Ecoplast from Slovakia

Similar materials are currently used only minimally. The contemporary plastics are made predominately from non-recyclable raw materials and thus they burden the environment excessively. Negative impacts of these plastics can be seen all around us ... For this reason in our society there is the need to produce such a "plastic material" which is recyclable whereby it will serve as an environmentally friendly packaging material.

CHARACTERISTICS OF MATERIAL

A new biodegradable material by Slovak scientists is based on renewable sources of raw materials. The basic polymers are polylactic acid (PLA) and polyhydroxybutyrate (PHB). PLA is synthesized by polymerization lactic acid or from dilactide. Both of these monomers are produced by fermentation of starch. Polyhydroxybutyrate is bacterial polyester produced biotechnologically as a source of nutrients when suitable bacteria consume sugars and synthesize PHB from them. PHB is then isolated. The disadvantage of both polymers is their fragility, therefore a low flexibility of especially thin-walled products and as well, especially in the case of PHB, a very high sensitivity to thermal degradation during their processing.

"The solution, which is the subject of invention application, consists in the preparation of a mixture of the two polymers and some additives or modifiers, also proceed from renewable sources of raw materials. By mixing of two fragile polymers there is produced a tough mixture. In addition this mixture has got an increased resistance to degradation during processing", explains Assoc. prof. Pavel Alexy from Department of Plastic and Rubber at the Institute of Polymer Materials of Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, one of the co-authors of the project.

In addition to these mentioned polymers we can add the starch with plasticizer into the mixture. After this means a multi-component mixture will be created on the base of polymers from renewable sources. This mixture has got a wide variability in processing and physical-mechanical properties depending on the composition and technology of its preparation. Moreover, unlike for example oxo-biodegradable plastics, these materials contain no prodegradants. Because it is related to a polyester base, these materials, if they do not reach the biologically active environment, are sufficiently stable (resistant to external influences) and so are long-term storable without a loss of mechanical properties.

HIGH APPLICATION POTENTIAL

Unlike previously known comparable materials, this news item from Slovakia is characterized much better mechanical properties, predominately high flexibility and toughness. These attributes give the material a high application potential primarily for use in the packaging technology. From now various foils, cups as well as bottles and their caps can be "green". Also prospectively there is a counting with the application of new polymer in some injection molded products, hollow blowing products and the like.

Until now plastics were the domain of oil and its derivatives. Gradually they pushed out primarily metal materials from the market. In addition to the lower weight during this transition from metal to plastic there was decisive a price which is much lower. Can the new material compete in this area as well? Even now the technology for its production and processing as well as raw material base make possible to produce material at prices that are close to those of commodity plastics which are oil-based produced. The society would then gain real compensation so called oil plastics, especially in the packaging technology.

Implementing AN Idea into Practice

It is one thing to develop something new, and the other, perhaps more difficult, is to promote the idea at the market. The first step is to protect your invention with a patent. New biodegradable material is the subject of invention application in Slovakia, but also in the whole world. Even the award at the world competition does not keep waiting long itself. The material got the gold medal at the exhibition of inventions 2012 TAIPEI INTL INVENTION SHOW AND TECHNO­MART in Taiwan.

The second step is to test the suitability of processing for the laboratory developed biodegradable material by the injection moulding technology and material preparation for operational tests in the framework of transfer of the research results into practice.

Based on this need, Slovak Plastics Cluster (SPK) which organises plastic producers together with the research and development institutions (SAS, STU BA), concluded with the Ministry of Education, Science, Research and Sport of the Slovak Republic in 2012 the Grant Aid Agreement for Scientific and Technical Services.

Grant aids are provided for activities supporting the transfer of research and development results for the members of cluster SPK in practice by increasing the involvement of the business community to a cooperation with scientific and research institutions at the transformation of R & D outputs in innovation processes, by creating conditions to increase their application in manufacturing and technological process. The grant aid is intended to promote scientific and technical services in the field of biodegradable plastics and their processing. It is funded from the state budget.

The application of production for this material has not realised yet under laboratory conditions. The material was created that meets parameters of the injection moulding. This phase was characterized by the preparation of a wide range of mixtures from which the formula will be developed by optimization procedure for pilot plant and industrial testing. In pilot plant conditions there was produced 150 kg of material, which presently is tested for injection moulding under industrial conditions. Industrial testing is carried out according to the concluded Contract in the membership plastic organization SPK – in the company Esox – plast, Ltd., Uhorská Ves. By testing there are determined the optimal properties of injection moulding as well as mechanical properties.

Based on the review results there is an expectation of formula modification so that there will be solved one or two variants of the biodegradable material. At the same time probably it will be necessary to modify the rheological or also physical and mechanical properties of the designed mixture. Only then it will proceed to the zero-series production of biodegradable packaging or packaging components for the real application. After successful testing of material utilization in the packaging technology the verification of its use in other areas could follow.

Incoming destiny of this material now depends on the results of the first tests and refundment of project costs. In case of finding the investor, the authors are able to prepare material for mass production within one to two years. •

The project was funded by the grant of the Ministry of Education, Science, Research and Sport of the Slovak Republic.