Polyurethane Sealant vs Silicone Sealant vs Polymer Sealant

Polyurethane and silicone based products have long been the go-to choice for sealing. These types of sealants can be used on most building materials and work effectively in a variety of conditions.

They come in handy for filling gaps and ensuring a water tight seal. They also provide a neat and tidy finishing touch to any construction project. They are resistant to UV exposure.

 Improved Safety, Better Health Outcomes for Tradies

Many people do not realise that some types of silicone contain an inorganic material called isocyanate. This is a harmful substance which can irritate the skin, eyes, nose and throat and contribute to the development of asthma. It has also been linked to cases of chemical bronchitis, gastrointestinal irritation and pneumonitis. The same is true for polyurethanes, although polyurethanes are organic materials.

Improved Cohesion Strength Across all Substrates

There are a few surfaces which Silicone has trouble adhering to. In addition to this, silicone is an inorganic compound not as strong or durable as polymer based products. These, in contrast offer long lasting protection.

Polymer has a much greater cohesion strength. Tests show that it can remain flexible up to 350% at the break point, compared to about 280% with silicone. 

Superior Finish, Endless Colour Options, Easy to Work With

One of the most common complaints with silicone is the drying time. This can result in a less than impressive finish due to airborne particles or acts of vandalism. Bubbles are another issue, and silicone is only able to be painted over with enamel based paints.

UV Resistance

There are a wide variety of polymer products on the market, but not all resistance to UV light. Damage from UV rays can significantly shorten the lifespan of the product due to cracking, discolouration and disintegration. In applications where UV resistance is necessary, carbon black can be added to the polymer to assist with UV resistance.

Polymer – The Smart Choice

In summary, polymer is:

  • Highly durable – harder than silicone, capable of withstanding high external forces and extreme climatic conditions. Expands and contracts as it’s exposed to the weather. Forms a seal preventing water and air escaping a system. Polymer solutions are typically good for a 5 year warranty.
  • Easily Customisable – choose from extensive natural state colour range. Or, simply paint over with your choice of paint, including water-based paints.
  • Safe – no isocyanate, does not irritate skin or cause occupational health issues and it is also environmentally friendly.
  • Aesthetically Appealing – cures smooth, does not bubble or attract dirt.
  • Superior Cohesion – adheres to many different substrates, more resistant against expansion/contraction.
  • UV Resistant – Polymer can have various blockers, absorbers and stabilisers added to improve UV resistance. This makes it ideal for long-term use outdoors and in sunny environments.


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