Two new production resins are available for 3D printing: one from 3D Systems is a thermoset that thinks it’s a thermoplastic and another from Carbon is a hybrid that’s 30 percent biomaterial, the company’s first resin with a reduced carbon footprint.
Carbon, Redwood City, Calif., partnered with DuPont Tate & Lyle Bio Products to use Susterra propanediol, a 100 percent bio-based material made from corn sugar, in its RPU 130 resin. Compared to petroleum-based alternatives, Susterra propanediol produces 48 percent less greenhouse gas emissions and uses 46 percent less nonrenewable energy from raw material to manufactured product.
Jason Rolland, senior vice president of materials for Carbon, said well-known problems with plastics spurred his company to reduce its carbon footprint and help solve society’s plastic waste problem.
The company is also working on recyclable resins as well as partially plant-derived materials, Rolland said. He thinks many industries are looking for plant-derived raw materials as an alternative.
RPU 130 performed well in long-term heat stability testing, Rolland said. Subjected to 400 continuous hours of environmental aging at 85°C (185°F), it retained greater than 80 percent of its mechanical properties, including impact strength, a characteristic critical for use in automotive parts, he said. It also retains 75 percent of its tensile and impact strength properties after a PV1200 test, a standard developed by Volkswagen to evaluate material durability for climate cycling at elevated heat and humidity.
RPU 130’s elongation at break is 50 percent and it has a tensile strength of 35 MPa, a tensile modulus of 920 MPa, a heat deflection temperature of 119°C (246°F), and Gardner Impact strength value of greater than 30 J.
Meanwhile, at 3D Systems, Rock Hill, S.C., “We’ve just cracked the code on what we believe to be the first direct print photopolymer that’s exhibiting thermoplastic behavior,” said Patrick Dunne, vice president, advanced applications development. “If we want to transition from rapid prototyping to additive manufacturing material, properties are key.” To meet high production rates, parts need to be tough and ductile without complex oven cycles.
The company’s new Figure 4 PRO-BLK 10 is suitable for small, black, plastic parts such as motor housings, connectors, snap-fit or automotive interior parts.
The material begins to show properties of thermoplastic parts, such as elongation. The elongation at break of Figure 4 PRO-BLK 10 is 12 percent. Finished parts have a tensile strength of 63 MPa and a tensile modulus of 2,320 MPa. They’re heat-resistant, with a heat deflection temperature of 70°C (158°F).
For now, Figure 4 PRO-BLK 10 is available only in black, customers have asked for white, clear and colors, and those suggestions are under consideration, according to the company.
The printed parts come out of the curing chamber after a single cycle with a good surface finish and need minimal post-processing.