Due to its superior performance, the demand for silicone sealants has increased by more than 20% every year since the 1960s. As a result, many companies have invested in the silicone manufacturing industry, resulting in uneven product quality. In particular, some small enterprises, in order to pursue high profits, have added low-priced raw materials to the formula, which makes the quality of silicone sealant cannot be guaranteed. Many construction sites do not have professional testing equipment, and it is difficult to judge the quality of the product. Now I will introduce a little trick that can be judged without using an instrument.

1. Appearance: glue to blank paper, fold it in half, grind down the glue, observe whether the glue is even and fine, whether there are mechanical impurities, whether there are bubbles, etc., high-quality colloids are generally uniform and fine, without mechanical impurities.

2. Specific gloss: the gloss of different quality glues will be different after being printed. No matter what color the high-quality glue has a strong gloss after curing, some low-quality glues will have no gloss as soon as they are cured, and some will lose their gloss after curing for one or two months. luster.

3. Check the particles: high-quality silicone sealant is a chemically synthesized material that has been fully and evenly stirred, with fine and uniform texture, smooth, smooth and shiny after sizing and curing. The worse the quality of silicone sealant is, the more particles and impurities will be seen. The surface of the adhesive strip after sizing and curing is not as smooth and flat as that of good quality glue.

4. Look at the bubbles: The main component of high-quality silicone sealant is silicone, and the amount of other additives is very small. The good stability of pure silicone is minimally affected by changes in external conditions during the storage period, and no bottles will be produced during sizing. Air is mixed in and the glue is sprayed out to produce the phenomenon of "pop" and "pop" bubbles. However, since the glue of ordinary quality silicone glue is not 100% silicone, the additives in the silica gel and the PE soft glue of the plastic bottle may have a chemical reaction, which will cause the plastic bottle to swell and increase, and the remaining air in the space can penetrate into the glue. Make it create a gap, and make a "pop, pop" bubble sound when glue is applied, which shortens the shelf life. What's more, a few manufacturers deliberately put the bottom cap on the bottom of the bottle when filling the glue, and there is air in the middle of the bottle, which greatly reduces the amount of glue, and it is inevitable that the glue that comes out naturally has bubbles.

5. Inspect the curing effect: After applying partial glue, the user should first check the surface drying time of the silicone glue in accordance with the instructions on the product packaging. If the time is too short or the timeout is too much, it indicates that the quality of the silicone glue is defective (of course The influence of environmental conditions should also be considered); Then, after curing is completed, test the hardness and elasticity of the glue by hand, and the glue that is too hard or too soft is not a good glue; then the cross section of the glue can be cut to check the curing effect inside and outside the glue. Is it consistent

6. Test tension and adhesion: The tensile strength and peel strength (adhesion) of the cured silicone adhesive are also different due to the difference in the quality of the silicone. The high-quality glue has extremely strong tensile force, large stretch range and high peel strength.