Study on lowering the percolation threshold of carbon nanotube-filled conductive polypropylene composites

서지정보

ㆍ발행기관 : 한국탄소학회 ㆍ수록지정보 : Carbon Letters / 15권 / 2호
ㆍ저자명 : Seung Bin Park, Moo Sung Lee, Min Park

목차

1. Introduction
2. Experimental Procedures
3. Results and Discussion
4. Conclusions
Acknowledgements
References

한국어 초록

Conductive polymer composites (CPCs) consist of a polymeric matrix and a conductive filler,for example, carbon black, carbon fibers, graphite or carbon nanotubes (CNTs). The criticalamount of the electrically conductive filler necessary to build up a continuous conductivenetwork, and accordingly, to make the material conductive; is referred to as the percolationthreshold. From technical and economical viewpoints, it is desirable to decrease the conductive-filler percolation-threshold as much as possible. In this study, we investigated the effectof polymer/conductive-filler interactions, as well as the processing and morphological developmentof low-percolation-threshold (Φc) conductive-polymer composites. The aim of thestudy was to produce conductive composites containing less multi-walled CNTs (MWCNTs)than required for pure polypropylene (PP) through two approaches: one using various mixingmethods and the other using immiscible polymer blends. Variants of the conductive PPcomposite filled with MWCNT was prepared by dry mixing, melt mixing, mechanofusion,and compression molding. The percolation threshold (Φc) of the MWCNT-PP compositeswas most successfully lowered using the mechanofusion process than with any other mixingmethod (2-5 wt%). The mechanofusion process was found to enhance formation of a percolationnetwork structure, and to ensure a more uniform state of dispersion in the CPCs. Theimmiscible-polymer blends were prepared by melt mixing (internal mixer) poly(vinylidenefluoride) (PVDF, PP/PVDF, volume ratio 1:1) filled with MWCNT.

영어 초록

Conductive polymer composites (CPCs) consist of a polymeric matrix and a conductive filler,
for example, carbon black, carbon fibers, graphite or carbon nanotubes (CNTs). The critical
amount of the electrically conductive filler necessary to build up a continuous conductive
network, and accordingly, to make the material conductive; is referred to as the percolation
threshold. From technical and economical viewpoints, it is desirable to decrease the conductive-
filler percolation-threshold as much as possible. In this study, we investigated the effect
of polymer/conductive-filler interactions, as well as the processing and morphological development
of low-percolation-threshold (Φc) conductive-polymer composites. The aim of the
study was to produce conductive composites containing less multi-walled CNTs (MWCNTs)
than required for pure polypropylene (PP) through two approaches: one using various mixing
methods and the other using immiscible polymer blends. Variants of the conductive PP
composite filled with MWCNT was prepared by dry mixing, melt mixing, mechanofusion,
and compression molding. The percolation threshold (Φc) of the MWCNT-PP composites
was most successfully lowered using the mechanofusion process than with any other mixing
method (2-5 wt%). The mechanofusion process was found to enhance formation of a percolation
network structure, and to ensure a more uniform state of dispersion in the CPCs. The
immiscible-polymer blends were prepared by melt mixing (internal mixer) poly(vinylidene
fluoride) (PVDF, PP/PVDF, volume ratio 1:1) filled with MWCNT.

참고 자료

없음