Laur Silicone Inc. has developed a one-component, heat-cured liquid silicone rubber system it claims will ease some of the problems common with two-part silicone rubbers.
Branded simply as the ``One Part'' system, Laur Silicone introduced the new development to the system in a technical paper delivered at the International Silicone Conference by Paul Kehl, the firm's chemical engineer for technical service and development.
In his paper, Kehl said traditional two-part silicone systems need to be precisely mixed to produce consistent product, requiring pumping and mixing equipment. And once mixed, the materials have short lives that are ``inversely related to temperature.''
But Laur's One Part silicone system can be compounded in one container, eliminating the need for a controlled mixing system. He said the system is thermally stable during storage and transport, even at elevated temperatures. ``Since this material is custom mixed prior to shipping, the material is uniform throughout,'' Kehl said. ``The quality assurance testing performed on one portion of this material is representative of the entire lot of material.''
This new system is Laur Silicone's first venture into liquid silicone after spending its first 27 years in business supplying custom compounded high-consistency silicone rubber. But the company has paid attention to recent studies that predict by 2010 that business for liquid silicone applications will exceed those for HCR.
``The trend is moving toward liquid silicone,'' President Daniel Laur said during an interview along with Kehl and Vice President Charles Lenk at the conference. ``If you want to stay viable, you better go where the market goes.''
Laur said his company will provide the same service for liquid that it does for HCR-in other words, take the base material and customize it for individual applications. ``We've supplied custom materials for 27 years,'' he said. ``We've taken a lot of headaches out of material. If we can do it with high consistency, we can do it with liquid.''
The silicone supplier believes so much in its patent-pending technology that it is putting an addition on its factory in Beaverton, Mich., before selling even a single pound of material. The firm is spending an undisclosed amount to boost the size of its building about 30 percent to 15,000 square feet, and also has made a substantial investment in research and development while adding mixing and laboratory equipment.
``This technology is going to make it in the marketplace,'' Laur said. ``Paul came up with the closest to the perfect cure curve I've seen.''
Kehl said the material has been tested for six months in warehouse conditions and not lost any of its properties, while material in a two-part system typically has a shelf life of roughly 72 hours after mixing. Laur Silicone still has to test the new technology with injection molding systems, but is in the process of getting transportable machinery to take to potential customers to prove its effectiveness.
The firm will have several series of liquid silicone built for specific industries, Kehl said. The products then can be modified for indivdiual performance needs, such as specific durometers.
``The material is very flexible,'' he said. ``Wherever applications tend to go with liquid silicone, this will follow.''
Lenk said once the liquid material is put on the market Laur Silicone likely will offer it in any size from a 2-pound tube to 55-gallon drums.