Structure factor of blends of solvent-free nanoparticle–organic hybrid materials: density-functional theory and small angle X-ray scattering

Handle URI:
http://hdl.handle.net/10754/599766
Title:
Structure factor of blends of solvent-free nanoparticle–organic hybrid materials: density-functional theory and small angle X-ray scattering
Authors:
Yu, Hsiu-Yu; Srivastava, Samanvaya; Archer, Lynden A.; Koch, Donald L.
Abstract:
© the Partner Organisations 2014. We investigate the static structure factor S(q) of solvent-free nanoparticle-organic hybrid materials consisting of silica nanocores and space-filling polyethylene glycol coronas using a density-functional theory and small angle X-ray scattering measurements. The theory considers a bidisperse suspension of hard spheres with different radii and tethered bead-spring oligomers with different grafting densities to approximate the polydispersity effects in experiments. The experimental systems studied include pure samples with different silica core volume fractions and the associated mean corona grafting densities, and blends with different mixing ratios of the pure samples, in order to introduce varying polydispersity of corona grafting density. Our scattering experiments and theory show that, compared to the hard-sphere suspension with the same core volume fraction, S(q) for pure samples exhibit both substantially smaller values at small q and stronger particle correlations corresponding to a larger effective hard core at large q, indicating that the tethered incompressible oligomers enforce a more uniform particle distribution, and the densely grafted brush gives rise to an additional exclusionary effect between the nanoparticles. According to the theory, polydispersity in the oligomer grafting density controls the deviation of S(q) from the monodisperse system at smaller q, and the interplay of the enhanced effective core size and the entropic attraction among the particles is responsible for complex variations in the particle correlations at larger q. The successful comparison between the predictions and the measurements for the blends further suggests that S(q) can be used to assess the uniformity of grafting density in polymer-grafted nanoparticle materials. This journal is
Citation:
Yu H-Y, Srivastava S, Archer LA, Koch DL (2014) Structure factor of blends of solvent-free nanoparticle–organic hybrid materials: density-functional theory and small angle X-ray scattering. Soft Matter 10: 9120–9135. Available: http://dx.doi.org/10.1039/c4sm01722f.
Publisher:
Royal Society of Chemistry (RSC)
Journal:
Soft Matter
KAUST Grant Number:
KUS-C1-018-02
Issue Date:
15-Sep-2014
DOI:
10.1039/c4sm01722f
PubMed ID:
25311668
Type:
Article
ISSN:
1744-683X; 1744-6848
Sponsors:
This work was supported by Award no. KUS-C1-018-02 made by King Abdullah University of Science and Technology (KAUST).
Appears in Collections:
Publications Acknowledging KAUST Support

Full metadata record

DC FieldValue Language
dc.contributor.authorYu, Hsiu-Yuen
dc.contributor.authorSrivastava, Samanvayaen
dc.contributor.authorArcher, Lynden A.en
dc.contributor.authorKoch, Donald L.en
dc.date.accessioned2016-02-28T06:09:18Zen
dc.date.available2016-02-28T06:09:18Zen
dc.date.issued2014-09-15en
dc.identifier.citationYu H-Y, Srivastava S, Archer LA, Koch DL (2014) Structure factor of blends of solvent-free nanoparticle–organic hybrid materials: density-functional theory and small angle X-ray scattering. Soft Matter 10: 9120–9135. Available: http://dx.doi.org/10.1039/c4sm01722f.en
dc.identifier.issn1744-683Xen
dc.identifier.issn1744-6848en
dc.identifier.pmid25311668en
dc.identifier.doi10.1039/c4sm01722fen
dc.identifier.urihttp://hdl.handle.net/10754/599766en
dc.description.abstract© the Partner Organisations 2014. We investigate the static structure factor S(q) of solvent-free nanoparticle-organic hybrid materials consisting of silica nanocores and space-filling polyethylene glycol coronas using a density-functional theory and small angle X-ray scattering measurements. The theory considers a bidisperse suspension of hard spheres with different radii and tethered bead-spring oligomers with different grafting densities to approximate the polydispersity effects in experiments. The experimental systems studied include pure samples with different silica core volume fractions and the associated mean corona grafting densities, and blends with different mixing ratios of the pure samples, in order to introduce varying polydispersity of corona grafting density. Our scattering experiments and theory show that, compared to the hard-sphere suspension with the same core volume fraction, S(q) for pure samples exhibit both substantially smaller values at small q and stronger particle correlations corresponding to a larger effective hard core at large q, indicating that the tethered incompressible oligomers enforce a more uniform particle distribution, and the densely grafted brush gives rise to an additional exclusionary effect between the nanoparticles. According to the theory, polydispersity in the oligomer grafting density controls the deviation of S(q) from the monodisperse system at smaller q, and the interplay of the enhanced effective core size and the entropic attraction among the particles is responsible for complex variations in the particle correlations at larger q. The successful comparison between the predictions and the measurements for the blends further suggests that S(q) can be used to assess the uniformity of grafting density in polymer-grafted nanoparticle materials. This journal isen
dc.description.sponsorshipThis work was supported by Award no. KUS-C1-018-02 made by King Abdullah University of Science and Technology (KAUST).en
dc.publisherRoyal Society of Chemistry (RSC)en
dc.titleStructure factor of blends of solvent-free nanoparticle–organic hybrid materials: density-functional theory and small angle X-ray scatteringen
dc.typeArticleen
dc.identifier.journalSoft Matteren
dc.contributor.institutionCornell University, Ithaca, United Statesen
kaust.grant.numberKUS-C1-018-02en
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