Effect of Processing Routes on the Performance of Reduced Graphene Oxide‐Enhanced Polyamide 6

Reduced graphene oxide (rGO)‐reinforced polyamide 6 (PA6) nanocomposites were developed using industrially scalable masterbatch dilution strategies to establish a practical route for producing multifunctional materials at very low filler loadings. A concentrated PA6 masterbatch containing 2.0% w/w rGO was diluted to obtain nanocomposites with 0.05% and 0.10% w/w rGO through two processing routes: (i) a conventional two‐step process involving twin‐screw compounding followed by injection molding and (ii) direct dilution during injection molding using different screw configurations. The influence of processing on structure–property relationships was investigated by differential scanning calorimetry, thermogravimetric analysis, X‐ray diffraction, tensile testing, contact‐angle measurements with AdBlue, long‐term ethanol absorption experiments, and accelerated UV‐aging tests. Both the conventional route and the single‐step injection‐molding route employing a long screw achieved homogeneous rGO distribution, whereas the short‐screw configuration resulted in insufficient mixing and inferior mechanical properties. The incorporation of rGO using the two‐step process preserved the thermal transitions and crystalline structure of PA6 while moderately increasing stiffness and influencing crystallinity at higher filler loading. In addition, the nanocomposites exhibited reduced ethanol uptake, increased hydrophobicity toward AdBlue, and improved resistance to UV‐induced yellowing and surface degradation compared with neat PA6. These improvements were achieved without compromising the processability or intrinsic characteristics of the polymer matrix. The results demonstrate that direct masterbatch dilution during injection molding, when combined with an optimized screw configuration, can provide an efficient alternative to conventional multi‐step compounding. This approach offers a scalable and cost‐effective route for manufacturing graphene‐enhanced PA6 components with improved mechanical performance, chemical resistance, and environmental durability for automotive and industrial applications.