methane diisocyanate (HMDI) or hexamethylene diisocyanate (HDI) in addition to either ethylene diamine (EDA) or 2-methyl-1,5-diaminopentane (DY) as the chain extender. Dynamic mechanical analysis (DMA), small angle X-ray scattering (SAXS) and in some cases atomic force microscopy (AFM) established the presence of a microphase-separated structure in which hard microdomains are dispersed throughout a soft segment matrix. Wide angle X-ray scattering (WAXS) and differential scanning calorimetry (DSC) imply that the materials are amorphous. Samples that are made with HMDI/DY and have hard segment contents in the range of 16–23 wt% surprisingly exhibit near-linear mechanical deformation behavior in excess of 600% elongation. They also show very high levels of recoverability even though their hysteresis is also considerable. The materials have all proven to be melt processable in addition to solution processable.
Databáze: OpenAIRE