Polymers can fine-tune attractions between suspended nanocubes

Date:
June 19, 2020
Source:
Springer
Summary:
Researchers demonstrate a high level of control over a type of
colloid in which the suspended particles take the form of hollow,
nanoscale cubes.

This case has only previously been explored through theoretical
calculations.



FULL STORY ========================================================================== Colloids are complex mixtures in which microscopic particles of one
substance are suspended evenly throughout another. They can be prepared
in many different ways, but to achieve desirable properties in the
final mixture, researchers must maintain a delicate control over the interactions which take place between the particles. In new research
published in EPJ E, a team led by Remco Tuinier at the Eindhoven
University of Technology in the Netherlands demonstrate this level of
control for a type of colloid in which the suspended particles take the
form of hollow, nanoscale cubes -- a case which has only previously been explored through theoretical calculations.


==========================================================================
Such varieties of functional colloid can be useful in a range of
technologies, including materials which manipulate the paths of light travelling through them, as well as highly sensitive light sensors. Their intricate preparation requirements can be achieved by adding in polymers
which don't stick to the microparticles, creating zones of lower density
around them. When these zones overlap, the particles become attracted
to each other in characteristic ways.

This behaviour can be finely tuned through three different techniques:
adding polymer molecules in different concentrations; varying the size difference between particles and polymer molecules; and changing the
particle shapes.

For hollow silica nanocubes suspended in a solution containing
molecules of polystyrene, Tuinier's team measured how the scattering
of light passing through the mixture was affected by the polymer's concentration. Together with visual observations, this allowed them to
assess the stability of the mixture.

Altogether, they found that their experimental results agreed remarkably
well with previous theoretical calculations. Their conclusions provide
new insights into the diverse physics of colloidal mixtures, and could
soon allow for new advances in technologies which sense and manipulate
the flow of light.


========================================================================== Story Source: Materials provided by Springer. Note: Content may be edited
for style and length.


========================================================================== Journal Reference:
1. F. Dekker, A'. Gonza'lez Garci'a, A. P. Philipse, R. Tuinier. Phase
stability of dispersions of hollow silica nanocubes mediated by
non- adsorbing polymers. The European Physical Journal E, 2020;
43 (6) DOI: 10.1140/epje/i2020-11962-y ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2020/06/200619115711.htm

--- up 21 weeks, 3 days, 2 hours, 34 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1337:3/111)