Novel electrically conductive composite filaments based on Ag/saturated polyester/polyvinyl butyral for 3D-printing circuits

Novel composite filaments with high electrical conductivity and adhesion were fabricated through a film transition technique based on two-dimensional silver powders, saturated polyester (SP) and polyvinyl butyral (PVB). The film transition technique and flow-induced orientation in the flow field resulted in the two-dimensional silver powders in the Ag/SP/PVB composite filaments being well ordered, which helped in obtaining the low volume resistivity of the composite filaments. When the Ag loading was 55 wt%, the volume resistivity of the Ag/SP/PVB composite filaments decreased to 3.14 x 10(-4) Omega cm. In addition, the Ag/SP/PVB composite filaments possessed thermal stability up to 340 degrees C and microhardness beyond 18.30 HV0.2. The 3D-printed samples demonstrated good adhesion (<= level 2) to paper, PET and alumina ceramic substrates. Considering that a high electrical conductivity and adhesion can be obtained simultaneously, the Ag/SP/PVB composite filaments might be potential candidates for 3D-printing circuits in a rapid and green way.