Individual treatment of patients
Biomaterials for 3D Printing Technologies
Evonik has been the world's leading manufacturer of smart biomaterials for additive manufacturing technologies for more than 20 years. The specialty chemicals company offers the industry's most extensive portfolio of 3D-printable biomaterials for medical technology, which can be used to manufacture medical device parts designed for temporary and permanent body contact. In addition to PEEK-based filaments of the VESTAKEEP® brand, the portfolio includes the RESOMER® line of bioresorbable filaments, powders and granules for implantable medical devices.
No other application field showcases the possibilities of 3D printing better than medical technology. Evonik specifically provides biomaterials of biological as well as non-biological origins. The RESOMER® material is a biodegradable biopolymer and VESTAKEEP® is a biostable polymer. Both materials can be processed by 3D printing, RESOMER® via SLS, FFF and Freeform printing and VESTAKEEP® via FFF or Freeform printing.
Material extrusion
The material in this process is a polymer filament that is supplied by a roll. A print head liquefies the material in a manner similar to a hot-melt glue gun. As a result, components are created layer by layer out of liquid polymer. A second print head adds support material, which it deposits into cavities and at overhangs, for example, because the component has to be supported in these areas during the printing process. This support material is removed after the component is finished.
Fused Filament Fabrication (FFF) 3D printing technology meets the requirements of individual parts, while being extremely material-saving and capable of processing the high-performance polymer PEEK. Using FFF, the material is melted in filament form, a kind of plastic strand, through the printhead using high temperatures of up to 500 °C and applied in different layers to the desired component. Decisive for the component quality is the controlled solidification process of the semi-crystalline plastic.
Some methods melt or soften the material to produce material layers. Besides the deposition of single elements in the 3D structure, fast and continuous deposition of 1-dimensional structures within the 2D slayer is possible in this technology. In fused filament fabrication, also known as fused deposition modeling (FDM™), the model or part is produced by extruding small beads or streams of material that harden immediately wile cooling to form layered structures. A stream or filament of thermoplastic, a metal filament, or other (composite) material is fed into an extrusion nozzle head (3D printer extruder), which liquefies the material and turns the flow on and off. Meanwhile printers with simultaneous multi material deposition are available, also allowing support structures for complex geometries.
OUR READY-TO-USE FILAMENTS
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Product |
Technology |
Properties |
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FFF |
Biodegradable medical grade filament |
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FFF |
Implant grade PEEK filament |
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FFF |
Test implant grade PEEK filament |
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FFF |
Medical care grade PEEK filament |
Powder bed fusion
A powder is deposited layer by layer and fused at the places where a component is to be created. Depending on the method in question, this is either done by a laser (LS) or an infrared light (Multi Jet Fusion™/MJF, High Speed Sintering/HSS). In the second variant, an inkjet printer prints a mostly black marking on the places that are to be fused. The black areas heat up faster than the unmarked areas. The finished component is then taken from the powder bed.
The specialty chemicals company is a world leader in the production of polyamide 12 powders (PA 12), which have been used in 3D printing for over 20 years. The development of the flexible high-performance powder expands Evonik’s existing product portfolio of synthetic materials for 3D printing. Evonik produces the powder materials at its largest global site, the Marl Chemical Park.
Evonik had already delivered the first polymer powder material for the additive manufacturing market - SLS technology - in 1996, thus setting standards that currently apply to 3D printing of plastic materials.
The principle of additive manufacturing using selective laser sintering
Selective laser sintering is based on the principle of the layer-wise build-up of a structure by combining powders to form a part. In general, the process can be characterized as follows:
- specification of a three-dimensional model in the form of CAD data
- no use of molding tools
- generative build-up; molding occurs not by removal of material, but by applying itany desired geometry
- offers freedom of design
Evonik has many years of experience in developing and processing products that lend themselves specifically to new 3d printing processes. Based on CAD data sets, 3d printing generates complex components through the layerwise application of polymer powders, filaments, fluids, binders or other suitable materials.
The principle is always the same: A material is laid down layer by layer. In practice, however, a wide variety of processes lead to the same result. One of the most important processes is selective laser sintering (SLS). Here, a powder is melted by means of a laser, layer by layer. This produces very precisely detailed and robust components made of either plastic or metal.
OUR READY-TO-USE POLYMER POWDERS
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Product |
Technology |
Class of material |
Properties |
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SLS |
Bioresorbable polymer |
Biocompatibel |
Since 2019, Evonik and BellaSeno have worked together to commercialize 3D-printed, resorbable implants using Evonik’s next-generation RESOMER® biomaterials. Evonik is supporting BellaSeno with material selection and customized materials to create patient-specific, resorbable scaffolds.
This white paper details a landmark case at Hannover Medical School where a patient specific scaffold manufactured by BellaSeno, leveraging Evonik’s RESOMER® biodegradable polymer platform, facilitated the successful reconstruction of a 14 cm segmental radius bone defect.
Want to learn more about Evonik's capabilities in the field of additive manufacturing?
With our medical device competence centers around the globe and a strong product portfolio we are well equipped to support you across various process technologies.
Contact us to let our process experts consult you and profit from more than 30 years of application know-how in the field of medical devices.
