Acoustic and thermal study of coconut fiber agglomerated with cassava starch

In this work, a thermal and acoustic study of specimens made from coconut fiber agglomerated with cassava starch is carried out. Sound absorption was measured in a transmission tube according to ISO 10534-2: 2001, in order to obtain the sound absorption coefficient (α). In addition, procedures described in ASTM E2611–19 were implemented to determine the sound transmission loss (STL). The results demonstrate the capacity of the tested specimen as a sound absorber, with absorption coefficients greater than 70% for a considerable range of frequencies starting at around 1000 Hz and above. Similarly, the thermal study of the material based on ASTM C-177 indicates an average thermal conductivity coefficient of 0,174 W/m.K, in a range of inlet temperatures between 52°C and 137°C, confirming that it has qualities that are similar to good thermal insulators, although still not comparable to some industrial materials.