Frequently Asked Questions
Do you have questions about silicone sealants? Here you will find competent answers.
Following we have collected for you answers to the most common questions about silicone sealants.
1 Why should I use a silicone sealant and not an alternative sealing system?
Stable quality silicones sealants will last a long time and do not show a high shrinkage as is the case with acrylics. Therefore they are very cost-efficient. Especially in kitchen and bathrooms they are the product of choice.
2 Why should I use silicone sealants from WACKER?
WACKER is a 100-year-experienced company and one of the world’s largest silicone sealant manufacturers. We played a pioneering role in developing silicone sealants and remains a technological leader in this area and offers you state of the art developments. WACKER is your reliable partner regarding innovative products, stable quality, security of supply and perfect sealing.
3 How should I prepare the substrate surfaces before sealing (or primering)?
The substrate areas that will be in contact with the sealant must be clean, dry and free of all loose material such as dust, dirt, rust, oil and other contaminants. Non-porous substrates should be cleaned with a solvent and clean, lint-free, cotton cloth. Remove residual solvent before it evaporates with a fresh clean, dry cloth. For application from cartridges cut thread open, fix nozzle on top and cut to required bead size. The sealant can be applied in beads or layers. It requires moisture in order to cure.
The adhesion can be improved in many cases by pretreatment of the substrate with a primer. Clean the surface in a similar manner as prior to applying the sealant.
4 What to watch out for when applying the sealant?
Ensure the depth of the sealant is not greater than the width. For larger spaces between the two substrates, including backing material will improve the sealant performance. Smoothing down the sealant with an appropriate tool, will give a better surface appearance. . This step forces sealant into joint surfaces and helps remove air pockets or voids at the bond line.
5 Why do architects favor silicone sealants for exterior application?
Silicone sealants exhibit excellent UV resistance versus alternative systems such as PU.
6 When should I use an acetoxy system?
Acetoxy sealants have excellent adhesion to glass or ceramics – typical surfaces in the bathroom or kitchen.
7 When should I use a neutral system?
Neutral sealants must be used where metals, plastics or concrete are the substrates to be sealed. They are particularly suitable as non-corrosive sealing solution for connection and expansion joints.
8 Can I use any silicone sealant for natural stone?
Standard silicone sealants will always tend to bleed somewhat. Therefore WACKER has a solution developed for natural stone such as marble, granite, sandstone and quartzite to eliminate this problem.
9 Can sealants be used after their use by date?
We do not recommend use of our products beyond their usable life.
10 Can I use a silicone sealant as an adhesive?
WACKER’s construction silicone sealants were developed to seal e.g. two joints and therefore remain elastic. Silicone sealants were not developed to act as an adhesive which is traditionally much stiffer. If an adhesive is sought please do address us for our hybrid range.
11 Can silicone sealants be exposed to harsh cleaning agents?
Silicone sealants will generally withstand typical household cleaning agents, but check suitability as exposure to strong acids or alkalines could disturb the appearance and the performance of the sealant.
12 What is meant by specialty?
Specialty Silicone Sealants refers to sealants developed for applications where particular characteristics are required.
A food grade sealant where a sealant does not react with certain foods and result in toxin formation.
A natural stone sealant that does not bleed plasticizer leading to staining.
A high temperature sealant that will withstand extremely high temperature ranges when used to seal say a chimney cornice.
A fire retardant sealant that releases water [via the filler] during burning that will extinguish the sealant.
An aquarium sealant that is suitable to seal the glass panels of an aquarium – within given dimensions.
13 What if I have an application exposed to temperatures beyond 150°C ?
For high temperature applications a special silicone sealant has been developed – WACKER® 180 – HIGH TEMPERATURE, this sealant withstands temperatures of upto 250°C.
14 How do silicone sealants react with paint and painted surfaces?
Silicone sealants are essentially not paintable. Select hybrids or acrylics, if paintability is desirable. It is advisable to paint surfaces first before applying a silicone sealant.
15 How can I remove a cured sealant?
Cured silicone can be removed from a surface with a sharp blade.