Acid silicone sealant (1)

1. Acidic glue bottles will be tall, deformed and even have oil after being stored for a period of time. Why?

There are two reasons for this problem, which are related to both the glue and the bottle.

First, the reason for the glue. Now on the market of acidic glue, in addition to a few high-grade glue, other acidic glue are different degrees of adding a certain amount of filler to reduce the cost, and the lower the grade of the glue, the more filling agent, and the filling agent will react with the bottle, so that the bottle length, deformation and oil; Such as high-grade glue may make the glue bottle after 6 months to have a reaction, the lower grade glue may have a reaction within 6 months.

Second, the reason for the plastic bottle. The quality of the material of the plastic bottle itself is also the reason for the growth. The raw materials used for the bottle body are good or bad. If the raw materials are good, the trend of the change of the plastic bottle is relatively slow. Such as good quality plastic bottles, loaded into high-grade plastic can be stored for 7-8 months still no reaction; On the contrary, the use of poor quality plastic bottles, even if the better plastic may be in 2-3 months on the deformation.

2. Why is the glue thicker or dry from the bottom cover of the plastic bottle?

This is mainly in the packaging process. Because it takes a certain amount of time from filling to pressing the cover, although the time is short, it also makes the glue contact with the air. If the sealant solidifies a lot from the bottom, it is caused by the sealing of the bottom cover and bottle, and it is the quality control problem of packaging materials.

3. Acid glue extrusion process will be broken or there are small bubbles, why?

There are two main reasons for this.

One is caused by too low storage temperature: if it is sour glue (especially low grade glue) stored at a lower temperature will form a lot of bubbles. The reason may be that after low temperature storage, the liquid raw material changes due to the cold shrinkage volume and forms more bubbles, so it is recommended that the storage temperature should not be lower than 0℃.

Second, formation in the process of canning: in normal canning, there will be a small number of small bubbles in the tail of the supporting glue. If there are more bubbles or broken flow (big bubbles), it is caused by improper operation, which must be improved and should be avoided. However, this situation also has a probability problem, if rare or occasional such phenomenon, should be regarded as accidental events. Large bubbles should be avoided during operation.

4. Why does the surface of acid glue crinkle after curing?

This is mainly in two kinds of base material surface sizing glue layer is too thin caused by, due to the different thermal expansion and contraction rate of different materials, resulting in a large temperature difference, not completely solidified glue will be deformed and wrinkled.

Solution: Apply thick adhesive layer. Generally, the thickness of adhesive layer is about 1mm during construction. It is suggested to increase the thickness to (1.5-2) mm.

5. Why do some sour adhesives discolor aluminum after curing?

Acid glue releases acetic acid when curing, which is corrosive to metal materials. The reason why it can be used on aluminum is that aluminum is protected by an oxide film or coating. So generally speaking, the discoloration of aluminum is not the problem of glue. Here, more should be involved in the construction operation and the quality of aluminum itself. The quality of aluminum mainly refers to the unqualified coating layer of coated aluminum, such as poor adhesion, film layer is too thin and so on will cause the discoloration after sizing; Improper construction will also cause discoloration, if after sizing, aluminum is placed in a poorly ventilated environment, resulting in the release of acetic acid by glass glue curing can not be dispersed in time, local concentration is too high, and the long time of corrosion of aluminum makes it discoloration.