Fraunhofer IVV develops stable bio-wax dispersions
Plants form thin layers of wax to protect themselves from drying out. This natural, renewable raw material has hardly been used so far. In the future, however, it can be considered more strongly as a form of sustainable coating. It can be used to coat the surfaces of films and paper webs in order to achieve a water vapour barrier and additionally make them water-repellent. In order for these dispersions to be processed in industrial plants, they must be stabilised. For Candelilla wax, this has already been demonstrated in the Fraunhofer IVV. The institute has also developed the associated processes.
Wax dispersions suitable for industrial processes
Finely distributed particles were formed from the wax by melt emulsification. Various emulsifiers available on the market were used to stabilise the waxes. An emulsifier mixture of Tween 20 and Span 20 resulted in more stable dispersions than a mixture of Tween 80 and Span 80. No agglomeration and coalescence was observed for a storage period of 21 days. The wax dispersions were stabilised in such a way that they are suitable for industrial processes. The results and methods are also used for the stabilisation of other wax dispersions and are available for industrial applications.
The study is published in: Coatings 2018, Vol. 8, Issue 12, p. 469.