Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Phase-separated microstructures in "all-acrylic" thermoplastic elastomers
Autore:
Leclere, P; Rasmont, A; Bredas, JL; Jerome, R; Aime, JP; Lazzaroni, R;
Indirizzi:
Univ Mons, Ctr Rech Sci Mat Polymeres, Serv Chim Mat Nouveaux, B-7000 Mons, Belgium Univ Mons Mons Belgium B-7000 rv Chim Mat Nouveaux, B-7000 Mons, Belgium Univ Arizona, Dept Chem, Tucson, AZ 85721 USA Univ Arizona Tucson AZ USA 85721 Arizona, Dept Chem, Tucson, AZ 85721 USA Univ Liege, Ctr Etude & Rech Macromolecules, B-4000 Liege, Belgium Univ Liege Liege Belgium B-4000 ch Macromolecules, B-4000 Liege, Belgium Univ Bordeaux 1, CPMOH, F-33405 Talence, France Univ Bordeaux 1 Talence France F-33405 1, CPMOH, F-33405 Talence, France
Titolo Testata:
MACROMOLECULAR SYMPOSIA
, volume: 167, anno: 2001,
pagine: 117 - 137
SICI:
1022-1360(200103)167:<117:PMI"TE>2.0.ZU;2-H
Fonte:
ISI
Lingua:
ENG
Soggetto:
ATOMIC-FORCE MICROSCOPY; CONTROLLED RADICAL POLYMERIZATION; DIBLOCK COPOLYMER FILMS; TAPPING-MODE; BLOCK-COPOLYMERS; ENERGY-DISSIPATION; SURFACE; MORPHOLOGY; IMAGES; NIBR2(PPH3)(2);
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
47
Recensione:
Indirizzi per estratti:
Indirizzo: Lazzaroni, R Univ Mons, Ctr Rech Sci Mat Polymeres, Serv Chim Mat Nouveaux, Pl Parc 20,B-7000 Mons, Belgium Univ Mons Pl Parc 20 Mons Belgium B-7000-7000 Mons, Belgium
Citazione:
P. Leclere et al., "Phase-separated microstructures in "all-acrylic" thermoplastic elastomers", MACRO SYMP, 167, 2001, pp. 117-137

Abstract

Atomic Force Microscopy (AFM) is used to study the phase separation process occurring in block copolymers in the solid state. Measuring simultaneously the amplitude and the phase of the oscillating cantilever in tapping-modeoperation provides the surface topography along with the cartography of microdomains with different mechanical properties. This in turn allows to characterize the organization of the various components at the surface in terms of well-defined morphologies (e.g., spheres, cylinders, or lamellae). Here this approach is applied to a series of symmetric triblock copolymers made of a central elastomeric segment polyalkylacrylate) surrounded by two thermoplastic sequences (polymethylmethacrylate). The occurrence of microphaseseparation in these materials and the resulting microscopic morphology areessential factors for determining their potential applications as a new class of thermoplastic elastomers. This paper describes how the surface morphology can be controlled by the molecular structure of the copolymers (volume ratio between the sequences, molecular weight, length of the alkyl side group) and by the experimental conditions used for the preparation of the films. The molecular structure of the chains is fully determined by the synthesis of the copolymers via living anionic polymerization while the parameters that can be modified when preparing the samples are the nature of the solvent and the thermal annealing of the films. Finally, we report on a systematic comparison between images and approach-retract curve data. We show that this experimental comparison allows the origin of the contrast that produces the image to he straightforwardly evaluated. The method provides an unambiguous quantitative measurement of the contribution of the local mechanical response to the image. We show that most of the contrast in the height and phase images is due to variations in local mechanical properties and not in topography.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 25/09/20 alle ore 00:42:32