To produce high-performance alkoxy system sealants that release alcohol during curing, it is essential to select appropriate resins, crosslinkers, and catalysts. Silane crosslinkers play a crucial role in this process by promoting efficient curing, enhancing adhesion, and optimizing the final sealant properties. Below are three recommended formulations for different types of alkoxy sealants based on the alcohol released during curing and the desired sealant colors.

For Methanol-Releasing Alkoxy Sealants (e.g., Black, Gray, etc.)

For alkoxy sealants that release methanol during curing, we recommend the following system:

• Resin: OH Polymerwith a viscosity of 30,000 - 50,000.

• Crosslinker: Siwin-931 (Methyltrimethoxysilane).

• Catalyst: Siwin-TIC01 (Tetraethoxysilane).

This combination ensures efficient curing, providing excellent flexibility and adhesion, while also enhancing the durability and weather resistance of dark-colored sealants such as black or gray. The use of Siwin-931 ensures a quick and stable curing process, while Siwin-TIC01 acts as a catalyst to promote faster crosslinking.

For Ethanol-Releasing Alkoxy Sealants (e.g., Black, Gray, etc.)

For ethanol-releasing alkoxy sealants, we recommend the following formulation:

• Resin: OH Polymer with a viscosity of 30,000 - 50,000.

• Crosslinker:Siwin-ND43 (Dichloromethyltriethoxysilane).

• Catalyst: Siwin-ND22 (Amino-functional silane).

This system is designed for sealants that require a slower curing process and enhanced flexibility. The use of Siwin-ND43, which contains a dichloromethyl group, helps achieve superior crosslinking efficiency and bonding strength, particularly in dark-colored sealants. The catalyst Siwin-ND22 ensures optimal curing speed and provides enhanced moisture resistance, making it suitable for sealants exposed to harsh environments.

For Light-Colored Alkoxy Sealants (e.g., Transparent, White)

For light-colored alkoxy sealants, such as transparent or white formulations, we recommend two different systems based on the type of alkoxy endcap used on the resin.

Wacker Way (Trimethoxy Endcapped OH Polymer):

Resin: Alkoxy-endcapped OH Polymer, Siwin-TMOH20000-TMOH80000 (Trimethoxy endcapped OH polymer), with a viscosity ranging from 20,000 to 80,000.

Crosslinker:Siwin-931 (Methyltrimethoxysilane).

Catalyst: Siwin-DBTDL (Tin catalyst).

This system provides excellent transparency and adhesion properties, making it ideal for sealants used in applications where appearance and durability are key concerns, such as in construction or automotive glazing.

Dowsil Way (Dimethoxy Endcapped OH Polymer):

• Resin: Alkoxy-endcapped OH Polymer, Siwin-DMOH20000-DMOH80000 (Dimethoxy endcapped OH polymer), with a viscosity ranging from 20,000 to 80,000.

• Crosslinker:Siwin-931 (Methyltrimethoxysilane).

• Catalyst: Siwin-TIC02 (Titanium-based catalyst).

The Dowsil method provides a slightly slower curing rate, which can be beneficial for applications requiring more workability time. This system is particularly useful for light-colored or translucent sealants that require a high level of transparency and smoothness.

The use of silane crosslinkers is essential for the effective curing of alkoxy silicone sealants. By selecting the appropriate crosslinker and catalyst combination based on the alcohol released during curing and the desired color and properties of the sealant, manufacturers can achieve optimal performance. Whether producing dark-colored sealants that release methanol or light-colored ones requiring enhanced transparency, these recommended systems provide excellent adhesion, flexibility, and resistance to environmental factors, ensuring the durability of the sealant in demanding applications.