The research area for additive plastics recycling was opened in 2020. We have numerous additive manufacturing systems, a complete recycling chain for thermoplastics and testing technology for research projects and customer orders. In addition to mechanical testing, we use various 3D scanners and a 3D profilometer to evaluate print quality (see Measuring and testing technology).
We are also investigating how additive manufacturing systems can be integrated into existing process chains.
3D printer for plastic filament and granulate

In the research area, we use additive manufacturing systems from various manufacturers, in different price ranges and with individual strengths.
The following printers are currently in use:
- Ultimaker S3
- Ultimaker S5
- innovatiQ X400
- Prusa MK3S+
- Anycubic i3 Mega
- Tumaker NX Pro Dual
We use 3D printers that can be adapted and further developed in research and development projects, as well as printers that are suitable for use in small and medium-sized enterprises (SMEs).
The majority of our printers work on the principle of Fused Filament Fabrication (FFF). They produce printed products by applying molten plastic layer by layer. We can process both filament and granulate. The materials that can be used include not only standard plastics such as PLA and PETG, but also engineering plastics such as polyamide with processing temperatures of up to 300 degrees Celsius.
A fully glazed rack protects the printers in our research area from dust, draughts and other environmental influences, thus ensuring stable, reproducible printing processes. The enclosure also serves as noise protection. The exhaust air is filtered through activated carbon and fine particle filters.
We provide our customers with manufacturer-independent advice on the selection of suitable systems for their individual areas of application. We are also able to develop printers ourselves according to our customers' requirements.
Industrial printer X500PRO

The X500PRO from German RepRap GmbH, modified by us, allows higher processing temperatures of up to 450 degrees Celsius. This makes it possible to process materials whose processing temperatures are too high for most conventional 3D printers, such as PEEK, PEKK, PEI and polyamide.
In order to be able to use the industrial printer for research, we have expanded it with its own control system. This allows more detailed settings and thus enables improved process control and monitoring of the printing process.
During the printing process, we monitor and control the temperatures - in the print chamber, on the print head and in the cooling air - as well as the acceleration of the print head, the filament diameter and other parameters.
In-house development: 3D printer for XXL components

We have designed and manufactured an additive manufacturing system with a cubic meter of installation space at IPH. It enables the production of XXL components with dimensions of up to 1,000 millimetres in length, 1,000 millimetres in width and 1,000 millimetres in height.
Both plastic filament and granulate can be processed with the 3D printer. Nozzles with a diameter of up to 5 millimeters allow the time-saving production of very large components. Finer nozzles are used for details. Thanks to the modular tool changing system, the print head can be changed with a single click.
The XXL 3D printer is constantly being further developed and adapted to requirements. In the future, it should be possible to manufacture new products directly from recycled materials. Printing with two nozzles simultaneously is also planned - for the optimum balance of printing speed and level of detail.
Plastic recycling for additive manufacturing

With the JARVIS Mini Shredder from QiTech Industries GmbH, we can process plastic waste into granulate to produce new components.
If the recycled material is to be used in filament 3D printing, it must first be dried, then melted in an extruder and wound onto a spool. These intermediate steps are not necessary for 3D printers that can process granulate. They can produce new components directly from the regrind.
In the Additive Plastics Recycling research area, we have implemented a complete process chain to process plastic waste for 3D printing. We are currently developing a universal shredder at IPH that can shred larger quantities of plastic waste - for example yoghurt pots or screw caps made of polypropylene (PP).
Surface treatment of 3D-printed components

We use the Zortrax Apoller for the post-processing of additively manufactured components. The device smoothes the surface of FFF 3D-printed components so that they achieve the surface quality of injection-molded components.
With Smart Vapor Smoothing (SVS), solvents such as acetone are atomized inside the device and smooth the component surface. The temperature, pressure and concentration of the solvent vapors are controlled automatically and smartly.
Universal testing machine

We test the strength of additively manufactured components in tensile tests using the Inspekt Duo universal testing machine from Hegewald & Peschke Meß- und Prüftechnik GmbH.
By using standard-compliant samples, we can characterize materials mechanically.
For samples made from recycled material, we can investigate after how many recycling cycles the material properties deteriorate. The universal testing machine is therefore an important tool in the research and further development of additive plastics recycling.
In addition, we can also carry out hardness tests (HRC and HB) to assess material properties.
Pendulum impact tester

Pliable or brittle? We test the ductility of 3D-printed specimens using the HIT5.5 pendulum impact tester from ZwickRoell GmbH & Co. KG.
A specimen is clamped into the device. In the so-called notched bar impact test, a hammer strikes the specimen in a pendulum motion. The residual energy of the hammer is measured and allows conclusions to be drawn about how much energy the sample has absorbed.
If the material has a high ductility, it absorbs a lot of energy and bends without breaking. If the material has a low ductility, it absorbs little energy and splinters.
Moisture analyzer

With the KERN DBS 60-3 moisture analyzer, we can measure the moisture of granulate and filament.
The moisture content of the material plays a major role in the quality of additively manufactured components. It therefore makes sense to determine the moisture content before the production process - especially for granulate or filament that we have produced ourselves in the research area for additive plastics recycling, but also to check the manufacturer's specifications for purchased filament or granulate.