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

• Type: Article in International Scientific Journal
• Date: 2011

Authors

Zuzana Benkova (Author) FCUP; Borys Szefczyk (Author) Other; Natalia N D S Cordeiro (Author) FCUP

Journal

Title: Macromolecules

Vol. 44

Pages: 3639-3648

ISSN: 0024-9297

Publisher: American Chemical Society

Indexing

ISI Web of Knowledge - 18 Citations

Scopus - 20 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: 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.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10