There are not many material options for electrostatic discharge (ESD) applications available to process using additive manufacturing systems. The majority of these materials are thermoplastic filaments to use in material extrusion, fewer options are offered for laser sintering machines and there is a distinct lack of static dissipative radiation curable resins. The deficiency could be due to the high-level loadings of the filler needed to provide desired conductivity levels, which inhibits curing and necessitates constant mixing of the resin in the vat.
Mechnano has developed a radiation curable formulation that offers static dissipative properties to fabricated components without the requirement for continuous mixing of the resin. The technology is based on the integration of the untangled functionalized carbon nanotubes (MECHT) into the radiation curable feedstock. In the preliminary trials, Mechnano modified off-the-shelf resin and attained the surface resistivity in the range of 1×106 to 1×1010 ohm per square. It then formulated a masterbatch based on the urethane methacrylate oligomer for producing static dissipative resins of various compositions. One of these compositions was formulated and tested for surface resistivity and mechanical performance. Results showed that addition of MECHT offered surface resistivity in the static dissipative range and did not compromise the mechanical performance of the components. In fact, tensile strength and impact resistance increased 8% and 10%, respectively, compared to the virgin resin. These findings demonstrate that a radiation-curable resin can be ESD compliant while having improved mechanical performance.
- Obtain the working knowledge of carbon-nanotube dispersions in photopolymer resins
- Apply and connect learned concepts to the photopolymer resin design for static dissipative performance
Identify the key features and characteristics of carbon nanotubes and explain how these properties affect the performance of the final part