EFFECT OF MOISTURE CONTENT AND FREQUENCY VARIATION ON DIELECTRIC PROPERTIES OF BAMBOO (Phyllostachys heterocycla cv. pubescens)

Abstract

Moisture content of bamboo and frequency are the most important factors that affects dielectric properties of bamboo materialDielectric properties of bamboo is one of the most important factors to determine the high-frequency hot pressing process parameters of glued laminated bamboo... Therefore Bamboo was adjusted moisture content under laboratory conditions for 0-18%. Effect of moisture content and frequency variation on dielectric properties of bamboo was determined by using the 4294A Precision Impedance Analyzer with the 16451B. Dielectric properties including dielectric constant (e’) and dielectric loss tangent (tan d) have been done in the moisture content range from 0% to 18% and in the frequency range from 60 Hz to 6 MHz. The results showed that the dielectric constant (e’) and tan d increase with the increasing moisture content and decrease with the increasing frequency. Dielectric constant and tan d increased slowly with the moisture content below fiber saturation point (FSP), increased sharply with the moisture content around the FSP. Dielectric constant and tan d decreased obviously with the frequency below 6 kHz, but changed slowly when it above 6 kHz.