Marl, Germany. Specialty chemicals company Evonik has begun work to expand its POLYVEST® HT plant in Marl, Germany. The Coating & Adhesive Resins business line expects the additional production capacity for its hydroxyl-terminated polybutadienes (HTPB) – marketed under the brand name POLYVEST® – to be ready as early as the second quarter of 2024 following the double-digit million-euro investment.

“By expanding our operations, we will continue to provide reliable service to our global customers,” says Dr. Stefan Pfaffenbach, head of the business line. “In a highly competitive market, we are strengthening our position as a cost and innovation leader.”

The expansion comes ten years after the start of production at the HTPB plant in Marl. Dr. Jürgen Herwig, head of the Polybutadienes and Specialty Acrylates product line, says: “Dual-use products such as polybutadienes require a high degree of sensitivity and expertise when dealing with customers and authorities. So when it comes to marketing this highly specialized product, we can rely on our colleagues’ experience and expertise to promote the additional capacities.”

Production is backward-integrated, as butadiene is produced directly at the Marl site and hydrogen peroxide is supplied by the Evonik Group. Thus, Evonik benefits from supply security for the raw materials for its POLYVEST® production. In addition, Evonik’s Application Technology and Research & Development teams are also located at the Marl site, providing a seamless link from laboratory development and testing, through to production.

POLYVEST® HT is a liquid, hydroxyl-terminated polybutadiene produced by free-radical polymerization. The polymer has a highly hydrophobic polybutadiene backbone and primary hydroxyl groups that are accessible for precise chemical modification.

POLYVEST® HT is used as a polyol component in various adhesive and sealant applications. POLYVEST® HT-A is intended for aerospace applications.


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