| People | Locations | Statistics |
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| Naji, M. |
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| Motta, Antonella |
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| Aletan, Dirar |
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| Mohamed, Tarek |
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| Ertürk, Emre |
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| Taccardi, Nicola |
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| Kononenko, Denys |
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| Petrov, R. H. | Madrid |
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| Alshaaer, Mazen | Brussels |
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| Bih, L. |
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| Casati, R. |
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| Muller, Hermance |
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| Kočí, Jan | Prague |
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| Šuljagić, Marija |
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| Kalteremidou, Kalliopi-Artemi | Brussels |
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| Azam, Siraj |
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| Ospanova, Alyiya |
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| Blanpain, Bart |
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| Ali, M. A. |
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| Popa, V. |
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| Rančić, M. |
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| Ollier, Nadège |
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| Azevedo, Nuno Monteiro |
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| Landes, Michael |
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| Rignanese, Gian-Marco |
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Yu, Donghong
Aalborg University
in Cooperation with on an Cooperation-Score of 37%
Topics
Publications (7/7 displayed)
- 2023The Effect of Physical Aging on the Viscoelastoplastic Response of Glycol Modified Poly(ethylene terephthalate)citations
- 2023Accelerated physical aging of four PET copolyesterscitations
- 2023Accelerated physical aging of four PET copolyesters:Enthalpy relaxation and yield behaviourcitations
- 2022Resolving the Conflict between Strength and Toughness in Bioactive Silica–Polymer Hybrid Materialscitations
- 2019Multiscale Characterization of a Wood-Based Biocrude as a Green Compatibilizing Agent for High-Impact Polystyrene/Halloysite Nanotube Nanocompositescitations
- 2013Synthesis and photovoltaic properties from inverted geometry cells and roll-to-roll coated large area cells from dithienopyrrole-based donor–acceptor polymerscitations
- 2013Synthesis and photovoltaic properties from inverted geometry cells and roll-to-roll coated large area cells from dithienopyrrole-based donor–acceptor polymerscitations
Places of action
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article
Accelerated physical aging of four PET copolyesters
Abstract
<p>Assessing suitability of amorphous polymers in durable products requires understanding of long-term effects of physical aging on the material properties. This work shows four polyesters with varying diol composition (poly(ethylene-co-1,4-cyclohexylenedimethylene terephthalate) (PETG1 and PETG2 with ∼30 and ∼60% 1,4-cyclohexylenedimethylene (CHDM), respectively), poly(ethylene-co-2,2,4,4-tetramethyl-1,3-cyclobutanediol terephthalate) (PETT) with ∼30% 2,2,4,4-tetramethyl-1,3-cyclobutanediol (TMCD) and poly(1,4-cyclohexylenedimethylene-co-2,2,4,4-tetramethyl-1,3-cyclobutanediol terephthalate) (PCTT) with ∼80% CHDM and ∼20% TMCD) exposed to thermal treatment at 20, 30 and 40 °C below their respective glass transition temperatures for up to 504 h to accelerate physical aging. The enthalpy relaxation was investigated by differential scanning calorimetry and compared to mechanical changes manifested as tensile yield strength increase. The physical aging rates were found to depend on both chemical structure and composition of CHDM and TMCD segments, where the introduction of TMCD inhibited physical aging. Arrhenius and Vogel-Fulcher-Tamman models were used to fit horizontal shift factors and evaluate the time and temperature dependencies for each polyester. From this study, the two models showed no significant differences in ability to describe the effects of physical aging. The Arrhenius activation energies, E<sub>a</sub>, were all in the range 118–244 kJ mol<sup>−1</sup>, were both PETG1 and PETG2 showed no significant difference between E<sub>a</sub> for enthalpy relaxation and yield strength increase, whereas PETT and PCTT showed ∼19 and ∼107% difference between the two, respectively, suggesting that the relationship between the two phenomena is not independent of chemical structure. The difference between the activation energies suggests that the time scales for physical aging are different when observed as enthalpy relaxation and yield strength.</p>