Silicone and sealants

What is construction silicone?

Behind this substance stands a material produced artificially from silicon and oxygen. Silicon is abundant on Earth and, therefore, is a good resource. Silicone combines organic and inorganic substances, which is why it is often called "intermediate" or hybrid. No other plastic can possess the properties that silicone provides.

There are two main types of silicone: acetoxy and neutral silicone. The first category reacts with moisture and releases a solvent in the process. The second category is made on a water base and evaporates when it dries.

Thanks to its elastic, stretchable, and flexible properties, silicone finds application in many areas, especially in the construction sector.

In construction and finishing repair work in homes and offices, the following types of silicone are familiar:

• Sanitary silicone;
• Kitchen silicone;
• Bathroom silicone;
• For bonding;
• For marble and natural stone;
• High-temperature resistant.

The unique properties vary and include elasticity, resistance to cold and heat.

Acrylic silicone

Silicone and acrylic are among the most common sealants. Both are used by professionals, craftsmen, and hobby enthusiasts. There are different products suitable for indoor or outdoor use, or optimized for specific requirements (heat resistance, fire resistance, etc.).

The appearance and consistency of acrylic and silicone sealants are quite similar at first glance, but there are significant differences between the two substances. Below, we discuss in which areas silicone is more suitable, why you should use acrylic, and when you can freely choose between acrylic and silicone.

For sealing

Silicone for sealing, offered by ATEK 1 at reasonable prices, is used to fill and seal joints, repair cracks, gaps, and smaller openings, and to clean joint areas. Due to its adhesive strength, they can also be used for attaching components. However, since they don't bond like construction adhesives, for example, this works only for lightweight, small, and/or less stressed parts, such as attaching decorative tiles and sills.

During renovation and finishing work, construction silicone is mainly used for grouting in kitchens and bathrooms, for eliminating defects in the basement (e.g., cracks in plaster or masonry), and for sealing and concealing connection points on baseboards, sills, countertops, wall and floor tiles, sills, door frames, cable ducts, blinds, etc.

Due to its water resistance, various types of construction silicone are still the first choice in the kitchen and sanitary areas, such as sinks, countertops and stands, shower walls, tubs, and toilets. Silicone should also be used for acrylic tubs and other sanitary plastics. Different manufacturers, like Knauf, offer special silicone sealing compounds at an affordable price.

For outdoor use, there are special silicones that are particularly resistant to atmospheric influences and can withstand high heat, cold, and UV radiation.

Another advantage of silicone is that it insulates against electricity.

Silicone is also used to make easy-to-use various models of silicone seals, which can be easily attached to windows and doors to improve insulation. These silicone seals can vary in color and profile, so everyone can choose according to their own goals.

Silicone adheres very well to various substrates such as concrete, stone, glass, wood, plastic, as well as fiberglass and plasterboard. Unlike silicone, acrylic can be easily painted or applied to wallpapers.

Differences between acrylic and silicone

Both sealant mixtures have a paste-like consistency before processing, with silicone resembling rubber more, and acrylic more akin to putty. Compared to acrylic, silicone is significantly brighter and stickier. If you rub both substances between your fingers, silicone forms a stubborn, sticky film of grease, while acrylic forms small lumps that can be easily removed from the skin.

Wet acrylic sealant is also water-soluble, whereas silicone can only be removed with the help of a tool (e.g., spatula, blade), a lot of washing liquid, grease, or special silicone removal fluids.

Both acrylic and silicone remain elastic after curing. The elasticity of rubber-like silicone is much higher than that of acrylic. As a result, silicone joints can stretch much longer before cracking, which is why silicone is generally more suitable for expansion joints and for compensating for the movements of components (e.g., in plasterboard construction).

When you touch a cured acrylic joint, it feels almost hard - similar to putty for window glazing. Cured silicone is softer and, similar to solid rubber, still yields to pressure upon application. The shine of silicone is also largely preserved after drying, while dry acrylic is matte.

Heat Resistance

Home improvement enthusiasts are familiar with the qualities of good construction silicone mainly as a sealant for joints, but some people also appreciate it in the kitchen. It provides valuable assistance in everyday life. In some cases, it's important for silicone to withstand certain temperatures. There are different levels of heat resistance that should be observed depending on the design and use.

Different Levels of Silicone Heat Resistance

Silicones are inherently heat-resistant. However, there are substances with different temperature limits. Heat-resistant silicones are mainly divided into the following categories:

• Up to 150 degrees Celsius
• Up to 300 degrees Celsius
• Up to 600 degrees Celsius
• Up to 1000 degrees Celsius
• Up to 1500 degrees Celsius

The most commonly encountered silicones belong to the first category. Information about the different products should be read carefully because a distinction is made between short-term and long-term stress. Silicone cannot constantly withstand certain temperatures!

What Heat Resistance for What Purpose?

Conventional silicones are thermally resistant up to 150 degrees and are ideal for sealing joints on the kitchen stove, for example. The second category finds application in the automotive sector. Silicones that are heat-resistant up to 300 degrees can be found, for example, in sealing engines, gears, and other areas of electronics. Boilers, dryers, and air conditioners are also sealed with these materials.

Products that withstand temperatures above 250 degrees Celsius are called high-temperature silicone. When sealing chimneys and heating elements, silicone that is heat-resistant up to 1000 degrees Celsius is usually used. Silicone with heat resistance up to 1500 degrees is used, for example, in furnaces.

They are more likely to be found in the industry than in the "Do It Yourself" sector. In this case, silicone is often even fire-resistant. In conventional versions, silicone belongs to fire class B2 - usually flammable. However, with special models, the fire-resistant level B1 can be achieved.

The heat resistance of silicone is useful not only for sealing hot spots. The material also helps in the baking area - such as silicone baking molds. These utensils are usually heat-resistant up to 260 degrees. They are also food-safe and non-toxic. There are also heat-resistant silicone cooking gloves.