On the mechanism of pinning in phase-separating polymer blends
نویسندگان
چکیده
We re-explore the kinetics of spinodal decomposition in off-critical polymer blends through numerical simulations of the Cahn-Hilliard equation with the Flory-Huggins-De Gennes free energy functional. Even in the absence of thermal noise, the solution of the discretized equation of motion shows coarsening in the late stages of spinodal decomposition without evidence of pinning, regardless of the relative concentration of the blend components. This suggests this free energy functional is not sufficient to describe the physics responsible for pinning in real blends. Permanent address: Dipartimento di Scienze Fisiche, Università degli studi di Napoli, Pad. 19, Mostra d’Oltremare, Napoli 80125, Italy. Internet address: [email protected] Internet address: [email protected] 1
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