Planet Smart raises £750k to replace hidden plastics in nappies with a biodegradable polymer
This article covers Planet Smart, a London biomaterials startup, which has closed a £750k pre-seed round to accelerate development of PlanetSorb, a biodegradable superabsorbent polymer. The funding aims to scale R&D and begin commercial trials with hygiene manufacturers to replace fossil-based plastics in nappies and sanitary products, addressing a significant source of plastic pollution.
Planet Smart, a London-based greentech startup, has raised £750k in a pre-seed round to commercialise PlanetSorb, a biodegradable superabsorbent polymer designed to replace fossil-based plastics inside nappies and sanitary products. The funding will support R&D scale-up, commercial trials with hygiene manufacturers and expansion of the team at its White City laboratory.
Why it matters
Disposable hygiene products are a large and largely hidden source of plastic pollution. Industry estimates cited by Planet Smart put the global discard rate at roughly half a million nappies and pads every minute. At the same time regulators in Europe are tightening rules: the EU banned intentionally added microplastics last year and forthcoming measures on sourcing fibres and woodland products are raising the cost of conventional raw materials such as wood pulp.
If PlanetSorb delivers on claims of rapid biodegradability and competitive cost, it could offer manufacturers a way to meet regulatory and sustainability targets without raising product prices.
Inside the product
PlanetSorb is a polymer made from poly amino acids that Planet Smart says biodegrades within six months and does not leave microplastics. The company reports lab-scale performance metrics including absorption of more than one litre per gram — up to twice the absorbency of traditional materials — and industry-standard retention rates. Third-party tests have reportedly confirmed the material is non-toxic and dermatologist approved.
Because the material is higher-performing by weight, manufacturers can use less material to achieve the same performance, enabling thinner, more comfortable products without a significant cost increase. Planet Smart also sees applications beyond hygiene — agriculture, wound care, food packaging and industrial uses such as mining waste management — in any sector that relies on materials to absorb or retain liquid.
The company says it has three letters of intent from leading hygiene manufacturers and two purchase orders from European brands, and plans to begin commercial trials with global hygiene manufacturers from its White City lab.
Who are the investors?
Planet Smart raised £750k in a pre-seed round led by General Inception and Vertical Venture Partners, with additional backing from Innovate UK and the Undaunted Accelerator. The funds will be directed to scaling R&D, hiring technical staff and initiating pilot trials with manufacturers ahead of larger manufacturing investments.
In the announcement, Sara Jones, Investor at General Inception, said:
Planet Smart exemplifies the kind of high impact, science driven company that can move the needle on climate and waste. They’re tackling a global pollution issue with genuine commercial pragmatism.
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Founder perspective
The company was founded by Gerald Marin and Maurice Rüttimann. Marin, a materials scientist originally from the Philippines, met Rüttimann while they were lockdown flatmates in Brussels. The idea traced back to Marin volunteering on a river clean-up and observing the scale of waste from disposable nappies. The pair initially ran an NGO focused on plastic waste before shifting to material science.
Planet Smart has assembled a team that includes polymer chemists and industry veterans from BASF and P&G Ventures, and operates from a laboratory in London’s White City innovation hub. With this round the team plans to scale technical development and commence commercial pilots, targeting one kilotonne of production capacity — equivalent to about 45 million nappies’ worth of PlanetSorb — by the end of 2028. The company expects to raise a subsequent funding round in 2026 to expand manufacturing and pursue licensing partnerships.
In the announcement, Gerald Marin, Co-founder & CEO at Planet Smart, said:
We’ve shown that sustainability doesn’t have to mean sacrifice. Our material is greener, faster, and built to scale, and crucially, it simply disappears when its job is done. Everyone was talking about plastic bottles and plastic bags, but hygiene products are one of the biggest sources of microplastic pollution and people don’t even realise it. Our polymer could change how entire sectors think about absorption.
In the announcement, Maurice Rüttimann, Co-founder & COO at Planet Smart, said:
This is a breakthrough for both performance and the planet. If we can replace the hidden plastics in everyday products without increasing cost, there’s no excuse not to change.
The bigger picture
Materials that remove microplastics and biodegrade without compromising performance are a clear commercial priority for the hygiene sector as regulation bites and procurement teams push for lower-carbon supply chains. Planet Smart’s approach — replacing the SAP layer inside products rather than re-engineering whole product categories — is a pragmatic route that could be attractive to large manufacturers seeking incremental but verifiable sustainability gains.
The deal also reflects growing interest from greentech investors in early-stage materials innovation that can be industrialised at scale.
Planet Smart’s combination of grant support from Innovate UK, accelerator backing and private investment is a common pathway for UK greentech ventures attempting to move from lab to pilot production. If its pilots and supply agreements convert into scale, the company will join a small but growing cohort of European firms commercialising biodegradable alternatives to commonly used plastics.
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