As oil prices continue to rise, polymer manufacturers search for alternatives using plants, food waste and renewable materials such as corn, beet, sugar cane, grain husk and sweet potatoes. Biopolymers are finding increasing application in a range of diverse applications.
Soy based plastics are one such alternative. Soy-based plastics can be divided into two main segments: polyurethane using soy polyols and thermosets. As per soynewuses.org, the versatility and lower production costs make soy plastics an area primed for rapid growth. Polyurethanes using soy polyols include urethane foams, binders, coatings, adhesives and sealants. Soy polyols are proven to perform exactly like their petroleum counterparts or even better in some cases with regards to total weight, strength and durability. The versatility and cost-saving aspects of soy polyols also make it a popular alternative. A soy-based polyol is combined with isocyanate to create a polyurethane resin system. US companies manufacturing soy polyols include Dow Chemical, Cargill, BioBased Technologies, and Urethane Soy Systems. Technical developments by producers have continued to improve the property profile of the polyols, and allowed their use in a broadening array of applications. Soy-based foam developed from soy polyols is also turning up in a lot of other products: from furniture and mattresses to wind-turbine blades, wake surfboards and military drones used for target practice.
Urethane Soy Systems Company (USSC), in partnerships with South Dakota Soybean Processors, USB and the soybean checkoff, developed the patented soy-based polyol, Soyol. Since its creation, Soyol has been used in various rigid and flexible polyurethane foam applications, including as a carpet-backing agent. Another product utilizing Soyol available from USSC is SoyTherm 50, a two-component, open-celled rigid polyurethane foam insulation. SoyTherm 50 offers the benefits of being free of volatile organic compounds (VOCs), formaldehyde and asbestos along with requiring less energy to produce. BioBased Systems is using a special soy polyol called Agrol to produce soy-based spray foam insulation. The product contains no micro fibers and has a high R-value. It offers insulating benefits such as improved health conditions, increased comfort, better energy efficiency and improved durability, and it’s environmentally responsible. Agrol contains functionalities of 1.8, 2.8, 3.0 and 4.0, which can be used in a variety of applications from flexible to case and rigid foams.
Ford Motor Company has continued research into biobased foams and plastics for use in automobile body panels and interior parts. Ford and Lear Corp. have introduced a new head restraint foam with 25% of the polyol replaced with soy. About 75% of Ford's North American-built vehicles feature bio-based foam in the head restraints. The auto maker continues to other applications in which traditional foam can be converted to bio-based soy foam on vehicles, such as energy-absorption areas, steering wheels and armrests. Ford first used sustainable soybean oil-derived seating foam on the 2008 Mustang. The collaboration also generated the recent complete conversion of all Lear North American Ford seating cushion foam to Lear SoyFoam. All Ford North American built vehicles use bio-based foam in seat cushions and backs. As per ICIS, in 2010, over 2 mln vehicles in Ford’s fleet used soya-based foam, which reduces petroleum oil use by a total of 1.5 mln lb (680 tons). It plans to convert 100% of its fleet to using the biofoam in the future. Soy-based polyurethane foams on the seat cushions and seatbacks, now in production on the Ford Mustang, Expedition, F-150, Focus, Escape, Escape Hybrid, Mercury Mariner and Lincoln Navigator and Lincoln MKS. Many Toyota vehicles have soy-based seat cushions, including the Prius, Corolla, Matrix, RAV4, and Lexus RX 350. The Lexus HS 250 is packed with bio-based parts, including the luggage trim upholstery, cowl side trim, seat cushions, door scuff plate and tool box area. Toyota aims to have 20% of all plastic components in its vehicles made of bioplastics by 2015.