Application of coupling agents

Application of coupling agents

Coupling agent is a kind of organic compound with special structure, which plays an important role in the field of material science. It can tightly combine two materials with different properties through chemical reaction or physical action, which can significantly improve the performance of materials.It has a wide range of applications:

1.Plastic Industry

Filler modification: Adding inorganic fillers (such as calcium carbonate, talc, etc.) to plastics can reduce costs and improve hardness and other properties, but inorganic fillers are poorly compatible with organic polymers. Coupling agent can form a chemical bond on the surface of the filler, and the other end interacts with the polymer molecular chain to improve compatibility. For example, in polypropylene by adding silane coupling agent treatment of talcum powder, can make the tensile strength of composite materials, impact strength increased significantly.

Toughening: When used in glass fibre reinforced plastics, the coupling agent can improve the interfacial bonding between the glass fibre and the resin. Such as the use of glass fibre reinforcement in unsaturated polyester resin, glass fibre treatment through silane coupling agent can enhance the mechanical properties of the composite material, so that it is widely used in automotive parts, aerospace and other fields.

2.Rubber Industry

Improve the combination of filler and rubber: Fillers such as carbon black and silica are often added to rubber products to improve strength, abrasion resistance and so on. Silica surface contains a large number of hydroxyl groups, and non-polar rubber compatibility, the use of silane coupling agent treatment of silica, can enhance its interaction with rubber. For example, in the manufacture of tyres, the use of silane coupling agent treated silica filled with rubber can reduce the rolling resistance of tyres, improve wet slip resistance and wear resistance.

Improve the processing performance of rubber: coupling agent can make the filler dispersed more evenly in the rubber, reduce the viscosity of the rubber material, improve the mixing process, improve production efficiency. For example, in the rubber mixing process, adding appropriate amount of coupling agent can make the filler quickly and evenly dispersed, reduce mixing time and energy consumption.

3.Coating Industry

Improve coating adhesion: When coated on the surface of metal, wood and other substrates, the coupling agent can react with the hydroxyl and carboxyl groups on the surface of the substrate, and at the other end, interact with the film-forming substances in the coating to form a chemical bond or physical entanglement and enhance the adhesion between the coating and the substrate. For example, in metal anti-corrosion coatings, the use of titanate coupling agent pretreatment of the metal surface can significantly improve the adhesion of the coating to the metal and corrosion resistance.

Improve the weathering and chemical resistance of the coating: by enhancing the bonding force between the coating and the substrate, the coupling agent can effectively prevent the penetration of moisture, oxygen and other corrosive media, and improve the weathering and chemical resistance of the coating. For example, the application of coupling agent in building exterior coatings can make the coating withstand the wind, sun, rain and other natural environment erosion for a long time, maintaining good decorative and protective properties.

4.Adhesive industry

Enhance bonding strength: Between the adhesive and the bonded material, the coupling agent acts as a bridge to improve the bonding force between the two. For example, in structural adhesives, the use of silane coupling agent treatment of the surface of the material to be adhered to, can significantly improve the adhesive strength of the adhesive to metal, ceramics and other materials, so that the bonded joints can withstand greater loads.

Broaden the scope of application of adhesives: can improve the adhesive bonding properties of adhesives to different materials, expanding its scope of application. For example, some of the original bonding effect of some difficult to stick to certain materials (such as polyolefin plastics) is not good adhesive, after adding the appropriate coupling agent, can achieve effective bonding of these materials.

5.Other applications

In magnetic materials: it can improve the bonding force between magnetic powder and binder, improve the magnetic properties and mechanical properties of magnetic materials, so that magnetic materials are widely used in electronic devices and other fields.

In FRP industry: coupling agent can enhance the interfacial bonding between glass fibre and resin matrix, and improve the strength, water resistance and other properties of FRP products, which are used in the manufacture of cooling towers, chemical pipes and other products.