New generation MEKO-free oxime bonding and sealing products

Breaking out from traditional oxime technology

RTV (Room Temperature Vulcanizing) oxime silicones are useful for many purposes as sealing and bonding products. RTV sealants can be used for electronic sealing and/or bonding as well as engine gasketing, to name a few key applications.

There are numerous technologies available for oxime to achieve vulcanization without heating, in particular moisture-curing systems. These processes are often based on the traditional oxime technology where Methyl Ethyl Ketoxime (MEKO) is released while curing. In 2014, European regulators classified MEKO as an H-351 carcinogenic category 2 product, which meant that manufacturers were required to add the carcinogenic pictogram on Oxime silicones, to warn users that these products were potentially hazardous for their health. Even though our customers were satisfied with the traditional product and generally took precautions when using it (in particular, proper ventilation of work spaces), the Elkem Silicones R&D department decided to develop innovative MEKO-free oxime technology. 

Anticipating future sealant market regulations

The new MEKO-free oxime silicone developed by our R&D specialists offers an all-in-one solution that covers virtually every sealing and bonding application, for both indoor or outdoor use and of course is much safer for users. In fact, our new formulation not only complies with current European health & safety standards, but actually anticipates on what we think will be the future guidelines, in that MEKO-based sealants will be further restricted.

Our customers are discovering every day that our new formulations deliver the same curing speed, quality sealing, adhesion and mechanical properties that they have appreciated for many years using the old technology. This agility and determination to adapt to changing markets and regulatory requirements are the hallmarks of our R&D and demonstrate how our laboratories and people in the field work together to achieve continuous improvement. 

Two new MEKO free oximes for sealing and bonding

Elkem Silicones has developed two new MEKO-free oximes that feature the same performance levels as its previous products:

CAF 22 MF : a single-component translucent fast-curing RTV silicone elastomer used for bonding and sealing applications in a wide range of industries. It is particularly efficient in bonding and sealing different types of materials because its elongation/break properties allow it to withstand large differential expansion movements. 

CAF 5552 MF: a single-component non-flowing RTV silicone elastomer, specially designed for bonding and assembling metal or plastic engineering components. It is widely used in the automotive industry because of its resistance to high temperatures, chemicals and severe environmental conditions. It features, like CAF 22 MF​, excellent elongation/break properties allowing it to withstand large differential expansion movements.

Examples of some applications:

  • Sealing car engine, gearboxes, machine components and transmissions.
  • Repairing and after-market maintenance.
  • Bonding casing, beacon lights and emergency lights for extreme outdoor conditions. 
  • Bonding sliding windows, fixing aerials and electronic components, assembling heating modules, encapsulating electrical contacts, etc.​