Glass fiber wetting agent: a bridge between technology and materials science

In the composite materials industry, glass fiber is a reinforcing material. The optimization of its performance and the expansion of its application range cannot be separated from a key auxiliary agent-glass fiber wetting agent.

1. The basic concept of glass fiber wetting agent

Glass fiber wetting agent, also known as penetrant, is a surface-active substance. It can significantly reduce the surface tension of the sizing system, making it easier for the sizing agent to wet the surface of the glass fiber and achieve the effect of uniformly impregnating the original fiber. The application of wetting agent in glass fiber production is not only related to the quality control of the product, but also directly affects the mechanical properties, weather resistance and processing properties of the final composite material.

2. The main role of glass fiber wetting agent

Fiber adhesion and bundling:

During the glass fiber drawing process, the wetting agent can prevent the fibers in the original fiber from being scattered, and adhere to each other to form a stable fiber bundle. This helps to maintain the integrity of the fiber, avoid stress concentration on a single fiber, and reduce the phenomenon of scattered and broken fibers.

Lubrication and protection: The lubricating component in the wetting agent provides lubrication between the glass fiber and the equipment such as the oiler, the clustering trough and the cable arranger, reduces friction, and avoids problems such as flying wire and fuzzing of the bundle caused by excessive tension. At the same time, it can also protect the fiber surface from mechanical damage.

Eliminate static electricity: Glass fiber is prone to accumulate static electricity during the production process, resulting in mutual adhesion between fibers, affecting the smooth progress of the drawing and weaving processes. The antistatic agent in the wetting agent can reduce the surface resistance of the fiber, form a conductive channel, and effectively eliminate static electricity.

Improve wettability: The wetting agent can improve the wettability of the resin on the surface of the glass fiber coated with the wetting agent, promote the penetration of the resin into the fiber monofilaments, and enhance the bonding force between the fiber and the resin, thereby improving the mechanical properties of the composite material.

Provide processing characteristics: The wetting agent can also give the glass fiber processing characteristics such as choppability, ribbonization, and dispersion, so that it can quickly infiltrate in substrates such as thermosetting or thermoplastic resins, rubber, gypsum, cement, etc., broadening the application range of glass fiber.

3. Types of glass fiber wetting agents

Glass fiber wetting agents can be divided into many types according to their composition and performance:

Textile wetting agents:

Such as paraffin emulsion, the main ingredients are paraffin, vaseline, stearic acid and other mineral lipids. This type of wetting agent is beneficial to textile processing, but it will hinder the resin from wetting the glass cloth and affect the combination of resin and fiber, so it needs to be removed before dipping.

Enhanced wetting agent:

The main ingredients include film-forming agents (such as water-soluble resins, resin emulsions, etc.), coupling agents, lubricants, antistatic agents, etc. This type of wetting agent has little effect on the performance of FRP and does not need to be removed before dipping. It is suitable for the production of untwisted roving, untwisted roving fabrics, chopped fibers and chopped fiber mats.

Special wetting agents:

Such as 711 wetting agent suitable for polyester resin, 4114 wetting agent suitable for phenolic and epoxy resins, etc. This type of wetting agent is designed for specific resin systems and can better meet the performance requirements of composite materials.

Silicone, phosphate and fatty acid salt wetting agents: These wetting agents are widely used in glass fiber production due to their excellent high temperature resistance, good dispersibility and stability, and low cost.

4. Application examples of glass fiber wetting agents

Take magnesium aluminum silicate fiber with a diameter of 9 microns as an example. After being treated with anhydrous reinforcing wetting agent "HTS", its tensile strength can reach 4900MPa, elastic modulus is 9×10^4MPa, and heat resistance is significantly improved. This fully demonstrates the great potential of wetting agents in improving the performance of glass fibers.

5. Conclusion

As an important auxiliary agent in the composite material industry, the application of glass fiber wetting agents in glass fiber production is not only related to product quality control and performance optimization, but also directly affects the mechanical properties and processing properties of the final composite material. With the continuous advancement of science and technology and the growing demand for high-performance composite materials, the research and application of glass fiber wetting agents will be more in-depth and extensive.