Finishing, in most cases, is the most expensive step for manufacturing plastic parts in automotive and truck industry; being electrostatic painting is the desired approach for improved quality. For plastic parts to be painted electrostatically, a conductive primer needs to be applied first. In the case of SMC compression molded parts, in‐mold coating (IMC) is the primer material of choice, as it also serves to fill the surface porosity typical in SMC parts. To make the IMC conductive, the current approach is to add carbon black (CB), which results in a black colored primer. In this research, single wall carbon nanotube (SWCNT) was evaluated, as an alternative to CB, to develop a clearer version of conductive IMC. The effect of SWCNTs on both degree of lightness and electrical conductivity was experimentally evaluated. The results indicate that a clearer and slightly more conductive coating than standard IMC can be obtained by adding 0.15 wt% SWCNTs into the base IMC resin, which results in approximately 12.5% paint saving compared to standard IMC. The processability of the modified coating was shown to be only slightly less favorable than standard coating.

中文翻译：

---

降低片状模塑料（SMC）压模的油漆成本

在大多数情况下，精加工是制造汽车和卡车行业塑料零件最昂贵的步骤。进行静电喷涂是提高质量的理想方法。对于要静电喷涂的塑料部件，首先需要使用导电底漆。对于SMC压缩成型零件，模内涂层（IMC）是首选的底漆材料，因为它也可以填充SMC零件中典型的表面孔隙率。为了使IMC导电，当前的方法是添加炭黑（CB），这会导致黑色底漆。在这项研究中，对单壁碳纳米管（SWCNT）进行了评估，以替代CB，以开发出更清晰的导电IMC版本。实验评估了SWCNT对亮度和电导率的影响。结果表明，通过将0.15 wt％的SWCNT添加到基础IMC树脂中，可以获得比标准IMC更透明，导电性更高的涂层，与标准IMC相比，可节省约12.5％的涂料。结果表明，改性涂层的加工性能仅略低于标准涂层。