Enhancement of thermal and mechanical properties of silicone rubber with γ-ray irradiation-induced polysilane-modified graphene oxide/carbon nanotube hybrid fillers

In this study, a polysilane-modified graphene oxide (GO) and carbon nanotube (CNT) nanocomposite (GO/CNTs-Si) was prepared as a thermal conductive nanofiller to enhance the thermal and mechanical properties of silicone rubber composites. By γ-ray-radiation 3-methacryloxypropyltrimethoxy silane (MPTMS) was polymerized on the surface of GO and CNTs to improve the interfacial interaction between the GO/CNTs-Si and SR matrix. FTIR characterization results demonstrated that polysilane modified the GO/CNTs successfully. The pristine GO/CNTs and resultant GO/CNTs-Si were individually incorporated into α,ω-dihydroxypolydimethylsiloxane to vulcanize SR composites. Compared with SR-GO/CNTs, SR-GO/CNT-Si exhibited better mechanical and thermal performance. Moreover, the time-dependent complex modulus of SR-GO/CNTs-Si was much higher than that of SR-GO/CNTs, which indicates longer service time and more stable performance. In terms of electronic packaging, SR-GO/CNTs exhibited better performance than the 1180B counterpart. The low value of warpage of chip packaged by SR-GO/CNTs implied that SR-GO/CNTs-Si could have potential application as the thermal interface electronic packaging material. In this work, functionalized silicon rubber with hybrid nanocarbon filler was prepared. The composites with good resistance ability to stress relaxation can be used as underfill to improve the thermo-mechanical reliability of flip-chips.