Skip to main content
Sister Publication Links
  • Middle East Foam & Polyurethane
  • UTECH Asia/PU China
  • UTECH Europe
  • UTECH Las Americas
Subscribe
  • My Account
  • Login
  • Subscribe
  • Coronavirus
  • News
    • Asia
    • Americas
    • Europe
    • M & A
    • Financial results
    • Automotive
    • MPOB develops palm oil polyol
      BPCL Polyol project in doubt
      Japan's lacklustre PU production continued in November 2020
      PU prevents freezing damage to railway tunnels
    • World automotive registrations recover in H2 2020
      Mlily to increase US market share following anti-dumping duties
      US footwear imports up 25% in November 2020
      Introducing UTECH Southeast Asia 2022
    • Wheat waste transformed into PU foam
      EC approves Kingspan's TeraSteel and Wetterbest purchases
      BTC Europe to distribute BASF’s polyurethane ingredients
      World automotive registrations recover in H2 2020
    • BPCL Polyol project in doubt
      PPG buys polyurea company Versaflex
      Recticel buys FoamPartner
      Recticel upgrades Q3 outlook despite raw material tightness
    • BPCL Polyol project in doubt
      Huafon estimates 2020 profit will be up to 40% higher than 2019
      Mlily to increase US market share following anti-dumping duties
      Stellar Q4 performance saves Wanhua 2020 earnings
    • World automotive registrations recover in H2 2020
      Car sales down 25% in Western Europe in 2020
      Patchy coronavirus effects hit global car sales in November
      November continues fall in Western Europe's car sales
  • Data
  • Information
    • Country Overview
    • Market Sector overviews
    • Technical articles
    • Company profiles and strategies
    • China’s PU industry on the path to recovery; plans for technology upgrades
      Chinese cold chains grow bigger
      Flexible foam rises to challenges in the Middle East and Africa
      Life at the cross-roads: what does the GCC offer PU?
    • Europe's flexible foam makers face rising prices as outages hit markets
      Western European car registrations rebound slowed in September
      Western European car registrations regained some ground in August
      Western European Car registrations rebound continued in July
    • Take out the VOC with hybrid release agents
      Batteries give pultrusions power
      Seeing a way through VOC and FOG
      Aromatic polyols for simpler rigid PU formulations
    • Hennecke and Frimo: an automotive partnership
      Pushing ahead: AutoRIM drives KM’s UK growth
      BASF opens it first ‘Creation Center’ in Mumbai with a PU twist
      Persistence pays off for CTM
  • Events
    • Exhibitions
    • Conferences
    • Webinars / Livestreams
    • Become a Speaker
  • Advertise
  • Contact Us
  • Issues
  • Subscribe
MENU
Breadcrumb
  1. Home
  2. Information
December 20, 2016 11:00 PM

FSK looks across European PU foam technology

Simon Robinson
  • Tweet
  • Share
  • Share
  • Email
  • More
    Print

    Germany's FSK foamed polymers association held its annual meeting in Bad Durkheim, and at BASF's plant in Ludwigshafen, Germany. Simon Robinson visited the heart of Germany's Rhineland-Palatinate wine growing region to report.

    The FSK is a very broad church, and this was reflected at the meeting which covered papers on subjects as diverse as multifunctional surfaces made using expanded polypropylene foam and several papers on foams made from melamine resin. But the bulk of the presentations were about polyurethane foam in one form or another.

    The polyurethane section started off with Frank Prissok of BASF, who explained how micro-cellular foams made of thermoplastic polyurethane are finding use in the Adidas Boost footwear technology.

    FSK meeting Bad Durkheim, Germany

    Prissok said the material is very good at  returning energy to runners. When the runner’s foot hits the ground, he explained, an "air cushioning effect makes the cells feel extremely soft at the first moment of compression. But it becomes increasingly stiffer as the stride continues. While jogging, it initially dampens and cushions the impact of the foot”.

    The material at the heart of innovation, he said, is a butanediol chain-extended TPU, which is foamed into particles about 1 cm in diameter using a proprietary technique. The TPU can be tuned to give a hardness of between Shore A 45 and Shore D 85, Prissok claimed.

    The material has low hysteresis, giving a high rebound, resulting in an energy gain for the runner. Longer distance and marathon runners will benefit most from the hysteresis performance of the foam, he explained.

    The foams are processed between 100° and 140°C, a temperature range that puts the processing window firmly in the realm of standard steam sintering machines.

    Prissok added that, depending on the level of fill of the mould and pressure applied, the materials can be used to make open or closed cell foams for large surface components.

    Frank Prissok

    During the moulding process, a pneumatic effect helps develop the bubbles and particles, and leads to the expansion of the material into the shoe. The density of the material falls from about 1100kg/m³ pre-moulding to around 100kg/m³ after moulding, he added.

    A typical foam has more than 95% closed cells, and a rebound greater than 60%, which Prissok claimed is much better than equivalent EVA materials.

    He added that, once moulded, material, tensile strength higher than 700kPa, and extension break generally above 200% can be produced.

    Insulation starts to gel

    Another presenter from BASF, Marc Fricke, explained to delegates the properties and benefits of polyurethane aerogels. These, he told delegates could "create completely new possibilities in terms of work and application".

    Marc Frick

    He explained that his firm’s recently commercialised Slentite aerogel is a high-performance material designed for use in thermal insulation. Aerogels are very insulating, he said, but added that traditional aerogels are brittle and difficult to handle successfully.

    The Slentite materials are produced by a controlled liquid phase chemical reaction that gives a three-dimensional polyurethane network. After the reaction is complete, the gel must be carefully dried, while maintaining the highly porous structure and without loss of volume.

    The BASF material has lambda the value of 17 mW/mK which is "an unprecedented insulation performance” Fricke claimed. “With this material, a 20 to 25% thinner insulation is possible requiring less space, particularly for subsequent insulation," he added.

    He explained that the "unprecedented thermal insulating properties of aerogel results from the interaction between small pore sizes and large internal surfaces in the network structure".

    Conventional insulation materials based on other types of foam have cells that are more than 1000 times larger than the gases that the cells contain. In these foam cells, gas molecules have enough space to transfer their kinetic energy to each other, and to the foam. The collisions are converted to heat, and this is transmitted through the foam, he explained.

    "The pore structure in aerogels is at about the same size as the mobility range of an individual gas molecule, so that heat transfer by collision is significantly reduced,” he said. This effect can be experimentally proven, and is why aerogels have lower thermal conductivity than air, even though the pores are filled only with air, Fricke explained.

    Stick around

    Marcus Korner explained that the change in foam properties has been a constant source of challenges for his employer, Henkel, which makes adhesives for a range of materials.

    A number of requirements are placed on modern foam adhesives. The most important of these are easy processibility, and non-toxicity during processing and use. Additionally, when they are applied, they must produce adhesive layers that have good flexibility, good temperature and chemical resistance, as well as long-term ageing stability.

    Korner said solvent-free adhesive systems have become increasingly important in mattress and furniture manufacturing. Hot melt and water-based dispersion adhesives are increasingly being used, he added. Korner suggested that polychloroprene latex adhesives represent a valid alternative to solvent based adhesives. This is because latex polymers coagulate under the mechanical stress caused by joining foam pieces, giving good initial tack.

    In most cases, this initial tack is enough to permit further handling of the parts, and the final strength is achieved when the film is completely dried. Therefore, he said, with comparatively simple and cost-effective application methods it is possible to generate glued joints with properties comparable to those of solvent-based adhesives. But, he warned, the bonded parts must dry for several hours before packaging to prevent mould formation in the finished product.

    Korner suggested that hot melt technology, where polymers are melted to temperatures between around 130°C and 170°C to reduce the material’s viscosity sufficiently for it to be used, is a valid alternative to non-solvent adhesives. Hot melt adhesive can be sprayed or extruded onto the polyurethane substrate, he said.

    Hot melts, he continued, reach their final strength quickly on cooling. However, hot melt adhesives often become brittle when they cool, and he claimed this has led to problems with delamination, and bonded seams coming apart in the mattresses.

    Another disadvantage of this adhesive technology is the relatively high capital investment needed to buy the application equipment, he said.

    Alfons Wurm and Felix Zimmerman from cutting machinery firm Albrecht Baumer told delegates about some of the developments in producing mattresses and upholstered furniture. They said that this is "strongly characterised by the bringing together all bonding of very different materials". They went on to give an overview of current trends in the sector.

    Standards and safety

    The machinery theme continued with Rudiger Simon of Sitola, who took a German perspective on industrial health and safety regulations. These were updated in June 2015, and have resulted in a significant change in the way that older machinery is treated.

    Rudiger Simon

    He warned delegates that grandfathering — which means that if a machine was compliant with health and safety standards when it was commissioned it will be measured against those standards in subsequent health and safety reviews — no longer applies.

    All work equipment "must at least meet requirements of the industrial health and safety regulation of 2015, he said. Risk assessment is a key element to this regulation, and this must take place before selecting and purchasing work equipment.

    Simon added, "It has to be designed in before purchase. [The regulation] assumes that the person conducting the risk assessment is competent to do so, and if the employer doesn't have the necessary expertise… then it must be done by a qualified person."

    The polyurethane papers were rounded off by a presentation from Mark Martin of BASF, which explained his company’s simulation system for semi-rigid systems used in automotive applications such as instrument panels and covered in Urethanes Technology International in October/November 2016.

    Also at the conference, Lars Nelles outlined Fecken-Kirfel’s process optimisation technology (Urethanes Technology International September/October 2016).

     

    Recommended for You
    EU production growth heads eastwards
    EU production growth heads eastwards
    Making the case for TPUs
    Making the case for TPUs
    From cell to slope
    From cell to slope
    Latest Issue
    Click HERE for Free Download
    View All Archives
    Get our newsletters

    Breaking news and in-depth coverage of essential topics delivered straight to your inbox.

    Subscribe today

    Register to access our archive of leading information on the polyurethanes industry.

    Subscribe now
    Connect with Us
    • Twitter
    • LinkedIn
    • Facebook
    • Youtube

    Follow us on social media for the latest polyurethanes industry news and event updates.

    Logo
    Contact Us

    Office 127,
    61, Willow Walk,
    London
    SE1 5SF
    E-mail us
    +44 (0) 203 287 5979

    Customer Service:
    +1 313 446 0450

    Resources
    • Advertise with Us
    • Media Kit
    • Staff
    • Careers
    • Ad Choices Ad Choices
    • Sitemap
    Legal
    • Terms and Conditions
    • Privacy Policy
    • Privacy Request
    Copyright © 1996-2021. Crain Communications, Inc. All Rights Reserved.
    • Coronavirus
    • News
      • Asia
      • Americas
      • Europe
      • M & A
      • Financial results
      • Automotive
    • Data
    • Information
      • Country Overview
      • Market Sector overviews
      • Technical articles
      • Company profiles and strategies
    • Events
      • Exhibitions
      • Conferences
      • Webinars / Livestreams
      • Become a Speaker
    • Advertise
    • Contact Us
    • Issues
    • Subscribe