From the Sector

• ITA Master's graduate wins Hanns Voith Foundation Award 2023

In his Master's thesis, Flávio André Marter Diniz, a graduate of the Institut für Textiltechnik of RWTH Aachen University (ITA), developed ultra-thin polyethylene (PE) carbon fibres with a filament diameter 2-3 times smaller than usual. In addition, the use of PE-based precursors will make it possible to reduce the price of carbon fibres by 50 per cent in the future, thus opening up a wide range of other possible applications in key industries such as wind power, aerospace and automotive. For this groundbreaking development, Marter Diniz was awarded the Hanns Voith Prize with the Hanns Voith Foundation Award in the category "New Materials". The prize is endowed with € 5,000 in prize money.

Flávio André Marter Diniz won the prize in the category "New Materials" for his master thesis entitled "Investigation of the stabilisation and carbonisation process for the production of ultra-thin polyethylene-based carbon fibres".

The use of carbon fibres in highly stressed lightweight construction solutions, such as today's growth applications of wind turbines or pressure tanks, has become indispensable due to their excellent mechanical properties and low density. High manufacturing costs of conventional PAN precursor-based carbon fibres make the material very cost-intensive. In addition, it is not sufficiently available. New manufacturing approaches that develop alternative raw materials and manufacturing processes can be a key and growth engine for further industrial composites applications.

The aim of the work was to develop a new and cost-effective manufacturing process for high-quality ultra-thin carbon fibres using a polyethylene precursor. For this purpose, the sulphonisation process, which is time-consuming today, was to be significantly shortened. As a result, Mr. Marter Diniz produced novel ultra-thin polyethylenebased carbon fibres with a filament diameter < 3 μm with an excellent surface quality of the fibres without detectable structural defects. The fibre diameter is 2-3 times smaller than that of conventional PANbased CF. This provides the basis for mechanically high-quality material properties. At the same time, Mr. Marter Diniz was able to reduce the sulphonisation time by 25 percent. The developed material and technology set important milestones on the way to cheaper carbon fibres. With PE-based precursors, the price of CF can be reduced by 50 percent compared to conventional PAN-based CF.  

A total of five other young scientists were awarded in six categories (Drive Technology, Innovation & Technology/Artificial Intelligence, New Materials, Paper, Hydropower and Economic Sciences. This year, for the 10th time, the Hanns Voith Foundation awarded the Hanns Voith Prize to outstanding young scientists.

The acquisition of the automotive business of Borgers, announced in January 2023, has been completed with effect from April 1, 2023, following receipt of all antitrust approvals. As a result, Autoneum now operates 67 production facilities worldwide and employs around 16 100 people in 24 countries. With the acquisition of the long-established German company, Autoneum is further expanding its global market leadership in sustainable acoustic and thermal management of vehicles. For the planned capital increase of around CHF 100 million for the long-term financing of the acquisition, the shareholders approved the creation of a capital band.

The purchase agreement signed on January 6, 2023, to acquire the assets of the insolvent Borgers companies by Autoneum could be completed. As a result, Autoneum will take over the assets of the Borgers companies in Germany and the shares in the subsidiaries in France, Poland, Sweden, Spain, the Czech Republic, the United Kingdom and the USA as well as in the company in Shanghai, China, with effect from April 1, 2023. As already communicated, the enterprise value paid amounts to EUR 117 million.

The product and customer range of Borgers Automotive, the specialist for textile acoustics protection, insulation and trim for vehicles, ideally complements Autoneum’s sustainable product portfolio. Particularly with the wheel arch liner and trunk lining product lines as well as the truck business, Autoneum’s global presence offers further potential for profitable growth also outside Europe. In addition, Borgers has more than 150 years of experience in recycling textile materials. In the 2022 financial year, the Borgers Group – excluding the mechanical engineering division which was already sold in the summer of 2022 – generated expected annual revenue of around EUR 700 million and employed around 4 500 employees worldwide. Autoneum has agreed new pricing and delivery terms with Borgers’ customers, which will ensure both sustainable profitability and the further development of technologies and processes.

From April 1, the former Borgers sites in Germany will be part of Autoneum Germany GmbH, which has been in existence for many years. The other subsidiaries worldwide will gradually be renamed Autoneum.

Freudenberg Performance Materials (Freudenberg) will present surfacing veils and core materials for lightweight fiber reinforced plastic (FRP) parts at JEC in Paris, France. Freudenberg will also be showcasing Enka® Solutions flow media and spacers for efficient vacuum infusion, resin transfer and foam injection molding processes for applications in the composites industry, etc. at the international composites show.
 
Freudenberg’s solutions for the FRP industry include a variety of glass, PAN and PET nonwovens, as well as core materials for the production of lightweight fiber reinforced plastic parts. These products are designed for anti-corrosion coatings in piping and tank construction, smooth UV resistant surfaces for facade panels, and other applications for a diverse range of end products. Products made from fiber reinforced plastics must be equipped with surfacing veils to provide abrasion resistance, corrosion resistance, smooth surfaces and mechanical strength. Freudenberg offers high-tech nonwovens that can meet these challenges.
 
Enka® Solutions products are characterized by their typical 3D entangled polymeric filament structures. Thanks to this structure, they are exceptionally suitable as flow media and spacers when producing composite materials.

Many people across the world are bedridden – be it due to illness, an accident or old age. Because those affected often cannot move or turn over by themselves, they often end up with very painful bedsores. In the future, it should be possible to avoid bedsores with the help of materials that can be programmed to entirely adapt their form and mechanical properties. For example, the body support of mattresses made from programmable materials can be adjusted in any given area at the push of a button. Furthermore, the support layer is formed in such a way that strong pressure on one point can be distributed across a wider area. Areas of the bed where pressure is placed are automatically made softer and more elastic. Caregivers can also adjust the ergonomic lying position to best fit their patient.

Materials and microstructuring
Materials for applications requiring specific changes to stiffness or shape are being developed by researchers from Fraunhofer CPM, which is formed of six core institutes with the aim of designing and producing programmable materials. So, how can we program materials? “Essentially, there are two key areas where adjustments can be made: the base material – thermoplastic polymers in the case of mattresses and metallic alloys for other applications, including shape memory alloys – and, more specifically, the microstructure,” explains Dr. Heiko Andrä, spokesperson on the topic at the Fraunhofer Institute for Industrial Mathematics ITWM, one of the Fraunhofer CPM core institutes. “The microstructure of these metamaterials is made up of unit cells that consist of structural elements such as small beams and thin shells.” While the size of each unit cell and its structural elements in conventional cellular materials, like foams, vary randomly, the cells in the programmable materials are also variable – but can be precisely defined, i.e., programmed. This programming can be made, for example, in such a way that pressure on a particular position will result in specific changes at other regions of the mattress, i.e., increase the size of the contact surface and provide optimal support to certain areas of the body.

Materials can also react to temperature or humidity
The change in shape that the material should exhibit and the stimuli to which it reacts - mechanical stress, heat, moisture or even an electric or magnetic field - can be determined by the choice of material and its microstructure.

The journey to application
A single piece of material can take the place of entire systems of sensors, regulators and actuators. The goal of Fraunhofer CPM is to reduce the complexity of systems by integrating their functionalities into the material and reducing material diversity. We always have industrial products in mind when developing the programmable materials. As such, we take mass production processes and material fatigue into account, among other things,” says Franziska Wenz, deputy spokesperson on the topic at the Fraunhofer Institute for Mechanics of Materials IWM, another core institute of Fraunhofer CPM. The initial pilot projects with industry partners are also already underway. The research team expects that initially, programmable materials will act as replacements for components in existing systems or be used in special applications such as medical mattresses, comfortable chairs, variable damping shoe soles and protective clothing. “Gradually, the proportion of programmable materials used will increase,” says Andrä. Ultimately, they can be used everywhere – from medicine and sporting goods to soft robotics and even space research.

• ESD protection in harsh environments:
• Polymer-coated chemical-resistant fabrics and fireproof special textiles with expanded electrostatic discharge (ESD) safety function have been developed.
• Graphene nanotubes used as an electrostatic dissipative material make it possible to add ESD protection without compromising resistance to aggressive environments.
• Efficient working loadings starting from 0.06% are sufficient for stable anti-static properties fully compliant with safety standards and position graphene nanotubes far ahead of other conductive materials.

Protective clothing, upholstery, and industrial fabrics that experience harsh conditions require advanced performance. Depending on the final application, specialty textiles can be augmented with flame retardancy, durability, chemical protection, and other properties. Additionally, ESD protection is obligatory in the chemical, rescue, mining, oil & gas, automotive manufacturing, and many other industries that are subject to safety regulations.
 
In applications where multifunctionality of textile is required, graphene nanotubes overcome the limitations of other conductive materials such as unstable anti-static properties; degradation of strength, or chemical or fire resistance; complicated manufacturing processes; dusty production; carbon contamination on the material’s surface; or limited color options. Recent developments show that graphene nanotubes provide ESD protection to textiles in full compliance with safety standards and without degrading the textile’s resistance to harsh environments, greatly enhancing the value of textiles.
 
One such example is textiles coated with fluoroelastomer (a polymer that is highly resistant to chemicals) augmented with graphene nanotubes from OCSiAl. Nanotubes provide the material with surface resistivity of 10^6–10^8 Ω/sq compliant with EN, ISO, and ATEX standards for personal protective equipment. This new technology opens the door for the fabric to be used in high-level protective suits, combining exceptional protection from chemicals with electrostatic discharge protection.
 
Another example is how graphene nanotube technology is being acknowledged as a replacement for metal yarns in fireproof and anti-static textiles, protecting against sparks, splashes of molten metal, high temperatures, and the risk of sudden electrostatic discharge. While metal yarns require a specific knitting process and storage conditions, incorporating nanotubes in a fabric does not require any changes in the manufacturing process as the water-based dispersion is introduced into the fabric at the fluoro-organic treatment stage. The fabric with OCSiAl’s graphene nanotubes has been proven to maintain the pre-set level of ESD protection (surface resistance of 10^7 Ω) after numerous washes.
 
Permanent and stable electrical conductivity, facilitated by graphene nanotubes, is not only a matter of safety but brings additional value in augmenting dust-repellent properties and touchscreen compatibility for comfort and time savings. At the same time, the ultralow nanotube concentrations result in maintained manufacturing processes and mechanical properties, and improve product aesthetics by making it possible to use a wide range of colors. Altogether, these benefits allow textile manufacturers to create next-generation special textiles with expanded functionality.

The identification of profitable new niche markets has been central to the success and continuous expansion of Germany’s Dolinschek, a leading knitting, dyeing and finishing specialist, located in Burladingen in Baden-Württemberg.

“There is so much more to textiles than just clothing,” says Theo Dolinschek, who runs the company with his brother Erwin. “We handle many different technical materials such as automotive components, geotextiles and wallcoverings, but also those for more unusual applications such as inlays for extractor hoods, cut protection fabrics and even wool felts which are employed as insulation on wind turbines.

“We have also recently started to produce compression stockings in a variety of colours, because not everyone wants them black, beige or skin coloured. The most important product areas for us now are in sportswear, corsetry and lingerie, as well as orthopedic and medical products, workwear and protective clothing, but in addition, many other technical applications.”

The Dolinschek brothers moved their business to the historic site of the former Ambrosius Heim textile company in Burladingen in 2001 in order to expand. At the time, the company – founded by their father in 1980 as a textile wholesaler before moving into dyeing – employed just 13 people. Within a year, the company had bought additional space at the site.

Now, with Theo in charge of technology and sales, and Erwin responsible for production, the company employs almost 100 people and operates on an integrated site of 35,000 square metres.

In 2005, a laminating department was established by the company and since 2012 investment in knitting machines has been ongoing.

“The further we went into vertical integration, the more of our own products we were able to position on the market and so we were also able to make ourselves more independent,” says Theo. “We have continued to develop and today we can produce high-quality fabrics for many fields, with 42 knitting machines, 36 dyeing machines, three stenter frames and many other production and processing machines.”

Dolinschek has also developed its own proprietary TMG dyeing machines which have subsequently been successfully sold to many other companies all over the world. There are currently 11 of these machines  in operation at the Burladingen site and around 45 installed at other companies.

For finishing technology, however, the company relies on Monforts, and has installed a new seven chamber Montex TwinAir stenter range with a Montex®Coat coating unit in knife execution, enabling the coating of dimensionally stable knitted fabrics with polyurethane or acrylate. Another unique feature is the Teflon-coated (non-stick) transportation belt through the system.

The Montex line is also equipped with integrated heat recovery and exhaust gas purification to ensure the most resource-efficient processing available on the market. The exhaust air goes from the Monforts heat recovery system into an existing air/water heat recovery system and then into an electrostatic precipitator.

Highly-intuitive Monforts Qualitex visualisation software allows all machine functions and process parameters to be assessed and controlled easily.

HEATHCOAT FABRICS partnered again with BRÜCKNER Textile Technologies and their sales partner ADVANCED DYEING SOLUTIONS to install a finishing line for industrial textiles. HEATHCOAT FABRICS specializes in the production of technical textiles in the fields of texturising, weaving and warp knitting as well as dyeing and finishing. The prroducts are manufactured for use in the automotive, healthcare, defence, and aerospace industries

Mrs. Regina Brückner, CEO and owner of the BRÜCKNER Group stated: "To meet the complex re-quirements of HEATHCOAT is not easy because of the great variety of technical textiles produced. Our line has to finish light as well as heavy articles, so the design, control and the whole line layout have to be flexible, functional and still easy to operate. Fortunately, the team at HEATHCOAT FABRICS is very innovative and open-minded, and together we worked hard to develop the right technology and han-dling. We are very happy that we could convince this customer, whom we appreciate very much, with the productivity of our line and of course with our technological know-how."

The direct gas heated BRÜCKNER POWER-FRAME stenter with its staggered heating source arrangement every half zone provides best available temperature consistency across the length and the width of the stenter. The unit is equipped with a low-lub, horizontally returning combined pin / clip chain and several fabric paths, especially designed for the different fabrics being processed. Together with HEATHCOAT FABRICS technologists, the BRÜCKNER design team developed a special delivery end of the stenter with different edge trimming and slitting possibilities. Depending on the kind of products, the fabrics can be batched on large diameter A-frames, wound on cardboard tubes or plaited into trolleys.

Geosynthetics have become an indispensable part of the construction industry. PP nonwovens, for example - mechanically bonded continuous fibres made from specially UV-stabilised polypropylenes - are often used in blanket form as barriers, screens and filters, and their strength extends the service life of construction projects. Whether for road construction, or as barrier on glaciers or against weeds - there are myriad applications.

TenCate Geosynthetics uses the PURE LOOP ISEC evo technology to recycle this type of PP nonwoven. The European company, with locations in Austria, France and the Netherlands, is specialised in the development and production of geotextiles for modern civil engineering applications. The edge trimmings and production rejects generated during manufacturing used to be recycled at the Linz site, but not fed back into the company's own production process.

"The demands on us were high," recalls Patrick Wiesinger, project manager at PURE LOOP. "The PP nonwoven is highly tear resistant, which means its a very challenging recycling process. Our ISEC evo machine conserves the quality of the production waste really well during recycling, so we were able to achieve the specified increase in quality for the recyclates."

Another advantage of PURE LOOP technology is the wide range of shapes in which the production scrap can be delivered for processing. "Our ifeed technology with double feed ram system and singleshaft shredder offers the ideal conditions for direct processing of these large rolls - and without the need for prior preparation of the input material by employees before the material is fed into the recycling process", emphasizes Patrick Wiesinger. With the ISEC evo recycling machine TenCate can now manufacture its high-strength PP nonwoven product with a recyclate content of up to 10 percent.

According to the World Health Organization (WHO), cardiovascular disease is one of the most common natural causes of death. Every year, it is the cause of death of around 17 million people worldwide. The Peter Dornier Foundation Prize 2022 has now awarded a research work that is to improve the medical care of people with insufficient heart valve function in the future and prolong the patients' lives.

The human heart is a high-performance machine: over the course of a person's life, it beats almost three billion times, pumping around 200 million litres of blood through the body. Enormous stresses that can sometimes lead to life-threatening signs of wear and tear. If a heart valve gets out of step, patients usually get artificial-mechanical or biological valves as a replacement. However, mechanical solutions imply patients to take blood-thinning medication for the rest of their lives. In addition, there may be audible closing noises. For example, almost a quarter of patients with mechanical heart valves complain of sleep disturbances. Biological heart valves, on the other hand, such as those made from animal tissue, require a great deal of manual work and have a shorter lifetime.

Potential of weaving for medical products demonstrated
For this reason, Graduate Engineer Mathis Bruns at the Institute for Textile Machinery and High-Performance Textile Materials Technology (ITM) at the TU Dresden is researching an implant alternative made of fabric. As part of a research project that also involved heart surgeons from the Dresden Heart Centre and the University Hospital in Würzburg, Mr. Bruns provided important findings for weaving an artificial heart valve in his diploma thesis. For his work entitled "Development of tubular structures with integrated valve function", Mathis Bruns has now received the Peter Dornier Foundation Prize 2022, endowed with 5,000 euros. In his laudation, Dr. Adnan Wahhoud, former head of the development department of air-jet weaving machines at DORNIER in Lindau, said: "With his work, the winner of the award demonstrates very clearly the potential of weaving technology to produce fabrics of complex form, geometry and structure with the aim of prolonging and improving people's lives." The award-winning thesis enriches research into three-dimensional tissues for use in medicine.

Weaving replacement heart valves without seams
"A particular advantage of our approach is the integral production method", says foundation prize winner Mathis Bruns. “The geometry and function of a heart valve is that complex that woven heart valves could not be produced in this form previously. Through the combined use of a rigid rapier weaving machine with bobbin shield and a Jacquard machine, it is possible to weave the replacement heart valve in such a way that it no longer has be sewn together. Even the tubular structures for the blood vessels and the integrated valve function are ‘all of one piece’. Seams are always a weak point in textile medical products," Mr. Bruns adds. “Another advantage of the woven heart valve is the possibility to insert it by the help of minimally invasive surgery. Hence, the folded valve which is about the size of a tea light is to be pushed with a catheter via the bloodstream to the target position in the heart and unfolded there. The patient's chest and heart would then no longer have to be cut open”, explains prize winner Mr. Bruns.

Textile structure is similar to human tissue
A wide variety of medical products have always been produced on DORNIER weaving machines. Customers use them to produce fabrics for bandages, prostheses, blood filters and orthoses among other things. For Mathis Bruns, it is only evident that implants such as heart valves will more and more be woven on the machines from Lindau in the future. "Textile tissue is very similar to human tissue," he says. The human body consists largely of thread-like materials, just as a textile fabric is made up of thousands of individual threads. "Muscle fibres convey force impulses, nerve tracts send stimuli such as pain and brain cells convey information via thread-like dendrites and axons." Because of their ‘thread-like properties’, woven implants are therefore particularly suitable for medical applications.

After three years, VUB a.s again got the chance to actively participate in the European trade fair Techtextil 2022m being present at a joint stand of Czech companies active in production and application of technical textiles, organized by Clutex - Cluster Technical Textiles.

In cooperation with partners from academic and production sphere many products were developed over the past years, sold by VUB under the brand Clevertex. For the presentation at the fair, a wide range of ESD protective clothing for the electrotechnical industry and for each worker dealing with electrostatic discharge sensitive components was on display. As well as another product line of the Clevertex brand representing wearable skincare textile products with antiseptic effects based on purely natural textile materials.

Attention was paid to the advanced solutions for smart textiles and e-textiles products esp. electrically conductive hybrid threads based on ultrafine metallic micro-wires. A significant advantage of these threads lies in their full compatibility with standard textile manufacturing processes, and possibility of customization in terms of fineness, electrical conductivity and temperature resistance of individual thread. As an example of one of the applications of conductive threads, different types of woven elastic conductive ribbons were demonstrated, which could be used as bus bars or as textile conductors wherever a variable length of conductive element is required without the negative influence on their electrical resistance during the change the length.