13. Jan 2015
Compostable, biodegradable barrier coating for biodegradable film for food packaging
Although bioplastics are fast gaining popularity for use in the packaging industry, food packaging continues to be a challenge. Bioplastic film materials tend not to be odor-resistant and moreover to have poor moisture and oxygen barrier properties, leading to contamination problems and spoilage.
A consortium of researchers who are collaborating within an EU project called DibbioPack, short for Development of Injection and blow extrusion molded BIOdegradable and multifunctional PACKages by nanotechnology (www.dibbiopack.eu) are now working to overcome these challenges One of the members of the consortium working on this project is Fraunhofer ISC. This institute has been developing hybrid polymers called ORMOCER®s for the past 20 years. Now, within the scope of the Dibbiopack project, an ISC team led by Dr. Sabine Amberg-Schwab has developed a biobased type of ORMORCER which is both biodegradable and compostable. The material is suited for applications such as household containers and packaging films, and can be engineered with whatever properties are required by the relevant application.
To achieve the biodegradability of the hybrid ORMOCER®s a concept was developed to integrate biopolymers and to directly bond these to the ORMOCER® precursor. To that end, researchers chemically modified biopolymer such as chitosan and cellulose, to enable these to be bonded to an inorganic scaffold of silicon dioxide – which in itself offers good barrier properties. And, while unlike the rest of the ingredients used this scaffold does not biodegrade, only tiny remnants of silicon dioxide remain behind after degradation.
While the compostability of the bioORMOCER® coated films has already been established in test processes, tests are currently in progress within the scope of the Dibbiopack project to determine whether the process complies with prevailing international standards. The project will run until March 2016. During the next step, the material will be tested at pilot scale: the researchers will apply the bioORMOCER® coating to bioplastic films using a roll-to-roll process, after which these will be subjected to extensive testing, in order to demonstrate their suitability for everyday use. “The new packaging material has to be good enough to match the current state of the art,” said Amberg-Schwab.
The researchers are presenting a prototype of the new bioORMOCER® coated film at the Fachschau nature.tec during the Green Week in Berlin (16 – 23 January). (KL)