Applications of Contact Adhesives
Contact Adhesives. I'm sure all woodworkers have come across either liquid nails or powder contact adhesives. They've either heard about them from a friend, family member, or read about them on the internet, and may still be wondering just exactly what contact adhesives are. Contact adhesives come in two varieties, solvent-based contact adhesives and water-based contact adhesives. Both use similar techniques to attach materials to wood, however, each type has some distinct properties that make them more appropriate for certain applications than the other.
Solvent-based adhesives allow bonding materials like veneer, gypsum, laminate, and MDF to be readily and permanently bonded to wood surfaces without the use of water. Water-based adhesives allow for more flexibility in working with irregular or very smooth surfaces, or when the materials need to be bonded to curved surfaces. Solvent based adhesives also tend to dry faster than water-based ones, and also tend to leave a cleaner, more uniform finish.
The primary difference between solvent and water-based adhesives lies in their chemical makeup. Solvent based adhesives contain ethanol, methanol, or isopropyl alcohol, while water-based adhesives contain ethyl alcohol or isopropyl alcohol. Ethanol is the preferred ingredient because of its relative strength, which allows a greater amount of force to be exerted when using adhesive glue, and more consistent results when drying. Methanol is also a known inhibitor of bacterial growth. When using ethyl alcohol as a solvent, however, care should be taken that you don't have any surface contamination when applying the glue, because it will form an easy way for bacteria to form under the glue's surface.
Another difference between these two types of contact adhesives lies in their method of application. Water-based adhesives can be applied directly to a surface by spraying it into a can or pump bottle. They are widely used for applications that involve application to rubber and plastic parts, like patches, caps, handrails, and straps. To create these products, a solution of ethyl alcohol and water is combined in a mixing container. Once combined, the mixture is poured into molds, which are specially designed to create the different shapes and forms desired by various industries.
Solvent-based adhesives have a significantly shorter drying time. Most commonly used for cosmetic and artistic applications, these products are also useful for drying hard materials like wood and metal. They usually dry quickly and without drip or staining. Depending on the specific application needs, solvents may even be incorporated into the bonding agent for faster drying time and reduced clean-up times. In terms of cleaning, solvent evaporation is often preferred over water because it leaves fewer contaminants on the product surface.
A common application of contact adhesives is for bonding rubber parts together. These products are mostly used when a strong adhesive must be used for high-quality industrial parts that cannot be glued on using other techniques. For example, car parts that have to be glued onto a frame or other structure would require the use of strong adhesives in order to ensure that the parts stay in place. Other applications include repairing metallic surfaces that have been subjected to exposure to corrosion, repairing and replacing sensitive plastic parts, and constructing or fabricating clothing or garments with rubber fibers. In all cases, using appropriate contact adhesives makes it easier for manufacturers or designers to produce high-quality products.
Contact adhesives based on volatile organic compounds (VOCs) provide stronger bond strengths than regular adhesives. The reason for this is that these additives give the materials an organic, waxy or tacky feel when they have been mixed with water. This property gives the materials an ability to repel oil and grease, making them ideal for bonding plastic parts. They also have the ability to increase the tackiness of rubber parts while reducing the amount of friction that can result from repeated contact with oil or grease. While they have lower adhesion properties than other forms of contact adhesive, VOC-based adhesives offer excellent resistance to ozone.
There are many other uses for contact adhesives besides bonding. They have the ability to fill in tiny depressions on flat surfaces, or to fill in scratches from bumping into something solid. This provides additional strength to objects that would otherwise be difficult or impossible to handle. Since contact adhesives have the ability to mold, form and bond, they offer designers and manufacturers a way to enhance the design characteristics of their products. contact spray adhesive