Changes in the Interfacial Properties between Poly(butylene terephthalate) and Multi-walled Carbon Nanotubes Bonded with Various Functional Groups

Abstract

The composites of poly(butylene terephthalate) (PBT) and multi-walled carbon nanotubes (MWCNTs) functionalized with carboxylic acid, acyl chloride and ethyl amine were prepared and their properties were characterized. The interfacial adhesion energies between PBT and functionalized MWCNTs were estimated with a drop-on-fiber method combined with a generalized droplet shape analysis method. The interfacial adhesion energies between PBT and functionalized MWCNTs were higher than that between PBT and pristine MWCNT. Among the functionalized MWCNTs, MWCNT containing ethyl amine exhibited the highest interfacial adhesion energy with PBT. When dispersion of MWCNTs in the PBT matrix was examined, composites having high interfacial adhesion energy exhibited better dispersion. PBT composite containing MWCNT functionalized with ethyl amine also exhibited greater adhesion at the interface and reinforcement than that containing pristine MWCNT.