Microwave non-destructing testing of rubber at X-band

Abstract

In this paper, the measurement of complex dielectric constant of natural rubber at microwave frequencies is reported. A free space, non-destructive technique was used to measure the parameter for several rubber samples at X band. The samples were prepared using different amounts of carbon filler to alter the dielectric properties so that the relation between filler content and ε r can be investigated. Our studies show that ε r and tan δ increase with the filler content. In addition, ε r showed a decreasing trend, while tan δ increased with frequency.

Flexible Antennas Based on Natural Rubber

“…With higher filler contents, the effect becomes more noticeable. The fact that the addition of filler increases tan δ implies that the material becomes more lossy thus leading to an increase in the electrical conductivity, in confirmation with [12]. Furthermore, the addition of carbon up to 20% weight can give a nine-order of magnitude increase in conductivity, ranging from 10 −9 to 10 S/m [9].…”

“…Compared to our previous paper [12], the rubber samples used in this latest work were prepared using a new improved filler formulation (CB N330) and with different filler contents varying from 0% to 60%. The rubber formulation was also new and included Standard Malaysian Rubber L (SMR L), zinc oxide, Antioxidant 2246 (2,2'-Methylenebis (4-methyl-6-tertbutylphenol)), sulphur and zinc diethyldithiocarbamane.…”

“…There are several established techniques available to determine the dielectric properties of polymers, and several reports on the study of the dielectric properties of rubber appeared in the literature, conducted at various frequency ranges. Most involved the use of waveguide or probes [6,7], including our work based on free-space non-destructive testing [12]. These are standard methods based on Von-Hippel.…”

Characterizations of Flexible Wearable Antenna based on Rubber Substrate

“…Its major effect is related with the location of antenna on the body and type of antenna being used. Natural rubber based patch antenna due to full ground plan reduces back radiations while placing near human body [13]. It is exciting that Flexible antennas designed with natural rubber are suitable candidate for wearable antennas in Body Area Networks (BAN's).…”