Molecular Dynamics Study of Hydrated Poly(ethylene oxide) Chains Grafted on Siloxane Surface

• Tipo: Artigo em Revista Científica Internacional
• Data: 2011

Autores

Zuzana Benkova (Autor) FCUP; Borys Szefczyk (Autor) Outra; Natalia N D S Cordeiro (Autor) FCUP

Revista

Título: Macromolecules

Vol. 44

Páginas: 3639-3648

ISSN: 0024-9297

Editora: American Chemical Society

Indexação

ISI Web of Knowledge - 16 Citações

Scopus - 16 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Química

Outras Informações

ID Authenticus: P-002-RH0

DOI: 10.1021/ma200233g

Abstract (EN): In this work, hydrated poly(ethylene oxide) (PEO) chains composed of varying length N irreversibly grafted to an amorphous siloxane surface by one chain end at different coverage densities sigma were studied using atomistic molecular dynamics simulations. We have assessed beginning of the extended overlapping chains (brush regime) at sigma = 0.437 nm(-2) and identified the mushroom-like conformation of nonoverlapping chains. For the studied systems, the specific interactions lead to density distributions different from the functions analytically derived for model systems. The brush regime demonstrates itself in the density distribution functions and the reduced height h/N evolution with sigma. Since the latter dependence indicates h similar to N sigma(1/2) scaling, the brush regime corresponds to the situation of a concentrated aqueous PEO solution with a correlation length sigma(-1/2). The extrapolated thickness of PEO brushes reproduces experimental results fairly well. Water molecules prevent EO monomers from an adsorption to the siloxane surface.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 10