STRUCTURE PROTECTION

EVONIK, operating silane production, research, and development for more than 60 years, provides suitable solutions for the requirements of structure protection with the PROTECTOSIL product group. Silanes add a significant level of strength and resistance. Furthermore, this process doesn’t show any side effects on the functions of the structure, nor are significant differences observed in aesthetic appearance. Many well-known buildings around the world are protected with PROTECTOSIL® structure protection products because these high-performance products protect against the problems listed below and more;

• Deterioration on reinforced concrete steel bars
• Weathering
• Salt and Sulfate attack
• Freeze-Thaw deformation
• Acid rain attack
• Mould, moss, and graffiti

PROTECTOSIL Product Groups can generally be classified into 5 categories;

• Water-Repellents
• Surface Protectors (Dirt retarder and easy-clean property)
• Corrosion control on concrete structures
• Anti-Graffiti Products
• Stone consolidation

Thanks to the wide product group range of PROTECTOSIL®, the most suitable product or product combination can be found for all kinds of applications and materials on either historical or modern structures, such as;

• Concrete
• Brick
• Natural Stone
• Mortar
• Sand-lime brick
• Marble & Granite

STONE CONSOLIDATION

PROTECTOSIL® SH

Protectosil® improves mechanical properties and hardens stones.

Evonik’s PROTECTOSIL® products protect the uniqueness and beauty of modern and historical buildings. PROTECTOSIL® SH is used to deposit silicic acid, formed as a result of complete hydrolysis. The resulting silicic acid bonds well with many mineral and inorganic surfaces such as natural stone, brick, or terracotta. The deposition of a thin SiO2 layer improves chemical and thermal stability as well as mechanical properties.

PROTECTOSIL® SH is used for stone consolidation on porous mineral substrates. It is applied in specially developed formulations depending on the type of natural stone.

Products:

• PROTECTOSIL® SH : Used for stone consolidation on porous mineral surfaces. Depending on the type of natural stone, it is applied in specially developed formulations.
• PROTECTOSIL® SH 100 : Eco-friendly, suitable for the consolidation of mineral construction materials, bricks, and terracotta. The product improves thermal and chemical stability and the mechanical properties of treated surfaces.
• PROTECTOSIL® WS 808 : Contains almost no solvents and is suitable as a water repellent for low-fired clay products (roof tiles, bricks, floor tiles, terracotta) as well as various natural stones, sandstones, and gypsum.

Anti-Graffiti Products

PROTECTOSIL ANTI-GRAFFITI

Protecting buildings against graffiti is difficult. This duty must be performed quickly, effectively, and economically. PROTECTOSIL ANTIGRAFFITI® and PROTECTOSIL ANTIGRAFFITI® SP are the most suitable products for this task. The more impressive and visible a building is, the more attractive it becomes for graffiti vandals. If the building is not protected, negative consequences are inevitable.

There is no room for vandalism on buildings protected with PROTECTOSIL ANTIGRAFFITI®. Spray paints do not adhere to the surface; they flow away, making it impossible to write. Consequently, the vandal gives up. If the surface is protected with PROTECTOSIL®, any graffiti applied can be cleaned effortlessly. Surface cleaning is quite easy with PROTECTOSIL® PROFICLEAN GEL. One of the most important properties of PROTECTOSIL® products is that they do not alter the building’s appearance.

PROTECTOSIL ANTIGRAFFITI® and PROTECTOSIL ANTIGRAFFITI® SP are hydrophobic and oleophobic products. Thus, surfaces protected with these products are resistant to dirt and oil. Neither solvent-based paints nor spray paints can penetrate the structural material pores. Since graffiti paints do not penetrate deep into the substrate, they simply flow away from the treated surface.

The graphic above demonstrates how effective the PROTECTOSIL ANTIGRAFFITI® product is against liquids and oils. Unlike other products, PROTECTOSIL ANTIGRAFFITI® does not seal the surface completely, allowing for water vapor transmission (breathability).

For PROTECTOSIL ANTIGRAFFITI®, nature was used as a model. Anti-graffiti applications are divided into 3 different classes: temporary, semi-permanent, and permanent systems. Temporary systems must be reapplied after each cleaning process. On the other hand, permanent systems can withstand more than 10 cleaning processes easily. The molecules of PROTECTOSIL ANTIGRAFFITI® chemically react with the surface and are durable against wear, ensuring long-term protection.

Application of PROTECTOSIL® is easy…

PROTECTOSIL ANTIGRAFFITI® is non-hazardous and can be applied quickly and easily using HVLP (high volume-low pressure) spray techniques. Various coatings may be needed depending on the type of structural materials. The drying time of these coatings ranges between 10 to 60 minutes, depending on weather conditions. Thanks to this, you can coat entire buildings and make them ready for protection in a single day, significantly decreasing workload. PROTECTOSIL ANTIGRAFFITI® SP is quite flexible in application; it can be applied using either HVLP spray techniques or with a brush and roller.

Environmentally friendly and solvent-free:

• Water-based
• Eco-friendly
• Very low VOC contamination (Volatile Organic Compounds)
• No HAP (Hazardous Air Pollutants)

PROTECTOSIL® PROFICLEAN PLUS

This is a very effective graffiti cleaner. Generally, graffiti is applied with spray paints. These kinds of paints can be cleaned very easily from walls where PROTECTOSIL ANTIGRAFFITI® or PROTECTOSIL ANTIGRAFFITI® SP have been applied. All that is required is PROTECTOSIL® PROFICLEAN PLUS, a brush, and pressurized water (<12 bar).

PROTECTOSIL® PROFICLEAN PLUS cleans graffiti paints thoroughly. Thanks to the low viscosity of the cleaner, neither the cleaner nor the dissolved graffiti paints are absorbed by the surface.

Even wide and exceedingly smooth concrete surfaces protected with PROTECTOSIL ANTIGRAFFITI® can be cleaned easily and quickly without the need for additional materials or high-pressure water.

Products:

• PROTECTOSIL ANTIGRAFFITI® : Suitable for porous mineral structural surfaces. It is a zero-VOC, silane-based, hydrophobic, and oleophobic anti-graffiti product.
• PROTECTOSIL ANTIGRAFFITI® SP : Suitable for porous mineral structural surfaces. It is a zero-VOC, silane-based, hydrophobic, and oleophobic anti-graffiti product. Its lifespan is shorter than Protectosil Antigraffiti.
• PROTECTOSIL® PROFICLEAN PLUS : Designed specifically to clean surfaces treated with Protectosil ANTIGRAFFITI®. Spray paint, lacquer, marker, or pen writings can be cleaned easily with this product.

Corrosion Resistance – PROTECTOSIL® CIT

Buildings, bridges, and multi-storey car parks are among the most significant private or public investments. However, reinforcement bars inside the concrete of these structures age and rust over time. This situation causes a loss of strength. If maintenance costs are high, it becomes a very difficult case to handle. The key to protecting these structures for a long time is keeping the surface away from water and chloride ions. Even if corrosion is observed on surfaces, applicable and suitable solutions can still be found.

PROTECTOSIL® CIT is a silane-based corrosion protection system and is one of the most excellent products of EVONIK. Like other PROTECTOSIL® products, PROTECTOSIL® CIT creates a durable and long-lasting barrier due to its deep hydrophobation property. It penetrates the applied surface and reacts with the concrete. It protects reinforcements in the concrete and stops the development of corrosion.

The most effective maintenance method is one that does not require any maintenance. That’s exactly why we recommend PROTECTOSIL® CIT not only for older concrete structures but also for newly constructed structures.

Water effect is the main problem harming structures. While struggling with weathering, this situation leads to freeze-thaw cycles and salt attacks. Yet, water is only one of the reasons for deterioration. The main reason for rusting of reinforcement bars in concrete and the occurrence of mechanical regression is chlorine. Water molecules react with concrete electrostatically; because of this reaction, chlorine transmission increases and bars start to rust.

PROTECTOSIL® CIT shows a resistance effect against both chlorine and water reactions. First of all, it creates a deep barrier blocking water and prevents chlorine ions from reaching reinforcements. After that, PROTECTOSIL® CIT blocks electrolyte current, resulting in a decrease in rusting. According to independent research, three products in the market used for corrosion protection cannot be truly effective against chlorine transmission* and cannot prevent rusting.

On the other hand, PROTECTOSIL® CIT effectively decreases the rusting rate according to ASTM-G109**.

* J.E. Bennett, Consultants Inc. / a research on rusting protectors due to ASTM G-109 procedures. / Report February 2004
** J.E. Bennett, Consultants Inc. / a research on Protectosil® CIT due to ASTM G-109 procedures / Report November 29, 2005

PROTECTOSIL® CIT was applied as a test on WJE Associates(1) concrete reinforcement bars which have cracks approximately 0.3 mm wide. Some specimens were protected with PROTECTOSIL® CIT before wet and dry cycling. Wet and dry procedures were performed with a 15% NaCl solution. Other specimens were left unprotected. After 12 weeks, at the end of the test, corrosion and rust could be observed on unprotected specimens. By comparison, active corrosion or rusting was not encountered on specimens protected with PROTECTOSIL® CIT.

Determining any corrosion occurring on reinforcement bars before serious and irrecoverable damage arises on the concrete is very important. The most efficient way to determine corrosion at the beginning is by measuring chlorine contamination or electrical potential/voltage difference. There are some useful in-situ measurement devices, for example, linear polarization equipment.

The graphics given below show the correlation between corrosion rate and periods of visible rusting. After corrosion on reinforcement bars, the application of PROTECTOSIL® CIT products is an effective solution.

Model Application: “Monroe County Multi-storey Car Parking”

Conditions are very tough in multi-storey car parks. In 1996, the corrosion rate was determined and measured via tests in the Monroe County Multi-storey Car Park, a 30-year-old building located in Pennsylvania, USA. The corrosion rate showed high corrosion occurring on reinforcement bars. If results are below 0.2 µA/cm², there is no active corrosion risk. However, in case results are above this limit, the concrete structure can be damaged.

The corrosion rate on the Monroe County Multi-storey Car Park was 0.68 µA/cm² before the application of PROTECTOSIL® CIT, posing a danger. This happens mostly in winter because of salts—ice-breakers—brought in by car tires. After the application of PROTECTOSIL® CIT, the rate mentioned above decreased to under the level of 0.1 µA/cm². Although 11 years have passed, re-application has not been required. The protection is still maintaining its performance.

Model Application: “Application on Columns of Galleria Cianca Presella”
Sensors measured recent and potential corrosion. For a more detailed analysis of measured values, the rusted steel amount was calculated. It helped to estimate developments in corrosion damage. From the point in time after PROTECTOSIL® CIT was applied, the protected surface showed less corrosion development. Then, the protected column reached a specific passive corrosion level and stopped (tag p). Active corrosion was observed on the unprotected surface (tag a).

Products:

• PROTECTOSIL® CIT: Significantly decreases chloride-based corrosion of reinforcing steel bars in concrete due to the reaction of the active material of the cement phase with the steel surface.
• PROTECTOSIL® DRY CIT: A powder protection product. PROTECTOSIL® DRY CIT has been honored with many awards and is the first solid protection additive for reinforced concrete corrosion.
• PROTECTOSIL® WA CIT: Protects especially reinforced concrete, cast concrete, and prefabricated concrete members from chloride-based corrosion. The product dissolves homogeneously inside the concrete, and protection shrinkage decreases.