A Silicone building sealant is cured by condensation of volatile small molecules through chemical reactions. According to the different chemical reactions, the different small molecules, silicone building sealant can be classified. There are two kinds of products in circulation on the market: one is acid sealant. This kind of product is acidic, and the small molecules released when curing are acetic acid, which has a sour taste and is corrosive to some metal materials, and also has a certain irritation and corrosion to the human body. Another kind of product is neutral sealant, this kind of product is neutral, according to the different small molecules released in the curing process is divided into alcohol glue and ketone oxime glue. Alcohol-type adhesive and the small molecule released during curing is methanol, which is non-corrosive and pungent. Ketoxime glue curing when released ketoxime, smellier than alcohol sealant. These two kinds of products are different in smell and nature.

A Building sealant can be classified according to different methods, such as the structural sealant and non-structural sealant described above, which is based on the strength requirements combined with the application of the classification.
The more common classification is by chemical composition. According to the chemical composition of the basic sealant, the sealant can be divided into polysulfide, polyurethane, silicone, neoprene rubber, butyl rubber, acrylic glue and so on. At present, the large amount of the market is organic silicon, polyurethane, polysulfide.

Building sealant is classified into single component and double component packaging according to the packaging method. Single component packaging is to mix all the raw materials of sealant together, sealed and packed in plastic bottles or flexible packaging aluminum film, and use glue gun to beat the product out of the packaging. Two-component packaging is composed of two components: A and B. In general, A component is the base compound, and B component is the curing agent. Filler and other additives according to the need to join in A component and B component, when using special mechanical equipment (two-component glue machine), A, B component according to the prescribed proportion mixed evenly, A, B component chemical reaction curing, separate A component or separate B component are not used.  

According to the curing characteristics of sealant can be divided into chemical reaction type, solvent volatile type, heat capacity cold setting type and other different categories. Silicone sealant belongs to the chemical reaction type.

A Building sealant is a kind of paste building sealing material composed of basic glue, filler, curing agent and other additives. After using, it will cure into elastic rubber material, bonded to the building base material, and play the role of sealing, waterproof and leakage prevention. It is mainly used in the joint sealing of buildings. As a kind of building adhesives, it is significantly different from other building adhesives such as glue in morphology and application. Other building adhesives are generally fluid, mainly used for bonding and pasting building decoration materials, and have no sealing effect.

Building sealant according to the role of different can be divided into two categories: one is the building structure sealant, the other is non-structural sealant. Building structure sealant, also referred to as structural sealant, is used in the production of curtain wall unit parts on glass and other building plates play a structural bonding and sealing role, these plates are completely by structural adhesive on the frame, there is no other fixed connection. Therefore, structural adhesives have strict requirements for strength and adhesion. Beside structural sealant, all other sealant is non-structural sealant. The role of this kind of glue is joint sealing, not structural bonding, so there is no strict requirement for strength, as long as it can be adhered to the base material to play a sealing role. Because to take into account the effect of thermal expansion and cold contraction of the base material on joint expansion, the sealant must have better elasticity and displacement ability.