Abstract

In this study, we investigated the changes in the structural and mechanical properties of polyurethane (PU) induced by blending it with poly (ethylene glycol) (PEG) of two different molecular weights, viz., PEG 8000 and PEG 3350, at different molar ratios as soft segments. The properties of the resulting PU/PEG specimens were characterized using dynamic mechanical analysis, differential scanning calorimetry, etc. As the content of PEG 8000 increased, the Young’s modulus of the blend increased by 124.8%, and its degree of crystallinity increased by 12.37%, whereas the degree of phase separation decreased by 31%. Furthermore, the PU/PEG specimens with a mixture of PEG 8000 and PEG 3350 exhibited broader and higher tan δ peaks compared with those of the specimens with PEG of a single molecular weight. These results indicate that the use of PEG mixtures in PU leads to superior sound absorption.

Keywords: Polyurethane, PEG, crystallinity, phase separation, loss factor