Zinc Stannate (ZS) is a high-performance, inorganic smoke suppressant and flame retardant synergist, primarily used in halogen-containing systems. It is a key replacement for Antimony Trioxide (ATO).

Flame Retardant Mechanism ZS functions almost entirely in the condensed phase (solid-state):

1. Condensed Phase Action: In halogenated polymers like PVC, ZS acts as a Lewis acid and catalyst. It intercepts the HCl released during decomposition and promotes cross-linking of the polymer chains.

2. Char Promotion & Smoke Reduction: This cross-linking action builds a stable, non-volatile char layer instead of allowing the polymer to “unzip” into flammable, smoky, aromatic compounds. By trapping the fuel in the solid phase, it dramatically reduces smoke generation.

Key Application Areas

• Flexible PVC: Its primary application is in flexible PVC where stringent smoke emission standards are required.

• Plenum-Grade Cable: A key additive for plenum-rated wire and cable jacketing (e.g., UL 910) to minimize smoke in case of a fire.

• Wall Coverings & Flooring: Used in PVC-based wall coverings, flooring, and other building materials.