Characteristics of MIPELON™ coating usage
Abrasion resistance, sliding properties, chemical resistance
CASECASE
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CASE03
Coating modifier (PTFE substitute)
Improved durability and sliding properties for coatings, along with matting effects
Examples of use and evaluation
Automotive components, electronic devices, sliding coatings for industrial products
Issues with current materials in the field of coating additives
PTFE is widely used for the purpose of modifying the sliding properties of coatings However, various research has shown that PFOA, a chemical substance used in the manufacturing of PTFE, may cause harm to humans. While PFOA-free PTFE products have appeared on the market, there has been a growing need for PTFE alternatives due to the trend of increasing regulations on PFOA alternatives, especially in Europe.
Solution
MIPELON™ from Mitsui Chemicals is a fine-particle ultra-high molecular weight polyethylene. By using MIPELON™ as a coating additive, the abrasion resistance and sliding properties of a coating is improved. Additionally, since MIPELON™ is a polyethylene, it boasts high safety and complies with FDA standards. MIPELON™ is characterized by its spherical particles which have a narrow size distribution. The below figure is an SEM image of MIPELON™, showing the spherical shape of the particles and highly uniform particle size distribution. MIPELON™ particles range 10 - 60 μ in diameter, which enables the use of different particle sizes based on the coating.
Abrasion resistance of coatings
Additionally, the particles themselves are very slippery making them low-friction substances compared with PTFE or nylon beads. To further test and compare the performance of MIPELON™ as a coating additive, an EPDM sheet was coated using a primer. Next, the sheet was coated with a water-based coating, to which a 10% sliding additive was added along with a dispersant, and the abrasion coefficient of the coated rubber sheet with glass was measured. The figure shows the change in the friction coefficient based on the number of reciprocations for various additives. While PTFE and PE waves demonstrates a low initial coefficient, the abrasion coefficient increases as time passes. Although PA12 does not show a significant change at 5,000 reciprocating movements, MIPELON™ PM200 always demonstrates an extremely low friction coefficient. This means that MIPELON™ improves the slipperiness of rubber greater than PTFE, PA and PE wax, and demonstrates superior durability to PE wax and PTFE.
The sliding mechanism of MIPELON™
The excellent properties of MIPELON™ as a friction-reducing additive are due to the spherical shape of MIPELON™ particles, their smooth surfaces, and the outstanding abrasion resistance of UHMW-PE materials. While minimizing the contact area with glass, the particles do not scrape off, maintaining their spherical shape. By doing so the abrasion resistance can reduce friction and improve durability. The surface of PTFE particles is rough, which makes them susceptible to wear, and the friction coefficient increases as the contact area increases due to abrasion. The below figure illustrates this action.
Matting effects of MIPELON™
In addition to abrasion resistance and improved sliding properties, MIPELON™ demonstrates a matting effect even when a small amount is added to a coating. The figure shows an acrylic coating where 10% MIPELON™ has been added to an ABS resin, and it is clear that a matting effect has been produced.
Summary
MIPELON™ can improve abrasion resistance and reduce the friction coefficient of a coating. Additionally, due to its high molecular weight and spherical particle shape, it gives coatings high durability. Moreover, MIPELON™ boasts a superior friction coefficient to other additives such as PTFE and also has a matting effect. MIPELON™, which has a wide range of functions as a sliding additive, has excellent properties that are irreplaceable as an additive for PFAS-free coatings.