PITTSBURGH—The first commercialized product from the PPG Industries Inc. Agilon performance silicas platform launched earlier this year is receiving positive feedback from its tire industry customers, according to a company official.
The Agilon product line—in development the past couple of years—is a chemically modified precipitated silica that the company claimed both enhances the performance of the product and eliminates drawbacks associated with the traditional highly dispersible silica filler.
The first product in the platform is the Agilon 400, which is in various late-stage developments with multiple tire manufacturing customers, said Tim Okel, PPG senior research associate for silica products.
“It was mostly developed because of response from tire customers,” he said. “They were looking for further improvements in performance and to get over some of the processing challenges from the current silica/silane technology.”
Agilon 400 silica is designed to help tire makers overcome a variety of production limitations by eliminating the need for a silane coupling agent, increasing mixing efficiency and reducing volatile organic compound emissions.
On the mixing side, the highly dispersed silicas with silane that were first used in the early 1990s and have been key in improving traction and reducing rolling resistance cause several problems in this area, Okel said.
He said the silica traditionally is blended with the silane at the customer's plant in a mixer not designed for the activity. The mixers aren't meant to do the chemical reaction required, so tire producers have to run multiple passes to get the process right, resulting in reduced productivity.
With Agilon, the silica and silane mixing step is moved upstream into PPG's manufacturing process, allowing tire makers to run mixers faster and more efficiently, Okel said. PPG claims the Agilon technology reduces mixing time by 36 percent and allows an 18- to 27-percent increase in batch size.
With respect to VOC emissions, most of the silanes used in the current technology are alkoxy-based, which gives off alcohol. He said this causes tire manufacturers to use regenerative thermal oxidizers to capture alcohol that burns off, a step not required with PPG's Agilon product.
Customers also told PPG that they were only able to capture about half of the alcohol that is emitted, with the rest vented to the atmosphere, which required manufacturers to obtain permits to cover the activity.
Okel said the alcohol also created some performance issues, such as causing blisters in the extruded rubber, causing tire makers to run extruders at a slower rate, again impacting productivity. “Agilon has no alcohol, so it eliminates all the issues involved with that,” he said.
Rubber compounds made with the current silica/silane package also can undergo an increase in viscosity if the material sits too long before being compounded, according to Okel, sometimes leading to scrapped batches. “With the number of advantages we're looking at, it basically boils down to the (compound) moving through the factory and to the presses into the final tire more easily,” he said.
On top of the gains in manufacturing, Agilon also is being found to bring better performance as well, Okel said. PPG predicts about 30-percent more reduction in rolling resistance, which would translate to roughly a 6-percent increase in fuel efficiency. “That about doubles the improvements of current technologies,” he said.
Concurrently, that boost in rolling resistance comes with no worse than a maintenance of current traction performance and, in some cases, slight improvement.
The company also expects a 10-percent improvement in abrasion resistance based on lab tests, leading to better treadwear as well.
Some customers' own test numbers basically confirm the trends that PPG forecast with its tests, Okel said, although he couldn't share that data.
The Pittsburgh-based company sees big potential for its new silica platform. “This is a unique technology,” he said. “It is covered by a number of national and international patents. There is no match to the material at this point that we are aware of.”
While tires were the initial focus for Agilon, PPG also is looking at other areas. In fact, the firm has made one sale into the industrial rubber market for a version of Agilon, though Okel couldn't reveal what the application was for.
He did say that in general PPG will be looking at potential uses in belts, hoses, under-the-hood automotive products and some housing-type applications. Okel said PPG hasn't yet determined when it will release an Agilon grade aimed at the industrial rubber market.