1Cellular polymers constitute an important field of investigation due
to their unique properties as shock absorbers and thermal or acoustic
insulators. The knowledge of the wetting properties of these materials
is important in applications where adhesion or weathering behavior ar
e an issue. In this study, cellular polyurethane polymers were used to
investigate the effect of the cellular structure on the wetting prope
rties. The polymeric substrates were analyzed by scanning electron mic
roscopy and the wetting properties were studied by goniometry. The con
tact angles of water and diiodomethane were measured as a function of
time and the surface tension of the expanded polymers was evaluated by
the geometric and harmonic mean methods. It was found that the wettab
ility and the surface energy of the cellular polymers increase as the
density decreases. (C) 1997 John Wiley & Sons, Inc.