Acharya, Ashwin Rajendra (2023-04). Synthesis and Characterization of Graphite Filler-Amine Functional Silicone Rubber Nanocomposite for Use as Thermal Interface Material for Better Heat Dissipation in Electronic Devices. Master's Thesis.
Thesis
Electronic appliances have grown compact and exhibit high power density with each passing day, which has resulted in a surge of heat emanating from these equipment. Superior thermal management solutions have thus become critical for the operation of such devices. Metals have high thermal conductivity (Ks) but when seen at microscopic scale, fail to occupy most crevices between heat conducting surfaces at the interface, thus lowering the actual area of contact resulting in less heat dissipation. Therefore, an elastomer with high thermal conductivity can be used as a thermal interface material (TIM). In this study, we report the synthesis of poly[(aminopropyl) methylsiloxane-co-dimethylsiloxane] - silicone rubber (SR) by base equilibration of 3-aminopropyl-heptamethlcyclotetrasiloxane with octamethylcyclotetrasiloxane and added the graphite via in-situ method, to achieve better dispersion and increase linkage between the matrix and the filler, to form the nanocomposite. We used Nuclear Magnetic Resonance analysis and Fourier Transform Infrared Spectroscopy to confirm the reaction. Furthermore, we investigated the heat vs temperature behavior of the nanocomposite with different graphite loadings to identify crystallization exotherms and melting endotherms on Differential Scanning Calorimetry (DSC). In addition to this, we conducted tests to find out Heat Capacity (as a function of temperature) and Ks at 30oC for varying graphite loading using modulation steps on DSC. Elevated heat capacity and thermal conductivity was observed for graphite with SR as compared to neat SR for given temperature. Therefore, we were successful in synthesizing and consequently improving thermal properties of graphite-SR nanocomposite.
