Premixed cellulose nanocrystal reinforcement of polyamide 6 for melt processing

Abstract This work presents a method of industrially viable processing of nanocellulose‐reinforced polyamide 6 (PA 6). Cellulose nanocrystal (CNC)‐reinforced PA 6 is gaining attention as a promising material for use in the automotive industry due to its highly crystalline, low density, and environmentally friendly nature. However, the low‐thermal degradation temperature of CNCs presents problems when melt processing at high temperatures, making it difficult to produce the nanocomposite on a large scale. This article presents a methodology of master batching (MB) using planetary ball milling to embed the CNCs in PA 6. The process of MB CNCs with PA 6 to thermally buffer them was compared to direct milling and hand mixing, prior to melt processing with compression molding. The milled composites had final CNC compositions of either 5 or 10 wt%. Through thermal analysis, it was seen that although both milling methods thermally buffered the CNCs, the presence of the low‐molecular weight PA 6 in the MB samples resulted in higher thermal stability. In addition to this, the mechanical analysis showed that the MB samples with 5 wt% CNCs had optimum Young's moduli, ultimate tensile strength, and elongation % at break. Overall, the use of milling for MB to coat the CNCs in polymer is a promising alternative to traditional processes and has potential as a method of industrially manufacturing cellulose reinforced polymer composites.