Acoustic performance of corn husk fiber (Zea mays L) waste composite as sound absorber with latex adhesive

Abstract

The use of corn husk waste as a sound absorber material with latex adhesive presented in this paper. The acoustical performance measured by using two microphone impedance tube refers to the ASTM-E1050 standard for transfer function-based sound absorption measurement. The composite made of both treated and untreated corn fiber with mass fraction variation of 30% and 50% and the thickness are 2 mm and 4 mm respectively. Treated corn fiber soaked in 5% Sodium hydroxide (NaOH) solution for two hours before it rinsed with the fresh water and dried in open air. The test specimen produced manually. Treated and untreated corn fiber were put separately in the different tray and sprayed with a certain volume of a latex according to the mass fraction variation until the whole fiber completely fitted in the tray before it pressed manually and dried in open air. The similar process has done for both specimens with a thickness of 2 mm and 4 mm. It found that the untreated corn husk fiber (CHF) based composite has a better sound absorption performance compared to the treated one. As the specimen tested for cavity backed structure the sound absorption performance shifted to lower frequency band according to the stiffness of the composite layer and its oscillation increase the viscous damping effect accordingly.