Effect of nanoclay incorporation on the mechanical properties and water damage resistance of composites materials

ROMINA OLLIER; GASTÓN FRANCUCCI; EXEQUIEL RODRIGUEZ; VERA ALVAREZ

San Sebastían

Simposio; 11th European Symposium on Polymer Blends; 2012

Universidad del País Vazco

Nowadays, the development of sustainable energies is one of the most important engineering challenges. The use of wind turbines has grown significantly in the last years because they produce clean energy from a free and renewable resource, reducing fossil fuel consumption and contaminant gasses emission. The blades are the most important component of the wind turbines and they are manufactured under strict aero dynamical and mechanical requirements, including low weight, high stiffness, high strength and resistance to corrosion and fatigue. They are currently made with composite materials (mainly a thermosetting polymer matrix reinforced with glass fibers) because they meet the mentioned requirements and they can be processed to produce the finished part by simple and inexpensive manufacturing methods such as vacuum infusion. Wind blades are frequently exposed to severe environmental conditions such as high relative humidity or rainy weather. These conditions might cause water absorption of the composite material affecting the mechanical properties of the component. Nano-reinforcements are currently being used to improve the mechanical properties of composite materials. Layered silicates are widely used as nano reinforcements of polymeric materials. Bentonite is a type of clay that presents some advantages over other layered silicate [3]. The dispersion of the bentonite and the exfoliation of its structure are crucial to obtain the optimal mechanical properties. In this work, the effect of the environmental humidity and the mechanical properties of composite materials used in the manufacture of wind blades were studied. As the dispersion of the nanoparticles in the matrix was insufficient and therefore no benefits were observed with respect to the original composites, a chemical modification was performed by exchanging the inorganic cations of the bentonite with alkylphosphonium cations, in order to improve their compatibility with the polymer and thus, its dispersion degree. The mechanical properties, water absorption behavior and the degradation of the properties caused by water sorption were studied.