Commonly Used Sealing Materials for Doors And Windows - Sealants

The sealants for aluminum alloy doors and windows mainly include sealants for glass inlay, sealants for hollow glass, sealants for the joints between door and window frames and openings, etc.

The main components of elastic sealants for aluminum alloy doors and windows and glass inlay are silicone, modified silicone, polysulfide, polyurethane, acrylate, butyl rubber, styrene-butadiene rubber, chloroprene rubber and other polymer materials.

(1) Sealant for glass inlay

There are two types of sealing for aluminum alloy door and window glass: dry method and wet method. Dry inlay uses sealing strips for sealing, while wet inlay mainly uses single-component elastic sealant that cures at room temperature for sealing.

Currently, the most commonly used ones are silicone sealants, polyurethane sealants, and polysulfide sealants.

The sealant between the glass and the window frame should comply with the "Elastic Sealant for Building Windows"

(2) Sealant for insulating glass

Sealant for insulating glass can be divided into two categories: thermoplastic and thermosetting.

Thermoplastic insulating glass sealants include hot-melt butyl sealants and polyisobutylene sealants (PIB).

Thermosetting insulating glass sealants include polysulfide sealants, polyurethane sealants, and silicone sealants.

The first sealant for insulating glass usually uses hot-melt butyl sealant, which is airtight and watertight, but has no strength. The second sealant can be selected from polysulfide sealants, polyurethane sealants, and silicone sealants according to the situation.

Polysulfide sealants are prone to aging under ultraviolet rays and can only be used for insulating glass installed by the inlay groove clamping method.

The second-line sealing of insulating glass for concealed frame doors and windows, concealed frame or semi-concealed frame curtain walls, full curtain walls, and point-supported curtain walls must use silicone structural sealants.

For structurally installed insulating glass, since the sealing system is required to have extremely high adhesion and UV resistance, polyisobutylene structural adhesive and silicone structural adhesive must be used for double-line sealing.

Silicone structural sealants for insulating glass should comply with the "Silicone Structural Sealant for Insulating Glass"

Elastic sealants for insulating glass should comply with the "Elastic Sealant for Insulating Glass" and "Elastic Sealant for Insulating Glass for Building Doors, Windows and Curtain Walls"

Butyl hot-melt sealants for insulating glass should comply with the provisions of "Butyl Hot-melt Sealant for Insulating Glass".

(3) Sealant for the joints between door and window frames and openings

Elastic sealants are mainly used for sealing the external joints between door and window frames and openings, while acrylic sealants based on acrylic emulsion can be used for sealing the internal joints.

The sealant between the window frame and the opening should comply with the provisions of "Silicone and Modified Silicone Building Sealant" and "Acrylic Building Sealant".

(4) Selection of sealant

The compatibility of sealant refers to the property that the contact surface between the sealant and other materials does not produce adverse physical and chemical reactions. The adhesion of sealant refers to the adhesion performance of sealant on a given substrate.

① Sealant products with good compatibility and adhesion with the bonding material should be selected. After the manufacturer selects the sealant, it should conduct compatibility and adhesion tests. Only sealants that pass the compatibility and adhesion tests can be used.

② Glass inlay sealants need to withstand long-term sunlight ultraviolet radiation, so sealants with good weather resistance and aging resistance and good compression permanent deformation performance should be selected.

③ Glass inlay sealants and building joint sealants are two sealants with different uses and cannot be interchanged at will.

④ When selecting sealants for the joints between door and window frames and openings, the type, nature, size and hardness of the bonding materials, shape structure and process conditions, loads and forms (tensile force, shear force, peeling force, etc.) borne by the bonding parts, and special requirements of the materials (such as electrical conductivity, thermal conductivity, high temperature resistance and low temperature resistance) should be considered.

⑤ Before using silicone structural sealants in projects, material compatibility tests should be conducted by nationally recognized testing agencies. Products that fail the inspection shall not be used.

Expired silicone structural sealant products shall not be used. During the use and construction of structural sealants, products of the same brand and batch number should be used. Structural sealants from different companies have different product formulas and production processes, and different product batch numbers also have differences in quality. Therefore, structural adhesives and weather-resistant adhesive products shall not be mixed in the same project.

⑥ Sealants must be used within the validity period.