The Midland, Mich.-based silicones material supplier touted two new lines in its fluoro-liquid silicone offerings, introduced a high-consistency gray silicone rubber and showcased its new Xiameter-brand RBL 9200 Series liquid silicone rubbers. 

 

On the fluoro-liquid silicone side, Dow Corning added the Silastic FL 60-9021 F-LSR and Silastic FL 70-9201 F-LSR lines. The 60- and 70-durometer LSRs are added to the 30- and 40-durometer materials already offered in the material family. 

 

The higher durometers of the new materials will allow the firm to sell to potential applications where that hardness is required, according to Gabriel Knee, project manager for high flex fatigue lines. He spoke about Dow Corning's offerings at the expo. 

 

The 60- and 70-durometer Silastic materials offer a nontacky surface, provide excellent resistance against fuels and oils, and can be used for intricate parts, the company said. The FL 60-9201 can be used for diaphragms and membranes, while FL 70-9201 is aimed at O-ring applications. 

 

"The most demand is in aerospace and automotive, and it could be used in oil and gas—anywhere where chemical resistance is required," Knee said. 

 

Dow Corning is producing the lines at a factory in Germany. They are already on the market so the supplier can make and send samples. He said thus far only a limited number of customers have been able to sample it, but the feedback has been positive.

 

Shades of gray

The new Silastic HCM 60-1225-Gray silicone rubber is a high-performance material that Dow Corning said features fatigue resistance in extreme heat and cold. It said the material especially can be used for fabricating automotive components that need high fatigue resistance in heat and cold for extended service life. 

 

Potential applications include CVJ boots, exhaust hangers, engine mounts, steering system boots and mounts for NVH control. 

 

Knee said the flex fatigue resistance goes way beyond what Dow Corning could offer previously. Its original general purpose silicone rubbers would go about 50,000 cycles before failure. Around 15 years ago, the firm developed high-durability rubbers that would last 500,000 cycles. 

 

"This material is more in the 3 million to 4 million cycle range," he said. "It's really a step change above the current materials out there." 

 

Dow Corning developed the material with a tiered automotive supplier that Knee declined to name. It should be in parts on vehicles within a year. 

 

But the silicone supplier is looking to broaden the market for the high-consistency rubber and sell it to other customers. 

 

"We believe anywhere there's a lot of vibration, it has a lot of application there," Knee said. 

 

Increasing temperatures in automotive applications also will help expand potential applications, he added. Where organic rubbers were used before, as temperatures continue to increase those materials may become less suitable for some components. 

 

"When traditionally compared to organics, silicone rubbers didn't perform so well in flex fatigue," he said. "Now we've got a material that does handle the flex fatigue and also the temperature. So it allows another choice there as the temperature rises." 

 

The new line does cost marginally more than the organics, but Knee said the company believes that advantages it brings offset the higher price. It is produced at Dow Corning facilities in Michigan and Indiana.

 

Straight to Xiameter

Since developing its online Xiameter business model, Dow Corning normally had sold materials through this channel that were more on the commodity side of the business, keeping the Dow Corning brand where there was more differentiation in properties. 

 

But the new Xiameter RBL-9200 Series LSRs were developed specifically for the Xiameter brand, Knee said. "As time has gone by, the firm has added more technical capability within the Xiameter brand to support customers," he said. "With that there has been a few new products developed for Xiameter, and this line is one of those new products." 

 

During the International Elastomer Conference, Rick Ziebell of R.D. Abbott Co. presented a paper titled "Process Enhancement through Rheology for a new Generation of Liquid Silicone Rubber" that was co-authored by Dow Corning's Christopher Windiate. 

 

The RBL-9200 Series offers enhanced rheology, pot life and cure speed, along with lower viscosity that the firm said can help users reduce cycle times, increase throughput and raise productivity. It added that intricate mold cavities can be filled more quickly and completely, and flash/flow lines can be reduced, improving quality and cutting back waste. 

 

The LSRs are aimed at such end products as kitchenware, baby/infant care, electrical insulation, keypads, grommets, gaskets and seals. The materials are made at a Dow Corning plant in Michigan.