Mitsui Chemicals: PTFE alternative Mipelon UHMW-PE fine powder

The limiting factor in the substitution of PTFE is the lower melting temperature of UHMW-PE, which is around 135 °C. While Mipelon can generally be used at temperatures of up to 120 °C, the special grade PM200C is suitable as an additive in hydrocarbon oil for temperatures of up to 200 °C. Unlike PE powder, it does not tend to swell at higher temperatures. Unlike PE powder, it does not tend to swell even at higher temperatures and retains its shape and function. In addition, it is characterized by improved dispersing behavior in the plastic masterbatch. In many cases, the same dosage results in a lower coefficient of sliding friction and improved abrasion resistance than with PTFE, which enables economical use. In addition, the density of 0.97 g/cm³, which is about half as high, helps to reduce weight. Mitsui Chemicals Europe sells Mipelon directly and through its distributor Dreyplas, which also supports customer-specific new and further developments.

Fine powder Mipelon grades ideal for paints and coatings

Mipelon, which has a molecular weight of around 2 million g/mol, is characterized by the very small size of its special spherical particles. The average particle size (D50) for the PM-200 type is around 10 µm, which is currently the smallest size in the world for this product group. For the XM-220 type, the D50 value is around 30 µm and for the XM-330 type it is 65 µm. The larger particles are used for the modification of rubbers and plastic compounds and as filters. In contrast, the finer powder types are ideal for paints and coatings. Mitsui Chemicals Inc. in Japan is currently developing powder types with a D50 value of less than 5 µm and around 6 µm. The latter is already available as a sample. Commercial availability is planned for the end of 2025. In general, the spherical particles with their smooth surface and narrow particle size distribution support very good dispersion. The particle size distribution of Mipelon is significantly narrower than that of PTFE, and it also has a significantly lower proportion of large particles. In addition, the material exhibits lower sliding friction and abrasion values under long-term stress not only compared to PTFE but also compared to PA11 and PA12 as well as PE waxes.

Wide range of applications such as surface coatings

Mipelon is also characterized by its high chemical resistance to acids, alkalis and organic chemicals. In addition, it absorbs virtually no water or moisture. Most types are suitable for food contact applications in accordance with EU and US legislation. Due to this wide range of properties, typical applications range from chemically resistant surface coatings, including electrostatic powder coatings, water- or solvent-based spray coatings and dip coatings, to the additivation of rubber and thermoplastics. Examples of applications include rubber-coated rollers, coatings for rubber profiles for the automotive industry, plastic compounds, anti-blocking for films instead of zeolites and silicon, oils and greases with emergency lubrication. Together with customers, Dreyplas and Mitsui Chemicals Europe are developing solutions to replace PTFE with UHMW-PE and to optimize tribological properties. This also includes the use of Lubmer UHMW-PE, which is available in granulate form and has been developed by Mitsui Chemicals for extrusion and injection molding applications.