Low Dielectric Polyimide Aerogels As Substrates for Lightweight Patch Antennas

Abstract

The dielectric properties and loss tangents of low-density polyimide aerogels have been characterized at various frequencies. Relative dielectric constants as low as 1.16 were measured for polyimide aerogels made from 2,2'-dimethylbenzidine (DMBZ) and biphenyl 3,3',4,4'-tetracarbozylic dianhydride (BPDA) cross-linked with 1,3,5-triaminophenoxybenzene (TAB). This formulation was used as the substrate to fabricate and test prototype microstrip patch antennas and benchmark against state of practice commercial antenna substrates. The polyimide aerogel antennas exhibited broader bandwidth, higher gain, and lower mass than the antennas made using commercial substrates. These are very encouraging results, which support the potential advantages of the polyimide aerogel-based antennas for aerospace applications.

Evolution of surface chemistry and morphology of hyperbranched polysiloxane polyimides in simulated atomic oxygen environment

“…Polyimides, in particular aromatic polyimides like Kapton ® H, are extensively used onboard spacecrafts mainly as surface protective materials and lightweight flexible substrates in solar cells, owing to its inherent strong mechanical strength, high-temperature stability and desirable dielectric properties [3][4][5][9][10][11][12][13][14][15]. However, the presence of AO in LEO makes a considerable threat to polyimides, which can cause significant reduction in physical, mechanical and optical properties of polyimides due to its ultra-strong oxidability [3][4][5].…”

Enabling Simultaneous Extreme Ultra Low-k in Stiff, Resilient, and Thermally Stable Nano-Architected Materials

“…27,28 To date, no material with a k below 1.42 (at 1 MHz), whose mechanical properties were also investigated has been reported. 4 Figure 1 shows the fabrication process of capacitors that contain nano-architected dielectrics.…”

Synthesis and characterization of flexible and high-temperature resistant polyimide aerogel with ultra-low dielectric constant

“…The dielectric constants and dissipation factors for PI aerogels have also been investigated in detail. For instance, Meador and coworkers studied the dielectric properties of PI aerogels and investigated their potential applications as substrates for lightweight patch antennas for aerospace applications [23,24]. Relative k values as low as 1.16 at a frequency of X-band (~11-12 GHz) were obtained for PI aerogels made from 3,3′,4,4′-biphenyl tetracarboxylic dianhydride (BPDA), 2,2′-dimethylbenzidine (DMBZ), and 1,3,5-tris(4-aminophenoxy)benzene (TAB) crosslinker.…”