Issue 02/2017

From Science and Research
This article is focused on the development of
new packaging for vegetables based on the
following steps:
• Extraction of fatty alcohols from fermentable sugars that
can be found in vegetable waste (fruits, such as melon
and watermelon, and vegetables, such as cucumbers,
peppers and courgettes).
• Chemical modification of commercial biopolyesters by
grafting fatty alcohols onto their polymer chain by means
of reactive extrusion in order to improve their elastic
properties.
• Obtaining new biopolyesters suitable for the extrusion of
nets and shrink film.
• Currently, the project has exceeded its one third
development baseline schedule; during this first period,
the researchers have achieved the following:
• Formulation of the definition of the material
requirements and characteristics to be met by both
packaging types.
• Chemical modifications have been carried out in PLA
at laboratory level using commercial fatty alcohols with
different purities.
In this step, PLA was modified by using commercial oleic
alcohol with two different purities; high purity (80 – 85 %)
and low purity (60 %). Both alcohols were grafted onto the
PLA polymer using direct grafting radical reactions.
A test was performed in which the radical agent was
optimized, on the basis of the percentage used in the
reaction, the percentage of oleic alcohol employed, as well
as the temperature and the reaction time. Once the reaction
conditions had been optimized with the commercial
alcohol, the same reaction was performed using oleic
alcohol obtained through the fermentation of sugars from
vegetable waste. A summary of the results is shown in the
following table:
c) Chemical modifications at laboratory level
Purity of the oleic
alcohol
Commercial
60 %
Commercial
80 – 85 %
Oleic alcohol percentage
employed in the
reaction (%)
Grafting
reaction
efficiency (%)
1 82,5
2 99
3 95
1 71
2 91
3 70
a) Shrink Film Requirements
b) Packaging Nets Requirements
Shrink film for cucumber
Processable material produced
through
Blown Film Extrusion
Film with good transparency.
Packaging nets for green beans and garlics
Processable material produced using
Extrusion Melt Spinning technology
• Garlic: Oriented nets
• Green Beans: not oriented nets
In this step, the researchers developed a route to graft
oleic alcohol onto the PLA polymer. Using this methodology,
the efficiency of the grafting reaction using 2 % of fatty
alcohol was higher than 90 % in both cases. Additional trials
using the oleic alcohol derived from fermented vegetable
waste, are under development.
Future steps:
In the second part of the project, this chemical
modification process will be scaled up from laboratory to
pilot plant level. Both products (shrink film and packaging
nets) will be manufactured. The packaging characterization
will continue and the validation of both types will start,
bearing in mind their functionality. At the end of the project,
the scaling up of new bio-compounds and the production of
final products will be also carried out.
Partners
This Spanish project, coordinated by La Union, is being
carried out by a consortiumof six companies: La Unión,
Neol, DOMCA, Torres Morente, Ecoplas and Morera y
Vallejo.
These companies have subcontracted four research and
development centers to perform a number of tasks: CIDAF,
Las Palmerillas, Tecnalia and AIMPLAS, who is also in
charge of the technical coordination of the project.
Acknowledgement
This project has received funding from INNTERCONECA
(ITC-20151281) a programme funded by CDTI (Spanish
Government).
www.aimplas.es
bioplastics MAGAZINE [02/17] Vol. 12 41