I thought there might be some interesting chemistry involved in Moon Dough, set to be the one of the toy industry’s biggest sellers this Christmas. According to the manufacturer, it’s a ‘magical molding dough’ that never dries out.
A good start: the pleasant people at Spin Master were kind enough to send me a sample to play with. Thus, I can confirm that it is rather good fun – at least it was for the ten minutes or so that I spent fashioning abstract expressionist artworks. But my inexpert inspection didn’t help with determining the composition. And unfortunately the Spin Master people were less helpful on that front. They declined my offer of an interview on the grounds that they didn’t want to compromise the ‘secret recipe’ and when I asked for the patent number they didn’t reply.
But they did furnish me with an information sheet, which reassures everyone that Moon Dough is ‘completely non-toxic’, wheat-free and hypoallergenic. In addition, it lists 25 substances – mostly foodstuffs – that Moon Dough does not contain, including bizarrely crustaceans (a reference perhaps to chitosan, a polysaccharide derived from shrimp exoskeletons).
Entertaining stuff – but not much use really. Pushing my finely-honed journalistic skills to the limits, I interrogated the packaging, which revealed the dough is made by a company called Delta of Sweden. My requests for an interview went unanswered. But the name led me to a patent application that seems to cover if not the very same technology in Moon Dough something very similar.
It describes a material comprising hard particles coated in a hydroxyl-terminated polymer, such as silicon oil, with a boron-containing compound to provide cross-linking, which increases viscosity – the inventors suggest boronic acid. This brings to mind silly putty, which at its discovery in 1943 was a simple mix of silicone oil and boric acid. (In contrast, Play-Doh is a water-based mixture.) And the chemistry therefore would be pretty simple. Water is removed and voila: the material doesn’t dry out because there isn’t any water in it.
In fact, water is likely to mess things up a bit by sending the reaction in reverse. In addition, the lack of water, the authors note, should help to keep bacteria at bay, a benefit during play groups and the such like, when the material is likely to be passed from one child to the next.
Is this the stuff in Moon Dough? Without some further input from the companies, I’m not going to know – so I’ll open the floor to other guesses (sensible or otherwise).