TY - JOUR
T1 - Reversible thermal stiffening in polymer nanocomposites
AU - Senses, Erkan
AU - Isherwood, Andrew
AU - Akcora, Pinar
N1 - Publisher Copyright:
© 2015 American Chemical Society.
PY - 2015/7/15
Y1 - 2015/7/15
N2 - Miscible polymer blends with different glass transition temperatures (Tg) are known to create confined interphases between glassy and mobile chains. Here, we show that nanoparticles adsorbed with a high-Tg polymer, poly(methyl methacrylate), and dispersed in a low-Tg matrix polymer, poly(ethylene oxide), exhibit a liquid-to-solid transition at temperatures above Tg's of both polymers. The mechanical adaptivity of nanocomposites to temperature underlies the existence of dynamically asymmetric bound layers on nanoparticles and more importantly reveals their impact on macroscopic mechanical response of composites. The unusual reversible stiffening behavior sets these materials apart from conventional polymer composites that soften upon heating. The presented stiffening mechanism in polymer nanocomposites can be used in applications for flexible electronics or mechanically induced actuators responding to environmental changes like temperature or magnetic fields.
AB - Miscible polymer blends with different glass transition temperatures (Tg) are known to create confined interphases between glassy and mobile chains. Here, we show that nanoparticles adsorbed with a high-Tg polymer, poly(methyl methacrylate), and dispersed in a low-Tg matrix polymer, poly(ethylene oxide), exhibit a liquid-to-solid transition at temperatures above Tg's of both polymers. The mechanical adaptivity of nanocomposites to temperature underlies the existence of dynamically asymmetric bound layers on nanoparticles and more importantly reveals their impact on macroscopic mechanical response of composites. The unusual reversible stiffening behavior sets these materials apart from conventional polymer composites that soften upon heating. The presented stiffening mechanism in polymer nanocomposites can be used in applications for flexible electronics or mechanically induced actuators responding to environmental changes like temperature or magnetic fields.
KW - adaptive
KW - confinement
KW - dynamic coupling
KW - interphase
KW - miscible blend
KW - polymer nanocomposite
KW - reversible stiffening
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U2 - 10.1021/acsami.5b02046
DO - 10.1021/acsami.5b02046
M3 - Article
AN - SCOPUS:84937138668
SN - 1944-8244
VL - 7
SP - 14682
EP - 14689
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 27
ER -