Innovative PLA Catalyst Solution

SustainCat Team from left to right: Juan Sebastian Romero, Johannes Häufler, Huaiyou Chen.

© SustainCat

The Discourse on Green Chemistry Interactive Pitch Competition, held on November 5, 2024, at Wiley’s Berlin office, showcased innovative projects from early-stage startups addressing environmental challenges. Cohosted by CHEManager and GreenChem, the event saw SustainCat impress the judges with their approach to sustainable chemistry. Their innovative solutions earned them the Jury Prize. As part of their prize, they are featured in this issues CHEManager Innovation Pitch. As the Jury Prize Winner of The Discourse on Green Chemistry Interactive Pitch Competition, SustainCat demonstrated a high-performance catalyst that streamlines Polylactic Acid (PLA) production, cutting costs and energy consumption while improving the crystallinity and molecular weight. This innovation involves melt-phase condensation followed by solid-phase condensation, utilizing acidic supported solid catalysts, specifically calcined zirconium sulfate supported on carriers like SiO₂.

CHEManager: What was the starting point and the motivations of SustainCat?

Johannes Häufler: Our multidisciplinary team was formed in the Treasure Hunting Summer School at the TU Berlin’s Innovation Center. During this program, we discovered the potential of our patent and decided to continue working on it together. We applied to take part in the pitch course and discourse of Berlin Science Week x Wiley x GreenCHEM. As a result, we were able to celebrate our first success with a successful innovation pitch. 

What sets SustainCat apart from existing solutions in the market?

Juan Sebastian: We stand out by enabling direct polycondensation of L-lactic acid through melt-phase and solid-phase condensation, simplifying production and cutting PLA manufacturing time by 3 – 5 times. Unlike conventional catalysts, SustainCat is easily removed via mechanical filtration and can be directly reused, eliminating toxic residuals. It also achieves 60 – 80% crystallinity, which enhances heat resistance, speeds up processing, and makes it ideal for fiber applications and injection molding. In contrast, traditional tin-based catalysts rely on ring-opening polymerization, reach only 40% crystallinity, and leave behind impurities that are difficult to remove.

What are the advantages of the solution SustainCat proposed?

J. Sebastian: The development of catalysts that fasten the polymerization without any undesired side effects is of great interest. We are now able to present oxo-anion modified metal oxides as catalysts that fasten the pre-condensation of lactic acid, especially zirconium sulfate tetrahydrate (ZrS₂O₈) that was calcinated at 450 – 550 °C. A second positive effect is the insolubility of the catalyst within the reaction mass making it easily separable. First experiments produced nearly 100 mol% L-lactic acid units even at high conversion and catalyst concentration. 

Who are your target customers, and what specific problems are you solving for them?  

Huaiyou Chen: Our primary target customers are PLA manufacturers looking to enhance the sustainability and cost-effectiveness of their production processes. We’re helping them stay competitive against conventional plastics and other bioplastics. By making PLA production greener, non-toxic, and recyclable, we help cut costs in this growing market. High performance catalyst manufacturers could also be our customer per patent licensing. And if needed, we’re also open to supplying products directly to PLA end users. 

What’s the vision for SustainCat? Where do you see your team in five years? 

J. Häufler & H. Chen: Our immediate goal is to secure funding to validate our business model. We are focusing on conducting a techno-economic analysis to assess the commercial feasibility of our innovative direct polycondensation process for PLA production. Based on the current granted patent, a subsequent patent is in the plan. This will provide a solid foundation for our next steps. 

In the next five years, we envision two potential pathways: establishing an SME-industry cooperation or founding a startup to commercialize our technology. By demonstrating the efficiency, cost-effectiveness, and sustainability of our approach, we aim to attract industrial partners interested in sustainable plastic and high-performance catalyst solutions. 

Our long-term vision is to make PLA production significantly more sustainable and economically viable, reducing reliance on traditional, energy-intensive methods. With the support of TU Berlin and GreenCHEM, we are positioning SustainCat as a key player for affordable and competitive biodegradable plastics.