Design of Experiment for Sound Absorption Materials of Microporous Polymer

This study is to explore the Design of Experiment (DoE) method by mean to analyse the optimum settings for any related processes being used in the manufacturing process of microporous Polyurethanes (PUs) foams. The microporous interconnected PUs foams were prepared in a cylindrical shape with 100 mm and 28 mm diameter in respect to low (0-1500Hz) and high (1500-6000Hz) frequency absorption level as well as the sound absorption coefficient (α). Thus, the DoE method was used to optimize the fabrication conditions of PU foams with predetermined operatory conditions with four (4) input factors of X1, X2, X3 and X4. These factors are monomer type (X1), filler ratios (X2), filler type (X3) and sample thickness (X4) (10 mm, 20 mm and 30 mm), which then gives significant trends in morphological responses such as main pore size (V1), interconnected pore (V2), strut thickness (V3) and frequency responses on sound absorption coefficient (α), (V4) for PUs foams. The results show that the sound absorption coefficient at low frequency increased when increasing the size and ratios of filler. With the increasing of thickness of the samples, shows the ability to increase the sound absorption coefficient of microporous polymeric foam at higher frequency level.