We hear it almost everyday in our industry, “Its just silicone, whats your cheapest price”. But as when you buy anything, cheaper isn’t always better.

Silicone comes in a few different forms and each one determines not only the price but also the quality and performance.

The three common silicone types are:

  • 100% silicone – This is silicone sealant at its most purest form and with its maximum performance and quality.
  • Optimised silicone – This silicone is usually “Cut” with another substance to make the silicone compound go a little further. Like watering down concentrated orange juice, but usually up to a maximum of 10%.
  • Extended Silicone – This is the silicone that is usually “cut” with hydrocarbons, mineral oils or other similar substance to make the silicone go even further. Like the watered down orange juice, the more water you add, the worst it becomes…


So What are the major differences between a 100% silicone product and an extended silicone product?

1: The performance – The performance of silicone can alter dramatically depending on the volume of extender. Where we see anything between 10% to nearly 40% of extenders in some silicone brands on the market.

  • Movement – The more extenders in the product the more movement the product can lose. This making it less flexible and more prone to failure.
  • Shrinkage – Ever seen silicone ‘curl’on the edges after curing and pulling away from the substrate? This can sometimes be a result of extended silicone shrinking more than normal from to much extenders.
  • Dis-colouration – The oils and extenders can assist in early dis-colouring of silicone. Where your White silicone may turn yellow within 3-6 months. Not ideal on a high-end finish.

2: Price – We all love a great deal, but as the old saying goes “You only get what you pay for” and this is also true in extended silicone. So next time you get a really sharp price on a cheap silicone, ask yourself, is the $1 saving really worth the cost of a potential call back and/or repair bills if it fails or dis-colours?

So how do I know if I have extended silicone?

There are a few tips that can guide you to informing that you may have extended silicone.

  • The float test – This is 90% of the time a quick easy way to see if you have extended silicone, as most cases extended silicone will float. Get a bowl of water, and drop a cured piece of silicone in it. If it floats it maybe extended. If it sinks it most likely will be 100%. Remember this is a guide only and there are some variances that can change this.
  • SDS look up – Find the product SDS (Safety Data Sheet), every manufacturer should be able to supply this to you on request. On the SDS ingredient list you are looking for something along the lines of Hydrocarbons or mineral oil, if you find these you will also see how much it has been ‘cut’ down.

Extended Silicone sds

If you want the best, remember to stick with Admils PROSIL range, this range is a 100% silicone product to meet the demands of professional applications.


Disclaimer: All information in in this document is deemed correct and to the best of our knowledge at time of print and is of general comment only and does not represent professional advice. Admil Adhesives are not liable for any incorrect information supplied. Admil Adhesives and its staff will not be held liable for any loss or damages directly or indrectly caused by any perdsons using the information provided in this document.