Hoffmann's reinforcement for silicone adds advantages

By David Shaw, ERJ staff

Nuremberg, Germany - Reception for Hoffmann Mineral's latest silicone reinforcing filler was very positive, according to Dr Alexander Risch, sales and marketing director, speaking at the end of the IRC event in Nuremberg.

The company has created a filler designed specifically for silicone rubbers which offers significantly better processing performance, improved vulcanisate properties and more competitive prices than more traditional fillers such as quartz flour and/or diatomaceous earth.

The product - Aktisil Q - is a modified version of the company's Neuburg Siliceous Earth (NSE). It has silane surface treatment, which interacts strongly with the polymer. In the vulcanisate, this strong rubber-filler interaction effectively extends the cure in the material, which in turn leads to better compression set performance, even without post-cure treatment. Also, compounds made with the material offer markedly improved oil resistance.

A key benefit of the product is the improved processing - especially in extrusion. Where quartz is abrasive, NSE is much softer, leading to reduced wear on process equipment. A further benefit is the improved green strength of the unvulcanised compound. This means tubes or profiles made using the new additive have substantially improved collapse resistance.

Risch said the company noticed a downturn toward the end of 2008 and immediately made some significant decisions to overcome the situation. One of these was to address the silicone rubber market with a new product. The company researched the requirements and found a good combination of products from the various quarries it operates. Once a suitable surface treatment had been identified, the product could be launched. From idea to initial launch took around eighteen months, noted Hubert Oggermueller, head of application technology.

This is an external link and should open in a new window. If the window does not appear, please check your pop-up blocking software. ERJ is not responsible for the content of external sites.

technical presentation from Hoffmann Mineral