Which silicone I should use for medical applications?

None of our silicones are suitable it be used for medical purposes.

Is the temperature of the application surface important?

Yes, it is important. Do not apply silicone on surfaces below - 10°C and above 50°C. 

Can I use single component silicones on narrow and closed gaps?

Single component silicones require humidity to dry. For that reason, if they are applied to gaps which do not contact air, they might not completely dry.

Can I use silicones as adhesives?

None-solvent containing 100 % silicones can be used as adhesives. Promast Universal and Promast Neutral are none-solvent containing pure silicones. They contain additives to ensure strong adherence to various surfaces.

Can I use silicones as adhesives?
If I am applying silicone on plastic surfaces, which type I should choose?

Plastic surfaces are the hardest to adhere. Especially like in the case of PE and PP, adhering silicones to plastic is impossible.

Nevertheless, adhering to PVC-like plastics is possible by using neutral silicones.  


Are silicones resistant to high heat?

Yes, compared to a number of organic sealants, endurance of silicones to heat is remarkable. 

100 % pure silicones maintain their elasticity up to temperatures between 150° C - 180° C. However the heat endurance on high solvent containing cheap silicones can go down to temperatures between 90° C – 120°C.

On the other hand, high temperature silicones, also known as liquid joints, can endure temperatures up to 250°C - 300°C.

The shelf-life of the cartridge I have is expired but the silicon seems ok.

You are right, although its shelf life is expired, silicone might seem normal. But the problem is, it might not dry out. 

Expiration of their shelf life does not demonstrate itself in the cartridge by thickening or hardening but they lose their ability to adhere.

Use a small portion of the silicone to see if it is still drying out or not. 


The shelf-life of the cartridge I have is expired but the silicon seems ok.
Silicone is dried out in its cartridge!

This is a very rare situation. Contrary to polyurethane sealants, silicones do not dry out inside the cartridge.

Probable reasons for that might be; perhaps the cartridge got air or as manufacturing mistake large quantities of humidity has been let inside the cartridge during production.

At what temperature should I store silicones?

Storing between 5°C to 25°C is ideal for maximum shelf life. Below -5°C some chemicals inside silicones crystallize. To circumvent this problem, silicones should be warmed up to the room temperature.

When stored at temperatures 35°C and above, there is a significant loss on the shelf life of the product.


What are the properties of Promast Aquarium Silicone?

This is a none-solvent containing 100 % silicone. Because of that, it dries out quickly and adheres very strongly.  Additionally it does not contain poisonous additives which are found in most silicones as a standard and which may harm fish (i.e. fungus killing poison).

Which types of silicones are more appropriate for wood surfaces?

For affixing wood neutral silicones yield better performance. They can not only adhere the wood onto each other but to concrete, brick and similar other surfaces.

Promast Building Construction Silicone is a great choice for your woodworks. 

Which types of silicones are more appropriate for wood surfaces?
What should I know about acetoxy silicones?

Acetoxy silicones are the ones with strong odor. Actually they do not contain acids however since they secrete strong acids during their drying process, that’s why they were named like that.

They are not used in basic surfaces such as concrete, brick or marbles. Additionally, the acid secreted may harm mirrors, galvanized metals and sensitive metals such as brass and copper. 

On the other hand, they adhere very strongly on glass, tiles and similar surfaces. Morover, they dry out very quickly.

Are silicones resistant to acids and bases?

Acids and high levels of basic chemicals may cause great damage to the surface the silicone is adhered and the adhesion strength in time.

Can I use silicones for gas proofing?

Unfortunately, this is not possible. Silicones cannot ensure proofing for vaporous gasses such as oxygen and carbon monoxide. 

Gas and vapor permeability of silicones are high. Because of this property, single component silicones dry out fast.

Silicone is dried out in its cartridge!

Yes, this is possible. Just leave them in room temperature for a short while and make a small test. If it crusts within 15-25 minutes, it means it can be used. 

Can I determine solvent levels in silicones by my own means?

No, you cannot. This can only be done by very specific tests. However, with clear silicones you might have a guess. Pure silicon – although called transparent- is not totally transparent; it is translucent with a whitish color. However, the more solvents used the more crystal clear transparent it becomes.

Additionally with increased quantities of solvents, the consistence of the silicone decreases most of the time. Silicone dries out very slowly. There would be apparent weakening in its adhesion. 

What makes cheap silicones cheap?

 A type of odorless organic solvent used in manufacturing some silicones is what makes them cheap. These solvents are used up to 45% to reduce the retail price of the product. As can be imagined, these solvents vaporize and leave the silicone in months. In the end the silicone turns into a substance where its volume is halved and which can be dislocated from its place easily. 

What does Natural Stone Silicone mean?

Common silicones contain various plasticizers (silicone oil, organic oil, etc.).  When silicone is applied to porous surfaces like marble or granite, these oils may seep into the pores. In time there would be esthetically unpleasing stains on the application surface.

The silicones which do not stain natural stone surfaces since they are produced without plasticizers are called natural stone/marble silicones. 

What does Natural Stone Silicone mean?
I couldn’t paint over silicone!

Silicones are not paintable sealants. For that reason, it is better to opt for a color silicone matching to the application area.

What does neutral silicone means?

If the chemicals released during drying process of a silicone are neutral (PH 7) or weak acids (PH 5.5) those silicones are called neutral silicones.

Contrary to acidic silicones, neutral silicones do not secrete a foul odor and do not corrode acid sensitive surfaces.

What does neutral silicone means?
What is the difference between the high temperature silicone and the incombustible silicone?

High temperature silicones (liquid joint) do not lose their elasticity when exposed to heat between 250°C - 300°C and maintain their mechanical properties. However, when exposed to flames, they are indeed combustible.

On the other hand, incombustible silicones do not catch fire and they are fireproof. Yet, they cannot endure temperatures above 180°C.

To give an example, high temperature silicones can be used at the engine of an automobile and incombustible silicones can be used around an electric panel. 

What does RTV silicone mean?

RTV is an abbreviation of Room Temperature Vulcanization used for silicones cured at room temperature. It means silicones which do not require high temperatures for hardening.

In this context, almost all of construction silicones can be said to be RTV silicones.

However, in our country RTV silicone is used for silicones which are high heat resilient after drying (liquid joint).

Why don’t you produce a neutral silicone for aquariums? Doesn’t acetoxy silicone harm the fish?

For affixing glasses, acetoxy silicones are the leader of the pack by far. Besides, what harms the aquarium creatures are not the acids secreted during the drying process, but probably desorption of solvents present in the silicone and antibacterial fungus poisons.

You mention 100% silicones, what does this mean?

100% silicone is used to denote pure silicone. In order words it is a none-solvent containing silicone… The practical results are; fast drying, strong adherence and most importantly increased implementation life without volume loss.

You mention 100% silicones, what does this mean?
You have both acetoxy and neutral silicones for wet surfaces, which one I should prefer?

If the surfaces you will apply silicone are natural materials such as glass, tile or wood acetoxy silicones ensure strong adherence. Using neutral silicones might be a better option for acid sensitive surfaces, aluminum, steel and plastic.

You have both acetoxy and neutral silicones for wet surfaces, which one I should prefer?
The silicone from the cartridge came out runny, almost like water!

Colorless odorless organic oil could be mistaken for water. Generally this problem appears when very cheap, low quality silicones are stored in very low temperatures. You might empty out the oil coming out of the cartridge and use the leftover silicone. Because the silicone does not lose much from its performance.

Ideally it is better to use 100 % pure silicones not containing organic oils which are a sort of solvent and causes high volume loss. 

Look as if silicones turn yellow sometimes?

Acetoxy silicones very rarely turn yellow however neutral silicones, if exposed to chemicals (for example leftover adhesive on the surface) might turn yellow.

What should I be careful about applying silicones in a bathroom?

Make sure all application surfaces are cleaned thoroughly because this would increase the utilization life of the silicone. You might use solvents like thinner or benefit from bleach with the condition that you rinse it with plenty of water.

What is the best silicone for my bathroom?

Smile! The answer is the easily removable silicone. Bathrooms are generally exposed to excessive humidity and heat. If they are not dried out and left wet for a long period, even the most endurable silicone would darken in three years the most and would be esthetically very unpleasing.

Nevertheless, if you make sure that the silicone you used in your bathroom is a none-solvent containing 100% silicone and it contains anti-fungus additive (antibacterial), you might expect the highest performance possible. 

What is the best silicone for my bathroom?
Can I use my Kitchen & Bathroom silicon on outdoor surfaces?

It is better if you don’t. Because these silicones are designed specifically to be used indoors. If used outdoors, it might turn yellow.

For maximum performance, use only the silicones designed specifically for an application area.

Why did the silicone I applied to my bathroom peeled off in three months?

You might have used a high solvent containing cheap silicone. When applied to the bathrooms, silicones very quickly lose cost cutting solvents. As result, only within months silicones declining to half of the volume they were initially applied could easily peel off.

Why the silicones are used very commonly?

Both in the world generally, as well as in our country the most common sealant used after water-based and acrylic based sealants are silicone sealants. This is closely related to the fact that silicone based sealants are more durable, more water resistant and can endure adverse weather conditions as well as temperature differences. 

Why the silicones are used very commonly?