The researchers can even adjust the hardness of the material by changing the composition of the gold. They can also replace the latex in the matrix with other plastics, such as polypropylene. Since polypropylene liquifies at some specific temperature, “plastic gold” made with it can mimic the gold melting process, yet at much lower temperatures. Furthermore, the shape of the gold nanoparticle can change the material’s colour: “nanoplatelets” produce gold’s typical shimmer, while spherical nanoparticles of gold lend the material a violet hue.
“As a general rule, our approach lets us create almost any kind of gold we choose, in line with the desired properties,” Mezzenga says.
Gold for watchmaking and electronics
Mezzenga points out that, while the plastic gold will be in particular demand in the manufacture of watches and jewellery, it is also suitable for chemical catalysis, electronics applications or radiation shielding. The researchers have applied for patents for both the process and the material.
Mezzenga’s scientists had already made a name for themselves some time ago with the lightest gold in world – gold that weighed so little it could float atop cappuccino froth. “But the material was too unstable and couldn’t be worked. This time we set ourselves the clear goal of creating a lightweight gold that can also actually be processed and used in most of the applications where gold is used today” Mezzenga says.
