Morphologically correlated surface characteristics of poly (trimethylene terephthalate)/multiwalled carbon nanotube nanocomposites

In the present work the formation of nano-composites by blending an insulator polymer, poly (trimethylene terephthalate), PTT, with a conducting nano-filler (multiwalled carbon nanotubes, MWCNT) is studied and their surface properties, especially wettability and morphology, are investigated. The PTT/MWCNT nanocomposites show significant enhancements in their non-wettability with the highest water contact angle (θ) of 115° for the PTT/0.5%MWCNT composite, compared to 74° for PTT. Since MWCNT is hydrophobic in nature no correlation of MWCNT content with θ value is seen but a direct correlation of θ with surface roughness data obtained from scanning electron microscopy and atomic force microscopy studies could be made. Various wettability parameters including total surface free energy, work of adhesion, interfacial free energy, spreading coefficient and Girifalco-Good's interaction parameter were also evaluated for the nanocomposites.