You won't find a bigger fan of fluoropolymer molding than Ken Kelly.
Kelly, general manager of injection molder Performance Plastics Ltd. in Cincinnati, believes that fluoropolymer materials hold great potential in the medical-device sector. His firm has been molding the materials for that market for more than 10 years.
Kelly quite enthusiastically shared his thoughts on the subject at Plastics in Medical Devices 2011, held April 11-13 in Huron.
Fluoropolymers increasingly are being used in medical storage items, particularly in areas where health-care providers are concerned about leaching from new drugs, including those used for cancer treatment. In those applications, Kelly said, fluoropolymers can overcome adhesion, biodegradability, corrosion and humidity and provide strong chemical resistance.
Other medical items making use of fluorpolymers include inhalers and other drug-delivery systems. In drug-delivery solutions, fluoropolymers can be colored and offer excellent barrier properties and low extractables. They also can be loaded with glass fiber, aluminum flake or other fillers.
In some long-term medical storage solutions, Kelly said that fluoropolymers have been able to minimize the use of silicone, which requires secondary operations.
But to penetrate the market further, Kelly said fluoropolymers will have to overcome some challenges, including a few based on inaccurate perceptions.
At times, he explained, fluoropolymers are overlooked because they're believed to be difficult to process and to have only a limited product offering. Many molders also don't believe complex parts can be made from fluoropolymers. The materials also are expensive, with high-end fluoropolymers often costing between $15 and $40 per pound.
Kelly acknowledged that safety measures are needed when working with fluoropolymers because the materials give off a toxic and corrosive gas when molded. Specialized steel tools also are needed because of the materials' corrosive effect.
But Kelly repeated that medical molding of fluoropolymers can be done the technology is out there. As proof, he cited Performance's production of 50 million units of a single medical fluoropolymer product since 2000. Some newer fluropolymer products are being made by the firm at the rate of 10 million per year.
Kelly also disproved the notion that thin-wall molding can't be done with fluoropolymers, saying that his firm has done work with walls as thin as 0.25 millimeter.