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MacroCycle Technologies




Cambridge, MA



Jan-Georg Rosenboom

Co-founder & CTO, MacroCycle Technologies

Jan-Georg Rosenboom joins Breakthrough Energy’s Innovator Fellows program from MacroCycle Technologies in Cambridge, Massachusetts. He has more than 10 years of academic and industrial research experience in polymer chemistry and process engineering. As co-founder and chief technology officer, Jan-Georg oversees MacroCycle’s plastic recycling technology and intellectual property development.

MacroCycle Technologies’ patented technology converts plastic waste into virgin-grade quality recycled plastic through a process that requires 80% less energy than competing depolymerization processes and can be powered with renewable energy to be entirely carbon free. Through the Fellows program, MacroCycle will optimize the technology for various waste streams and scale up to provide customers with sufficient material to make the first zero-carbon upcycled PET bottles.

Jan-Georg studied at the Hamburg University of Technology in Germany, University of California, Berkeley, and the University of Cambridge towards a Master of Science in chemical engineering. He completed his Doctor of Philosophy at ETH Zurich and a postdoctoral appointment at the Langer Lab at the Massachusetts Institute of Technology. His passion for blending science with entrepreneurship inspires his work at MacroCycle and has previously led him to co-found a social enterprise and consult for other firms on plastic sustainability.


What’s the best piece of advice you’ve been given?
“Focus on big problems” – Bob Langer. I think this sense of prioritization applies to pressing world issues (e.g., choosing which emission sources to tackle first) but also to daily life when procrastinating with small issues while big decisions are waiting.

Who has had the greatest impact on your career path?
My high school math teacher, Dr. Carmesin, who introduced me to a “Youth Research Germany” project at the age of 16. This experience sparked my curiosity for research and science.

What is your favorite word and why?
“Tatendrang,” which literally translated from German means “action-urge,” describing the excitement to get stuff done. It is a great feeling.

What did you want to be when you grew up?
As a young child I liked Donald Duck comics and especially the Gyro Gearloose character who came up with crafty but not always functional inventions. I said I eventually wanted to become an inventor – which I am now.

Share a fun fact about yourself:
Before I became a scientist-engineer-entrepreneur, my focus was music – loud music, typically performed in front of a darkly-dressed crowd with very long hair…