| Sumario: | The feasibility of making bioplastics out of oil cake from Crambe Abyssinica, Brassica
Carinata and Brassica Napus (Rapeseed) was studied in order to produce added value for
these by-products. The materials were hot pressed and extruded at 100 ˚C using glycerol as
a plasticizer. Pressing without plasticizer produced brittle materials. Tensile properties,
moisture content, water and oil absorption were determined for the hot pressed sheets.
Ball milling of the oil cake did not result in improved properties of the pressed sheets. As the
three plants all have semi-drying oils, a siccative was added in different concentrations to
crosslink the oil and add to the matrix of the bioplastic. Sheets were pressed after preheating
the materials 0h, 2 h or 6 h. Sheets were also pressed from granulated extrudate
with different concentrations of siccative after pre-heating for 0 h or 2 h. Tensile properties,
moisture content, water and oil absorption were determined for the pressed sheets.
Pre-heating before pressing had a larger impact than siccative concentration on the
properties of crambe and carinata sheets. Siccative concentration had larger influences on
the properties of rapeseed cake sheets. Carinata and rapeseed cake were easier to process
than crambe as they flowed better. Carinata sheets and extrudates were more flexible than
crambe and rapeseed cake sheets and extrudates. A tray could be pressed from a mixture of
crambe and rapeseed cake. All three materials show potential to be used as bioplastics for
rigid items, perhaps in packaging applications.
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