Dynamics of Polymer Networks with Strong Differences in the Viscous Characteristics of their Crosslinks and Strands

✍ Scribed by Vladimir P. Toshchevikov; Alexander Blumen; Yulii Ya. Gotlib

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 474 KB
• Volume: 16
• Category: Article
• ISSN: 1022-1344
• DOI: 10.1002/mats.200600081

✦ Synopsis

Abstract

We study theoretically the relaxation properties of polymer networks, whose monomers and junction sites have different friction parameters (ζ and ζ~jun~, respectively). For this, we focus on topologically regular cubic networks built from “bead‐and‐spring” Rouse chains. Setting σ = ζ~jun~/ζ, we determine analytically both the eigenvalues and the eigenmodes of the model for arbitrary values of σ. This allows us to extend previous approaches (Macromolecules 2000, 33, 6578) which were restricted by the condition σ = 3. We compute the frequency dependent storage, G′(ω), and loss, G″(ω), moduli (which for σ ≫ 3 or σ ≪ 3 display two plateaus and two maxima, respectively) and also the mean‐square displacements of the network junctions and of the beads; these turn out to obey power laws, whose validity ranges depend on σ.

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