Poly(ε-caprolactone) filled with polydopamine-coated high aspect ratio layered double hydroxide: Simultaneous enhancement of mechanical and barrier properties

Inspired by the versatile adhesion capability of marine adhesive proteins, core-shell structured polydopamine-coated layered double hydroxide (LDH@PDA) were prepared successfully by in-situ growing PDA on the surface of MgAl-LDH with a high aspect ratio. LDH@PDA/poly(epsilon-caprolactone) (PCL) nanocomposites were prepared by blending LDH@PDA and pure PCL via solution casting method to obtain homogeneous films. The results of thermal analysis confirmed that LDH@PDA can act as a nucleating agent. And thermal stability of nano composites was improved due to core-shell structured LDH@PDA. With incorporation of as low as 1 wt% of LDH@PDA, a 20% increase in tensile strength (41.1 MPa), 26% increase in elongation at break (772%) and 26% reduction in the oxygen relative permeability were achieved. The improvement in the mechanical and gas barrier properties of nanocomposites at low filler loading was attributed to the strong interfacial interaction of LDH@PDA wtih the PCL matrix.