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Nanoparticle amount, and not size, determines chain alignment and nonlinear hardening in polymer nanocomposites.

ABSTRACT: Polymer nanocomposites-materials in which a polymer matrix is blended with nanoparticles (or fillers)-strengthen under sufficiently large strains. Such strain hardening is critical to their function, especially for materials that bear large cyclic loads such as car tires or bearing sealants. Although the reinforcement (i.e., the increase in the linear elasticity) by the addition of filler particles is phenomenologically understood, considerably less is known about strain hardening (the nonlinear elasticity). Here, we elucidate the molecular origin of strain hardening using uniaxial tensile loading, microspectroscopy of polymer chain alignment, and theory. The strain-hardening behavior and chain alignment are found to depend on the volume fraction, but not on the size of nanofillers. This contrasts with reinforcement, which depends on both volume fraction and size of nanofillers, potentially allowing linear and nonlinear elasticity of nanocomposites to be tuned independently.

SUBMITTER: Varol HS

PROVIDER: S-EPMC5402406 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Nanoparticle amount, and not size, determines chain alignment and nonlinear hardening in polymer nanocomposites.

Varol H Samet HS Meng Fanlong F Hosseinkhani Babak B Malm Christian C Bonn Daniel D Bonn Mischa M Zaccone Alessio A Parekh Sapun H SH

Proceedings of the National Academy of Sciences of the United States of America 20170404 16

Polymer nanocomposites-materials in which a polymer matrix is blended with nanoparticles (or fillers)-strengthen under sufficiently large strains. Such strain hardening is critical to their function, especially for materials that bear large cyclic loads such as car tires or bearing sealants. Although the reinforcement (i.e., the increase in the linear elasticity) by the addition of filler particles is phenomenologically understood, considerably less is known about strain hardening (the nonlinear ...[more]

PMID: 28377517

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Dataset Information

Nanoparticle amount, and not size, determines chain alignment and nonlinear hardening in polymer nanocomposites.

Publications

Nanoparticle amount, and not size, determines chain alignment and nonlinear hardening in polymer nanocomposites.

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