Tube, tube in the wall...
It is not easy making the right choice in the jungle of adhesives and sealants. Thanks to the range of brands on offer in DIY shops and trade outlets, a real ‘Great Wall’ of tube products has arisen, one in which even trained professionals can lose their way. Time for some sign posts.
The man on the street and professional users speak of ‘silicone’ when they are talking about the familiar tube products. It’s not entirely correct. TEC7, for instance, is not silicone at all; instead it’s an MS polymer, which is a completely different base material, with different properties.
The first question a user should ask themselves when choosing an adhesive or sealant is: what kind of product am I going to take? If you know the correct product type for a specific application, then the choice becomes a whole lot easier.
In this article, we are discussing the three most common kinds of adhesives and sealants:
- acrylic sealant or painter’s caulk
- MS polymers
Silicone: sealants, not glues.
Silicone kit enjoyed rapid growth in the seventies and eighties. It is a family of products that has extremely high resistance against chemicals and weathering, and UV radiation. It stays flexible, which means it’s excellent for sealing.
The downside of silicone is that it is not such a good adhesive: uneven adhesion and its tensile force is low. In addition, in most cases silicone can’t be painted and it must always be used on a dry surface. Most silicones are not suitable for use on natural stone because the silicone oil stains over time.
A large part of the shop shelves are still taken up by silicone products.
Often they are cheap, mass produced products and the quality is not great. But some types have undergone good development. ROCK7 is a good quality polysiloxane silicone sealant with excellent adhesive properties on difficult surfaces. What’s more, ROCK7 is perfectly safe for use on mirrors and natural stone.
Use a good quality silicone kit like:
- Colourfast glazing kit
- Sanitary sealant
- Sealing kit (can’t be painted)
Painter’s caulk: if moisture or water is a problem
Those who are looking to paint something soon end up with acrylic sealants or painter’s caulk. It is easy to use, can be made smooth and painted quickly. Acrylic sealants keep their shape, but are not very elastic. This means that they are fine for use on walls and in constructions in which there is not much movement. Painter’s caulk is not waterproof and so it should not be used in the bathroom or kitchen.
Just like silicone, the market for this product is dominated by a wide range of cheap products. And the same principle applies here: ‘You get what you pay for’. The better acrylic sealants are more flexible, can be painted over quickly, keep their shape, and can withstand water and moisture more effectively, …
Use a good acrylic sealant/painter’s caulk for:
- Preparing for paintwork
- Filling in and finishing joints in masonry and plastering
- Sealing joints with little movement
- Finishing on plasterboard
MS polymers: all-in-one solution
MS polymers (Modified silanes) like TEC7, X-TACK7 and FLEX7 are the youngest offspring in the sealant family. They combine the advantages of silicone, acrylates, PU adhesives and butyl rubbers. They are adhesives and sealants rolled into one.
The advantages of MS polymers are:
- High adhesive properties on a wide range of materials
- High tensile strength
- Remain flexible and shockproof
- Can be applied to moist surfaces
- Good resistance to chemicals and UV resistant
- Environmentally friendly, solvent-free
- Can be painted
MS polymers are slightly less UV resistant and colourfast than the better silicone kits. This means that silicone is first choice, for instance, as a glass sealant on a south-facing façade. But for almost all other applications, MS polymers are superior.
TEC7 was the first successful MS polymer on the market and, thanks to its protected formula, it remains first in class in terms of a quality, both as an adhesive and a sealant. For tough jobs, X-TACK7 is the preferred partner. With more than 600 kg/m², it is the mounting sealant with the highest initial adhesion. For elastic bonding and sealing, FLEX7 is unbeatable. Its 600% elasticity and exceptional adhesive properties ensure that FLEX7 can tackle even the most distorting constructions.