为什么胶水不会被粘在瓶子里？
很多人都遇到过这样的情况，使用胶水忘记封口，几天后发现就已经凝固无法使用了。胶水本身是由粘合剂和水组成，想要胶水粘得牢，有两个重要条件。第一个是物体间的胶水充分接触，第二是胶水中的水分（挥发剂）全部挥发。当胶水与空气接触，会发生聚合反应，导致水分挥发，所以会凝固得很快。
正常情况下胶水被装在封闭的瓶子里，因此其中不存在聚合反应所需的条件，也就不会被粘在胶水瓶里。另外根据胶水的活性，一般胶水瓶的材料也会选用惰性材料，因此也更加稳定和安全。
Knowledge Post | Why doesn't glue stick to the inside of the glue bottle?
Glue, as a common adhesive tool in our daily lives, often bonds various materials very firmly. But have you ever wondered why glue can stick to almost anything but doesn't stick inside the glue bottle?
The Development of Glue
When it comes to the development of adhesives, it actually has a history of several thousand years. The paste we commonly use for sticking couplets during the Chinese New Year is actually the most widely used glue in ancient times. However, the adhesiveness of paste is limited, so people discovered that substances extracted from plants or animals could also be used to make adhesives, such as resin from pine trees, and fish glue made from fish bladders, etc., for bonding furniture or sealing joints.
Later, with the emergence of polymer materials, synthetic glue was developed. This type of glue has higher strength and a wider range of applications, gradually becoming an indispensable product in our daily lives and production work.
Why Doesn't Glue Stick to the Bottle?
Many people have encountered the situation where they forget to seal the glue, and a few days later, they find it has already solidified and become unusable. Glue itself is composed of adhesive and water. There are two important conditions for glue to stick firmly: firstly, there must be sufficient contact between the adhesive and the objects being bonded, and secondly, all the moisture (volatile solvents) in the glue must evaporate. When glue comes into contact with air, a polymerization reaction occurs, leading to the evaporation of moisture, causing it to solidify quickly.
Under normal circumstances, glue is stored in a sealed bottle, so the conditions required for polymerization reactions are not present inside the bottle, thus it doesn't stick to the inside of the glue bottle. Additionally, depending on the activity of the glue, the materials used for glue bottles are generally inert, making them more stable and safe.返回搜狐，查看更多