Understanding MS polymer sealant | modified silicone sealant AS4001 kiến thức mới năm 2023

MS polymer sealant  has various names such MS (Modified Silicone/Silane) Polymer sealants – a.k.a. Hybrid, STPE (Silyl Terminated Polyether), or SMP (Silyl Modified Polymer) sealants – MS polymers are products of Kaneka Corporation Japan – most used type of construction sealant in Japan since over 30 years ago, combining the strengths of PU and silicone sealants without their inherent weaknesses.

MS polymer sealants, also known as “Modified Silicone” or “Hybrid” sealants, use a modified silane polymer as their base instead of the synthetic polymer base of silicone or the urethane-based polymer system utilized by polyurethane sealants. For example, MS polymers possess the durability and paintability of polyurethane without the shrinkage commonly associated with polyurethane chemistries. It also has silicone’s weather and UV resistance while still standing up to abrasion.

The innovative hybrid chemistry of MS polymer sealants offers many unique benefits. The silane-terminated foundation makes MS polymer sealants free of isocyanates. Isocyanates are highly reactive chemicals, which upon reaction with moisture in the air or from the substrate, releases Carbon Dioxide (CO²). These CO²2 molecules form bubbles or voids within the sealant, creating an uneven appearance. Over time, these bubbles and voids can compromise the strength of the sealant, resulting in a cohesive failure.

This lack of moisture-reactive isocyanates means MS polymer sealants will adhere to wet substrates, which isn’t possible for polyurethane or silicone sealants. This wet-surface adhesion makes MS polymer sealants.

MS polymer sealants contain no solvents, unlike many polyurethanes. Since the main chain does not have highly cohesive segments, solvents aren’t required. The result is a low viscosity, low odor sealant that offers excellent gunnability even at low temperatures.

When sealants containing solvents cure, the solvents will evaporate, and shrinkage occurs. This shrinkage detracts from the seam’s neat and clean appearance and can reduce the seal’s performance. As the product shrinks, it can contribute to cracking and even loss of adhesion. Since MS polymer sealants contain no solvents, they will experience limited to no shrinkage.

Beyond impacting performance, isocyanates and solvents also pose serious health concerns. Isocyanates can irritate the eyes, nose, throat, gastrointestinal system, and skin. They can also cause pneumonitis, which is inflammation of lung tissue.

Many solvents used in caulks and sealants are Volatile Organic Compounds (VOCs) which can adversely affect the health of building occupants. Sealants with high VOC levels may not comply with green-building initiatives like Green Guard or LEED. MS polymer sealants’ lack of isocyanates and solvents makes them excellent for use in green building projects, hospitals, schools, or any application where limiting VOC exposure is essential.