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Materials World: The VC Firms Betting on Composites for Circularity

As its name suggests, the JEC Investor Day that Sesamers is co-organizing only lasts one day, during JEC World, a must-attend event for all things composites. But several firms in attendance are worth keeping tabs on all year round.

That’s particularly true if you are a founder whose startup helps advance circularity through new materials. The good news is that there is funding out there for you. But as usual with fundraising, it is worth knowing the nuance: Some firms invest pre-idea, while others only look at growth-stage companies.

Taking a step back, it is also useful to know what is driving investors into this space, for instance a climate-oriented thesis, and what other companies they may have already backed.

Without further ado, here are some investors that should be on your radar, and additional details about each of them:

4elements

4elements describes itself as a “venture studio for a sustainable future.” As its venture director Vanessa Amaral explained, its focus is on “pre-seed investments in impact-driven startups that develop breakthrough technologies in materials science, particularly those enabling decarbonization, circularity, and resource efficiency.”

Whether it co-founds new businesses from scratch or joins pre-seed startup founders who already had an idea, it can finance ventures internally up to €6 million. But there’s more than capital, Amaral said:

“Our approach includes helping founders refine their technology roadmap and scale from lab-scale to pilot and industrial production; connecting startups with industrial partners, early customers, and supply chain stakeholders; helping assemble high-performing teams, recruiting key talent, and setting up governance structures; and supporting startups in securing follow-on funding from institutional investors, grants, and corporate partners.”

Infinity Recycling

Infinity Recycling established the Circular Plastics Fund, an Article 9 ‘dark green’ impact fund under the EU’s Sustainable Finance Disclosure Regulation — as such, its ultimate goal is a combo of “great impact and financial returns.”

Infinity Recycling is based in Rotterdam, but its portfolio is international — and growing. It already invested in seven companies, but there’s more to come. By the end of its cycle, the fund aims to have invested in 10-14 companies working with waste valorization technologies that convert end-of-life plastic waste into virgin-grade commodities.

Mandalore Partners

Mandalore Partners is a Corporate Venture Capital as-a-Service firm that specializes in four domains: Insurtech, InvestTech, ImpactTech and IndustryTech. Under its IndustryTech vertical, it has a mandate of driving France’s industrial transformation. 

New materials are central to this mission, founder & managing partner Minh Tran told Sesamers. In particular, the fund is interested in how composites can drive sustainable production, reduce reliance on foreign technologies, and support innovations in key areas like 3D printing, energy storage, and advanced manufacturing.

NOVA 

Created in 2006, NOVA is the corporate venture arm of Saint-Gobain. It invests from Seed to Series A in startups in construction tech, mobility, industrial decarbonation and material sciences.

It also has deep pockets: According to its website, Nova’s total investment in startups corresponds to almost 100 million US dollars. But like other firms on this list, it provides more than capital, and works with Saint-Gobain’s teams to set up strategic co-development partnerships, distribution, marketing or licensing agreements with startups.

Past investments in new materials have included companies like FibreCoat, a German startup developing new fiber-based products for the mobility and construction sectors.

Slate Venture Capital

Slate Venture Capital is a B2B climate tech fund, and materials are core to its investment thesis. “We are actively looking at companies creating advanced materials, bio-based materials, or material using carbon. We are also very interested in recycled materials,” founding partner Sébastien Léger said.

Compared to other firms, one difference is that two of Slate Venture Capital’s founders are ex-entrepreneurs who sold their companies — Eventbrite and PeopleDoc. “Helping portfolio companies is of paramount importance to us. We do so across multiple topics, from overall strategy, growth acceleration to capex execution,” Léger said.

Portfolio companies related to new materials include Arda and Fairmat.

Starquest

Founded in 2008, Starquest supports startups that have the potential to drive significant reduction in greenhouse gas emissions, whether that’s in energy, transportation, agriculture, industrial processes — or new materials. It takes a particular interest in supporting initiatives including circular economy practices, waste recycling, product life extension, and recycling.

In 2022, the Paris-based firm joined forces with Montefiore, a private equity firm dedicated to service SMEs and mid-market companies. Starquest, however, remains focused on high-impact investing, with checks typically ranging from €1 million to €10 million, often for minority stakes.

Syensqo Ventures

Syensqo Ventures is the corporate venture capital (CVC) arm of Syensqo, which emerged after Belgian chemicals group Solvay was split into two entities. Syensqo focuses on clean mobility, electric vehicle batteries, green hydrogen and thermoplastic composites, which also inspires the thesis of its CVC.

“Our investment thesis in composites is centered on addressing the growing needs of our customers for composite parts,” said Syensqo Ventures’ managing partner, Matt Jones. These needs evolve around the objectives of “creating lighter, more manufacturable, cost-effective parts.”

Portfolio startups in this sector include iCOMAT and Plyable. “Both bring innovation to speed up and lower the cost of manufacturing composite parts, in line with our thesis on meeting customer needs in this space,” Jones said.

We hope these investors will find valuable dealflow opportunities at JEC Investor Day 2025, and that some of the exciting composites startups in attendance will soon join their portfolios!

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