Effect of Na+‐MMT Platelets on Monomer Casting Polyamide 6/Polyphenylene Oxide Blends

Summary: Blend composites (95:5) of monomer casting polyamide 6 and polyphenylene oxide (MCPA6/PPO) with and without 0.5 wt.‐% Na+‐montmorillonite (Na+‐MMT) platelets were prepared by in situ AROP of CL using water as a pre‐dispersant of Na+‐MMT. The effect of Na+‐MMT on morphologies of MCPA6/PPO has been studied by scanning and transmission electron micrographs and rotational rheometer, respectively. The domain size of PPO dispersed phase in the MCPA6 matrix decreased significantly from some dozens of micrometers to about 1 µm and all Na+‐MMT was dispersed only in the MCPA6 phase. It is considered that the high aspect ratio of the Na+‐MMT prevented the coalescence of PPO domains during in situ polymerization. The results of DSC indicated that the size of PPO dispersed phase affected the crystalline behavior. Synergistic action of PPO and Na+‐MMT improved the strength and the toughness of nanocomposites compared with that of the pure MCPA6. SEM micrographs of the cryo‐fractured surfaces of (A) MCPA6/PPO (95:5) and (B) MCPA6/PPO/Na+‐MMT (95:5:0.5). magnified image SEM micrographs of the cryo‐fractured surfaces of (A) MCPA6/PPO (95:5) and (B) MCPA6/PPO/Na+‐MMT (95:5:0.5).