Adhesives have been used by humans for a long time, so that today they are an inseparable part of various industries. Today, with the growth of technology, polymer adhesives replace other sources of fasteners in various cases. In this article, different types of adhesives are introduced, the amount of adhesive consumption in different industries and in the world is stated, and its applications in different industries are examined .
Adhesive is a material which is used for keeping two surfaces together. Before, use an adhesive surface preparation must be done. For surface preparation, first of all adhesive must wet the surface, then after applying the adhesive on the surface, it must lead to strength between surfaces and remain stable. Most of the times the raw materials which are used for adhesives, are polymeric materials. These polymers can be categorized as below :
• Epoxy resins
• Phenolic resins
• Amine resins
• Silicone resins 
• Poly vinyl acetate
• Poly vinyl acetal
• Poly acrylate
• Cellulose derivatives
• Melt thermoplastic adhesives (Thermal adhesives) 
• Nitryl rubber
• Polysulfides 
• Animal glue 
Applications of adhesives in different industries
Adhesives are extremely used in the most of industries such as: food packing, drug packing, construction, automotive, and medical. As it can be seen in figure1, most of the use of adhesives belongs to packing industry .
As it can be seen in the figure 5 to link different parts such as: roof, windshield and, side panels are sued adhesives.
Nowadays, in transportation industry especially in marine transportation is adhesives are widely used because, in marine industry the low weight of products and improving the quality of products is crucial. In figure 6 and 7 use of different adhesives in the ships and aircrafts has shown.
It can be used for:
• Gluing ceramics and tiles
• Gluing flooring
• Gluing prefabricated and concrete roofs
There are adhesives that are cured and hardened by drying. These adhesives are classified into two categories: water-based and solvent-based, which are called emulsion adhesives.
Solvent-based adhesives are divided into two categories:
1- Wet bonding adhesives
2- Contact adhesives
Water-based adhesives are adhesives that use water as an active component, and the connection is made by water evaporation or water absorption by the base material. Water-based adhesives, like solvent-based adhesives, are divided into two categories: contact and wet bonding. It is expected that water-based adhesives will replace solvent-based adhesives in the last decade.
Pressure-sensitive adhesive is an adhesive that adherence the adhesive with the substrate by applying a small amount of pressure. Pressure-sensitive adhesives can be solvent-based, water-based, or hot-melt.These adhesives have a widely range of applications from automotive and medicine industry to basic industries.
Adhesives that are cured with UV rays, this curing method requires less time than the thermal method and reduces the side products, so that UV adhesives have replaced thermal adhesives in most fields. UV adhesives are used for medical purposes such as making syringes, tweezers, and dental fillers. These adhesives are also used in the wood industry, making decorations, and other industries.Some adhesive manufacturers world-renowned companies:
Author: Emad Izadi Vasafi
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 Gadhave, Ravindra Vilas Indubai, and Chaitali Ravindra Gadhave. “Adhesives for the Paper Packaging Industry: An Overview.” Open Journal of Polymer Chemistry 12.2 (2022): 55-79.
 Sanai, Yasuyuki, and Kouzou Kubota. “Effect of UV-curing conditions on the polymer structures: A comparison between coating and adhesive.” Polymer Journal 52.9 (2020): 1153-1163.