Silphon® PUR circular-structure foam

Silphon® acoustic circular-structure foam is a polyurethane flexible foam with an open-cell structure, complemented by a characteristic circular-profiled surface. This structure significantly increases the effective surface area and causes incident sound waves to be scattered, refracted and absorbed multiple times within the material’s open cell channels. Whilst conventional flat foams are primarily effective in higher frequency ranges, the circular structure of the material also demonstrates significantly improved attenuation in the mid and lower frequency ranges. This makes the circular-structured foam particularly suitable for technical applications with complex noise spectra.

The material is based on polyether PUR foam with a medium density (typically approx. 25–30 kg/m³). The material remains dimensionally stable yet flexible, allowing it to be easily processed, cut to size and adapted to different geometries. Thanks to its open-cell structure, it has high air permeability, which is crucial for the absorption of airborne sound.

A key feature is the sealed circular-structure surface. This provides the foam with additional protection against mechanical abrasion and moisture without compromising its acoustic performance. This makes the circular-structure foam suitable even for harsh industrial environments where untreated foams might age more quickly or be compromised by dust and dirt.

For quick and efficient installation, the foam can be fitted with a high-quality self-adhesive layer on the reverse side. This enables permanent attachment to smooth and clean surfaces without the need for additional tools. The material is therefore also suitable for large-scale installations where simple and time-saving installation is required.

Typical applications are found in mechanical and plant engineering, particularly in enclosures for compressors, power units and motors, where it effectively reduces operating noise. The circular-structured foam also demonstrates its advantages in ventilation and air-conditioning systems or in industrial silencers, as its structured surface provides broadband sound absorption whilst also being mechanically robust. In technical rooms, test benches or enclosures, it ensures a significant reduction in noise levels, thereby improving not only working conditions but also protecting the surrounding environment from disruptive noise.