LSR 7000

By Andrew H. Dent

Manufacturer: Momentive Performance Materials

Liquid silicone rubber (LSR) has long been a niche material in the medical market due to its heat resistance (for sterilizing), its flexibility (making it suitable for applications such as valves, tubes, and implants), and the fact that it is nonreactive with most materials, including human tissue. More recently, it has taken the culinary world by storm through its use in baking trays, spatulas, and other cooking utensils. This new formulation from Momentive Performance Materials (formerly the Advanced Materials Div. of GE), is being offered as a material for lenses. It has a 95% or higher optical transmission rate, putting it up there with glass, polycarbonate, and acrylic for clarity. It's harder than most (more like a regular plastic) and can be easily and quickly molded using standard equipment, but has greater heat and chemical resistance than acrylic or polycarbonate. Additionally, it is much lighter and tougher than glass. Initial applications are likely to be automotive LED lenses, as well as some medical devices.

Andrew H. Dent is vice-president of library and materials research at Material ConneXion, a leading global platform for material innovations and solutions.