Enhanced thermal conductivity of PP hybrid films induced by filler orientation and laminated structure

Currently, polymeric composites with good thermal conductivity and simple preparation method are in the rapid increment of demand. In this work, polypropylene/graphite/graphene films (PP/Gr/G-3, 8 layers) with high thermal conductivity were developed by a multi-folding and hot-pressing strategy. The PP/Gr/G-3 composite films exhibit highly in-plane thermal conductivity of 17.23 W m −1 ·K −1 (TCE = 99.19%, compared with the PP/Gr/G-0 films). This high thermal conductivity is mainly due to the well-oriented structure of fillers and tightly laminated microstructure in composite which are induced by the facile and scalable multi-folding method. Additionally, the PP/Gr/G-3 composite films demonstrate enhanced mechanical properties with the tensile strength of ~ 26.26 MPa and toughness of ~ 0.52 MJ m −3 . The effective fabrication strategy proposed in this work could be valuable for improving the thermal management properties of polymeric composites.