Performance of biof oam polyurethane-urea/rice straw waste (Oryza sativa) as a noise reducer

Abstract

Noise is one of the common problems found in the metal processing industry. The noise that continuously occurs can influence the health of workers. The large number of workers who do not use Personal Protective Equipment (PPE) and pay less attention to work safety, resulting in them being exposed to high noise, for example, parts of production units that have an average noise intensity of 102.9 dBA/8 hours. The need of noise reduction materials for the metal processing industry is still very potent. Utilization of eco-friendly noise reduction materials in a wide frequency range cannot be fulfilled by the existing materials. This research aims to synthesize polyurethane-urea/rice straw waste (PUU/RSW) foam and to measure its performance as a noise reducer. Rice straw waste is used as an additive in a mixture of polyurethane-urea foam. The one-step method is used for the synthesis of PUU/RSW biof oam using with the composition of maleic anhydric (MAH) 0.1% (w/w), ethylene diamine (EDA) 1% (w/w), variations of polyethylene glycol/methylene diamine (PEG/MDI) (1/1), and rice straw waste with the variations from 0, 1, 2, 3, 4, to 5% (w/w). The characterization of biof oam structures was carried out using FUR. The effectiveness of the foam in sound absorption is tested by using the two-microphone technique according to the ASTM E-1050 procedure. The results show that physically biof oam products are medium-textured (sof t to hard), porous and brown with chemical groups identified C-H, C-O, O-H. Noise absorption test results show that PUU/RSW biof oam is effective as a noise-reducing material as it has a high absorption coefficient in the wide frequency range.