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. Especially some small companies, in order to pursue high profits, add low-priced raw materials to the formula, so that 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. Here are some tricks for judging without an instrument.
Put the sealant on the blank paper, fold it in half, grind the glue flat, 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.
Different quality glues have different gloss after they are printed. High-quality glues have strong gloss after curing, and some low-quality glues have no gloss after they are cured, and some lose their gloss after curing for one or two months.
3. Check the particles
High-quality silicone sealant is a chemically synthesized material that has been fully and evenly stirred. It has a fine and uniform texture and is smooth and shiny after sizing and curing. The worse the quality of the silicone sealant is, the more particles and impurities will be seen, and the surface of the adhesive strip after sizing and curing is not as smooth and flat as the good quality glue.
4. Look at the bubbles
The main component of high-quality silicone sealant is silicone. 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. It will not cause air to be mixed into the bottle during sizing. The phenomenon of "pop, pop" bubbles occurs when glue is used.
5. Check the curing effect
After partial application of glue, the user should first check the surface drying time of the silicone sealant in accordance with the instructions on the product package. If the time is too short or overtime, it means that the quality of the silicone sealant is problematic (of course, the environment should also be considered The influence of conditions); then after the curing is completed, test the hardness and elasticity of the glue by hand. If the sealant is too hard or soft, it is not a good sealant; then see the cross section of the glue to check whether the curing effect of the glue inside and outside is consistent.