MacroCycle Technologies Raises $3M Seed VC II Round Led by Clean Energy Ventures to Scale PET Chemical Recycling Technology 

MacroCycle Technologies, a Cambridge-based clean materials startup developing a breakthrough chemical upcycling process for PET and polyester waste, has raised $3 million in a Seed VC II round as it accelerates efforts to commercialize its circular plastics technology and scale pilot production for industrial customers.

The company is building a proprietary platform that transforms end-of-life plastics into virgin-grade PET and polyester resins without breaking polymers down into monomers or fossil fuel derivatives. Its process is based on cyclic macromolecule chemistry, designed to significantly reduce energy consumption and emissions compared to conventional mechanical and chemical recycling methods. MacroCycle’s technology targets one of the largest environmental challenges in the materials sector, where the majority of plastic waste is still landfilled, incinerated, or downcycled.

The latest funding round was led by Clean Energy Ventures, a venture capital firm focused on early-stage climate and energy technologies. The round also included participation from Volta Circle, KdT Ventures, Neotribe Ventures, and Indorama Ventures, a global polyester and PET manufacturing company that has been increasingly active in sustainability-driven materials innovation investments.

The new capital follows MacroCycle’s earlier $6.5 million seed round, which brought together Clean Energy Ventures, Volta Circle, KdT Ventures, Indorama Ventures, and Neotribe Ventures. Across its funding history, the company has now raised approximately $9.6 million, including multiple grants and accelerator support from organizations such as Greentown Labs and Massachusetts Clean Energy Center, reflecting strong backing from both venture and public-sector climate innovation programs.

MacroCycle’s leadership team includes CEO Stwart Peña Feliz and CTO Dr. Jan-Georg Rosenboom, who are focused on scaling the company’s chemistry platform from pilot-scale demonstration to early commercial deployment. The company has already expanded its process from laboratory experimentation to pilot plant operations, supported in part by infrastructure at The Engine in Massachusetts, enabling it to validate performance at a larger production scale.

According to the company, its technology can reduce energy usage by up to 80% compared to traditional fossil-based PET production and may also significantly lower capital expenditure requirements compared to competing recycling approaches. These efficiency gains are central to its commercial strategy, as it aims to produce cost-competitive recycled materials that meet or exceed virgin-grade polymer standards for use in packaging, textiles, and other high-volume applications.

Investors in MacroCycle are backing the company’s potential to address structural inefficiencies in global plastics recycling infrastructure. Clean Energy Ventures, which led the round, has consistently focused on early-stage technologies capable of delivering measurable carbon reductions in industrial systems. Volta Circle and Neotribe Ventures bring additional deep-tech and climate-focused expertise, while Indorama Ventures adds strategic industry alignment given its position as one of the world’s largest PET producers.

The funding will be used to expand pilot plant capacity, advance process optimization, and support initial commercial partnerships with customers interested in adopting low-carbon recycled PET. MacroCycle also plans to grow its engineering and materials science teams as it moves toward larger-scale production trials and early market validation.

As global pressure increases on manufacturers to reduce plastic waste and carbon emissions, MacroCycle is positioning itself as a next-generation materials company aiming to decouple PET production from fossil fuels. With its latest financing, the company is expected to push further toward commercialization, bridging the gap between laboratory innovation and scalable industrial recycling solutions.