Bubble formation on epoxy flooring commonly occurs on the first floor or basement, and occasionally on floors above the second. Bubbles often appear shortly after installation, with some epoxy flooring developed bubbles as early as the afternoon following morning installation. The bubbles grow from small to large, and their growth stops at a certain point. Higher temperatures increase the likelihood and speed of bubble formation. Bubbles come in various shapes and sizes, with some reaching diameters over 1m and heights of 20-50mm. There is no apparent correlation between bubble formation and the construction area, as some areas may have severe cases while others are less severe, with some remaining intact. The same group of workers using the same materials for the epoxy flooring may have some areas with bubbles and others without, indicating that bubble formation is caused by multiple factors.
The cause of blisters is a commonly asked question. Upon cutting open a blister, it is found that the inside contains water or a yellowish liquid. The epoxy ground layer detaches from the base layer, and the adhesive material stuck to the base layer is stretched into a cellular structure. In a sealed container filled with liquid, evaporation occurs, forming a saturation state with three curves depicting the relationship between temperature and pressure. Inside a sealed container, the pressure of saturated steam increases with rising temperature. At 20°C, the pressure inside a blister is 0.01 MPa; between 70 to 80°C, it rises linearly to 0.1 MPa. In many regions, during the hot summer, the ground radiation heat can reach about 70°C. At such high temperatures, the epoxy adhesive material softens, and its adhesion significantly decreases, causing it to expand like gradually inflating a tire, resulting in large blisters in the epoxy ground layer. The parts without blisters in the epoxy layer and ground are not firmly attached. Upon close observation of the contact area, one can also find parts that have not cured properly. The reason is that moisture in the epoxy prevents curing. So, where does the moisture come from?
There are mainly several sources of water:
1. At the base level, such as the leveling layer made of cement mortar, the moisture content reaches about 12%, with the base layer having a higher moisture content than the leveling layer.
2. Inadequate dehydration in other ingredients within the epoxy.
3. Poor adhesion during the application of epoxy and basecoat can result in gaps, as well as the chemical reactivity of the epoxy itself. This may lead to incomplete curing or residues or gases that haven't fully cured due to moisture exposure.
4. Ground-level gas infiltration from underground. Therefore, to minimize various issues at the construction site, please choose high-quality products and professional construction teams.
