According to Covestro, these developments are based on the company’s extensive know-how in the use and processing of polyurethanes and polycarbonates. With its combination of high strength and low weight, composites can be put to diverse uses in a variety of applications and industries, where they even replace conventional materials such as metal and wood.
Power generation from renewable sources is a key focus of Covestro. Together with SAERTEX, Covestro says it has developed an innovative technology for manufacturing wind turbine rotor blades. The rotors are fabricated in a vacuum infusion process from a polyurethane resin and a glass fibre fabric. SAERTEX will also be exhibiting at JEC World.
“The polyurethane resin wets the glass fibres very effectively, forming a very durable, but lightweight composite,” said Dr. Andreas Hoffmann, Head of Polyurethane Composites Development at Covestro. “In view of its additional advantages over the epoxy resins used to date, our resin provides the ideal foundation for fabricating even larger and therefore more efficient wind turbines in the future.” The company recently made a prototype of a 45 meter-long spar cap for rotor blades, as shown in the video at http://youtu.be/aICshNiCs80.
Covestro says that power generation from renewable sources is likewise the motivation behind Solar Impulse, an innovative project launched by aviation pioneers Bertrand Piccard and André Borschberg. With an extremely lightweight aircraft powered only by the sun, they hope to continue and complete their flight around the globe this year. Covestro is both a project partner and an official technology partner responsible for the design and construction of the cockpit in the current aircraft. A special rigid polyurethane foam system helps to minimise cockpit weight and protect the pilots.
The automotive body of the future is lightweight, helping to save energy in traffic. Fibre-reinforced plastics have proven to be very effective in this application, as they help to reduce the weight of a vehicle while simultaneously lending it high stiffness. Covestro has developed a new technology for the construction of sandwich components that also meet consumer demands for smooth, high quality surfaces.
“Components are fabricated from continuous glass fibre mats impregnated with a thermoplastic polymer formulated from polycarbonate,” said Dr. Olaf Zöllner, Head of Polycarbonate Applications Development in Europe. “The structure of the part, with its foamed core and smooth, dense outer skin, closely resembles that of bone.”
With the acquisition of Thermoplast Composite (TCG) a year ago, Covestro has expanded both its expertise in the field of continuous fibre-reinforced composites and its position in the composites market. Covestro sees promising opportunities for polycarbonate-based, continuous fibre-reinforced composites in the IT, automotive and transportation industries, as well as in consumer goods.
Durable and lightweight structural components are also the focus of another Covestro development based on a new polyurethane matrix system from the Baydur line. Its special advantage: The carbon fibre composites can absorb three times more energy than comparable resin systems. The material provides extremely high-level occupant safety in the event of a collision.
Prominent partners in the automotive industry were involved in developing it. ThyssenKrupp used the material to manufacture prototypes at its state-of-the-art Composites Technical Center in Dresden, and they performed extremely well in material testing. Thanks to the modern high-pressure resin transfer moulding (HP-RTM) process with cycle times of just a few minutes, production of the components is very efficient.
Furthermore, Covestro is developing a new process and products for the one component production of polyurethane composites. The materials are designed for use in lightweight components and display good resistance to weathering and chemicals.
To fully exploit their ability to reinforce plastics, glass fibres are coated with sizing immediately after their manufacture. The sizing prevents the glass fibres from damaging one another during the subsequent winding step. However, the real purpose of the sizing becomes evident in glass fibre-reinforced plastic composites, where it provides a mechanical bond between the plastic matrix and the glass surface, and therefore is responsible for the strength of the composite.
Waterborne polyurethane dispersions from Covestro’s Baybond line are used as binders in glass fibre sizings for thermoplastics. They boast very good film formation, adhesion and colourfastness. In addition, they ensure high mechanical, heat and hydrolysis resistance, and are compatible with common additives. New to the product line are dispersions for fibre-reinforced plastics that have been approved for food contact applications. Covestro currently has stepped up its efforts to add products for thermoset applications to the Baybond family.
To protect fibre-reinforced plastics from a variety of environmental influences, Covestro is developing new, cost-optimised processes and products for manufacturing weather-resistant polyurethane composites. Designed for use in components in exterior applications, e.g. solar panels, the materials also display excellent resistance to UV radiation and chemicals.
Covestro are sharing a stand with the German State of North Rhine-Westphalia, in Hall 5 at Stand E60/E62.