A multinational company, active in the manufacture of 1K aromatic polyurethane sealants used in the construction sector.
The company had developed a range of 1K aromatic polyurethane construction sealants, however, the formulations offered poor storage stability and bubbling due to the evolution of CO2.
As a result, the sealants exhibited poor durability and delamination from the concrete substrate.
The company shared information on their existing formulation and related shortcomings. Incorez’s application team proposed the use of Aldirez BH aldimine latent curing agent technology to resolve the problem. The customer had limited experience of formulating with aldimine technology and received extensive formulation support to find a solution.
By using Aldirez BH as a latent curing agent, the company was able to formulate a range of low to medium modulus construction sealants for applications such as floor movement joints and façade joints.
Aldirez BH can be used in a range of 1K aromatic moisture triggered polyurethane sealants. The technology lends itself to low and medium modulus construction sealants.
In a traditional moisture cure reaction, moisture reacts directly with the terminal isocyanate of the prepolymer, generating carbon dioxide. In a moisture triggered system, moisture reacts preferentially with the Aldirez BH aldimine rather than with the prepolymer’s terminal isocyanate groups.
This technology avoids the generation of carbon dioxide, enabling bubble free curing at elevated temperatures and humidity levels. The product also gives excellent storage stability with aromatic prepolymers, low crystallisation stability and improved shelf life.
The addition of Aldirez BH in the company’s formulation provided the customer with a stable, durable product.