Quiet helper for clear wind blades - Covestro Desmopan 9370A TPU shines in protection duty

Reviewed: ad hoc news Accessory & Components desk. Edited and checked on 2026-06-17, 19:02. Details in the imprint.

Desmopan 9370A TPU from Covestro is one of those quiet helpers you never see on glossy brochures, but you feel it every time a wind turbine spins smoothly in salty air. The translucent material squeezes into seals, gaskets, and protective parts, taking on the dirt, moisture, and stress instead of the expensive hardware.

What Desmopan 9370A is made for

Covestro positions Desmopan 9370A as a thermoplastic polyurethane for profiles, gaskets, and protective elements where elasticity and abrasion resistance have to coexist. The grade is formulated for high mechanical strength, stable elasticity, and good hydrolysis resistance in long-term outdoor use according to the company’s technical datasheet.

The material belongs to Covestro’s broader Desmopan TPU family, which covers hardness ranges from very soft to rigid formulations and serves industries from automotive to industrial machinery. In wind power, 9370A aims to balance flexible processing on extrusion lines with robust performance once installed in blades or housings.

How it works on a wind turbine

On a modern wind turbine, Desmopan 9370A does its work in the shadows: as sealing lips along service doors, flexible covers over cable entries, or impact-protection strips where rotor blades meet maintenance platforms. It must flex with every vibration and gust while resisting cracking over many seasons.

Technicians on site want a material that feels firm in the hand but still bends without whitening or crumbling when folded sharply. In nacelle seals or tower doors, a snug Desmopan profile reduces rattling, cuts drafts and moisture ingress, and helps keep the interior electronics cleaner for longer intervals.

Processing and design freedom

Because Desmopan 9370A is thermoplastic, profile extruders and injection molders can run it on standard TPU-capable equipment. That means continuous extruded seals, custom overmolded parts, and complex geometries are all possible without switching to thermoset tooling.

Design engineers can shift hardness or color within the Desmopan range if a wind OEM wants brighter safety markings or softer contact surfaces along service ladders. The material’s compatibility with multi-component structures also allows co-extruded profiles that combine a harder body and a softer sealing lip in one piece.

Durability in harsh environments

Offshore wind takes no prisoners: salt spray, UV exposure, and temperature cycles challenge every polymer used on the tower. Covestro’s TPU portfolio is marketed with good resistance to hydrolysis and microbes, seeking to reduce swelling, softening, or surface attack in constant moisture.

In practice, this should mean fewer brittle seals and less flaking after years at sea, provided installation and maintenance are done properly. For operators, every seal that survives one extra inspection cycle without replacement lowers the overall cost of turbine ownership and avoids awkward repair work at 100 meters height.

Sustainability and material choices

All the talk about green power quickly gets uncomfortable when the materials inside the turbines are not sustainable. Covestro publicly pushes approaches such as circular TPU concepts and ISCC PLUS-certified feedstocks in other product lines, signaling a direction for future TPU grades as well.

While Desmopan 9370A itself is a conventional TPU grade, the broader roadmap matters for wind customers planning turbines with lifetimes of 20 years or more. If feedstock sourcing and end-of-life options for TPU seals improve, thousands of small parts in each farm could have a cleaner footprint.

Where it fits in Covestro’s portfolio and stock

Desmopan 9370A is a specialist among many product lines at Covestro, sitting beside polycarbonate sheets, polyurethane systems, and coatings raw materials that all feed into the energy and infrastructure sectors. The grade shows how quietly the group embeds itself deep inside the wind industry’s value chain through components most people never notice.

Shares of Covestro AG (DE0006062144) trade on Xetra in euros.

This article was AI-assisted and editorially reviewed. Product information without guarantee; prices and availability may change at short notice. No investment advice, no buy or sell recommendation. Stock-market transactions involve risks up to total loss.