Tailored interphase and thermal interface resistance of self‐assembled thermally reduced graphene oxide–polyamide hybrid/epoxy composites with enhanced thermal conductivity

Abstract

Thermally reduced graphene oxide–polyamide (TrGO‐PA) hybrids were fabricated by self‐assembly between TrGO nanosheets and PA microparticles, and the dispersibility, interphase extension, and thermal conduction mechanism of TrGO‐PA/epoxy (EP) composites were investigated. Most of the oxygen‐containing functional groups of TrGO were removed, and a conjugated structure of graphene was recovered. TrGO was distributed evenly on the PA surface via electrostatic adsorption between TrGO and PA, which resulted in the inhibition of TrGO aggregation in the epoxy matrix. Compared with that of TrGO/EP and PA/EP composites, the thermal interface resistance (RTIM) of TrGO‐PA/EP composites was greatly decreased to 38.3 mm2 kW−1 and the thermal conductivity was improved to 0.268 W/(m K), which was attributed to the enhanced dispersibility of TrGO‐PA and the enlarged interphase in TrGO‐PA/EP composites. A schematic model of thermal conduction mechanisms was proposed based on the formation of contiguous thermal transfer pathways by bridged TrGO adsorbed on well‐dispersed PA microparticles in TrGO‐PA/EP composites. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47826.

Molecular dynamics simulation of the formation mechanism of the thermal conductive filler network of polymer nanocomposites

“…Hence, it can be concluded that smaller NPs contribute to the construction of a filler network, which implies a higher TC. However, this does not seem to be consistent with many experimental results [56][57][58] in which larger fillers more easily form an overlapping network and lead to a higher thermal conductivity of polymer composites. A conductive network formed by larger fillers could result in more heat being transferred by the high thermal conductivity fillers themselves.…”

New triepoxy monomer and composites for thermal and corrosion management

“…The comparison of thermal conductivity of epoxy composites with different fillers for the current study and previous works is shown in Table 4. [31,35,36,[41][42][43][44][45][46][47] The composite with 12 wt % (TC = 0.590 W/mK) is useful for electronic circuit encapsulation as sufficient thermal management is achieved, one such electronic circuit encapsulation is shown in Figure 9.…”

“…[59,60] The corrosion resistance further increased for DHMMPE/GA composite (1%), that is, 1.5165 × 10 −4 mm/year, which is due to hydrophobic nature, good mechanical properties, and large surface area of graphene [61] and good impermeability of graphene. [55] Further increase of GA [36] Exfoliated graphite 8 wt% 0.500 [41] Reduced graphene oxide 0.5 wt% 0.184 [42] CNT 1.5 wt% 0.183 [43] MWCNT 0.5 wt% 0.247 [44] Silicon carbide nanowires 3 wt% 0.449 [35] Al 2 O 3 67 wt% 0.57 [45] BN 35.5 wt % 0.59 [45] AlN 57 vol% 1.5 [46] SiO 2 5 wt% 0.177 [47] T-ZnO 50 wt% 4.38 [31] Abbreviations: AlN, aluminum nitride; BN, boron nitride; T-ZnO, tetrapodshaped ZnO. concentration (3-5%) in the composite did not increase the corrosion resistance but decreased.…”

High‐thermal‐conduction and low‐cost composite originated from the tight packing structure of boron nitride sheets and binary alumina balls

“…However, due to the small size effect, the fillers tend to agglomerate in the polymer, which is not conducive to the formation of the ordered heat conductive framework. [ 11–13 ] Therefore, current research on thermally conductive composites has mainly focused on uniformly dispersing small‐sized fillers and regulating the arrangement of fillers. [ 6,14–17 ] By constructing heat conduction paths through three‐dimensional (3D) network, the high thermal conductivity of the material can be obtained.…”