Polyurethane / Carbonaceous Nanofillers based Nanocomposite Films through Thermo-Chemical route for Gas Barrier Property

Abstract

The carbonaceous nanofillers like acid functionalized multiwall carbon nanotube (f-MWCNT as 1D), edge functionalized hydroxylated few layers graphene (f-FLG as 2D) and f-MWCNT embedded into the graphene flakes as 3D were incorporated into thermoplastic polyurethane by thermo-responsive gelation method for the preparation of cellular structures. The concentration of nanofillers was varied as 0.1, 1 and 5 wt%. The prepared cellular structures were characterized using SEM, XRD and FTIR. The cellular structured polyurethane was then compounded by twin-screw extrusion.  The compounded material was used to prepare the films by compression moulding technique. The functionalized carbonaceous nanofillers were also incorporated into the polyurethane by compounding   directly in a twin-screw extruder. The dispersion of the nanofillers was studied by scanning electron microscopy (SEM). SEM studies showed very good dispersion of nanofillers in the compounded materials made through cellular structure route. The developed films were studied for the gas barrier properties by measuring the helium gas permeability. The addition of 1 weight percentage of tailor made hierarchical carbonaceous nanomaterials in TPU by thermo-responsive gelation route followed by melt mixing resulted reduced helium gas permeability from 1287 to 548 cm³/m²/day.