Electrolube’s Polyurethane Resin A Success for Tier 1 Automotive Supplier

The automotive customer found an ideal production partner in Electrolube, whose UR5608 tough polyurethane potting and encapsulation compound proved the best solution for protecting their on-board charger.

The automotive supplier was originally looking for a thermal management material to fill air gaps, and dissipate heat, between the PCB and cooling channels in their on-board charger. They believed that that they needed a material with a thermal conductivity in the region of 4-6 W/m.K. After further discussion to understand the application in more detail, Electrolube determined that the automotive customer had hot spots on their PCB when a thermal management material was used. This was caused by the high viscosity of these products and the very small gaps in the on-board charger that the material needed to flow into, which left air pockets remaining after filling. Air is a poor conductor of heat, approx. 0.025 W/m.K, and therefore the remaining air pockets reduced the efficiency of heat transfer.

Electrolube proposed looking at a thermally conductive resin with lower viscosity and better flow properties, to be able to fill even the smallest gaps in the unit more effectively. Furthermore, the customer also needed high dielectric strength, excellent protection to automotive fluids and support against vibration, whilst also offering flexibility for fragile components during thermal shock. These specific requirements led Electrolube to suggesting the versatile UR5608 polyurethane resin that provides excellent flow even in small (~0.5mm) spacings, with a good mixture of support and flexibility. UR5608 delivers a dielectric strength of 18 kV/mm and is UL94 V-0 approved Despite the resin having a lower thermal conductivity of 0.78 W/m.K than the original specification, the low viscosity UR5608 proved to be highly successful at eliminating any air gaps in the system, which dramatically reduced the thermal resistance.

The automotive customer tested UR5608 and Electrolube worked with them to achieve the most efficient production processes by recommending gently heating the material and potting the unit at a slight angle to further improve flow and flush out all air pockets from the unit. When tested, UR5608 flowed well through the customer’s unit, and they achieved the heat dissipation that was required. UR5608 was subsequently approved for the application after demonstrating effective heat transfer between certain hot components, inductors and capacitors, and the liquid cooling channels within their aluminium metal casing.

Bethan Massey, Global Product Manager for Encapsulation Resins at Electrolube, part of MacDermid Alpha Electronics Solutions, comments, "Our automotive customer was very pleased with the solution that we offered them, and we are confident that our problem-solving capabilities and commitment to providing innovative and reliable solutions, will ultimately secure our position as the leading provider of electro-chemical products to the automotive industry.”

MacDermid Alpha Electronics Solutions enables electronics interconnection through the innovative specialty chemicals and materials from our Alpha, Compugraphics, Electrolube, Kester, and MacDermid Enthone brands. We serve all global regions and all steps of device manufacturing within every segment of the electronics supply chain. The experts in our Semiconductor Solutions, Circuitry Solutions, and Assembly Solutions divisions collaborate with OEMs and fabricators in the implementation of new technologies that redefine what is possible in device design. Our world class technical service is constantly at hand to ensure optimized outcomes in yield and productivity. Our solutions can increase throughput, reduce carbon footprints, lower total cost of ownership, and enable electronics innovation.