Biobased porous acoustical absorbers made from polyurethane and waste tire particles

GUILLERMO SOTO; ANTHONY CASTRO; NILDA VECHIATTI; F. IASI; ALEJANDRO ARMAS; NORMA E. MARCOVICH; MIRNA A. MOSIEWICKI

POLYMER TESTING

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2017 vol. 57 p. 42 - 51

0142-9418

The production of flexible polyurethane foams (FPF) with good acoustical performance to control sound and noise andincorporating bio/recycled raw materials is an interesting alternative to conventional acoustic absorbent materials. In thissense, biobased polyols like glycerol (GLY) or hydroxylated methyl esters derived from tung oil (HMETO) as multifunctionalpolyols, and waste tire particles (WTP) as fillers of low thermal conductivity and good capability for acousticalabsorption, are prospective feedstocks for FPF preparation. In this work, FPF were prepared by adding different amountsof these components to a formulation based on a commercial polyether polyol. Results of scanning electron microscopy(SEM) analysis, compression tests and normal-incidence sound absorption coefficient (αN) measurements are presentedand discussed. The addition of WTP or GLY to the commercial formulation enhanced both the modulus and yield stressof the obtained FPF in all cases. Moreover, a high recovery of the applied strain (>90%) was attained 24 h after the compressiontests. On the other hand, the normal-incidence sound absorption coefficient, αN, reached high values mostly atthe highest evaluated frequencies (αN ∼0.62?0.89 at 2000 Hz and αN ∼0.70?0.91 at 5000 Hz). SEM micrographs revealedthat the foams obtained present a combination of open and closed cell structure and both the modifiers and particles tendto decrease the cell size.