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The substance that makes two things stick together is known as adhesives. Cement, mucilage, glue, and paste are common adhesives.
Adhesives
Characteristic of adhesives:
The adhesion (attraction between different molecules) and cohesion (attraction between the same molecules) are the properties of adhesives, making two substances stick together.
Types of adhesives:
There are two types of adhesives based on the source of materials. They are natural and artificial adhesives.
Natural adhesives:
They are made from naturally occurring materials such as plants, animals and minerals. Starch, beeswax and dextrin are natural adhesives extracted from corn, rice, potato or wheat.
Artificial adhesives:
Artificial adhesives are made synthetically in industries and mostly of polymers. They are costly when compared to natural adhesives. The polymers used in artificial adhesives are primarily of resins and rubbers. Polyurethanes, epoxies, and cyanoacrylates are examples of synthetic adhesives.
Uses of adhesives:
- It is used in construction industries for the adhesion of ceramic tiles, laying of carpets and sticking of pipes.
- It is also used in fabric industries for a variety of applications including textile finishing, tailoring, technical fabrics, and more.
- It is used in carpentry to assemble the furniture parts.
- It is used in ceramic and leather industries for assembling the finals products.
- It is used in paint industries, for decorative purposes, in photography, in plywood etc.
Example:
Flat tyre
We have seen a flat tyre being repaired by a shopkeeper. First, he will find the area to be punctured by
immersing the tube in water.
immersing the tube in water.
The bubbles in water indicate the hole in the tube, and then it is roughened. The tube is dried, and adhesive is applied both on the roughened surface and the patch that is covering the tube.
Finally, the pressure is applied on both the surfaces after sticking to increase the adhesive capacity and to ensure the binding takes place.
Reference:
<a href="https://www.vecteezy.com/free-vector/adhesive">Adhesive Vectors by Vecteezy</a>
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