A very thin, high-performance plastic film is used as a plate in a new type of heat exchanger instead of titanium, at a very significant cost savings. Radelģ R polyphenylsulfone film is thermoformed to produce plates used in an interchanger for heat-driven, liquid-desiccant air conditioners developed by AIL Research of Princeton, NJ.
"We had to develop something that would withstand temperatures up to 350F and high chloride salt solutions, yet not be too high priced," says Thomas Tonon, a senior research engineer at AIL. "Stainless steel would not work for us. We would have had to go to titanium and one sheet is more than $100. So we had to design our own." The comparable price for the PPSU sheet is about $2. About 40 sheets are required to make 20 plates.
In his research of high-heat, chemically resistant materials, Tonon discovered Radel PPSU, a high-performance plastic made by Solvay Advanced Polymers of Alpharetta, GA. He also discovered the polymer is available in very thin gauges from Ajedium Films, a 7-year-old company in Newark, DE.
Ajedium was formed to develop markets for films made from high-performance plastics, such as PPSU, polyetheretherketone (PEEK), polyimides, fluropolymers and various specialty resins and alloys.
"We had decided when we started Ajedium that the hallmark of a great high-performance film is flatness, roll conformance and gauge consistency," says Kathie Cerchio, sales development manager.
Control of molecular weight and impurities is also very important, says Shari Axelrad, global market manger for ultra polymers at Solvay Advanced Polymers.
AIL is seeking partners for various forms of air conditioning that use the PPSU plate technology, including Liquid Desiccant Direct Expansion and air/liquid and liquid/liquid plastic film heat exchangers used for carbon dioxide scrubbing from power plant emissions.