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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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