Phase stability and dynamics of entangled polymer-nanoparticle composites

Journal Article · Wed Jun 10 04:00:00 EDT 2015 · Nat. Commun.

DOI:https://doi.org/10.1038/ncomms8198· OSTI ID:1184251

Mangal, Rahul; Srivastava, Samanvaya; Archer, Lynden A. ^[1]

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1. UC

Nanoparticle–polymer composites, or polymer–nanoparticle composites (PNCs), exhibit unusual mechanical and dynamical features when the particle size approaches the random coil dimensions of the host polymer. Here, we harness favourable enthalpic interactions between particle-tethered and free, host polymer chains to create model PNCs, in which spherical nanoparticles are uniformly dispersed in high molecular weight entangled polymers. Investigation of the mechanical properties of these model PNCs reveals that the nanoparticles have profound effects on the host polymer motions on all timescales. On short timescales, nanoparticles slow-down local dynamics of the host polymer segments and lower the glass transition temperature. On intermediate timescales, where polymer chain motion is typically constrained by entanglements with surrounding molecules, nanoparticles provide additional constraints, which lead to an early onset of entangled polymer dynamics. Finally, on long timescales, nanoparticles produce an apparent speeding up of relaxation of their polymer host.

• Research Organization: Advanced Photon Source (APS), Argonne National Laboratory (ANL), Argonne, IL (US)
• Sponsoring Organization: NSFFOREIGN
• OSTI ID: 1184251
• Journal Information: Nat. Commun., Journal Name: Nat. Commun. Journal Issue: 2015 Vol. 6
• Country of Publication: United States
• Language: ENGLISH