All kinds of curtain walls, such as stone curtain walls, aluminum curtain walls, glass curtain walls, etc., may have curtain wall pollution. So, what causes these pollutions? Is it because of improper selection of sealants? How to solve and prevent them?
The manifestations of curtain wall pollution can be mainly divided into two categories: penetration pollution and vertical flow pollution. The manifestations of these two types of pollution are different, and the causes and solutions are also different. In this issue, we will first introduce the relevant content of penetration pollution.

1. Manifestations of penetrating pollution

    The manifestation of penetrating pollution is that the panel material in contact with the glue joint has oil-like substances infiltrating, causing the surface of the panel material to change color. This phenomenon generally occurs in the panel material adjacent to the glue joint, and is more common in stone curtain walls. In addition, porous curtain wall materials such as ceramic panels and fiber cement boards have also been found to have penetrating pollution in engineering cases.

    In addition, some curtain wall projects use decorative materials such as aluminum panels and aluminum-plastic panels with coated surfaces, which also experience penetration pollution. The oily substance penetrates and spreads on the surface coating of the panel material, and the pollution area is large. The pollution phenomenon is very obvious, seriously affecting the appearance of the curtain wall.

    The joint sealant for porous plates such as stone and ceramic curtain walls must be a special stone sealant, and the product should comply with the national standard GB/T 23261 "Stone Construction Sealant". Some manufacturers' sealant products on the market claim to be stone sealants, but in fact they do not comply with the national standard GB/T 23261 "Stone Construction Sealant". At present, there are still a considerable number of sealants filled with mineral oil on the market. Due to the large difference in the chemical composition of the organic silicon polymer of mineral oil and silicone sealant, it is possible to migrate out of the colloid in a short time after the sealant is used, and penetrate into the interior of the porous material, forming penetration pollution. This type of sealant product cannot be used to seal the joints of porous plates such as stone.

2. Penetration pollution of coated aluminum plates and aluminum-plastic plates

    The penetration pollution of decorative materials such as aluminum plates and aluminum-plastic plates with coated surfaces is mainly due to the poor aging resistance of the surface coating. The coating becomes loose and powdery after aging, so the plasticizer in the sealant penetrates into the aged coating and forms a penetration diffusion on the coating surface. This kind of penetration pollution will be more obvious on light-colored aluminum plates, aluminum-plastic plates or other light-colored decorative materials than on the corresponding dark-colored materials, so more attention should be paid when using them.
    The general method for this kind of penetration pollution is to repaint and refurbish the panel. However, it is difficult to clean the pollution of the coating after the sealant plasticizer diffuses to the powder.

    For this type of problem, Baiyun Technology recommends: When selecting curtain wall panel materials, panel materials with good aging resistance should be selected; for panel materials with surface coatings, the surface coating should also have good aging resistance. Especially for light-colored aluminum plates, aluminum-plastic plates or other light-colored decorative materials, higher requirements should be placed on the durability of the surface coating and the anti-pollution property of the sealant.
Before use, customers should confirm the durability of the panel material and surface coating with the material supplier in advance, and send the materials to the sealant manufacturer or relevant third-party testing agency to test the compatibility and contamination of the sealant and the material.

    Baiyun brand SS818/SS518 anti-pollution silicone weather-resistant sealant is an environmentally friendly, alkoxy, neutral curing sealant, specially designed for anti-pollution and weather-resistant sealing of various curtain walls (glass curtain walls, aluminum curtain walls, stone curtain walls, etc.). It has no penetration pollution to porous materials such as stone and decorative materials such as aluminum plates and aluminum-plastic plates with coatings on the surface, especially for some light-colored aluminum plates, aluminum-plastic plates or other light-colored decorative materials, its advantages are more obvious.