CASECASE

Characteristics of LUBMER^™ engineering plastic modifiers

Abrasion resistance, sliding properties, quietness, maintenance of mechanical properties of resin

Examples of use and evaluation

Automotive components, elevator and escalator mechanical components, cable components, sliding components in electronic devices

Issues with current materials used in the field of engineering plastics

Engineering plastics are increasingly being used in place of metal components. However, when a plastic is used on movable components, sliding properties and abrasion resistance can be problematic. That is why issues are often resolved by combining resins with additives. Generally, while PTFE is used in many cases, recently in Europe in particular there have been increased regulations on PFOA and substitute substances used in the manufacturing of PTFE, resulting in a need for alternatives.

Solution

Ultra-high molecular weight PE has an extremely high molecular weight and boasts the highest impact strength among the thermoplastics currently being manufactured. Additionally, ultra-high molecular weight PE has characteristically low friction, high abrasion resistance as well as extremely high chemical resistance. Among them, LUBMER^™ LY1040 can be used as a sliding property modifier of engineering plastics on various materials including polyamide (PA6), polyacetal (POM), polybutylene terephthalate (PBT), polycarbonate (PC), polyphenylene sulfide (PPS) and acrylonitrile butadiene styrene (ABS). The figure below shows the measured friction coefficient and specific wear amount when LUBMER^™ and PTFE were added to various engineering plastic resins. By increasing the amount added, the friction coefficient and specific wear amount can be lowered.

Effects of sliding property modification compared with other additives

The friction coefficient and relative abrasion quantity when LY1040, PTFE and molybdenum disulfide were actually added to PA6 resin was measured. PA6 pallets and LY1040 pellets were pelletized at 240°C cylinder temperature in a two-axis extrusion machine. Various resins were injection molded into test pieces, and ring abrasion tests were performed using S45C steel as the opposing material. The top left shows the friction coefficient, and the bottom right shows the relative abrasion quantity. As the diagram shows, even with a small quantity added, the sliding properties and abrasion resistance can be improved significantly compared with the substrate on its own, or the substrate with PTFE or molybdenum disulfide added.

The attached image shows actual test pieces after the ring abrasion tests were performed, and it is evident that abrasion has not occurred with the test piece to which LUBMER^™ was added.

Quietness effects from adding LUBMER^™ LY1040

Additionally, as sliding properties can be enhanced by adding LUBMER^™ LY1040, it is also possible to improve quietness. The diagram shows the measured decibels generated when gears rub against one another under the following conditions. As this shows, adding LY1040 reduces decibels by 3dB. It also has a lower decibel value compared to PTFE. This effect represents an extremely effective property for products such as the sliding components for automotive applications, where the requirements for quietness are even greater with the spread of electric vehicles.

Applications for actual use

LUBMER^™ LY1040 is effective as an abrasion-reducing additive for a wide range of applications including automotive, electronic devices, construction materials and home appliance components. It can also achieve noiseless operation in various devices that include plastic moving parts. Specific examples include bearings for film developing and processing machines, bearings for vending machines, gear parts for air purifiers and automotive components. LUBMER^™ also has a density of less than 1g / cm3, roughly half the specific gravity of PTFE, a typical additive. This makes it ideal for use in lightweight components with enhanced durability.

Summary

When LUBMER^™ LY1040 is used as an additive, it demonstrates superior sliding properties to PTFE or molybdenum disulfide even when a small amount is added.  Additionally, the wear resistance of PA6 and many other materials can be greatly improved. Because of this, it is an extremely excellent product as a PFAS-free engineering plastic modifier.