SBS modified asphalt waterproofing roll-roofing material has superior performance and low cost, and can be widely used in buildings, highways and bridges and other projects.
The manufacturing process of sbs waterproofing roll-roofing materials are (1) in high temperature and high humidity environment. (2) using heat treatment. (3) used at high temperatures. (4) decomposition of various chemical components.
In modified silicone, polyether, polyester, aralkyl and other organic groups are combined with the main chain of polysiloxane in two forms: silicon-carbon bond (Si-C) connection or silicon-oxygen-carbon bond ( Si-OC) are connected. Silicon-oxygen-carbon bonds are easy to hydrolyze, especially in acid or alkaline media. After hydrolysis, silicone oil and organic segments or groups are formed. Silicone oil will cause film shrinkage and poor recoatability. Therefore, the Si-O-C structure is undesirable, and the Si-C chain has better hydrolysis resistance than the Si-O-C chain. Therefore, the organic chain or group in the modified silicone The connected structure is mostly silicon-carbon bond structure.
When modified silicone is used as an anti-crater and leveling agent, there are certain requirements for the amount of use. If the amount is too large, it will produce side effects, such as shrinkage, poor recoatability, decreased adhesion between layers, and film coating. Fog, etc. This is because when the amount of silicone is within the appropriate range, it can be evenly distributed in the coating.
After coating, due to its low surface tension, it will quickly migrate to the surface of the coating film to form a very thin film. The formation of incompatible droplets stay on the substrate and cause shrinkage; at the same time, the modified silicone film (except reactive silicone) will not stay on the lower layer due to the uniformly covered modified silicone film (except reactive silicone) when the coating film surface is recoated The surface of the coating film instead migrates to the surface of the upper coating film. Therefore, there is no modified silicone between the two coating films, so there is no negative impact on the adhesion between the layers and the gloss and smoothness of the coating film. When the amount of modified silicone is too high, some silicone molecules cannot migrate but still stay on the surface of the underlying coating film, which reduces the adhesion between layers. Excessive modified silicone will also generate insoluble droplets and cause the coating to shrink. hole. Therefore, carnauba wax excessive use of such anti-crater and leveling agents will not bring additional benefits to improve the wettability, anti-crater and slip properties, but will cause many side effects. Therefore, it should be based on the specific coating product. To determine the variety and optimal dosage of anti-cratering and leveling agents through experiments. Table 8-11 reflects the effect of polyether-modified silicone dosage on the adhesion between acrylic polyurethane coatings.
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