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Press release
Coating Additives
March 4, 2019

Innovation in fumed silica process eliminates bead milling

Thanks to an innovation in the production process for AEROSIL® fumed oxides from Evonik, Business Line Coating Additives, these fumed silicas can now undergo wetting and dispersion — processes that previously had to be carried out in two separate systems (dissolver, bead mill) — in a single dissolver step. The use of these so-called “easy-to-disperse silica” (E2D) decreases processing times, cleaning times, and production losses. Moreover, omitting the milling step reduces investment and maintenance costs.

In order to test its processing characteristics, rheological effects, and optical properties within a coating system, the standard product was processed using traditional bead milling procedures, while the experimental product was processed exclusively in the dissolver. The results for viscosity, gloss, haze, and jetness (depth of color) and improvement of scratch resistance (VP RS 920) were all correct within the accuracy of measurement.

The viscosity curves at high and low shear rates were identical within the key range of rising viscosity. This showcases a key advantage of the E2D products: Because they achieve the same level of efficiency and the same optical characteristics, manufacturers do not need to adjust existing formulations, and new formulations can be created according to the same rules as earlier coatings. In addition, easy-to-disperse versions of fumed silicas are chemically identical to the corresponding AEROSIL® products. An important point to highlight here is that no additives of any kind are used in the production process, making these products just as compatible with coating systems as familiar standard products.

The experimental products that are available for sampling are VP RS 92, VP RS 82, VP RS 85 and VP RS 920 which are the E2D versions of AEROSIL® R 972, AEROSIL® R 812, AEROSIL® R 805, and AEROSIL® R 9200. AEROSIL® fumed silica is mainly used in automotive and industrial coatings to control rheological characteristics, as thixotroping agent, as anti-settling agent and to help in the prevention of rust and corrosion.

Company information

Evonik is one of the world leaders in specialty chemicals. The focus on more specialty businesses, customer-orientated innovative prowess and a trustful and performance-oriented corporate culture form the heart of Evonik’s corporate strategy. They are the lever for profitable growth and a sustained increase in the value of the company. Evonik benefits specifically from its customer proximity and leading market positions. Evonik is active in over 100 countries around the world with more than 36,000 employees. In fiscal 2017, the enterprise generated sales of €14.4 billion and an operating profit (adjusted EBITDA) of €2.36 billion.

About Resource Efficiency

The Resource Efficiency segment is led by Evonik Resource Efficiency GmbH and produces high performance materials and specialty additives for environmentally friendly as well as energy-efficient systems to the automotive, paints & coatings, adhesives, construction, and many other industries. This segment employed about 10,000 employees, and generated sales of around €5.4 billion in 2017.

Disclaimer

In so far as forecasts or expectations are expressed in this press release or where our statements concern the future, these forecasts, expectations or statements may involve known or unknown risks and uncertainties. Actual results or developments may vary, depending on changes in the operating environment. Neither Evonik Industries AG nor its group companies assume an obligation to update the forecasts, expectations or statements contained in this release.