Issue 01/2016

Automotive
Smart bioplastics for
automotive applications
By:
Francesca Brunori
Advanced Development Engine Systems
Röchling Automotive
Laives, Italy
Röchling Automotive reports promising results on the development
of automotive parts made of Plantura PLA
based biopolymers.
In collaboration with Plantura Italia Srl (Italy) and Corbion
Purac (The Netherlands), Röchling Automotive is working
towards greener products offering similar or enhanced
technical functionality.
Plantura has a CO 2
equivalent emission of approximately
0.5 tonnes for each ton of produced raw material. This is
around 70 % lower than PP, and close to 90 % less than PA6.
There are currently four standard grades available that are
suitable for low to medium demanding automotive underthe-hood
applications and – using the glass fiber filled
grade – in underbody applications. The talc filled standard
grade, as well as natural fiber filled grades, are suitable for
automotive interior applications. As these different standard
grades, which boast a biocontent of up to 95 %, can be finetuned
to meet specific customer needs and final application
requirements, the material has already been used in series
production in sectors other than the automotive market. The
compounds can be processed and recycled with conventional
plastics processing and recycling technologies.
In comparison to standard PLA, Plantura showed significant
improvements in thermal stability and chemical resistance.
Long term thermal stability was tested according to thermal
cycle tests performed from -40 °C to 140 °C according to an
OEM’s specification. When tested at temperatures as low as
-30 °C, the material demonstrated an outstanding impact
resistance for shockproof parts, showing that Plantura 30 %
GF can offer values of up to 50 % higher Charpy impact
strength compared to a PA6 GF+M30. The materials also
exhibit excellent hydrolysis resistance.
Prototype filter boxes (cf. fig. 1) as well as interior parts
were tested according to the OEM’s complete specifications,
with very promising results
The use of Plantura for the air flaps (fig. 3) of an Active Grille
Shutter (fig. 2) was investigated and the initial results bode
well for the future. The injection molded Plantura component
has a higher stiffness compared to the component produced
with the standard material (PA6 GF30). Because of this,
deflection is lower during use, which can be used to reduce
air leakage. Moreover, thanks to the lower shrinkage of the
material, it is also possible to reduce the deformation of the
final component. Another big advantage to using Plantura for
this application is that the dimensional stability will increase
over the lifetime of the component, due to the fact that no
humidity is absorbed. The scratch resistance behavior of PLA,
an extremely important aspect when it comes to aesthetic
components in general, and in this case for aesthetic Active
Grille Shutters In particular, is well known and taken into
consideration in the Plantura formulations.
The continuous development of the material has led to
higher, and increasingly interesting cost efficiency. With its
significant contribution to an improved CO 2
balance, Plantura
could become an important concept in the automotive world.
www.roechling.com
Fig. 1: Filter box made of Plantura 30 % Wood Fibers
Fig. 2: Assembled Active Grille Shutter
Fig. 3: Air flaps of Active Grille Shutter made of
Plantura 30 % Glass Fiber reinforced
bioplastics MAGAZINE [01/16] Vol. 11 15