Study on thermal and dielectric performances of polyoxymethylene/thermoplastic polyurethane/multilayer graphene composites

Polyoxymethylene (POM)/ Thermoplastic Polyurethane (TPU) / Multilayer Graphene (MLGN) composites were prepared by mechanical processing using twin screw extrusion, and their thermal and dielectric performances were studied. The results show that MLGN can promote the decomposition of pure POM, but the thermal stability of POM can be greatly improved after adding TPU. MLGN has nucleation effect and can increase the crystallization temperature of POM. The heat distortion temperature of POM/TPU/MLGN composites increases with the increase of MLGN. The dielectric constant of POM/TPU/MLGN composites increase with the increase of the content of multilayer Graphene. At a content of about 9%, the dielectric constant of the composite material sharply increases, indicating the occurrence of a percolation channel. The dielectric constant of POM/TPU/MLGN composites is bigger and the dielectric loss factor is smaller at lower frequencies, and the dielectric constant is smaller, and the dielectric loss factor is bigger at higher frequencies.