BASF patents new hot gas welding process for plastics

• Significantly shorter welding times while maintaining high weld seam quality
• Energy-efficient joining that is gentle on materials
• Particularly suitable for Ultramid^® Advanced (polyphthalamide, PPA) applications in eMobility and fuel cell technology

BASF has patented a novel hot gas welding process for plastics. The technology enables thermoplastic components – especially those made of Ultramid^® Advanced (polyphthalamide PPA) – to be welded significantly faster, more energy-efficiently and in a more material-friendly manner than with conventional hot gas welding processes.

At the heart of the patented solution is a special tool design: the hot process gas is no longer blown onto the welding ribs selectively from individual nozzles; instead, it is guided in a targeted manner along the welding ribs via channel-like structures. This ensures even gas distribution and minimizes heat losses. The welding ribs are plasticized more homogeneously without requiring high gas temperatures or very small nozzle distances.

Short welding times and high strengths

“Tests on PPA specimens have shown that the patented process can produce durable welded joints after very short heating times of around ten seconds,” says Stefan Mochev, Team Leader Materials & Parts Testing. “By comparison, with conventional hot gas welding technologies, it is often not possible to achieve any joint at all within these short times. At the same time, high weld seam strengths are achieved, making the technology particularly attractive for function-integrated components with high mechanical requirements.”

Another advantage is the greater melt layer thickness that can be achieved within a short time. This provides additional leeway to compensate for component warpage – an important aspect for large-format or complex components.

More efficiency and process reliability

The patented hot gas welding process allows lower process temperatures and thus reduces the consumption of energy and inert gas. In addition, the distance between the gas nozzles and welding ribs can be designed to be larger, which virtually eliminates the risk of individual nozzles becoming clogged by molten material. This increases process reliability and reduces maintenance effort.

Contribution to sustainable mobility solutions

Due to their high thermal, chemical and hydrolytic resistance, polyphthalamides are key materials for applications in eMobility and fuel cell systems. With the patented hot gas welding process, BASF expands the processing options for this material class and helps customers join components more efficiently and further increase functional integration.
 

About BASF

At BASF, we create chemistry for a sustainable future. Our ambition: We want to be the preferred chemical company to enable our customers’ green transformation. We combine economic success with environmental protection and social responsibility. Around 108,000 employees in the BASF Group contribute to the success of our customers in nearly all sectors and almost every country in the world. Our portfolio comprises, as core businesses, the segments Chemicals, Materials, Industrial Solutions, and Nutrition & Care; our standalone businesses are bundled in the segments Surface Technologies and Agricultural Solutions. BASF generated sales of around €60 billion in 2025. BASF shares are traded on the stock exchange in Frankfurt (BAS) and as American Depositary Receipts (BASFY) in the United States. Further information at www.basf.com. 

About BASF’s Performance Materials division

BASF’s Performance Materials division drives the transformation of the plastics industry by uniting sustainability with high performance. Our materials expertise, deep industry know-how, and broad product portfolio make us the preferred partner for comprehensive solutions across the plastics lifecycle. With dedicated material-focused teams, strong R&D power, and a global production network close to our customers, we deliver tailored offerings that meet regional and industry-specific needs. Our products enhance performance and efficiency in key sectors such as automotive, construction, consumer goods, and industrial applications. Together with our partners, we embark on #OurPlasticsJourney towards a more circular and sustainable future. In 2025, the Performance Materials division achieved global sales of €6.4 billion.  

Join #OurPlasticsJourney on LinkedIn  https://on.basf.com/PM_LinkedIn 
and  in our newsletter  https://on.basf.com/PM_Newsletter.  
Further information at https://www.performance-materials.basf.com. 

P-26-098