Sustainable Composites Based on Recycled High-density Polyethylene/mica

Abstract Composites based on recycled high-density polyethylene (rHDPE) and muscovite mica, with different rHDE/mica ratios (100/0, 95/5, 90/10, 85/15 and 80/20, weight percentage) were prepared in an internal mixer with roller-type rotors at temperature of 170 ºC for 10 minutes. The materials obtained were characterized by tests of density, Shore hardness D and melt-flow index, along with infrared spectroscopy, thermogravimetry, differential scanning calorimetry and scanning electron microscopy. The hardness analysis confirmed the action of mica as a reinforcing load in the matrix, but this effect stabilized at around 15%. The TG analysis showed that the 85/15 composite presented slightly better performance than the 80/20, indicating that mica, up to 15%, caused disorganization of the polymer structure instead of reinforcing it. The DSC results revealed that the composites had slightly lower melting temperatures than the matrix. The FTIR spectrum indicated there was no chemical interaction between the rHDPE and mica.