Industrial adhesives are organic and inorganic chemical compounds that are used to join components. Products include acrylic, epoxy, hot melt, polyurethane, silicone, thermoset, and UV curing adhesives, as well as industrial sealants. Most industrial adhesives are used in fastening applications. Industrial sealants are used to fill gaps between seams, or on surfaces; and to contain fluids, prevent leaks, and prevent the infiltration of unwanted material.

Types of Industrial Adhesives

Industrial adhesives can be categorized in a number of different ways, but typically by chemical composition (as in acrylic adhesives) or by adhesion properties (e.g., hot melt adhesives).

Chemical Composition

The types of industrial adhesives and sealants found in the Engineering360 SpecSearch database include acrylics and cyanoacrylates; epoxy adhesives; phenolic, melamine and urea formaldehyde resins; and polyurethane adhesives. Rubber and silicone products are also available from many different suppliers.

Acrylic adhesives are known for their excellent environmental resistance and fast-setting times when compared to other resin systems. Cyanoacrylates, or super-glues, are one-part acrylate adhesives that cure instantly on contact with mated surfaces through a reaction with surface moisture.

Epoxy adhesives are chemical compounds for joining components. A copolymer, epoxy is formed from two different chemicals: a resin and a hardener.

Phenolic, melamine, and formaldehyde resins are thermosetting adhesives that form strong bonds and have good resistance to high temperatures. As thermoset materials, they require heat or heat and pressure to cure and to form a secure bond.

Polyurethane adhesives provide excellent flexibility, impact resistance, and durability. They are often used in finish carpentry and with woodworking projects.

Rubber adhesives and sealants provide highly flexible bonds and are usually based on butadiene-styrene, butyl, polyisobutylene, or nitrile compounds.

Silicone adhesives and sealants have a high degree of flexibility and very high temperature resistance. They are used in plumbing as well as in marine applications.

Adhesion Properties

Industrial adhesives that are defined by their adhesion properties include hot melt, pressure sensitive and contact, thermoset, and UV curing adhesives (radiation and light curable).

Hot melt adhesives can be repeatably softened or melted by heat and hardened or set by cooling. They allow parts to be removed or repositioned during assembly.

Pressure sensitive adhesives (PSA) and contact adhesives adhere to most surfaces with very slight pressure. Contact adhesives are well-suited for applications with large surface areas, or where clamping is difficult.

Thermoset adhesives are crosslinked polymeric resins cured using heat, or heat and pressure. They exhibit good creep resistance and are used for high load assemblies.

UV curing adhesives and radiation curable adhesives use ultraviolet (UV) light or other radiation sources to initiate curing, which allows a permanent bond without heating.

Specifications

The primary selection specifications for most engineering users are substrate type or material compatibility, use temperature and break strength. The following chart summarizes these parameters for a selection of suppliers in Engineering360’s SpecSearch database.

For most engineering users, the primary numeric specification for industrial adhesives is use temperature. The following chart summarizes this parameter for a selection of suppliers in Engineering360’s SpecSearch database.

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Pittsburgh Corning