A comparative study on the influences of whisker and conventional carbon nanotubes on the electrical and thermal conductivity of polyether ether ketone composites

Abstract

In this study, the electrical and thermal conductivity of polyether ether ketone (PEEK)/carbon nanotubes (CNTs) with different types, namely whisker CNTs (Wh‐CNTs) and conventional CNTs were compared. PEEK/CNTs composites were melt mixed in PEEK via two screw extrusion technology. Moreover, the effects of different methods for mixing of PEEK/Wh‐CNTs, namely, dry mixing, wet mixing and melt mixing, were compared. The electrical and thermal properties were analyzed. A high thermal conductivity value of about 0.741 W/(m K) could be obtained upon loading with 10 wt% Wh‐CNTs and the PEEK/Wh‐CNTs composites had low volume resistivity value of 10.96 Ω cm at 10 wt% loading via melt mixing. Thermal conductivity values of 1.066 W/(m K) (out‐of‐plane) and 1.50 W/(m K) (in‐plane) were achieved with 10 wt% loading by wet mixing. Experimental results of out‐of‐plane thermal conductivity were more consistent with the Nan model. PEEK/Wh‐CNTs composites prepared by wet mixing exhibited higher thermal conductivity than the composites mixed using the two other methods. As the content of Wh‐CNTs in wet mixed PEEK/Wh‐CNTs nanocomposites increased, electromagnetic interference (EMI) shielding effectiveness (SE) was improved. The PEEK/Wh‐CNTs composites were 0.6 mm thick and showed an EMI SE of 21.5 dB.

Evaluation thermal degradation kinetics of ionic liquid assisted polyetheretherketone‐multiwalled carbon nanotubes composites

“…Conversely, non‐covalent functionalization strategies are environmentally benign, do not alter the properties of carbon nanotubes, and integrate polymers through π‐π interactions and van der Waals forces 4 . The non‐covalent functionalization is accomplished by solution mixing 5 and melt blending 6 . Several investigations have been conducted in which PEEK/MWCNT nanocomposites were synthesized using melt blending and solution mixing, and it was discovered that attaining uniform dispersion of MWCNT in PEEK was challenging owing to their poor dispersibility and large aspect ratio (approx.…”

“…4 The non-covalent functionalization is accomplished by solution mixing 5 and melt blending. 6 Several investigations have been conducted in which PEEK/MWCNT nanocomposites were synthesized using melt blending and solution mixing, and it was discovered that attaining uniform dispersion of MWCNT in PEEK was challenging owing to their poor dispersibility and large aspect ratio (approx. 300-1000).…”

Graphene Oxide/Carbon Tube Composite Films with Tunable Porous Structures for Electromagnetic Interference Shielding

“…Whisker carbon tubes (wCTs), a new type of CNT with straight and whisker-like structures, have high purity, crystallinity, strength, and dispersibility. wCTs possess a light weight and excellent electrical conductivity of 8156 S/m, which are widely used in pressure sensors, MA, thermal conductivity, and EMI shielding . The multiple straight “branches” structure of wCTs may provide more touchpoints between tubes and increase the path of electron transmission after assembly.…”

“…However, single components of wCT material cannot assemble into a bulk material for application of EM wave attenuation due to the weak interaction between tubes. Meanwhile, the introduction of an insulating polymer into wCTs severely deteriorates electrical conductivity and it is difficult to achieve satisfactory EMI shielding performance …”

Effect of ionic liquids on thermomechanical properties of polyetheretherketone‐multiwalled carbon nanotubes nanocomposites

“…3,4 The PEEK/MWCNT composites have been manufactured by several methods to address the role of MWCNTs in PEEK, including solution mixing, 5 compounding and injection molding, 6 chemical modification of CNTs 7 and melt blending of PEEK with MWCNTs. 8 However, the homogeneous and good dispersion of MWCNTs within PEEK remains challenging due to their inherently inert nature, large aspect ratio, and low dispersibility. 9,10 Ionic liquids (ILs) are low vapor pressure tunable solvents with strong solvation interactions and good thermal stability, rendering appropriate alternatives for homogenous MWCNTs distribution in the polymer matrices.…”