R&D Chemist, fiber functionalization

About us At Renasens we're building for people who are energized by winning, enjoy ownership, and thrive in a fast-moving environment. Our pace demands individuals who hold themselves to a high standard and care deeply about execution. If you prefer extensive structure, highly predictable environments, or a slower pace of decision-making, we may not be the right fit. In a small team, there's nowhere to hide, in both directions. Great work gets noticed, and so do opportunities to improve. The upside is that your impact is visible, your contributions matter, and strong performance is recognized quickly. Before applying, take a moment to consider whether this environment aligns with how you do your best work.

Your mission at Renasens You see a fiber and instinctively think about what functional groups are sitting on its surface; and what you could do with them. You will bring a methodical mindset and a strong synthetic toolkit to design and execute functionalization chemistry that gives our recycled fibers new performance characteristics. You move between molecular design and hands-on lab work fluently, and you turn ideas into reproducible protocols that survive contact with the pilot. Take end to end ownership of the fiber functionalization workstream (cotton and polycotton) Design and execute grafting, crosslinking, and surface modification chemistry to meet specific performance targets Develop and optimize reaction protocols from lab bench toward pilot-relevant conditions Characterize functionalized fibers using relevant techniquesWrite clean SOPs and contribute to IP generation through structured experimental records Contribute to an organized and clean lab environment

What you bring MSc or PhD in organic chemistry, polymer chemistry, or related field Strong fundamentals in functional group chemistry, reactivity, and reaction mechanisms Experience with grafting, crosslinking, or surface functionalization of polymers or natural fibers Minimum 2 years of industrial R&D experience (chemical, materials, polymer, or textile industry), academic only profiles will not be considered for this role Hands on synthetic lab experience; comfortable designing reactions and troubleshooting when they fail Solid analytical/characterization skills

Who you are Energized by problems; yours, your colleagues' and the ones nobody asked you to solve yet. You don't walk past a challenge, you walk toward it Reliable & Independent: you take ownership of your chemistry and deliver on time without close supervisionTeam over ego; you care more about collective wins than being right Thrive in fast paced environments; You are energized by ambitious timelines and meaningful challenges Translate depth into action, you go deep on reaction mechanisms when needed, but don't get stuck there. You know when to stop optimizing the synthesis and start scaling it.

Great to have but not required Exposure to organic chemistry applied to subcritical or supercritical fluid systems Previous experience in textile, fiber, or cellulose chemistry Experience working at the interface of organic chemistry and process scale-up Track record of contribution to patents or IP

How we work at Renasens Onsite & hands-on: our pilot plant is in Borås, with our headquarters in Stockholm. This role is based where the work happens; close to the lab and the pilot. Expect to spend most of your time on site running reactions and iterating with the team. Small team, high ownership: we are around 10 people. You will own your workstream end-to-end and work directly with the R&D lead, process engineers & CEO. No layers, no committees. Pace matters: We have pilot reception milestones in 2026 and customer commitments behind them. We move fast, decide with the data we have, and iterate.

Compensation & benefits Wellness allowance Pension scheme 30 days vacation Rapid career growth

Employment type Full-time

Location Borås, Viared