Thermoplastic polyurethane-graphene nanoplatelets microcellular foams for electromagnetic interference shielding

TL;DR

This study develops microcellular thermoplastic polyurethane/graphene foams using batch foaming and supercritical CO2, demonstrating effective electromagnetic interference shielding with significantly lower graphene content than previous materials.

Contribution

First report of TPU/graphene microcellular foams produced via batch foaming with supercritical CO2, showing comparable EMI shielding at lower graphene loadings.

Findings

Effective EMI shielding in the THz range.

Comparable shielding with 1 wt% graphene to higher loadings in literature.

Successful dispersion of graphene nanoplatelets in TPU matrix.

Abstract

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%).