Nanoscale Morphology, Interfacial Hydrogen Bonding, Confined Crystallization and Greatly Improved Toughness of Polyamide 12/Polyketone Blends

Nanostructured polyamide 12(PA12)/polyketone (PK) blends were fabricated by melt compounding. The nanoscale droplet and domain-in-domain morphologies depending on PK content were observed. When the content of PK was 10 vol %, the impact strength of the blend jumped from 6.8 to 111.9 kJ/m(2) and further improved with an increasing content of PK. The toughening mechanism was found to be closely related with the morphology change from nanoscale droplet morphology to domain-in-domain morphology owing to the strong interfacial hydrogen bonding. The nanoscale morphology confinement and interfacial hydrogen bonding enhances the crystallization kinetics, while it lowers down the thermodynamic stability of the crystals. The toughening mechanisms were discussed based on these factors.