Continuous, highly precise production of PLA using alternative energies and metal free catalyst fotorreactive extrusion10 September 2015
Continuous, highly precise production of PLA using alternative energies and metal free catalyst fotorreactive extrusion
The European project INNOREX seeks to develop a new technology of PLA production that will improve its homogeneity and exclude the use of metallic catalysts.
Growing demand for more sustainable solutions is reflected in growing production capacities of bioplastics. According to the current state of the art, metal-containing catalysts are needed to improve the polymerisation rate of lactones, posing a hazard to health and the environment.
The Plastics Technology Center, AIMPLAS, along with eleven other enterprises and technological European centers, has launched the InnoREX project, financed by the 7th Framework Program funds and coordinated by the German Fraunhofer Institute for Chemical Technology - ICT.
This ambitious project seeks to develop a new technology of PLA production (polylactic acid) that will improve its homogeneity and exclude the use of metallic catalysts that were necessary until now. Furthermore, it is expected to obtain energy savings and a single monolayer packaging that may be processed by both polymer processing, the extrusion and injection technology.
To ensure short market entry times commercially well-established co-rotating twin screw extruders will be used as reaction vessels. The reason commercial polymerisations are not yet carried out in twin screw extruders is the short residence time and the static energy input of the extruder, which allows no dynamic control of the reaction. Again, these obstacles will be overcome in InnoREX. The project will use the rapid response time of microwaves, ultrasound and laser light to achieve a precisely-controlled and efficient continuous polymerisation of high molecular weight PLA in a twin screw extruder. Additionally, significant energy savings will be achieved by combining polymerisation, compounding and shaping in one production step.
Parallel to all this, the project includes a detailed analysis of the packaging life cycle. The prototype obtained as a result will be a single thin walled monolayer packaging (of a thickness possibly not exceeding a millimeter) intended for the food sector, processed through injection or extrusion to obtain a thermoforming and film packaging to be used when there are demands of lower thickness.
AIMPLAS role within the project is mainly related to the study of processability (injection and extrusion) of developed PLA grades. Mechanical, physical and thermal characterisation of prepared packages by injection moulding, and extrusion cast-sheet and thermoforming. It will also include an extensive development of additivation strategies.
The project, which started in December 2012, will run until May 2016. In addition, AIMPLAS will organize on October 20th a workshop at their premises, addressed to suppliers of raw materials, end users, researcher centres and universities and it will be focused on the project main objectives and its developments.