Premium
Design of electrical conductive poly(lactic acid)/carbon black composites by induced particle aggregation
Author(s) -
Kim Ji Hwan,
Hong Joung Sook,
Ahn Kyung Hyun
Publication year - 2020
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.49295
Subject(s) - carbon black , materials science , particle (ecology) , percolation threshold , composite number , composite material , phase (matter) , ternary operation , particle size , conductivity , chemical engineering , electrical resistivity and conductivity , chemistry , organic chemistry , natural rubber , oceanography , engineering , computer science , electrical engineering , programming language , geology
The electrical conductivity of ternary composites composed of a biopolymer blend with conductive particles (carbon black [CB]) is induced by the control of particle dispersion in the dispersed phase. If the CB particles have higher chemical affinity for the secondary phase (poly(caprolactone) [PCL]]) than the matrix (poly(lactic acid) [PLA]), especially as the concentration of the PCL phase decreases significantly to 4 wt%, the PCL phase induces the aggregation of CB particles beyond the selective localization, resulting in a shift of the particle percolation threshold to a lower concentration of particles (2.44 wt% CB). Moreover, the mixing ratio between the CB and the PCL phase significantly affects the formation of percolation of particles. When the mixing ratio of CB to PCL is equivalent (1:1), the ternary composite shows high electrical DC conductivity above 1 S/m with 10 wt% CB. The addition of a small amount of PCL induces the formation of particle aggregates with a high aspect ratio, providing more electron transfer pathways due to the multiple points of contact between the particle aggregates (power law scaling exponent of the composites ~2.14). Meanwhile, a binary composite (PLA/CB) never reaches high electrical conductivity of 1 S/m and even requires a greater concentration of CB (13 wt% CB for 10 −3 S/m) to accomplish electron transfer because of the small aspect ratio of randomly dispersed particle aggregates (power law scaling exponent ~3.20).