The application of liquid Rubber in Automotive Welding and assembly adhesives

With the development of the automotive industry, people's pursuit is no longer limited to the level of transportation tools, but more focuses on their driving performance. The comfort of the vehicle is mainly reflected in its excellent sealing and waterproofing, shock absorption and noise reduction, as well as NVH performance. To ensure the performance requirements，such as sealing, shock absorption, noise reduction and the comfort of the whole vehicle, the vehicle should be coated.

Vehicle adhesives are divided into welding adhesives and painting adhesives. Among them, there are mainly six types used in the welding workshop: spot welding sealant, expansion and shock absorption adhesive, edge folding adhesive, structural adhesive and reinforcing film.

The application of liquid Rubber in Automotive Welding and assembly adhesives

With the development of the automotive industry, people's pursuit is no longer limited to the level of transportation tools, but more focuses on their driving performance. The comfort of the vehicle is mainly reflected in its excellent sealing and waterproofing, shock absorption and noise reduction, as well as NVH performance. To ensure the performance requirements，such as sealing, shock absorption, noise reduction and the comfort of the whole vehicle, the vehicle should be coated.

Vehicle adhesives are divided into welding adhesives and painting adhesives. Among them, there are mainly six types used in the welding workshop: spot welding sealant, expansion and shock absorption adhesive, edge folding adhesive, structural adhesive and reinforcing film.

Expansion shock-absorbing adhesive is often used for shock-absorbing bonding of exterior body panels, engine hoods, side panels, trunk lids, roof lids, inner and outer door panels, etc. Its main function is to enhance the NVH performance of vehicles and increase driving comfort.

Edge folding adhesive is mainly used for edge wrapping of outer panels such as the doors, engine hoods and trunk lids. It increases the connection force between the edge wrapping and the connecting sheet metal, enhances the overall rigidity, and has functions such as waterproofing, dustproofing, rust prevention and preventing dust from entering the joint area.

Structural adhesives are mainly used for sealing connections between outer panel parts and outer panel reinforcing parts. When high bonding strength is required and there are no weld points or poor weldability on the outer panel surface, adhesives can be used instead of welding to avoid pits on the vehicle body surface caused by welding and enhance the aesthetic appeal of the vehicle body.

Reinforcing film can be firmly adhered to the inner layer of the outer panel, thereby strengthening the car body frame, reinforcing the car body structure and improving the stability of the car body.

High-performance automotive spot welding sealants and expansion shock-absorbing adhesives are mainly composed of solid synthetic rubber, liquid polybutadiene rubber, rubber vulcanizing agents, fillers, etc. They feature excellent oil surface adhesion, sealing performance, elasticity, vibration resistance and aging resistance. High-performance automotive edge folding adhesives, structural adhesives and reinforcing films are mainly composed of epoxy resins, toughening agents, curing agents, fillers, etc. Among them, toughening agents include liquid polybutadiene rubber, liquid nitrile rubber, etc.

The Polyvest series of liquid polybutadiene produced by Evonik is widely used in the field of automotive welding and assembly rubber due to its unique chemical structure and properties, mainly reflected in the following advantages:

• 1.Chemical stability: It has excellent water resistance, acid and alkali resistance, can prevent rust and corrosion, and does not react with the pretreatment solution and electrophoresis solution for automotive painting.
• 2.Low-temperature flexibility: With a low glass transition temperature, it features elasticity and low-temperature flexibility, providing excellent construction results at low temperatures, good sealing performance, and superior shock absorption.
• 3.Substrate adhesion: It has good adhesion to metal substrates, especially excellent oil surface workability and adhesion to oil surface steel plates.
• 4.High vulcanization reactivity: The molecular chain contains unsaturated double bonds and can be rapidly cross-linked through sulfur vulcanization or peroxides to form a dense network structure.
• 5.Low viscosity: Good fluidity, easier to mix evenly with other components, improving processing performance.

Shanghai Sifeng is the official authorized agent of Evonik's Polyvest series products. Relying on the local warehousing and logistics network, it provides efficient and stable product supply. By integrating Evonik's product R&D and application technology resources, it converts the technological advantages of Evonik's Polyvest series products into the actual productivity of the client side. Promote the popularization and innovative application of high-performance welding and assembly adhesives in China's automotive industry chain.