Thermoplastic catamaran highlights plastic waste recycling
This month, adventurer David de Rothschild and a crew that will include several scientists will set sail on a 60-ft/18.5m catamaran, dubbed Plastiki, made entirely of postconsumer plastic bottles in various forms. The founder of Adventure Ecology, a group dedicated to calling attention to human impacts on remote ecosystems, de Rothschild is, with this voyage, showing how waste materials can be reused. The vessel, named to evoke the 1947 Thor Heyerdahl Kon-Tiki expedition, will sail from San Francisco, Calif. to Sydney, Australia, via a number of ecologically threatened areas, says the group.
Plastiki was engineered to incorporate recycled polyethylene terephthalate (PET) as structural composite elements, says Mike O’Reilly of Level 2 Industries (San Francisco), who helped develop the manufacturing methods. The hull panels, bulkheads, crosshull beams and other components are sandwich constructions of PET fiber-reinforced PET skins developed by Comfil (Gjern, Denmark) over T90 PET structural foam (Alcan Airex AG, Sins, Switzerland). The parts, each with unique skin layup schedules depending on anticipated loads, were vacuum bagged and compression molded at 415°F/214°C. As many as 16,000 2-liter plastic bottles were lashed together to fill the open twin-hull structure for buoyancy. O’Reilly reports that the team developed an epoxy resin from sugar and cashews for boat sections in which thermoplastic adhesives couldn’t be used: “The project showcases high-tech, innovative materials and technologies that, when smartly designed, can produce high-quality products while keeping environmental impact to a minimum.”
Plastiki’s progress can be followed at the Adventure Ecology Web site: www.adventureecology.com/theplastiki/.
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