Perfect Particles Make 3D Structurally Coloured Objects

The particle theory of matter sits at the centre of the scientific methodology. Objects that appear uniform, solid and homogeneous at the everyday macroscopic scale are, when you investigate them with sufficient resolution and detail, in fact made up of particles (atoms, molecules and compounds) that are not the same entity as the object they form.

The particle theory explains several observable properties of matter, including its density, its ability to expand and contract in response to changes in temperature and applied force, and its behaviour when it undergoes phase changes such as melting or boiling. An assumption of the theory is that all of the particles in a material are perfectly spherical and of identical size. In their research at Saarland University (Germany) Professor of Polymer Chemistry Markus Gallei and his doctoral student Lukas Siegwardt set out to create ‘perfect particles’ with a hard centre and a soft shell to build 3D structurally coloured objects.