German companies jointly develop to make PLA "hard when it should be hard, and degrade quickly when it should be degraded"
In order to expand the application of bioplastics in the field of durable goods, it is necessary to develop strategies that are conducive to the biodegradation of bioplastics at the end of the product life, especially when the size and thickness of bioplastics increase, while not affecting their mechanical properties during the service life.
Recently, in Germany, the SKZ Research Center, together with the Aachen University of Technology and Peiler&Klein Kunststofftechnik, conducted a study focusing on this topic.
The goal of this study is to accelerate the natural degradation of polylactic acid (PLA) by incorporating specific enzymes such as proteinase K and cutinase ICCG into the finished product and using zeolites that "fix" these enzymes by peptide adhesion promoters.
However, how can we avoid the biodegradation of materials during the service life of artificial products?
The researchers explained that the enzyme-loaded zeolites will be converted into PLA zeolite masterbatch through a specially developed extrusion process.
The enzymes are introduced into the PLA matrix in an inert form and are only activated after changes in the environment and after the material has worn or melted; at this point, they can accelerate the degradation process of PLA.
"Through the targeted and modular activation of the enzymes, we hope to offer the industry a solution that will allow the production of plastic products that are mechanically stable during use and that degrade more quickly and efficiently in the environment after the product's function has ended," says Alexander Rusam, researcher and project manager at SKZ.
The results of the initial tests are promising. With the help of a microextruder, samples can be prepared in PLA and finely divided zeolites. The analysis results show that the porous material zeolites are evenly distributed in the polymer matrix. In addition, the researchers found that the addition of enzymes does not adversely affect the mechanical properties of PLA, which is a key goal for the industrialization of this product.
"These initial results prove the feasibility of the process and open up attractive prospects for the development of functional and sustainable plastics," concludes Rusam.
