Unraveling the Mechanism of Nanoscale Mechanical Reinforcement in Glassy Polymer Nanocomposites

Cheng, Shiwang; Bocharova, Vera; Belianinov, Alex; Xiong, Shaomin; Kisliuk, Alexander; Somnath, Suhas; Holt, Adam P.; Ovchinnikova, Olga S.; Jesse, Stephen; Martin, Halie J.; Etampawala, Thusitha N.; Dadmun, Mark D.; Sokolov, Alexei P.

doi:10.1021/acs.nanolett.6b00766

Unraveling the Mechanism of Nanoscale Mechanical Reinforcement in Glassy Polymer Nanocomposites

Journal Article · Fri May 20 00:00:00 EDT 2016 · Nano Letters

DOI:https://doi.org/10.1021/acs.nanolett.6b00766· OSTI ID:1271894

Cheng, Shiwang ^[1]; Bocharova, Vera ^[1]; Belianinov, Alex ^[1]; Xiong, Shaomin ^[2]; Kisliuk, Alexander ^[1]; Somnath, Suhas ^[1]; Holt, Adam P. ^[3]; Ovchinnikova, Olga S. ^[1]; Jesse, Stephen ^[1]; Martin, Halie J. ^[3]; Etampawala, Thusitha N. ^[3]; Dadmun, Mark D. ^[3]; Sokolov, Alexei P. ^[4]

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Univ. of California, Berkeley, CA (United States)
Univ. of Tennessee, Knoxville, TN (United States)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)

The mechanical reinforcement of polymer nanocomposites (PNCs) above the glass transition temperature, T_g, has been extensively researched. However, not much is known about the origin of this effect below T_g. In this paper, we unravel the mechanism of PNC reinforcement within the glassy state by directly probing nanoscale mechanical properties with atomic force microscopy and macroscopic properties with Brillouin light scattering. Our results unambiguously show that the "glassy" Young's modulus in the interfacial polymer layer of PNCs is two-times higher than in the bulk polymer, which results in significant reinforcement below T_g. We ascribe this phenomenon to a high stretching of the chains within the interfacial layer. Since the interfacial chain packing is essentially temperature independent, these findings provide a new insight into the mechanical reinforcement of PNCs also above T_g.

View Accepted Manuscript (DOE)

Research Organization:: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)

Sponsoring Organization:: USDOE Office of Science (SC)

Grant/Contract Number:: AC05-00OR22725

OSTI ID:: 1271894

Journal Information:: Nano Letters, Journal Name: Nano Letters Journal Issue: 6 Vol. 16; ISSN 1530-6984

Publisher:: American Chemical SocietyCopyright Statement

Country of Publication:: United States

Language:: English

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36 MATERIALS SCIENCE
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Brillouin light scattering
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band excited atomic force microscopy
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Unraveling the Mechanism of Nanoscale Mechanical Reinforcement in Glassy Polymer Nanocomposites

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