WACKER will unveil a new dispersible polymer powder that has little tendency to flow and can be used to formulate high-performance waterproofing membranes that are easy to handle. VINNAPAS® 7150 E confers pronounced non-slump properties on waterproofing membranes and so can be easily applied with a notched trowel. The European Coatings Show 2019 will be held in Nuremberg, Germany, from March 19 to 21.
Waterproofing membranes are barrier layers which are based on cement mortars and have a high content of polymeric binders (up to 30 percent). They are used to protect cellar walls, terraces and bathrooms against penetrating moisture. After they have been applied, they can be covered with other, appropriate materials, e.g. tile adhesives and tiles in wet rooms, and bituminous sheets on flat roofs. The binders are also highly adept at bridging cracks in masonry, as the high content of dispersible polymer powder makes the layer flexible as well as waterproof. This prevents cracks from spreading from the substrate to the surface and from allowing moisture to penetrate.
In German-speaking countries, waterproofing membranes are usually applied with a notched trowel. The ease with which the cement-polymer mixture can be troweled depends heavily on its rheology, i.e. flow properties. For, it is the rheology which determines how much the cement mortar slumps – and thus whether the ribs produced by the notches of the trowel remain standing or collapse after application.
Previous dispersible polymer powders were unable to impart the non-slump properties needed for application with a notched trowel. So WACKER chemists set about modifying the recipe for the dispersible polymer powders. This culminated in VINNAPAS® 7150 E, a new binder that has vastly improved rheological properties.
VINNAPAS® 7150 E consists of a combination of vinyl acetate-ethylene polymers and vinyl esters which has been modified with newly developed protective colloids and silicon dioxide particles. As a result of this modification, spray drying of the dispersion yields a powder which, in the ready-for-use sealing compound, imparts a more stable rheology and boosts its non-slump properties.
A further bonus is that the waterproofing membrane is less tacky and so does not cling as much to the trowel. Instead, it stays where it belongs – on the floor or wall. It is thus easier for the craftsman to apply it in a layer thickness of two millimeters, which is mandated in German-speaking countries by the German “PG-MDS” waterproofing-membrane standards. Furthermore, by virtue of their low glass transition temperature, waterproofing membranes containing the new WACKER binder are capable of bridging cracks at temperatures down to minus five degrees Celsius, as determined per EN 14891.
“Our newly developed dispersible polymer powders manage to perform quite a balancing act,” says Frank Reichle, head of the Construction Polymers Western Europe business team at WACKER. “They hold all the particles together in an intact polymer film while bestowing the necessary flexibility on the matrix. This combination of what are really two mutually exclusive properties makes VINNAPAS® 7150 E the optimum binder for formulating high-performance waterproofing membranes that are easy to process, especially in German-speaking countries where trowels are the preferred tool.”
As VINNAPAS® 7150 E is free of solvents, plasticizers and film-forming agents, it has the added bonus of not emitting any volatile organic compounds (VOCs). With VINNAPAS® 7150 E, it is possible to formulate recipes that have very low emission values (placing them in the EMICODE® EC1 emissions category of the Association for the Control of Emissions in Products for Flooring Installation (GEV)); the dispersible polymer powder has even been approved by the Federal Institute for Risk Assessment for drinking water applications.
Source: Wacker Chemie AG
New at ECS 2019: The WACKER Forum
WACKER will be devoting a total of 240 square meters of floor space to solutions for paints and coatings, and construction and adhesives applications at the European Coatings Show 2019. More than 70 experts will be on hand at Booth 1-510 in Hall 1 to discuss the products and their applications with interested parties. Making a new appearance this year will be the WACKER forum, right beside the main booth. Here, 15-minute presentations aimed at an international specialist audience will be held on technology, trends and innovations under the motto “Let’s talk about…” More information about the program of presentations in the WACKER Forum can be found at www.wacker.com/ECS2019 soon.
About WACKER POLYMERS
WACKER can look back at over 80 years’ experience in the manufacture of polymer binders. Today, WACKER is a leading producer of state-of-the-art binders and polymeric additives based on polyvinyl acetate and vinyl acetate copolymers. These take the form of dispersible polymer powders, dispersions, solid resins, and solutions. The products are used in construction chemicals, paints, surface coatings, adhesives and nonwovens, as well as in fiber composites and polymeric materials based on renewable resources. WACKER operates production sites for polymer binders in Germany, China, South Korea and the USA, as well as a global sales network and technical centers in all major regions.