Filler conducting

Fillers may decrease thermal conductivity. The best insulation properties of composites are obtained with hollow spherical particles as a filler. Conversely, metal powders and other thermally conductive materials substantially increase the dissipation of thermal energy. Volume resistivity, static dissipation and other electrical properties can be influenced by the choice of filler. Conductive fillers in powder or fiber form, metal coated plastics and metal coated ceramics will increase the conductivity. Many fillers increase the electric resistivity. These are used in electric cable insulations. Ionic conductivity can be modified by silica fillers. 

The effects of nano-structured carbon fillers [fuUerene C60, single wall carbon nanotube (SWCNT), carbon nanohom (CNH), carbon nanoballoon (CNB), and ketjenblack (KB) and conventional carbon fillers [conductive grade and graphi-tized carbon black (CB)]] on conductivity (resistance), thermal properties, crystallization, and proteinase K-catalyzed enzymatic degradation of PLA films were investigated by Tsuji et al. [70]. The researchers found that the addition of 1 wt% SWCNT effectively decreased the resistivity of PLA film compared with that of conventional CB. The crystallization of PLA further decreased the resistivity of films. The addition of carbon fillers, except for C60 and CNB at 5 wt%, lowered the glass transition temperature, whereas the addition of carbon fillers, excluding... 

SBR matrix and PANI filler Conductivity, swelling, thermal and mechanical properties found to depend on PANI concentration and ratio between PANI-DBSA and PSS Martins et al. 2006... 

Supplier Designation Resin Filler Conductive Tg, °C Thermal conductivity, Thixotropic Modulus, W/mK index GPa Viscosity, m Pa-s (= cP) Cure... 

Suitable electrically conductive fillers include carbon black, carbon fibers, vapor grown carbon fibers, carbon nanotubes, metal fillers, conductive non-metal fillers, metal coated fillers, etc (7). 

Several research groups [90, 91] have shown that the choice of the polymer matrix can significantly influence the location of the conductive filler in polymer blends due to the different interactions between these polymers and the filler. Conductive nanofiUers are often located in the polymer phase that has good affinity with them. Fu et al. [92] showed that the functionalization of filler can also change the distribution of the filler in polymer blends. Moreover, Potschke et al. [89] used a reactive component to tune the interaction between SAN and CNTs in a polymer blend based on PC and SAN. It is observed that CNTs transferred from the PC phase to the SAN phase after the addition of the reactive component due to an enhanced interaction. 

At room temperature, conductivity was found to increase with the addition of fillers, generally reaching a maximum between 5 and 15 wt% of filler. ° For large amounts of filler, conductivity decreased, which was associated with the blocking of conduction pathways by the electrically insulating nanoparticles. 

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