With the introduction of its “LNP Colorcomp WQ117945” compound, a material based on advanced nanotechnology, Sabic can successfully enhance both the performance and the sustainability of today’s PET foams. The new compound not only facilitates the efficient production of PET foams for core materials in sandwich structures, when used to produce, for example, wind turbine blades, it offers a strong, lightweight, recyclable option over incumbent materials, such as balsa wood and PVC foam.
The new compound improves control over nucleation and cell growth, resulting in decreased cell size and uniform, narrower cell size distribution. These attributes can reduce the foam’s weight by minimising resin uptake in sandwich structures, the company said. It can also potentially improve shear strength/strain properties for better fatigue performance.
The compound is said to provide benefits to multiple industries, including marine, building and construction, packaging and wind energy - in applications ranging from ‘building insulation and cladding, to boat hulls and decks, to the core of wind turbine blades’ claimed Sunamita Anunciação, LNP Business Development Manager for Sabic. Not only can high-density PET foams can potentially compete with balsa wood while avoiding wood’s natural variations, as thermoformable polymers, PET foams offer greater freedom in the design and shaping of wind blades.They also offer stable supply, cost-effectiveness, consistent material properties and much less resin uptake.
“In addition to improving PET foam’s mechanical properties, our technology helps reduce weight, which opens new opportunities for sustainability,” Anunciação pointed out.
Weight reduction is a key issue in wind blade design. Lighter foam core materials can allow designers to create longer, more-efficient wind blades. Extending blade length to increase the amount of captured energy normally adds significant weight to the blade. This compound can reduce foam cell size by as much as three times compared to standard nucleating agents such as talc, while decreasing cell size disparity by a factor of up to five. These factors help to reduce resin uptake by the foam during composite manufacture, resulting in a lighter-weight blade.
Another global concern is the end-of-life: what happens to these blades when they are discarded?
“Due to their huge size and complexity, most blades are currently sent to landfills to be disposed of,” the company said. Using PET means these will now instead be able to be recycled.
Moreover, besides being used as an effective nucleating agent for foaming processes, Sabic said the nanotechnology solution can also act as a rheological modifier for improving melt strength and thermoformability. The nanotechnology can be adapted for other resins besides PET.