DU
Open a cartridge of acetic cure silicone and you will notice the sharp vinegar smell. That smell is the chemistry telling you what the sealant releases as it cures — and it is the key to choosing between the two cure systems. Here is how our team explains the difference to distributors and contractors.
What Happens During Cure
Both types are room-temperature vulcanising (RTV) silicones that react with moisture in the air. The difference is the byproduct:
- Acetic cure releases acetic acid while curing — the vinegar smell. Cure is fast and reliable in humid conditions.
- Neutral cure releases alcohol or oxime compounds, which are nearly odourless and non-corrosive to most building materials.
Where Acetic Cure Is the Wrong Choice
Acetic acid is mildly corrosive. Avoid acetic cure sealants in contact with:
- Corrosion-sensitive metals such as copper, brass, lead and galvanised steel
- Concrete, mortar and other alkaline substrates
- Electronic components and electrical housings
- Photovoltaic modules and other encapsulated assemblies
- Reflective or fritted glass edge coatings on sensitive projects
In these applications, a neutral cure grade is not a preference — it is a requirement.
Where Acetic Cure Still Performs Well
Acetic cure silicones remain popular for general glazing, glass-to-glass joints, sanitary sealing and household applications. They bond well to glass and glazed surfaces, skin over quickly, and are typically more economical. For a general-purpose acetic grade, DUDI 6600 multi-purpose silicone is our workhorse for these scenarios.
Quick Selection Table
| Application | Recommended Cure | Why |
|---|---|---|
| Curtain wall structural glazing | Neutral | Non-corrosive to coatings and frames; certified structural grades are neutral |
| Metal, concrete and stone joints | Neutral | Acetic acid attacks sensitive metals and alkaline surfaces |
| Photovoltaic modules | Neutral | Cell and junction corrosion risk with acetic byproducts |
| General glass glazing | Either | Acetic bonds glass well and is economical |
| Sanitary and household sealing | Acetic or neutral | Acetic skins fast; neutral where odour matters |
The Bottom Line
If the joint touches sensitive metals, concrete, electronics or anything living under a 25-year warranty, specify neutral cure. For everyday glass work where cost matters, acetic cure is still a sound choice. DUDI manufactures both systems — from DUDI 6600 acetic general purpose to DUDI 9000 and DUDI 7000 neutral structural and weather grades — so your specification logic, not your supplier's inventory, drives the choice.