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Senior Polymer Scientist

Shellworks

Shellworks

London, UK
GBP 50k-60k / year + Equity
Posted on Mar 3, 2026
Materials · Shellworks London

Senior Polymer Scientist

Help us build a world without plastic pollution by championing new product development at Shellworks. Join a fast-moving team making a real environmental impact.

📍 London, N4
🏛️ 4 days in our office, 1 day from home (choose from Tue–Thu)
💰 £50 - 60k per annum + equity

About Shellworks

At Shellworks, we’re on a mission to make plastic waste a thing of the past. We’re creating a new generation of materials - sustainable, high-performing, and designed to disappear. By reimagining how materials are made, we’re tackling one of the world’s most urgent environmental challenges.

Key Responsibilities

  • Lead the end-to-end development of proprietary polymer blends and additive packages. You’ll be responsible for expanding our core material's scope, successfully hitting commercial performance targets.

  • You will engineer formulations that remain robust and uncompromising during a product shelf-life but maintain rapidly biodegradable the moment they reach their end-of-life.

  • Develop a predictive framework that correlates lab-based rheological and thermal data to real-world machine settings. Your goal is to eliminate trial-and-error by predicting how materials will behave before they hit the factory floor.

  • Expand our internal testing suite to connect microstructure analysis (crystallinity, melt stability, etc) to macroscopic failure modes. You’ll deep-dive into analysis to understand exactly why materials succeed or fail in the field.

  • Collaborate daily with our manufacturing and engineering teams. You’ll ensure your formulations are "manufacture-ready" stable, repeatable, and optimised for industrial-scale extrusion and molding.

  • Act as the technical bridge between our design and commercial teams. You will translate customer requirements into concrete chemical specifications, ensuring our materials meet the aesthetic and functional needs of the world's biggest brands.

  • As a member of a dynamic team, you won’t just stay in your lane. You’ll jump in wherever needed from vetting new sustainable feedstock suppliers to identifying and researching new opportunity spaces.

Our Ideal Candidate

  • Holds a Masters / PhD in Polymer Science, Materials Science, or a related field, with at least 2 years of industry experience.

  • Brings a solution focused, results-driven mindset and a strong willingness to learn, this is a hands-on role that requires curiosity and initiative.

  • Deep command of polymer chemistry, with the ability to connect rheology, crystallinity, thermal behaviour, and melt stability to real processing outcomes.

  • Comprehensive knowledge of polymer science, formulation and analysis - you know how to connect the microstructure of polymers to macroscopic enhancements.

  • Independent decision maker, you feel confident operating in ambiguity while driving clarity and momentum.

  • A do it yourself / can do mentality - not focussed on boundaries but interdisciplinary problem

What we offer

🌴 21 days holiday + birthday off + 27–31st December (plus public holidays)
📚 Growth and development opportunities as we scale
👍 Competitive salary + equity options
🎉 Regular socials + daily catered lunch at the office
🐚 A tight-knit, mission-driven team working on something that matters

Join Us

Becoming a part of Shellworks means being part of a team that’s passionate about sustainability and innovation. Our world-class team includes experts in materials science and visionary entrepreneurs dedicated to creating a better future. Together, we’re redefining what’s possible.

Department
Materials
Locations
Shellworks London

About Shellworks

Shellworks aims to address one of the biggest challenges of our generation: plastic pollution. We raised a 6.2Mn Seed round by top-tier investors globally and shipped our first 100,000 units in 2022. We're now scaling our team to help us accelerate towards our mission.

We’re a group of critical optimists from backgrounds like design, engineering, and science. We aren’t bound by existing rules and stereotypes and are fundamental believers that there must be a better way. As an early-stage startup, you’ll play a fundamental role in shaping Shellworks’ future.

Materials · Shellworks London

Senior Polymer Scientist

Help us build a world without plastic pollution by championing new product development at Shellworks. Join a fast-moving team making a real environmental impact.