Through collaboration with leading manufacturers of window profiles, Styrolution, the global leader in styrenics, endeavoured to jointly develop a new generation of window frame profiles, which addressed legal requirements for energy consumption while advancing window profile technology.
New generation of window frame profiles (photo: shutterstock)
Large window frames often contain a steel core to stabilise the frame. However, steel has a high thermal conductivity, leading to unnecessary energy loss. With the European Union setting the goal of reducing greenhouse gas emissions and energy consumption by 20% by 2020, the ENEV, the energy saving regulations of the German Federal Government, have outlined steps for the achievement of this goal. Included in these steps are indicative targets for the thermal conductivity of glass, which should not exceed a value of U of 0.8W/m²K, even in private homes.
A window with a conventional frame width of approximately 82mm provides a value of about U = 1.0W/m²K. Thus, the new window profile had to reduce the thermal conductivity of the window frame by approximately 20% – while maintaining framework strength. Traditionally a steel beam with high thermal conductivity was inserted into plastic window frames for added strength. As such, the task for Styrolution was to develop a material that replaced the steel core, without compromising the stability of the frame.
Lower energy consumption with high stability
Luran 378P G10, a special polymer compound from Styrolution, is said to meet all of the outlined energy requirements. Compared to steel, Luran, the core material of the frame, is said to provide high strength values along with high production efficiency and reduced thermal conductivity, says the company.
The Luran core is co-extruded with the window frame. Compositing the core with the frame material provides very good load bearing capacity, even for narrow window profiles. During window installation the core is welded directly in the corners by the window manufacturer. This solid welding composite guarantees additional stiffness, strength and stability.
For optimal cohesive composite, it is important that the plastic material is compatible with PVC. Luran and its grade 378P G10 are compatible and at the same time also guarantee good processing. Styrolution claims that Luran is also cost-effective when compared to steel due to its production costs.
www.styrolution.com
