bioplasticsMAGAZINE_1406

3D printing
Extruding of the thermoplastic Bio-PU out of a 0.5 mm nozzle
(Photo: Merseburg Univ. Appl. Sc. /D. Glatz)
Rapid prototyping methods
for bio-based plastics
Merseburg University develops procedures and devices
Today rapid prototype parts are required in all areas and
are vitally important for the product development process.
The wide range of Rapid Prototyping (RP) procedures
and thus the choice of the materials to be used are limited.
FABIO (FAbrication of parts with BIOplastics) is an R&D
project funded by the German Federal Ministry of Food and
Agriculture (BMEL) through its project management agency,
the Agency for Renewable Resources (FNR). As part of this
project, scientists from Merseburg University of Applied Sciences
(Merseburg, Germany) have developed a test facility
for rapid prototyping, using the so called fused extrusion
prototyping (FEP), for processing bioplastics. This technology,
which is considered important for the industry, could not be
used so far with biopolymers.
Specific values for the processing of the bioplastics were
determined by carrying out different analyses. The extrusion
unit was developed to enable processing of all sizes of
granulates. Temperature ranges are adjustable up to 300 °C.
Particular attention was paid to the extruder feeder,
the optimum melting and discharge of the biopolymers
considering the influences of the cylinder and screwconstruction,
screw clearance, screw speed and head and
nozzle geometry. The necessary cooling facilities were also
taken into consideration.
Different settings were tested using selected bio-plastics
and any deficiencies disrupting the process could be remedied.
Some complex and individual parts for the internal design of
the equipment were produced on RP machines, belonging
to the university. The rack could be provided with inside
superstructures, among other things, changing devices,
a heating system, a cooling system, a granulate material
supply, a construction platform, and procedural units in an
X-, Y-, Z-direction. The interaction of control mechanisms and
software could be tested, irrespective of the materials used.
The implementation of FABIO technology is imminent.
FABIO technology makes it possible to choose from a wide
range of thermoplastic granulates such as Polyamide,
Polyhydroxybutyrate, Polyurethane, Polylactide and starch.
After successful completion of the project, the aim is to take
the innovative idea, which was a spin-off from Merseburg
University of Applied Sciences, and turn it into a service
platform for prototype parts.
Other topics this service platform for rapid prototyping
with bioplastics will deal with are PSP (Photo Sensitive
Polymerisation of thermoset materials) and material
modifications for the SLS process (Selective Laser
Sintering). MT
www.hs-merseburg.de
Info:
The complete final report (German
language only) and a short project
description can be downloaded from
www.bioplasticsmagazine.de/201406
bioplastics MAGAZINE [06/14] Vol. 9 23