ARBOCEL® and FILTACEL®
Influence of ARBOCEL® and FILTRACEL® Fibers on PLA Biodegradability
Nearly a
year ago, we at JRS were wondering how our wood and cellulose fibers exactly
influence the biodegradability. We wanted to create facts and not only rely on external
information.
Therefore, we contacted the Fraunhofer IVV and UMSICHT to discuss a suitable test-setup to conduct biodegradability tests with certain PLA compounds.
Because of the broad availability and disputed biodegradability, we decided to use a common PLA. From the JRS product portfolio, we settled to use the cellulose ARBOCEL® B-600 and the CTMP FILTRACEL® EFC-950. To learn, why we decided to use EFC-950 you can read our blog entry about upcoming EU regulations for food contact compounds JRS - Supporting Packaging – EFC Fibers for Food Contact.
Of course, we also carried out mechanical measurements. You can read about them and more in our last blog article JRS - Plant-based fibers in plastics.
Now, back to the biodegradability tests. We conducted two setups under standardized industrial composting conditions. The first test was a downscaled test on disintegration of injection-molded parts, in our case specimens from the mechanical testing. The second, arguably more valuable, tests were aerobic biodegradability measurements based on DIN ISO 14855-1. In these experiments, the generation of CO2 during the aerobic degradation is detected. Subsequently, it is compared with the respective theoretically possible CO2 generation.
In the following graph, you can see the CO2 generation as a percentage of the theoretical CO2 potential.
Aerobic Biodegradation
As you can see, the neat PLA showed a biodegradability according to DIN ISO 14855-1 of around 60%. A compound with 30% cellulose fiber ARBOCEL® B-600 did significantly increase the biodegradability of the overall compound, which can be a way to fulfill biodegradation certificate criteria. The lignin in the CTMP FLITRACEL® EFC-950 seems to hinder the biodegradation of the CTMP fiber within the observed 90 days. However, another interesting result is that the cellulose and CTMP fillers actually do delay the biodegrading process, while still reaching or even exceeding the neat PLA biodegradation after 90 days. This effect is also visible in the disintegration trials, shown in the following pictures. These could be interesting results for application areas, where the physical integrity of the biodegradable part should be stable as long as possible. We would be happy to discuss this with you.
If you are interested in further details regarding these trials or want to discuss the results, please feel free to contact us.
Disintegration
