  The incorporation of graphene-related materials as nanofiller can produce
multifunctional foams with enhanced specific properties and density reduction.
Herein we report on the preparation of microcellular thermoplastic
polyurethane/graphene foams by batch foaming. Solution blending was first
adopted to disperse graphene nanoplatelets (GNP) in the elastomeric matrix.
Then, a foaming process based on the use of supercritical CO2 was adopted to
produce the microcellular TPU/GNP composite foams with graphene content up to 1
wt%. The EMI shielding behaviour of the TPU/GNP foams has been assessed in the
THz range, and has revealed their potential in comparison with other
graphene-filled foams presented in the literature, that exhibit similar
specific shielding effectiveness but at much higher content of graphene-related
materials (10-30 wt%).
