3 research outputs found
Polylactic acid as a promising sustainable plastic packaging for edible oils
The influence of renewable packaging materials on the oxidative stability of sunflower oil was investigated to evaluate whether they could be used as alternatives to conventional plastics. Two renewable bottle materials, polylactic acid (PLA) and bio-polyethylene (Green-PE) were compared to conventional plastics consisting of virgin and recycled polyethylene terephthalate (PET, r-PET) and regular polyethylene (PE), in a storage study over a period of 56 days. The results showed that the progress of lipid oxidation in PLA was similar to PET and r-PET until day 28, while it was significantly increased in PE and Green-PE. Benzene was detected as the only migration compound in the oil stored in PET and r-PET, with concentrations of 0.153 ± 0.027 µg/g and 0.187 ± 0.024 µg/g after 56 days of storage. The study concluded that PLA could be used as an alternative packaging material for edible oils to replace PET.This work was kindly funded by the Austrian Science Fund (FWF): P 34512. J. Alberdi-Cedeño thanks the EJ-GV for a postdoctoral grant (POS_2020_1_0040). The authors want to thank Sandra Auernigg-Haselmaier for the technical assistance with the LC-MS and the NMR core facility of the Division of Pharmaceutical Chemistry at the University of Vienna for providing access to the NMR instruments
Low voltage driven dielectric membrane actuators integrated into fast switching electronic circuit boards
In high-tech companies operating worldwide innovation is the key driver for long-term market success. Hence, innovative engineering technologies not only provide technological challenges but also investment risks for decision makers who want to tread new paths in product development. As an important example, the typically required high operating voltage and the need for high voltage power supplies constitute physical, economic and psychological restrictions for the application of dielectric elastomer actuators (DEA). Therefore, based on the view of product integration we aimed to limit the applied voltage below 600 V. To achieve this goal, we developed membrane actuators made of dielectric elastomers, which can be driven by lower voltages provided by low-cost power supplies. In detail, a particular device was developed with specially designed compression fittings clamping the DEA-film which enabling a simple electric contact between the actuator and the circuit board. The prefabricated actuator module was integrated in a fast switching, low-cost electronic circuit board. The power supply generates up to 550 V with a slew rate of a few microseconds, whereas the whole circuit has the geometrical dimension of a credit card. A plunger connected to the DEA-film moves out of plane when the actuator is activated. With the use of permanent magnets, interacting with the plunger, the system can be enhanced to meet industrial requirements in force and stroke. The resulting 'embedded' system offers a platform for further applications in different industrial segments and applications for instance in automation with valves, grippers or micro pumps in process automation and life sciences