Size-dependent nanoscale soldering of polystyrene colloidal crystals by supercritical fluids

被引：6

作者：

Varghese, Jeena ^{[1
]}

Mohammadi, Reza ^{[2
]}

Pochylski, Mikolaj ^{[1
]}

Babacic, Visnja ^{[1
]}

Gapinski, Jacek ^{[1
]}

Vogel, Nicolas ^{[2
]}

Fytas, George ^{[3
]}

Graczykowski, Bartlomiej ^{[1
,3
]}

机构：

[1] Adam Mickiewicz Univ, Fac Phys, Uniwersytetu Poznanskiego 2, PL-61614 Poznan, Poland

[2] Friedrich Alexander Univ Erlangen Nurnberg, Inst Particle Technol, Cauerstr 4, D-91058 Erlangen, Germany

[3] Max Planck Inst Polymer Res, Ackermannweg 10, D-55128 Mainz, Germany

来源：

JOURNAL OF COLLOID AND INTERFACE SCIENCE | 2023年 / 633卷

基金：

欧洲研究理事会;

关键词：

Colloidal crystals; Polystyrene nanoparticles; Mechanical and interfacial properties; Brillouin light scattering; Supercritical fluids; FABRICATION; SEPARATION; DIFFUSION; POLYMERS; DESIGN; LAYER; FILMS;

D O I：

10.1016/j.jcis.2022.11.090

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Hypothesis: Polymer particles self-assembled into colloidal crystals have exciting applications in photon-ics, phononics, templates for nanolithography, and coatings. Cold soldering utilizing polymer plasticiza-tion by supercritical fluids enables a novel, low-cost, low-effort, chemical-free means for uniform mechanical strengthening of fragile polymer colloidal crystals at moderate temperatures. Here, we aim to elucidate the role of particle size and gas-specific response for the most efficient soldering, exploring the full potential of this method.Experiments: We investigate the elastic properties of polystyrene colloidal crystals made of nanoparticles with different diameters (143 to 830 nm) upon treatment with supercritical Ar and He at room temper-ature. By employing Brillouin light scattering, we quantify the effect of nanoparticle size on the strength-ening of interparticle contacts, evaluating the permanent change in the effective elastic modulus upon cold soldering.Findings: The relative change in the effective elastic modulus reveals nonmonotonic dependence on the particle size with the most efficient soldering for mid-sized nanoparticles (about 610 nm diameter). We attribute this behavior to the crucial role of intrinsic fabrication impurities, which reduces the nanopar-ticles' free surface exposed to plasticization by supercritical fluids. Supercritical Ar, a good solvent for polystyrene, enabled effective soldering of nanoparticles, whereas high-pressure He treatment is entirely reversible.(c) 2022 Elsevier Inc. All rights reserved.

引用

页码：314 / 322

页数：9