The microspheres consist of a polymeric shell filled with a physical blowing agent. When exceeding the so-called starting temperature (T Start) during processing, the shell softens, and the blowing agent starts to inflate the shell. Thus, depending on UNICELL MS grade and processing conditions, an expansion rate of up to 50 times can be achieved. If the maximum processing temperature (T Max) is exceeded, particles may shrink or collapse.

When processed adequately, the microsphere particles will keep their shape and just significantly increase their volume, allowing to create a very uniform, closed cell and light structure, which cannot be achieved in many polymers by other foaming technologies.

Expandable microspheres are the material of choice to foam particularly e.g. soft polymers or polymers with a low melt strength such as plastisols, Thermoplastic Elastomers (TPE), Thermoplastic Polyurethane (TPU) or Silicones. UNICELL MS products can also be used to achieve specific surface or haptic effects (e.g. mattening of vinyl wallcovering).

UNICELL MS grades are available as dry, unexpanded powders but also in masterbatch form for improved handling and processing of thermoplastics and elastomers. Wet, unexpanded grades are suitable for use e.g. in dispersions or composites. Typical applications of UNICELL MS grades are e.g. vinyl wallcoverings, PU coatings, textile printing, Automotive Under Body Coatings or shoe soles.

The product portfolio comprises microspheres with starting temperature ranging from 90 to 190°C and medium particle sizes from 7.5 to 50 µm, covering a wide range of applications.

Apart from expandable microspheres UNICELL MS TRAMACO also offers UNICELL HMS pre-expanded microspheres with densities ranging from 0.017 up to 0.165 kg/m³ as ultra-lightweight filler materials. UNICELL HMS products are available both as dry types and water-containing wet types.

All UNICELL MS and UNICELL HMS grades are REACH compliant and chlorine-free.