Influence of carbon black on the properties of plasticized poly(lactic acid) composites

Using acetyl tributyl citrate (ATBC) and poly(1,3-butylene adipate) (PBA) as the plasticizer of poly(lactic acid) (PLA) and carbon black (CB) as reinforced filler, high performance composites were prepared in melting blend. Fourier transform infrared spectroscopy revealed that the interaction existed between PLA and CB, and plasticizer could improve this interaction. The rheology showed that plasticizer could obviously improve the fluidity of the composites, but just the reverse for CB. Scanning electron microscopy revealed that the addition of plasticizer facilitated the dispersion of the CB in PLA. With the increasing of CB content, the enforcement effect, storage modulus and glass transition temperature increased. The elongation at break of PLA/PBA (30 wt%) could be above 600%, which was higher than the same weight ATBC plasticized PLA. Moreover, CB could restrain the thermally induced migration of plasticizer in plasticized PLA. Compared with ATBC, PBA was a thermal stable plasticizer for PLA.