Influence of Microstructure on Micro-/Nano-Mechanical Measurements of Select Model Transparent Poly(urethane urea) Elastomers
Abstract
Morphology of 4,40 -dicyclohexylmethane diisocyanateepoly(tetramethylene oxide) (PTMO)ediethyl toluenediamine based poly(urethane urea) (PUU) elastomers is investigated by atomic force microscopy (AFM) and compared with elastic modulus data measured from AFM-enabled indentation, dynamic nanoindentation (nanoDMA), and dynamic mechanical analysis (DMA). These measurements highlight the effect of altering the molecular weight (Mw) of PTMO, which is used as a soft segment (SS), on the microstructure. In particular, at SS Mw 2000 g/mol, a strong microphase-separated morphology is observed, whereas a phase-mixed dominated microstructure is noted in PUU with SS Mw of 1000 and 650 g/mol. These observations are also consistent with DMA tan d results. Furthermore, instrumented impact indentation is also utilized for elucidation of dynamic damping characteristics in these PUUs.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 17, 2012
- Accession Number
- ADA607948
Entities
People
- Alex J. Hsieh
- Kenneth E Strawhecker
- Krystyn Van Vliet
- Tanya L. Chantawansri
- Z. I. Kalcioglu
Organizations
- United States Army Research Laboratory