Adhesives are used everywhere, from automobiles, to computers, to construction sites. But what are polymer adhesives and what makes them so useful?
In this article you will learn what makes a "polymer adhesive" different from other types of adhesives. You'll learn some of the various types of adhesives and their different capabilities. You'll also learn that often times adhesives are used for more than just bonding components and substrates.
Other resources worth checking out:
- Comparing Lap Shear Strengths Of Polymer Adhesives
- Viscosity Of Specialty Adhesives
- 3 Types Of Thermal Transfer Products
How are polymer adhesives different than regular adhesives?
They aren't really different... Polymer adhesives are simply a category within the larger group of adhesives. A polymer substance is formed when a large number of similar small molecules react together to form a much larger molecule. So a polymer adhesive is simply an adhesive that cures or sets in this method, through a chemical reaction that involves small molecules reacting and connecting together.
For example, a two-part epoxy adhesive starts as two liquid materials, generally referred to as the resin and hardener components. However, when you combine and mix these two liquids together they undergo a chemical reaction. This reaction involves the molecules of the resin side connecting with the molecules of the hardener side. As long as the resin and hardener sides are combined in the correct ratio they will continue to react until they have formed a solid polymer substance. The resulting solid substance works to hold the adherends in place, creating an adhesive bond.
A negative example would be a pressure sensitive adhesive, such as tape. Pressure sensitive adhesives don't rely on polymerization in order to develop the adhesive bond. Instead pressure sensitives bond to substrates by wetting out the sticky material along the substrate. Once the sticky material has wet out, the adhesive bond is established. No polymerization necessary.
What are the different types of polymer products?
There are many types of polymer adhesives of various base chemistries and different physical and chemical properties. To name a few examples:
- Epoxy: Epoxies generally form strong and rigid polymers. Epoxy products can be filled with silver or other metals to provide electrical conductivity between bonded components.
- Polyurethane: Polyurethanes tend to form tough and flexible polymers. Polyurethane adhesives are occasionally used to encapsulate sensitive electronic equipment, primarily providing protection rather than an adhesive bond (adhesives aren't always used to adhere, believe it or not).
- UV Acrylates: UV bonding acrylates are particularly interesting because the polymerization reaction can be initiated by UV radiation. Simply expose the liquid system to UV light and watch the adhesive quickly cure.