Reject "scumbag" projects, 5 tips to identify inferior "white oil sealant"

Silicone sealant is resistant to high and low temperatures, aging, and UV rays. It has good bonding properties. The waterproof sealing layer formed after curing has both elasticity and bonding properties. It has always been widely favored in the construction industry.

Due to the fluctuation in the market price of dimethyl silicone oil, some manufacturers use cheap white oil to replace the dimethyl silicone oil required in sealant production in order to reduce costs, which has brought safety risks to doors, windows and curtain walls.

1. What is “white oil”?

White oil, commonly known as paraffin oil and mineral oil, is a mixture of n-isoparaffins extracted from crude oil. It is flammable and volatile.

Under normal circumstances, silicone sealants use dimethyl silicone oil as a plasticizer to achieve good elasticity. In order to reduce costs, some manufacturers use white oil instead of dimethyl silicone as a plasticizer to increase the gloss and extrusion speed of the sealant.

However, white oil has a smaller molecular weight, lower viscosity, and particularly strong permeability. Silicone sealants using white oil as plasticizer often cause various problems.

2. What are the dangers of “white oil sealant”?

Cause sealant to age and crack in advance

Over time, the tensile strength of the sealant containing white oil gradually decreases and the hardness gradually increases, and the sealant will become hard and brittle. There are phenomena such as early failure of insulating glass and leakage of doors, windows and curtain walls.

Causes insulated glass to "cry"

In strong sunlight or high temperature environments, white oil will evaporate from the silicone sealant, affecting the aesthetics of the building and making the glass sealing worse.

3. How to distinguish "white oil sealant"?

(1) "Thin film method"

Take a slightly thick piece of polyethylene plastic film, apply silicone sealant on the film, and scrape it flat. Wait for a while and then open it. If the film becomes uneven, the sealant contains white oil.

(2) Look at the appearance

The brighter the colloid, the more white oil is added.

(3) Listen to the price

Be especially wary of silicone sealants priced below the market price.

(4) "Butyl sealant" contact method

White oil can dissolve butyl sealant. Take butyl sealant and put it into silicone-based paste. If the butyl sealant dissolves, the sealant contains white oil.

(5) Instrumental analysis method

GB/T 31851-2015 "Detection Method for Alkane Plasticizers in Silicone Structural Sealants" provides thermogravimetric analysis and infrared spectroscopy analysis methods, which can be compared and analyzed if conditions permit.

4 Conclusion

White sealant not only destroys the beauty of the building and reduces the service life of the silicone sealant, but more seriously endangers the safety of doors and windows, causing unnecessary losses and trouble to the owners. Therefore, we recommend choosing sealant with guaranteed quality and reputable brand.