Sealants are versatile products that come in two main forms, which is polyurethane and silicone. Both have their advantages and can be used for various renovation projects, but it is important to know when to use polyurethane sealant over silicone sealant.
Polyurethane is a mastic sealant that is used in high-value projects such as bridge construction and automotive manufacturing. It is hard-wearing and offers superb adhesive attributes that make it useful for projects where speed and strength are a necessity. Contractors like using it for joinery since polyurethane cures rapidly on wooden joints, which may be subsequently painted and sanded for a premium finish. Industries that regularly use polyurethane include:
- Road construction
- Maritime or naval projects
- Building development
The primary difference between polyurethane and silicone is their chemical composition. Whereas silicone is inorganic, polyurethane is an organic polymer. Silicone is better suited to small-scale projects such as food processing and paint creation.
The ideal sealant depends on your DIY project. If it involves paint and the usage of a brush or roller and you want a sealant or adhesive that is close to the finished paint job, you’ll run into trouble if you choose to use silicone. The reason is that you cannot paint over silicone since the organic compounds which comprise it won’t allow paint absorption or adherence on the top layer. If you try it your paint will just peel off.
This is where polyurethane has a significant advantage. Because it’s organic, once curing has occurred it may be sanded and painted over without trouble. This makes it much better than silicone for both small-scale and professional work.
Polyurethane Works Better with Mastic Guns
Some experts believe silicone has greater longevity since it is inorganic and capable of lasting over twenty years. Polyurethane sealant by contrast will last from five to ten years. However, one factor that must be taken into consideration is that polyurethane is harder with better quality. It can handle a higher level of traffic and is crucial for projects that require hardening and a rapid drying time.
The chemical composition between polyurethane and silicone must also be considered since composition is the phenomenon that will determine material breakdown. Any inorganic or organic material which is exposed to sunlight will react differently.
Generally speaking, inorganic materials won’t respond as much to UV rays when compared to organic chemicals. This means that over the longer term, polyurethane as an organic material is susceptible to reverting to a natural state as a result of UV exposure. This will influence both its versatility and lifespan. However, polyurethane sealant sets rapidly and is extremely hard, which makes it ideal for building roads or bridges which have almost continual sun exposure.
Polyurethane is the material of choice for high-level projects because it offers structural bonding for vibrational construction and offers great resistance to a variety of chemicals and will remain elastic once it has been cured. This combined with its adhesive properties makes it indispensable.