In industrial manufacturing, structural adhesives and sealants are both indispensable and important materials. They all seem to be "glues", but in fact, they are very different in terms of ingredients, characteristics, definitions, and uses. Therefore, I often encounter customers asking me "what is the difference between structural adhesive and sealant", and today I will provide you with easy-to-understand answers based on practical applications.
Difference Between Structural Adhesive and Sealant: The use is the biggest difference.
The encyclopedia explains that gives a very detailed introduction to structural adhesives and sealants. However, in actual procurement, even if these parameters are written in detail on the product manual, it is difficult to quickly distinguish which type of product is more suitable for needs. So, if you are not familiar with the products of the adhesive industry, is there a way to quickly understand the difference between structural adhesive and sealant?
In fact, for non-specialists, the most important thing is to distinguish between the two uses. As you can see from the name, the structural adhesive is mainly for bonding and fixing the "structure", and the sealant is "sealed" for the gaps.
The Difference Between Structural Adhesives and Sealants: Practical Application Examples.
In practical application, structural adhesive mainly replaces traditional connection forms such as welding, riveting, bolting and so on to ensure the firmness of the connection parts, and sealant replaces gaskets, gaskets and other sealing methods to prevent internal gas or liquid leakage outward, and also prevent external dust and moisture from inward incoming.
For the sake of understanding, I would like to give here two examples that I have encountered in my previous work:
1. Structural adhesive, application location: speaker magnet and upper and lower clamps.
The magnet of the speaker is also called a magnet and a permanent magnet. The magnet and the upper and lower clamps need to be bonded with structural adhesive, and after the magnetization is completed, the remanence is the magnetism of the magnet. According to Faraday's law of electromagnetic induction, the greater the magnetic flux, the greater the force of the current moving in the magnetic field, so the magnet also has to withstand a certain force during the operation of the speaker.
If the adhesive doesn't maintain a long-lasting bond, causing the magnet to not function properly, then the speaker can suffer from a variety of problems, such as weak sound, distortion, inaccurate frequency response, reduced power efficiency, and more.
At present, there are three main materials of speaker magnets on the market, namely alnico magnets, ferrite magnets and NdFeB magnets
1) Able to bond a variety of substrates, especially ferrite;
2) High temperature resistance, which can ensure stable bonding under the high temperature generated by the speaker after a long time of operation;
3) Low construction difficulty, fast curing time, simplify the production process.
Based on the customer's needs, we recommended Loctite AA 326 acrylic as a structural adhesive. It is a mix-free, medium-viscosity structural adhesive that is particularly suitable for magnet bonding, cures in just 3 minutes, and is able to withstand temperatures up to 120 °C.
During the construction process, the use of LOCTITT SF 7649 accelerator can cure without the need for oven heating, which not only makes the production process simpler, but also reduces energy consumption, and helps customers achieve comprehensive cost optimization.
2. Sealant, application location: multi-articulated robot arm.
The multi-articulated robot is one of the most widely used robot configurations in the industrial field, also known as the "articulated robotic arm", which is usually arranged to complete painting, automatic assembly, welding and other work. In this type of robot, the joint distribution is designed with reference to the human arm, and the rotation frequency of the large arm is extremely high, so it is necessary to add spacers to the joints. Because the robot category is relatively special, it is not possible to use universal gaskets, so it is necessary to customize gaskets of different shapes and sizes. After the gasket is installed, it will inevitably come loose as the boom swings, eventually losing its seal.
Faced with this situation, the customer approached us and wanted to replace the gasket with a sealant.
In this case, the sealant needed to not only be tight, but also meet the following requirements:
1) It has the characteristics of flexibility, which can cooperate with the swing or extension of the big arm;
2) No damage to the contact surface, avoid corrosion of the surface of the robot arm.
In the end, we selected Loctite 518 Flex Flange Sealant out of dozens of sealants. This sealant is often used to seal between the flange faces of metal machines, allowing direct contact with the metal without affecting it. At the same time, it is also suitable for the work of the robot arm due to its rapid application, solvent resistance, and high pressure resistance.
The difference between structural adhesives and sealants: Loctite offers high-quality products and a full range of services.
For non-professionals, after knowing the "difference between structural adhesive and sealant", it is more important to find the product that best meets their needs. Loctite can provide adhesives for a variety of industries, including but not limited to structural adhesives, sealants, and more. At the same time, each product has a corresponding professional manual, so that non-professionals can quickly familiarize themselves with the product. After entering the formal cooperation, Loctite will also send a professional team for technical support and after-sales service.
After understanding the difference between a structural adhesive and a sealant, choosing the right one is crucial. For enterprises, it is not only necessary to choose the right product, but also to choose the right service. As an adhesive practitioner, we deeply recognize Loctite's high-quality products and comprehensive services, which can bring a variety of advantages and value to customers' enterprises and help them consolidate their core competitiveness.