Evonik's Coating Additives Business Line has developed four new fumed silicas from the AEROSIL® family that are much easier to disperse with the help of an innovative process technology at the Hanau site.
The four new easy-to-disperse (E2D) products from the specialty chemicals company are suitable for rheology control in both pigmented and clear coating formulations, just like their alternatives from the standard range. The main applications are wood, plastic, automotive and general industrial coatings. AEROSIL® E 972 is more universally applicable, while the other silicas are intended for specific applications - for example AEROSIL® E 812 and AEROSIL® E 805 for clear coats for automotive OEMs and AEROSIL® E 9200 primarily for special scratch resistance.
New AEROSIL® E additives simplify complex production process
The rheological properties of both product groups are the same - with considerably simplified dispersion of the new AEROSIL® E products. To produce them, the company is already producing commercial quantities at its Hanau site and has simultaneously started construction of a new production plant for pyrogenic silica in Rheinfelden. This will significantly increase capacity in order to satisfy the high level of interest from the market.
The dispersion process for rheology additives - such as fumed silica - was previously complex and time-consuming. Paint manufacturers had to grind the silicas in a long and intensive grinding step using a bead mill so that they could be homogeneously distributed in the formulation and thus develop their full rheological potential.
However, if the formulator uses the new AEROSIL® E products, the use of an energy-intensive bead mill is no longer necessary. "We have relieved our customers of this additional work," says Maximilian Morin, Head of the Industrial & Transportation Coatings market segment. "This is because the new silicas can be dispersed in just a single grinding step using a dissolver." This proves to be a clear advantage, especially in the production of clear coats.
Subsequent control of rheological coating properties
This easier dispersibility of the additives reduces processing times, lowers energy consumption during production and reduces the amount of personnel and materials required to maintain and clean the machines. This makes processes more efficient and sustainable. Another advantage: the formulator can also add the new E2D products to the finished coating at a later stage. "This allows them to control and adjust the rheology at any time," says Maximilian Cornelius, Head of Application Technology AEROSIL®. "That is unique."
The newly developed manufacturing process should not be limited to these four new AEROSIL® E products. "Our aim is therefore to use this innovative technology to offer customers other additives that are easier to disperse in the future."
