Acrylic adhesive is a fast-bonding, highly resistant epoxy made by polymerizing acrylic or methacrylic acids through a reaction with a catalyst. They require no mixing and are in a 2-component form, which means the acrylic is applied to one surface and the catalyst, hardener or accelerator is coated to the opposite surface. When those surfaces are pushed together, the two adhesive components bond together and form a water tight seal.
The double component acrylic adhesive will bond to almost any material, including wood, plastic, most metals, ceramic, rubber, glass and even oily surfaces. The bonding happens fast at room temperature and is highly resistant to chemicals, environmental conditions and moisture. Acrylic is an adhesive often used in the construction industry to bond two surfaces together much like epoxy is most often employed by engineers. They are also used in medical applications to bond implants to bone.
When coated on foam or paper, acrylic adhesives replace fasteners in appliance, automotive, sign and graphics applications. They also provide sound and vibration dampening and adhere decorative film and over-lamination to surfaces. Some food grade acrylic adhesives are used in food processing to seal packaging. Adhesive made from acrylic have different viscosities, meaning different resistances to flow. Those that are liquid form come in spray bottles, while the thicker adhesives are contained in tubes.
The curing process, which is what initiates the adhesive harden, is prepared by an adhesive manufacturer. The process is dependent upon the room temperature. Curing refers to the length of time required to fully set a bond between the adhesive and surface material. The lower the temperature, the longer the curing time will take. If the temperature is too low, acrylic adhesives tend to get brittle, although they will still last for many years.
They always exhibit good peel and shear strengths as well as shock and impact resistance. Acrylic also withstands thermal movement and maintains its bond when exposed to water. When used during an industrial manufacturing process, acrylic is a cost effective method of adhesion because it does not require heat in order to cure, which eliminates the need for an expensive heating system.
Unlike the easily removed pressure sensitive adhesives, acrylic adhesives are to be used only for permanent adhesion. Once it has cured, removal is difficult, time consuming and often results in a damaged surface. However, the bond is permanent and strong, and can be used in applications like cabinet building, where the bond must stay for decades.