Dispersible Polymer Powders
At a Glance
Polymer binders have been used for improving mortars since the 1930s – but it was
only the pioneering development of the patented dispersible polymer powders in WACKER
labs in 1957 that ensured their real breakthrough and made it possible for the first
time to produce polymer-modified dry mortars. Now, WACKER is the world market leader
in dispersible polymer powders, which are sold under the brand name
VINNAPAS®. VINNAPAS® dispersible polymer powder are manufactured at WACKER sites on three continents. Optimum product availability, technical support and service are ensured by about 100 subsidiaries, sales offices and technical centers worldwide.
VINNAPAS® dispersible polymer powders are copolymers and terpolymers, such as vinyl acetate-ethylene (VAE) and vinyl acetate-vinyl chloride-ethylene (VAc-VC-E). They combine the functionality of polymer dispersions with the processing advantages of a powder. As co-binders in cementitious dry mortars, VINNAPAS® dispersible polymer powders provide improved adhesion, flexibility and processability as well as, depending on the grade, extra properties, such as thixotropy, outstanding flow properties and water repellency.
Dispersible polymer powders are powdery products and therefore feature a number of advantages:
- they are ideal for ready-to-use dry mortars and prevent errors during mixing on site
- they permit easy transportation and storage of the dry mortars
- they ensure easy handling on site
VINNAPAS® dispersible polymer powder have been continually improved ever since they were invented. This continuous development ensures that they are optimized for present and future requirements. The innovative VINNAPAS® product class systems from Standard to Plus provides you with the suitable product for your specific application.
Dispersions usually have a particle size of 0.1 to 5 µm. Spray drying causes many individual dispersion particles to clump together into dispersion powder grains. The protective colloid matrix separates the dispersion particles (~1µm) in the powder particles (~100 µm) from one another and prevents the polymer particles irreversibly forming a film during drying and storage. The spray-dried powder is treated with antiblocking agent, which prevents the powder particles sticking together during storage.
As soon as the dispersible polymer powder comes into contact with water, the dispersible polymer powder grains disintegrate and release the individual dispersion particles again. The dispersed polymer powder has the same properties as the original dispersion – and that creates the right binders for better building.
In the hardened cement, the dispersion particles form a bridging polymer film and so act as an additional binder. The term used is "improved cohesion." At the same time, they form bridges to the substrate, thus improving the adhesion of the mixed mortar to the substrate.