Lightweight biodegradable porous poly(propylene carbonate)/carbon nanostructures nano/microcellular structures with enhanced foamability, good electromagnetic interference shielding, and low permanent strain

Abstract

Poly(propylene carbonate)/carbon nanostructures (PPC/CNS) composite foam with excellent comprehensive performance was successfully fabricated using supercritical carbon dioxide (Sc-CO2) as the physical foaming agent. Transmission electron microscope analysis revealed that the CNS was uniformly dispersed within the PPC matrix. This effective dispersion of CNS, coupled with enhanced melt strength, consequently facilitated the foamability of PPC/CNS composites. Remarkably, at a CNS loading of 3 wt%, the cell size of PPC/CNS composite foam reduced from micron to nanoscale dimensions, resulting in a cell density surpassing 1013 cell/cm3. Furthermore, the prepared PPC/CNS composite and its foams exhibited promising potential for applications in electromagnetic interference (EMI) shielding and sensor. For instance, by incorporating 3.0 wt% CNS, the EMI SSE reached 84.70 dB cm3/g after foaming, which exhibited favorable EMI shielding characteristics. Moreover, the composite foam exhibited excellent resilience and stability, led to a reduction of residual strain to less than 11 % after 10 cyclic compression tests.