04/07/2010, Düsseldorf / Germany

 

Henkel selected as 2010 JEC Innovation Award finalist

 

New resin technology for advanced composites

In aircraft engineering, there is an ongoing trend toward lightweight construction. New manufacturing methods and products for fiber reinforced composites lead to faster and cost-efficient production processes. For its innovative benzoxazine prepreg resin and film adhesive for Airbus A380 Auxiliary Power Unit housing Henkel and its partner Toho Tenax were selected as a JEC Innovation Award finalist.

Fiber composite materials have become an integral part in modern aircraft construction. They consist mainly of carbon fibers that are bonded in a resin matrix. In the aerospace industry, these pre-impregnated fibers – or prepregs for short – serve as the primary material for a large variety of components. Specifically for the Airbus A380 Auxiliary Power Unit (APU) housing engineers from Henkel and Toho Tenax worked together to develop a new benzoxazine resin system for modern carbon prepregs with improved process characteristics while fully meet the high requirements for this challenging application.

“Here the composite material must withstand high temperature exposure and comply flame, smoke and toxicity (FST) specifications to avoid that any smoke or toxic gases can enter the passenger compartment”, says Miguel Angel Cristobal, Airbus Key Account Manager at Henkel. As Epoxy resins materials fall short in either temperature performance or flammability these parts were originally designed using bismaleimide (BMI) resins. However BMI comes at high cost, requiring long cure cycles and are susceptible to microcracking.

The new Henkel Benzoxazine Resins offer a good balance of properties, processing and cost which are not fulfilled in current materials. Compared to BMI they provide lower temperature and shorter curing time while meeting the high temperature and FST requirements. The formulation was developed for cure cycle at 180°C/3-hours. In addition to such high performance attributes as low cure shrinkage, low water absorption and improved thermal stability, Henkel Benzoxazine Resins also fulfill the customer demand for further process ease and cost savings. The innovative technology has also been applied to film adhesives which are used in the A380 APU application as well.

Henkel and Toho Tenax spent several years researching this breakthrough in resins for composite materials. “We are very proud of the new benzoxazine resin based prepregs for interior aircraft applications. We have worked hard over the last couple years to develop a product that should supply cost effective solutions for wide range of industrial needs. Additionally there are also many potential applications outside aerospace such as oil and gas extraction” says Patrice Buisson, Global Vice President of Sales and Marketing at Henkel. Selected as a finalist in the aerospace category Henkel’s innovative benzoxazine resin technology prepregged with modern carbon fiber reinforcements from Toho Tenax will be on display in the Innovation Award Area at the JEC 2010.

Henkel Benzoxazine Resins with superior process and performance
Furthermore, Henkel has developed Benzoxazine Resins for other composite processes including liquid resin infusion (LRI). Major advantages of this technology are high production rates, low manufacturing cost and design flexibility through use of fiber preforms. Henkel LRI Benzoxazine Resins can be stored at room temperature up to six months. This simplifies processing enormously and substantially reduces the amount of waste. Since refrigerated storage is no longer necessary, energy consumption in the logistic cycle is now lower. And these are not the only benefits of the new resin generation. Henkel LRI Benzoxazine Resins have the advantage that they are approved for air shipment without any special requirements.

At the JEC 2010 another Henkel partner, Airtech Advanced Materials Group, will be featuring a prepreg using Henkel Benzoxazine Resin for the manufacture of composite tools. The tools are suitable for repeated cures at 180°C while maintaining good dimensional stability and vacuum integrity. Thanks to the characteristics of the Henkel Benzoxazine Resin the prepregs are stable at ambient temperatures, and have a lower exotherm during the curing process which enables shorter cure cycles to be used for manufacture of thick tools without special precautions.

Please come and visit Henkel at booth R45. For further information please do not hesitate to contact us or visit our website at www.henkel.com/aerospace.