Effects of Orientation and Dispersion on Electrical Conductivity and Mechanical Properties of Carbon Nanotube/Polypropylene Composite

Abstract

The orientation and dispersion of nanoparticles can greatly influence the conductivity and mechanical properties of nanocomposites. In this study, the Polypropylene/ Carbon Nanotubes (PP/CNTs) nanocomposites were produced using three different molding methods, i.e., compression molding (CM), conventional injection molding (IM), and interval injection molding (IntM). Various CNTs content and shear conditions give CNTs different dispersion and orientation states. Then, three electrical percolation thresholds (4 wt.% CM, 6 wt.% IM, and 9 wt.% IntM) were obtained by various CNTs dispersion and orientations. Agglomerate dispersion (Adis), agglomerate orientation (Aori), and molecular orientation (Mori) are used to quantify the CNTs dispersion and orientation degree. IntM uses high shear to break the agglomerates and promote the Aori, Mori, and Adis. Large Aori and Mori can create a path along the flow direction, which lead to an electrical anisotropy of nearly six orders of magnitude in the flow and transverse direction. On the other hand, when CM and IM samples already build the conductive network, IntM can triple the Adis and destroy the network. Moreover, mechanical properties are also been discussed, such as the increase in tensile strength with Aori and Mori but showing independence with Adis. This paper proves that the high dispersion of CNTs agglomerate goes against forming a conductivity network. At the same time, the increased orientation of CNTs causes the electric current to flow only in the orientation direction. It helps to prepare PP/CNTs nanocomposites on demand by understanding the influence of CNTs dispersion and orientation on mechanical and electrical properties.

Mechanical, Thermal, and Electrical Properties on 3D Printed Short Carbon Fiber Reinforced Polypropylene Composites

“…Carbon materials commonly used as reinforcing components, such as graphene, carbon fibers, and carbon nanotubes, have more functionality, taking into account mechanics, thermodynamics, and electricity. − For example, carbon nanofiber (CNF)/polycaprolactone (PCL) composites were 3D printed into electromagnetic interference (EMI) shielding parts . The morphology characteristics of the reinforcing components, such as orientation and length, have a strong impact on the performance of composite products. , Almeshari et al prepared short carbon fiber-reinforced PP composites using FDM-3D printing technology and studied the relationship between the morphology characteristics of carbon fibers and the mechanical properties of the composites. Yi et al compared the effects of different carbon fiber lengths on the thermal conductivity and mechanical properties of PVDF-based composites.…”

“…23 The morphology characteristics of the reinforcing components, such as orientation and length, have a strong impact on the performance of composite products. 14,20 Almeshari et al 24 prepared short carbon fiber-reinforced PP composites using FDM-3D printing technology and studied the relationship between the morphology characteristics of carbon fibers and the mechanical properties of the composites. Yi et al 25 compared the effects of different carbon fiber lengths on the thermal conductivity and mechanical properties of PVDF-based composites.…”

“…To enrich the functionality of 3D printed polymers, granular or fibrous reinforcing materials are added to the polymer matrix. ,− For example, Peng et al combined the ball-milling strategy with FDM-3D printing technology to design and implement a linear low-density polyethylene (LLDPE)/boron nitride (BN)@graphene nanosheet (GNP) composite parts with dual network structures for high-efficiency thermal conductivity and electrical interference shielding . Li et al innovatively designed the thermoplastic polyurethane (TPU)/Ti 3 C 2 Tx (MXene)/MnFe 2 O 4 /multiwalled carbon nanotube (MWCNT) composite materials using parametric Voronoi structures with different pore sizes and porosity upon FDM-3D printing for sensor and electromagnetic shielding applications .…”

Concurrent effect of shear flow and CNT presence on crystallization behavior and electrical properties of polypropylene based nanocomposites: A comprehensive structure-property investigation

“…Recently, Mi et al 37 evaluated the effect of CNT contents and shearing conditions on the electrical properties of PP/CNT nanocomposites. In this work, different amounts of CNT in the range of 0-9 wt% were loaded into the PP matrix.…”

The Contribution of the Pore Size of Titanium DC (Direct Current) Sputtered Condensation Polymer Materials to Electromagnetic Interruption and Thermal Properties

“…In addition, various studies on the electrical, magnetic, chemical, physical, and sensing characteristics of composite materials related to electrical conductivity are being conducted [22][23][24][25][26][27][28].…”