Abstract
The introduction of the pores into polymers is an efficient method to prepare the materials with low dielectric constant (ε) and low dielectric loss tangent (tan δ). Herein, low-weight polyarylene ether nitrile (PEN)/SiO2 foams with bi-modal pore structure were prepared via supercritical carbon dioxide batch foaming. The effects of SiO2 as heterogeneous nucleation on the dielectric properties, wave-transparent properties, thermal conductivity properties and mechanical properties of PEN/SiO2 foams have been investigated. Compared with PEN/SiO2 films, PEN/SiO2 foams showed excellent properties, which was most probably due to their uniform bi-modal pore morphology. As cell density and the SiO2 weight content was increased, ε and tan δ of the PEN/SiO2 foams decreased to 1.71 and 0.0047, respectively. The PEN/SiO2 foams exhibited ultra-low dielectric constant, showing low temperature and stabilization dielectric properties from −100 °C to 120 °C. Furthermore, the wave-transparent properties of PEN/SiO2 films and foams, which are required for wave-transparent application, were also investigated. The thermal insulating properties of PEN/SiO2 foams were remarkably improved after the pores and SiO2 fillers were introduced into the PEN polymer, with thermal conductivity reaching as low as 0.073 W/m K. PEN/SiO2 foams showed markedly increased elongation at the break, compared with PEN/SiO2 films, whereas tensile strength >50 MPa. The excellent properties of PEN/SiO2 foams indicated their potential as dielectric materials for microelectronics and wave-transparent materials for aerospace technology.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have