Shear-induced alignment in 3D-printed nitrile rubber-reinforced glass fiber composites

Nitrile rubber composite with aligned glass fibers (GFs/NBR composites) were prepared by direct-ink-writing (DIW) technology for application in flexible thermal management of electronic equipment.The alignment and orientation (0°, 45° and 90°) of glass fibers was precisely tuned by shear force field and 3D printing direction. Furthermore, the effect of print direction on the mechanical properties , thermal conductivity and heat dissipation performance were investigated. The tensile strength (1.78 MPa) and thermal conductivity (1.2 W m −1  K −1 ) of GFs/NBR composites with a 90° orientation was improved to be 149.6% and 300% compared to the composites with disordered orientation, respectively. The temperature of LED device and computer’ CPU covered with GFs/NBR composites with a 90° orientation was reduced by ca. 8.1 °C and 4.1 °C, respectively. The study confirmed the formation of GFs/NBR composites with controlled alignment and orientation for various applications.