Ceramics-Silikáty 53, (1) 48 - 51 (2009)

The article describes the acoustic absorption coefficient of material formed by geopolymer joining agent filled by sand. The geopolymer defined as a clay based inorganic poly-condensed 3D net was used as a substitute of epoxide resin, currently industrially used cementing material of granular media (generally quartz sand). The absorption coefficient α of conventionally used epoxide/sand sample was compared with studied geopolymer/sand mixtures. The main target was to find the alternative joining matter caused by permanently bumping costs of epoxide resin and its flammability. Presented paper deals with the influence of filling agent in geopolymer matrix (quantity of sand and its fractionation) on course of acoustic absorption coefficient and describes also the influence of thickness of geopolymer/sand mixture. The acoustic absorption coefficient α was defined within the range from 100 Hz to 2500 Hz. The results showed that both presented mixtures have specific sound absorbing properties – average value of coefficient with boarder range of effectiveness and high absorbing coefficient with narrow profile of effective frequencies.