Biodegrable, Recyclable Bioplastics from Seaweed-Feeding Microorganisms
Tel Aviv University researchers develop method to make new type of PHAs.
Researchers at Tel Aviv University have developed a new process that can produce ‘truly sustainable’ bioplastics in that they do not require the use of plants or water. Their process produces a PHA (polyhydroxyalkanoate) type of bioplastic from marine microorganisms that completely recycle into organic waste.
PHAs are polyesters produced in nature by a broad number of microorganisms including the through bacterial fermentation of sugars or lipids, on which we have reported on in the past. Over 150 different monomers—all biodegradable, can be combined within this family to produce materials with a broad range of different properties. They can be either thermoplastic or elastomer materials with melting points ranging from 104 F to 356 F.
This multidisciplinary TAU collaboration between Dr. Alexander Golberg, of TAU’s Porter School of Environmental and Earth Sciences and Professor Michael Gozin of TAU’s School of Chemistry, which was recently reported in the journal of Biosource Technology, focused on harnessing microorganisms that feed on seaweed. Said Golberg, “Our raw material was multicellular seaweed, cultivated in the sea…these algae were eaten by single-celled microorganisms, which also grow in very salty water and produce a polymer that can be used to make bioplastic.”
Golberg acknowledges that there are already factories that produce PHAs in commercial quantities but they use plants that require agricultural land and fresh water. “We have proved it is possible to produce bioplastic completely based on marine resources in a process that is friendly to both the environment and its residents.”
The research team is now conducting basic research to find the best bacteria and algae that would be most suitable for producing polymers for bioplastics with different properties.
To properly understand the differences in performance between PET and PBT we need to compare apples to apples—the semi-crystalline forms of each polymer.
This so-called 'commodity' material is actually quite complex, making selecting of the right type a challenge.
The rate of loading for a plastic material is a key component of how we perceive its performance.