Molecular Dynamics Simulation of Reactive Compatibilization of Polymer Blends

Autor: Chuck Yeung, Kimberly A. Herrmann
Rok vydání: 2002
Předmět:
Zdroj: Macromolecules. 36:229-237
ISSN: 1520-5835
0024-9297
DOI: 10.1021/ma021229x
Popis: Molecular dynamics simulations of reactive compatibilization of polymer blends are performed for a wide range of chain lengths and densities of reactive groups ρo. We directly observe the predicted diffusive growth as well as the saturation at later times. The crossover to the saturation regime is consistent with theoretical predictions. There is also a separate transition from second to first-order reaction kinetics. However, the crossover to first-order kinetics does not agree with predictions. Although a depletion layer builds up on a time scale ∝ ρo-2, we find that, for times less than the Rouse time τg, the copolymer per area is a function only of tρo3 for a wide range of ρo implying an additional crossover time scale which scales as ρo-3. The interface is unstable at later times for sufficiently large ρo. The surface tension vanishes before the interface roughens showing that the instability is initiated mainly by the vanishing surface tension. The time required for the surface tension to vanish sca...
Databáze: OpenAIRE