meriplast - agrobiobase · meriplast® shows full degradation after 36 days in aerobic fermentation...
TRANSCRIPT
Reveals the potential of cereals
19/08/10
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Tereos
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Meriplast®
A novel protein-based bioplastic
Revealing the potential of wheat proteins
Wheat gluten is unique amongst vegetable proteins due to its specific visco-elastic properties, which are notably essential for quality in bread making. Tereos Syral has developed a process which enables to maintain the visco-elasticity of wheat gluten into a novel flexible and elastic biomaterial.
• Pic
ture
s cre
dits
: Pat
rick
Bogn
er, s
hutt
erst
ock
• Dec
embe
r 201
1 • T
he in
form
atio
n m
entio
ned
here
in re
mai
n th
e pr
oper
ty o
f Ter
eos S
yral
or i
ts c
onta
ctor
s. A
lthou
gh T
ereo
s Syr
al u
ses r
easo
nabl
e en
deav
ours
to e
nsur
e th
e ac
cura
cy a
nd c
ompl
eten
ess o
f sai
d in
form
atio
n, T
ereo
s Syr
al w
aive
s all
liabi
lity
in re
latio
n to
thei
r use
by
the
addr
esse
e.
Sustainability
Meriplast® is 100% based on renewable raw materials (wheat and oilseeds such as rapeseed or sunflower) and 100% biodegradable. The production process is very mild and fully complies with the principles of green chemistry.
Mechanical and physical properties
Meriplast® has unique flexibility & elasticity properties. It shows a good resistance to torsion and folding. It is not soluble in water but a prolonged immersion in water will affect the materials’ mechanical properties.
Sensory
Meriplast® displays outstanding sensory properties. It has a very good touch, a good grip without stickiness, it is permeable and absorbs water. It has a pleasant cereal smell.
Safety
Meriplast® is not toxic when degraded in farmland soil. It does not burn in normal atmospheric conditions: it has a limited oxygen index (LOI) above 21% (22 and 26% for Meriplast® N60 and N50 respectively).
A novel flexible and elastic biomaterial
Meriplast® is a novel bioplastic entirely made from raw materials derived from agriculture and is fully biodegradable. This material has specific flexibility and elasticity properties, which makes it unique amongst the biodegradable and renewable materials currently available. Meriplast® is fully bio-based, it is both renewable and biodegradable.
ApplicationsThe targeted applications of Meriplast® are moulded objects for interior such as toys, leather imitation for office products (covers), design articles, pieces of furniture. Applications are still in the development phase.
ProcessabilityMeriplast® can be processed on standard rubber processing machinery (injection moulding, calandering).
The rangeDifferent grades that vary in extensibility and tensile strength can be produced. The material’s natural colour is light brown but it can be coloured into a wide variety of tints.
Why use Meriplast®?
Meriplast® life cycle
AgriculTurAl ProducTion
wheat oilseeds
coproduct coproduct
Te r e o s S y r a lPAT e n T e d P r o c e S S
Meriplast®
Bio-ethanol Bio-diesel
b i o d e g r A d AT i o n1 0 0 %Figure 1: The natural colour
of Meriplast® is light brown.
Figure 2: Prototypes of finished products made of Meriplast®
Mechanical properties
The mechanical properties of Meriplast® are similar to elastic materials such as natural rubber or thermoplastic elastomers up to 100% elongation. Ultimate tensile strength and elongation are however lower (Table 2).
A visco-elastic behaviour
Meriplast® exhibits a complex visco-elastic behaviour with dominant elastic features, as demonstrated by relaxation tests (Figure 6). The figure shows changes in the tensile modulus over time under a constant extension ratio of 100 %. The behaviour of the material is in between a purely elastic and a purely viscous material: the linear decrease on a double logarithmic plot has a slope of -0.13, compared to 0 for a purely elastic material and 1 for a purely viscous material.
Moreover, Meriplast® displays a unique, slow elasticity as shown by measures of residual elongation of the samples after removal from the testing machine (Figure 7). For example, after stretching the material to an elongation of 100% for 1h, the material retracts to 30% of its initial length after 30 minutes and to 4% after 7 days.
1,E+05
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trend line: slope = -0.13
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Figure 6: Relaxation test for Meriplast® N60 at extension ratio of 100%1,E+05
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trend line: slope = -0.13
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Figure 7: Residual elongation of Meriplast® N60 after relaxation test
Table 2: Physical and mechanical properties of Meriplast®
a According to ISO 527-2 type 5A, b Rubber Technology, Compounding and Testing for performance By John S. Dick Hanser, c Technical data sheet from API, d ASTM D 2240
Physical and mechanical properties
DensityHardness
(Shore A-15’’)d
Strength at 100% elongationa
Strength at break (MPa)a
Elongation at break (%)a
Meriplast® N60 1.30 69 2.3 4.5 350
Meriplast® N50 1.32 75 2.6 4.8 320
Natural rubber (thread)b - 70 3 30 500
API (TPE from APINAT)c - 65-83 2 – 4.5 10-14 700-800
Mechanical response to variations of humidity and temperature
Increasing temperature or humidity causes plastification of Meriplast®, hence decreasing elastic modulus.
Under standard ambient conditions (50% relative humidity and 25°C), the material has a moisture content of approximately 11% and a stress at break of 4.3 MPa. At a relative humidity of 70%, moisture content increases to 24% and stress at break decreases to 1.6 MPa (Figure 8). This is reversible when the material is put back to the initial conditions.Meriplast® is not designed for prolonged immersion in water. As an example, after a 24-hour immersion in water, the material adsorbs up to 1.5 times its own weight. Drying of the swollen material will result in the loss of mechanical properties in terms of flexibility and elasticity.
Temperature affects mechanical properties of Meriplast® in a steady way, with no sharp transitions. Dynamic mechanical thermal analysis shows that the material has a transition from glassy state (at -100°C) towards a rubbery state plateau (at 100°C), which occurs over a very broad range of about 200°C (Figure 9). For natural rubber, this transition typically occurs over 40 to 60°C. That makes Meriplast® unique amongst elastic materials.
Slow relaxation and resilience of Meriplast® also influence response to compression, which is different from that of rubber. Meriplast® N50 has a compression set value of 65% after a release time of 30 min, compared to 10% for natural rubber and
30% for SBR rubber. However, after a prolonged release time of 7 days, the material almost retrieves its original shape (Table 3).
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Figure 8: Influence of relative humidity on stress at break
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trend line: slope = -0.13
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Figure 9: Dynamic moduli (Storage Modulus, Loss Modulus and Tan Delta) as a function of the temperature for Meriplast® N60
Table 3: Compression set value (%) (ASTM D395 Method B type 1 for 24hr at 25°C)
compression time at 25°CMeriplast® N50 Meriplast® N60
after 30 min release after 7 days release after 30 min release after 7 days release
1 hour 31 1 25 <1
1 day 65 8 62 <1
2 days 67 10 59 3
1 week 77 32 80 37
Packaging and storageMeriplast® is available in 15 kg reels with endless strands of 13-14 mm diameter (Figure 3). Different packaging is available on request. The product should be stored in a cool, dry place with good ventilation.
Figure 4: Equipment used for testing Meriplast® processing
Figure 3: Meriplast® packaging
Processing conditionsMeriplast® is thermosetting and has a processing viscosity similar to uncured rubbers. Consequently, it can be shaped using traditional rubber injection technology, for example on REP machinery (REP International, 69960 Corbas, France) (Figure 4).
Recommended temperature settings are 60°C in the extrusion section, 70°C in the injection chamber and 140-150°C in the mould. Examples of moulded articles such as plates (120 x 120 x 2 mm) or conical frustums (60 and 47 mm for the diameters, 25 mm height) are shown in Figure 5. Typical mould shrinkage is 2.5%, as determined with a calibrated plate mould.
Conical frustum
Two plates obtained with one injection: one being injected in parallel and the other one by one point
Figure 5: Examples of moulded articles
Moulding temperature (°C) Moulding time (min)
Plate140 6
150 2
Conical frustum 140 10
Table 1: Optimal processing conditions for two moulded objects
Similarly to other natural materials such as leather or wood, Meriplast® adsorbs water but it is not soluble in water. Prolonged contact with water (e.g. dishwasher) should be avoided.
Meriplast® shows full degradation after 36 days in aerobic fermentation (according to ISO 14852 based on the modified Sturm test) and 50 days in farmland soil. Meriplast® and its
degradation metabolites are not toxic as tested by microbial inhibition tests.ISO 14852: Determination of the ultimate aerobic biodegradability of plastic materials in an aqueous medium - Method by analysis of evolved carbon dioxideDomenek S., Feuilloley P., Gratraud J., Morel M.H., Guilbert S. (2004) Biodegradability of wheat gluten based bioplastics Chemosphere 54: 551–559
Product stability and degradation
The company
Tereos Syral is the 3rd European starch producer and is the starch activity of the international agro-industrial group Tereos. Tereos Syral transforms 3 million tons of wheat and corn in its 6 European factories into 1,800,000 tons of starch and starch-based products, 180,000 m3 of alcohol and bioethanol, 200,000 tons of vegetable proteins, and by-products for animal feed. The firm has 1,280 employees and has a pro forma yearly turnover of 1.2 billion €.
The success of starch products is linked to their versatility and to their renewable as well as biodegradable nature. Current starch manufactures can already be described as bio-refineries. Fibre, protein and starch from the cereals are separated by mostly mechanical means and further transformed in specific lines combining a wide range of technologies: enzymatic or chemical hydrolysis and modifications, hydrogenation, refining, fermentation, drying, crystallisation.
Tereos Syral received the special award of R&D for Meriplast® at the Biowerkstoff-Kongress in Stuttgart in October 2009.
Zone Industrielle et PortuaireF-67390 MARCKOLSHEIMTel : +33 (0)3 88 58 60 60Fax : + 33 (0)3 88 58 60 [email protected]
19/08/10
CMJN
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Tereos
logo TEREOS Syral
- 100%
---
• Pic
ture
s cre
dits
: Pat
rick
Bogn
er, s
hutt
erst
ock
• Dec
embe
r 201
1 • T
he in
form
atio
n m
entio
ned
here
in re
mai
n th
e pr
oper
ty o
f Ter
eos S
yral
or i
ts c
onta
ctor
s. A
lthou
gh T
ereo
s Syr
al u
ses r
easo
nabl
e en
deav
ours
to e
nsur
e th
e ac
cura
cy a
nd c
ompl
eten
ess o
f sai
d in
form
atio
n, T
ereo
s Syr
al w
aive
s all
liabi
lity
in re
latio
n to
thei
r use
by
the
addr
esse
e.