Materials PHA 3D
Materials PHA 3D printing filaments Compost heap 3D Printing Hydrogen Flexible CO 2 emissions Cycle of PHAbulous Philaments PHAbulous Philaments Greenhouse gas Rigid Microbe O O Poly(3HB) n+1 Polyhydr yhydroxy- alkanoates (PHA) With the explosive growth of the global 3D printing industry, a new market for plastic materials has opened up. In fact, it is estimated that by 2020, there will be over 115,000 tonnes of plastics used by 3D printers worldwide. However, a considerable proportion will never make it into a product, but will be consigned to the waste heap known as failed prints. The question is, where will all the plastic come from? And more importantly, where will it end up? An Austrian start‐up called Saphium Biotechnology (Kapfenstein, Austria) thinks that it has come up with the answer. The company, formed by a group of friends who met the University of Graz is developing a new type of 3D printer filament, called “PHAbulous Philaments”. According to the Saphium Biotechnology team, PHAbulous Philaments are all‐natural and compostable 3D printing filaments, which, unlike many others on the market, contain no toxic additives and are manufactured with natural colors only. Compostability certification (according to EN 13432) will be applied for soon. As the name suggests, the new filament is made of a bioplastic belonging to the polyhydroxyalkanoate (PHA) family. PHAs are biopolyesters that are produced and stockpiled by microbes as an energy storage material. This material can be harvested from the bacteria producing it and processed into pellets – and now, apparently, also into filament. By adjusting the conditions under which the bacteria are cultivated, it is possible to optimize the PHA produced by the bacteria for the production of 3D printing filament. PHAbulous Philaments stands as one of the first generations of pure PHA filaments on the market. Since PHAs are biological in origin, they can also be completely broken down by microorganisms in the environment. According to the company, their filament will degrade within 60 days when buried in soil, without leaving a trace. “Consumers will no longer have to throw their flawed prints into the bin any more, but we expect that they will be able to dispose of them in their compost pile,” as Christof Winkler‐Hermaden, CSO of Saphium explained to bioplastics MAGAZINE. “The microorganisms in the compost will digest the plastic and the resulting humic substances will fertilize the soil. Yet while the biodegradability of PHA is a major plus point, especially in the light of the fight against plastic waste, just as important is the fact that their production is biological and based on renewable resources. The bacteria, which are grown in large steel fermentation tanks, are fed on hydrogen that is produced by electrolysis using the energy of solar panels and carbon dioxide. “The carbon dioxide is a waste product of industry,” Christof 26 bioplastics MAGAZINE [05/15] Vol. 10
Materials explained. “Big industries have to pay to emit their carbon dioxide emissions into the air, but we can take them cheaply and convert them into bioplastics.” Saphium developed a simple and cost effective way to extract and purify PHA. “We have established a microbe strain that secretes those PHAs into the surrounding culture media, where we can collect it easily,” said Christof Winkler-Hermaden. “Once the PHA leaves the microbes, it is perfectly fit for use.” And because the material degrades back into carbon dioxide, the production process is carbon neutral. The PHA used to make the new filaments has other advantages as well, says Saphium Biotechnology. Water and UV resistant, its mechanical properties are comparable to those of polypropylene. The material offers a lower melting temperature (145 – 150 °C) and, due to a glass transition temperature under 0 °C, flexibility. After launching the first prototypical PHAbulous Philament samples on a test market, the Saphium aims to develop filaments with different properties ranging from flexible to rigid, in order be able to provide materials for every 3D printing application. As CEO Reinmar Eggers recently explained it in an interview with Simon Cocking of Irish Tech News: “Right now the earth’s oceans and ecosystems are being destroyed every single day with all the plastic waste we produce. We can’t turn back time and we can’t abolish plastics since they are an important part of everyday life, but Saphium can make them non-toxic and compostable.” KL/MT www.saphium.eu bioplastics MAGAZINE [05/15] Vol. 10 27
