Poly(1,3‐butylene adipate) plasticized poly(lactic acid)/carbon black as electrical conductive polymer composites

Poly(1,3-butylene adipate) (PBA) as the plasticizer for poly(lactic acid) (PLA) and carbon black (CB) as conductive filler, electrically conductive polymer composites (CPC) with different CB and PBA contents were prepared. Fourier transform infrared revealed that the interaction existed between PLA/PBA matrix and CB filler, and PBA could improve this interaction. The rheology showed that CB could obviously improve the apparent viscosity and decrease the fluidity of the composites, but just the reverse for PBA. PLA/PBA/CB composites exhibited the low electrical percolation thresholds of 0.516, 1.20, 2.46, and 2.74 vol% CB at 30, 20, 10, and 0 wt% PBA. The conductivity of the composite containing 3.98 vol% CB and 30 wt% PBA reached 1.67 S/cm. Scanning electron microscopy revealed that the addition of PBA facilitated the dispersion of PLA/CB composites. PBA could dramatically increase the elongation at break of plasticized PLA. But high-PBA content caused the lowering of tensile strength. With the increasing of CB contents, the enforcement effect on the plasticized PLA became more obvious. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers