Zinc Borate 3.5 Hydrate

Zinc Borate 3.5 Hydrate contains 3.5 molecules of water of crystallization and is a highly effective flame retardant that also suppresses smoke and resists electric arcs. It can be used in a variety of polymer systems, including PVC, nylon, epoxy resin, polyethylene, PP, PE, thermoplastic elastomers, and rubber.

Flame Retardant Principle

In the initial stage of heating, Zinc Borate 3.5 Hydrate preferentially decomposes and releases water of crystallization. From a flame retardant perspective, this process is strongly endothermic; heat from the material surface is rapidly carried away, and surrounding combustible gases are diluted by water vapor, hindering the heating and combustion process.

Subsequently, boron in the material participates in the reaction, allowing the polymer to form a denser and more stable char layer, reducing oxygen entry and preventing heat transfer to the material's interior. After decomposition, zinc forms a glassy protective film on the material surface, further strengthening the char layer and inhibiting molten dripping. Therefore, zinc borate plays a stabilizing role in the combustion stage, both in the early and later stages of flame retardancy.

Application Field

1. Polymer materials industry

Engineering plastics field (electronic appliances, automotive parts, building materials, home appliance casings)

Rubber field (conveyor belt system, sealing products, cable sheath)

Special application fields (aerospace, shipbuilding, military equipment)

2. Coatings and adhesives industry (fireproof coatings field, flame-retardant adhesives field)

3. Building materials and insulation materials industry (artificial board field, insulation materials field)

Physical and Chemical Properties