Magnetic-Oriented Nickel Particles and Nickel-Coated Carbon Nanotubes: An Efficient Tool for Enhancing Thermal Conductivity of PDMS Composites

In this study, PDMS composites are thermally cured with nickel particles and nickel-coated carbon nanotubes as fillers. Both fillers are oriented with the aim to increase the thermal conductivity of the silicone polymer network, due to the formation of a continuous thermal path. Scanning electron microscopy (SEM) gives a picture of the polymer network's morphology, proving the effective alignment of the nickel particles. Rheology and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) studies confirm the full curing of the silicon network and no influence in the curing kinetics of the type and content of fillers and their orientation. Dynamic mechanical thermal analysis (DMTA) and tensile analysis show instead different thermo-mechanical behavior of the polymer network due to the presence of different fillers, different fillers percentage, and orientation. Finally, the thermal transmittance coefficient (k) is studied by means of hot disk analysis, revealing the increment of almost 200% due to magnetic filler orientation.

Automated summary

In this study, PDMS composites were prepared by thermally curing nickel particles and nickel-coated carbon nanotubes as fillers. The fillers were oriented to enhance the thermal conductivity of the silicone polymer network. SEM results confirmed the effective alignment of nickel particles. Rheology and ATR-FTIR studies showed that the fillers and their orientation did not affect the curing kinetics of the silicone network. DMTA and tensile analysis revealed different thermo-mechanical behaviors due to the presence of different fillers and their orientation. Hot disk analysis demonstrated that magnetic filler orientation led to a nearly 200% increase in the thermal transmittance coefficient.