標題: Transitions of domain ordering and domain size in a spherical-forming polystyrene-block-poly(ethylene oxide) copolymer and its composites with colloidal cadmium sulfide quantum dots
作者: Sun, YS
Jeng, US
Liang, KS
Yeh, SW
Wei, KH
材料科學與工程學系
Department of Materials Science and Engineering
關鍵字: copolymer-nanoparticle composite;microdomain;phase transition
公開日期: 8-二月-2006
摘要: With specific annealing schemes applied to a neat polystyrene-block-poly(ethylene oxide) (SE) and its composites with cadmium sulfide quantum dots (CdS QD), we have observed microdomain structures and phase transitions in the system using temperature-resolved small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). Both TEM images and SAXS results show clearly that incorporation of surfactant-tethered US QD preferentially into PEO blocks leads to increases in thermal stabilities of both bcc-packed lattice (referred as long-range order) and microdomains themselves in the sphere-forming SE/CdS composites. The bcc-packed lattice in the SE/CdS composites sustains better than that in the neat SE, during a temperature elevation to similar to 160 degrees C, at which the bcc-packed SE/CdS spheres start to transform into micelles with a short-range liquid-like order. Quantitative model analysis shows that the PEO/CdS micelles can retain their size in the SE/CdS composites up to 200 degrees C, whereas the PEO micelles shrink after the softening of the PS matrix around 100 degrees C and disassociate largely into the PS matrix of the neat SE at 160 degrees C. (c) 2005 Elsevier Ltd. All rights reserved.
URI: http://dx.doi.org/10.1016/j.polymer.2005.12.055
http://hdl.handle.net/11536/12632
ISSN: 0032-3861
DOI: 10.1016/j.polymer.2005.12.055
期刊: POLYMER
Volume: 47
Issue: 4
起始頁: 1101
結束頁: 1107
顯示於類別:期刊論文


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  1. 000235522900019.pdf