The Sweet Smell of Success
Furnace Chamber Test: Pictures from a furnace chamber test – in accordance with the DIN 4102-1 standard – at WACKER’s carpet laboratory in Burghausen. Films made with both VAE and SBL were tested, each time including 150% calcium carbonate as a filler. The images at the top show that the VAE-based films are self extinguishing (1A, 1B), whereas films made with SBL burn readily, issuing black smoke (2A, 2B). VAE-based binders therefore allow formulations that need fewer flame retardant additives.
Increased Flame Retardance
Since every carpet manufacturer has their own recipe adapted to existing equipment, Dr. Künstle and his team collaborated with Edel Group’s technical experts to create the optimal VAE carpet binder formulation for each carpet type. Künstle’s team also tested the ready-coated carpet specimens under practical conditions. He used machines that simulate shoes walking over the carpet thousands of times or the repeated rolling of office chair casters.
Dr. Künstle was particularly impressed by the tests carried out in his lab’s combustion chamber. During this test, he set fire to films of carpet backing compounds, some made with VAE, some with SBL. He observed that VAE films are less flammable than SBL films. In the case of certain f lame-retardant VAE grades, the fire was even self-extinguishing, whereas compounds formulated with SB latex burnt completely, releasing black smoke in the process. If the backings are bonded with VAE binders, much less flame retardant additive,such as aluminum trihydroxide, has to be added. On account of their relatively low flammability, carpets with a VAE backing are therefore ideal for commercial installations, such as in hotels and offices, or in aircraft construction and shipbuilding, where fire safety is a high priority.
“Our tests showed that in the case of a VAE carpet backing, the total emissions of volatile organic compounds are much lower than when SB latex is used”
Dr. Mike de Lange
Operations Manager, Edel Backing
Successful Collaboration: Dr. Mike de Lange (Edel Backing operations manager), Feike van der Heide (business director for WACKER POLYMERS’ dispersions business in EMEA), Robert Tangelder (business development manager for WACKER POLYMERS’ dispersions business in EMEA) and Willem van der Meer (Edel Group purchasing manager)
Low VOC Emission Values
The benefits of VAE dispersions reveal themselves in emissions testing, too. Since their surface area is large, floor coverings have the potential to emit volatile organic compounds (VOCs) to the environment. The Association of Environmentally Friendly Carpets (GUT e.V.), an initiative launched by European carpet manufacturers, has established the “GUT” label. To receive this label, carpets must undergo extensive analysis for possible pollutants and must meet rigorous standards. These carpets are tested, among other things, for plasticizers, biocides, pesticides, aromatic compounds, hydrocarbons, aldehydes (e.g. formaldehydes) and ketones. Additionally, a sensory odor test is performed. “Our tests showed that in the case of a VAE carpet backing, the total emissions of volatile organic compounds are much lower than when SB latex is used,” says Dr. Mike de Lange.
In Europe, there had been a long tradition of making carpet backings to similar formulations. After all, the carpet business is all about products that need to endure a great deal for many many years. So, it was an obvious step to turn to time-tested processes. Tradition is a cornerstone of Edel Group’s corporate philosophy, too. The family-run business, with its 120-strong workforce, has been making carpets at its base in Genemuiden, Netherlands, for almost 100 years. Not satisfied with standing still, Edel Group is always looking to improve. One example is the development of carpets made with recyclable raw materials.