Collection: Silicone Sealant

A silicone sealant stays flexible over a temperature range that neither polyurethane nor hybrid can reach, and it resists UV without yellowing or cracking. These are its two specific qualities, and they explain why it is used despite its constraints.

The reference in the catalogue

Dagobert Industrie stocks SIKA Sikasil SG-500 silicone sealant, designed for structural glazing. See also our adhesive sealants, our hybrid sealants and our polyurethane sealants.

Neutral or acetoxy, a difference that damages parts

This is the most important and least known point.

An acetoxy silicone releases acetic acid as it cures, hence its vinegar smell. It adheres well to glass and non-porous surfaces, but this acid attacks metals, notably copper, brass, zinc and some steels, and it can break down concrete and limestone.

A neutral cure silicone releases no acid. It is compatible with metals, stone and most sensitive substrates. It is the only one usable in contact with a metal structure.

Using an acetoxy on an aluminium frame or near copper causes corrosion that appears months later, when the joint is already in place.

Structural glazing is not sealing

A structural glazing silicone like SG-500 is not a sealing joint: it transmits loads. It is what holds the glass on its frame, and its sizing, bead width and thickness, comes from a calculation, not from habit.

This type of product falls under controlled application. It cannot be improvised from a tube of bathroom silicone.

The limit to remember

Nothing adheres to silicone, not paint, not adhesive, not even another silicone after ageing. Worse, silicone migrates: a trace on a neighbouring surface is enough to prevent any later adhesion there, and ordinary cleaning does not remove it.

On a part intended to be painted or reworked, choose something else, or apply silicone as the very last operation.