MacroCycle Technologies

MacroCycle Technologies, a Cambridge, Massachusetts-based company founded in 2023, is addressing the significant challenge of plastic waste with a novel chemical recycling process. The company was established by CEO Stwart Peña Feliz, a former ExxonMobil process engineer with an MBA from MIT Sloan, and CTO Dr. Jan-Georg Rosenboom, a polymer scientist from MIT's Langer Lab. The collaboration began when the two met in a climate and energy ventures class at MIT. Peña Feliz's expertise in scaling industrial processes complements Rosenboom's deep technical knowledge in polymer chemistry, which formed the basis of the company's technology during his academic work at MIT, ETH Zurich, and Politecnico Di Milano.

The firm operates in the cleantech and circular economy sectors, tackling the environmental problem of PET and polyester textile waste. Its core business is upcycling this waste into virgin-grade mPET (MacroCycle-PET) resin, which can be used as a drop-in solution for new products. The company targets a wide range of clients, including those in the cosmetics, textiles, home goods, food and beverage, and fashion industries. Initially planning to license its technology, MacroCycle pivoted to manufacturing its resin directly in response to market demand for a proven, scalable solution.

MacroCycle's proprietary technology represents a significant departure from traditional recycling. Instead of breaking down plastics into their basic molecular building blocks (monomers), a highly energy-intensive process, it uses a unique solvent-catalyst mixture at moderate temperatures. This process dissolves the polymer and rearranges the linear chains into cyclic oligomers—the 'macrocycles' from which the company takes its name. These intermediates then undergo Ring-Opening Polymerization (ROP) to form new, longer polymer chains, effectively 'upcycling' the material to a quality comparable to virgin plastic. This method can handle a wide array of waste, from low-grade flakes to poly-cotton textiles. The company states its process uses up to 80% less energy than fossil-based PET production and requires 50-75% lower capital expenditure than competing chemical recycling methods.

In February 2025, the company announced a $6.5 million seed funding round led by Clean Energy Ventures and Volta Circle, with participation from KDT Ventures and Neotribe Ventures. This followed earlier support from the Breakthrough Energy Fellows program and pre-seed funding that enabled the technology to scale 100x from the lab to a pilot plant. The capital is being used to expand operations and further scale its pilot facilities to validate the technology at a larger scale and produce the first garments and bottles made entirely from its recycled resin.

Keywords: PET recycling, polyester upcycling, chemical recycling, circular economy, cleantech, sustainable materials, plastic waste solutions, polymer chemistry, virgin-grade PET, low-energy recycling, textile recycling, SolvoGenesis, Ring-Opening Polymerization, Stwart Peña Feliz, Jan-Georg Rosenboom, Breakthrough Energy Fellows, advanced recycling, green technology, sustainable packaging, circular plastics