Adhesives.

Adhesives

Any substance that is capable of holding materials together by surface attachment that resists separation is called adhesives.
Cement, mucilage, glue and paste are interchangeable terms used for any organic substances that forms an adhesive bond.
The stickiness of adhesives is caused by molecular bonds and its strength depends on how much stress is needed to pull those bonds apart.
When the glue dries over a surface, it hardens, causing the molecule to stick together. On the other hand tape is made from mixing rubbery material with adhesives.

Adhesives.
Natural adhesives are made from organic sources such as vegetable starch, natural resins, or animals.
They are often reffered to as bioadhesives.
Synthetic adhesives are based on elastomers, thermoplastics and thermosets.
Examples of thermosetting adhesives are epoxy, polyurethane, cyanoacrylate and acrylic polymers.
Adhesives can contain hazardous solvents, plastics and preservatives. Many adhesives contain solvent that are toxic by inhalation and skin contact.
Besides their role in the adhesion process, they can be used for other purpose such as sealing agents to prevent oxidation and corrosion, waterproofing etc. NEXT

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Polymers

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