When it comes to sealing joints and surfaces, sealants are essential to ensure that no water or air penetrates through them. There are different types of sealants available in the market, but the two most commonly used are silicone and polyurethane sealants. 

Understanding the differences between these two sealants can help you choose the one best suited for your project.    

Composition and Properties

Silicone sealants are made from silicone polymers and contain different additives such as pigments, fillers, and plasticisers. They are known for their excellent adhesion, flexibility, and resistance to extreme temperatures and weather conditions. Silicone sealants also have low shrinkage, which makes them ideal for sealing joints and gaps.

Polyurethane sealants, on the other hand, are recognised for their exceptional strength, durability, and resistance to impact, abrasion, and chemicals. They are formulated using polyurethane polymers, which are combined with various additives such as catalysts, fillers, and solvents. These sealants also have excellent adhesion and can bond to multiple surfaces, including concrete, wood, and metals.

Applications

Sealing joints and gaps in windows, doors, and other building elements, as well as electrical equipment, automotive parts, and plumbing fixtures, is a common application of silicone sealants. They are particularly suitable for outdoor environments that require flexibility and resistance to temperature changes.

Polyurethane sealants find frequent applications in the construction industry for a variety of purposes. They are often used to create joints, expansion joints, and concrete joints, as they offer superior sealing properties. They are also employed for bonding and sealing metal, wood, and plastic components.

Installation and Maintenance

Silicone sealants are easy to install and can be applied with a caulking gun. They also cure quickly and require minimal preparation and cleanup. In addition, these sealants require little maintenance and can last for years without deteriorating or losing their adhesion.

Unlike silicone sealants, polyurethane sealants need more preparation and cleanup. Additionally, they have a lengthier curing process and may require primers or activators to ensure they adhere correctly. Maintaining these sealants may also be more demanding and require more frequent recoating or replacement than silicone sealants.

Cost

Although silicone sealants have a higher upfront cost than polyurethane sealants, they are more cost-efficient in the long run. This is because silicone sealants require less maintenance and have a longer lifespan than polyurethane sealants.

Polyurethane sealants are generally less expensive than silicone sealants. However, they may require more maintenance and need to be replaced more frequently, which can increase the project’s overall cost.

Environmental Impact

Silicone sealants are widely regarded as environmentally friendly because they are non-toxic, non-flammable, and release low levels of volatile organic compounds (VOCs). Additionally, their resistance to UV radiation decreases the need for replacements, which reduces waste and minimises environmental impact.

In contrast, polyurethane sealants are regarded as less environmentally friendly due to their high emissions of VOCs when being installed and cured. The production of these sealants also requires more energy and resources, contributing to a higher carbon footprint.

Final Thoughts 

Silicone and polyurethane sealants have unique properties and advantages that make them suitable for specific applications. When choosing a sealant, consider factors such as composition, properties, applications, installation, maintenance, cost, and environmental impact. With the right sealant for the job, you can ensure that your project is completed to the highest quality, durability, and sustainability standards.

Quality Seal Australia takes pride in providing high-quality silicone and caulking services on the Gold Coast. Our caulking contractors are trained and experienced in selecting and applying the best sealants for each project, ensuring that your home or building is protected from moisture, drafts, and other environmental factors.

For enquiries, call 0756060208 or email us at office@qualitysealaustralia.com.au.