Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Janus micelles at the air/water interface
Autore:
Xu, H; Erhardt, R; Abetz, V; Muller, AHE; Goedel, WA;
Indirizzi:
Univ Ulm, D-89081 Ulm, Germany Univ Ulm Ulm Germany D-89081Univ Ulm, D-89081 Ulm, Germany Univ Bayreuth, Bayreuther Zentrum Kolloide & Grenzflachen, D-95440 Bayreuth, Germany Univ Bayreuth Bayreuth Germany D-95440 lachen, D-95440 Bayreuth, Germany
Titolo Testata:
LANGMUIR
fascicolo: 22, volume: 17, anno: 2001,
pagine: 6787 - 6793
SICI:
0743-7463(20011030)17:22<6787:JMATAI>2.0.ZU;2-O
Fonte:
ISI
Lingua:
ENG
Soggetto:
ABC TRIBLOCK COPOLYMER; DIBLOCK COPOLYMERS; BLOCK-COPOLYMERS; ELECTRON-MICROSCOPY; LANGMUIR FILMS; SURFACE; MORPHOLOGY; POLYSTYRENE; DENDRIMERS; POLYMERS;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
50
Recensione:
Indirizzi per estratti:
Indirizzo: Goedel, WA Univ Ulm, D-89081 Ulm, Germany Univ Ulm Ulm Germany D-89081Univ Ulm, D-89081 Ulm, Germany
Citazione:
H. Xu et al., "Janus micelles at the air/water interface", LANGMUIR, 17(22), 2001, pp. 6787-6793

Abstract

Janus micelles-asymmetric star block copolymers resulting from cross-linking of the polybutadiene middle blocks of polystyrene-block-polybutadiene-block-poly(methyl methacrylate) triblock copolymersand the corresponding non-cross-linked ABC triblock copolymer precursors form monolayers on a water surface. Analysis of the lateral pressure/area isotherms and scanning force microscopy images of monolayers spread from dilute chloroform solutions reveal a lateral structure: In monolayers of both polymers, one observes elevated nanometer-sized domains separated by flat regions. However, the monolayers made from the two copolymers differ in morphology and size of the observed domains. Janus micelle monolayers are predominantly composed of arrays of circular domains with height of 16-18 nm and diameter of 70-80 nm, whilethe monolayers of the precursor triblock copolymer are mainly composed of significantly smaller elongated domains of approximately 3 nm height, 40 mnwidth, and nonuniform length. The formation of domains and the shape of the lateral pressure/area isotherms are in accordance with the assumption that the poly(methyl methacrylate) chains spread out on the water surface, while the hydrophobic polystyrene and polybutadiene chains dewet from the water surface. Differences in domain morphology are probably due to the different chain architectures of the two polymers but may as well be influenced bythe preaggregation in the spreading solvent.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 16/07/20 alle ore 20:00:16