Enhancement to the rate-dependent mechanical behavior of polycarbonate by incorporation of triptycenes
| Autor: | Mary C. Boyce, Yong Yang, Nicholas T. Tsui, Adam D. Mulliken, Lokman Torun, Edwin L. Thomas, Timothy M. Swager |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
chemistry.chemical_classification
Materials science Polymers and Plastics Organic Chemistry Polymer Strain rate Crystallinity chemistry.chemical_compound Compressive strength chemistry visual_art Triptycene Ultimate tensile strength Materials Chemistry visual_art.visual_art_medium Polymer blend Polycarbonate Composite material |
| Zdroj: | Polymer. 49:4703-4712 |
| ISSN: | 0032-3861 |
| DOI: | 10.1016/j.polymer.2008.08.038 |
| Popis: | The tensile and compressive properties of triptycene-polycarbonates were tested over 6 orders of magnitude in strain rate. Initially we studied a low molecular weight, low triptycene content PC blended with Iupilon ® PC and then a series of higher molecular weight, higher triptycene content polymers. The PC blend with only 1.9 wt% triptycene displayed up to 20% increase in modulus and up to 17% increase in yield strength with elongations over 80% as compared to the Iupilon ® PC. The higher molecular weight T-PCs (up to 26 wt% triptycene) exhibited improvements in modulus by over 20% and improvements in compressive strengths by nearly 50% at both low and high strain rates without any apparent sacrifice to ductility, as compared to Iupilon ® PC. All samples containing triptycene units retained transparency and exhibited no signs of crystallinity or phase separation. Moreover, both the blends and triptycene-PC copolymers displayed significantly altered dynamic mechanical spectra, specifically, the emergence of a pronounced, new β′ relaxation approximately 75 °C above the traditionally observed β relaxation in PC (approximately −100 °C). The enhancement of the mechanical properties observed provides valuable insights into the unique packing and interactions during plastic flow induced by the presence of triptycene units. |
| Databáze: | OpenAIRE |
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