(611c) Influence of the Functional Group, Type of Filler and Processing on the Mechanical Properties of Swcnt/nylon and Graphene Sheet/nylon Composites

We have recently prepared nylon 6,10 nanocomposites using functionalized single wall carbon nanotubes (SWCNTs) and our interfacial in situ polycondensation method. The specific functional groups ?(CH2)₄COCl and ?(CH2)₉COCl on the sidewalls of SWCNT were designed to covalently link nanotubes to the nylon matrix via alkyl segments. The composites with functionalized SWCNT show significant improvements in tensile modulus, strength and toughness relative to nylon and nylon modified with non-functionalized SWCNT. The alkyl linkages at the SWCNT/nylon 6,10 interface contribute significantly to improving the toughness of the composites.

We have now extended this effort to nylon 6,10 nanocomposites with functionalized graphene sheets. The graphene sheets were functionalized with ?COCl, ?(CH2)₄COCl, and ?(CH2)₉COCl using the Birch type reaction protocol and incorporated into nylon 6,10 using our in situ polycondensation method. The composites were melt spun into fibers or hot pressed into films for further characterization. The influence of the functional groups on the polymer-particle interface is being examined by characterizing the morphology and the tensile properties. Subsequently, influence of the type of filler on the mechanical properties will be studied by comparing the tensile properties of the graphene composites with those of the SWCNT composites. Finally, the processing effects on the tensile properties are investigated by comparing the tensile properties of the films with those of the fibers. The broad implications of this work include making an informed decision in the selection of the functional group, type of filler and the type of processing to tune the mechanical properties of polymer nanocomposites.