Influences of Rice Hull in Polyurethane Foam on Its Sound Absorption Characteristics

In this article, rice hull (RH) was used in the moulding of polyurethane (PU) foam system. The article analyzed the participation of RH in the chemical reaction of PU synthesis with Attenuated Total Reflection-Fourier Transform Infrared spectroscopy method. Besides, the influence of RH on the formation of pore structure along with the acoustic performance such as sound impedance rate, acoustic reflection factor, sound absorption coefficient, and transmission loss of the products were studied with the Transfer Function Method. The results indicated that RH significantly influenced the uniformity of pore diameter in PU foam. As the content of RH increased, the sound absorption peak shifted toward lower frequency region. And the sound absorption coefficients increased till a threshold value of RH content. POLYM. COMPOS., 34:1847-1855, 2013. (c) 2013 Society of Plastics Engineers