Carbon Nanotube–filled Auto Compound Is Powder Coatable

Korea’s LG Chem has started supplying carbon nanotube (CNT)–filled engineering plastic compounds to Japan’s Mitsubishi Motors for the front fenders of its RVR, Delica D:5, and Outlander models. The injection-molded fenders can be powder-coated thanks to the electrical conductivity of the CNT-filled polyphenylene ether (mPPE) and polyamide (PA66) alloy, dubbed Lucon TX5007.

The front fender is located on the side of the vehicle and not only acts as a key factor in the exterior design but also protects wheels from road debris. Consequently, it must be mechanically robust while having an exterior quality that maintains design integrity with the rest of the car body.

Lucon TX5007 reportedly has excellent electrical conductivity and mechanical properties. In addition, its outstanding heat resistance makes it suitable for the electrostatic in-line painting process used by automakers that operates at temperatures of 200°C and higher. At the same time, the alloy delivers dimensional stability thanks to its low coefficient of linear thermal expansion (CLTE).

In general, using plastics in place of steel/aluminum contributes to automotive lightweighting. When a plastic fender is used, the weight of the vehicle is reduced by about 4 kg, which also improves fuel efficiency.

In addition to Lucon TX5007, LG Chem offers a broad portfolio of compounds that can be used for large automotive exterior parts that undergo the powder coating process. These grades can be customized to meet automotive suppliers’ diverse parts requirements for fenders, bumper panels, hoods, tailgates, fuel doors, and side mirrors.

LG Chem is using CNT, a filler that delivers excellent conductivity even at low loadings, in its engineering plastics to support the diverse requirements of customers. Since this material can cover a wider range of electrical conductivity compared with other carbon fillers such as carbon black and carbon fiber, it is considered an optimal solution for powder coating. LG Chem is currently expanding its capacity for CNT, with a fourth plant expected to come on stream in 2024, which will ensure reliable supply of high-quality products for powder coating, according to the company.