Low Free monomer, High NCO and functionality

LANXESS Urethane Systems drives development of powerful low monomer prepolymers used as flexible formulation platform for adhesives and sealants and one component foams. Prepolymers enable unique adhesive formulations designed for target applications. LANXESS offers full low monomer approach for flexible and customized “label-free” adhesives and sealants, especially important for reactive hot melts. Our ability to tailor the properties of the LF prepolymer to the needs of the application allows the generation of a fully flexible formulation platform which provides:

• Reduced complexity
• Improved industrial hygiene by avoiding handling of free monomeric isocyanate during formulation and final use
• Broad toolbox of LF prepolymers with ether or ester based prepolymers with a wide range of NCO content (up to 10%)
• Use of 4,4’MDI or 2,4 & 4,4’ mixed MDI prepolymers for tailored reactivity
• Storage stability of Adiprene^® LF prepolymers with <0.1wt% free diisocyanate monomer

LF (Low Free) monomer technology

The innovative LF (Low Free) monomer technology creates prepolymers with less than 0.1 wt.% free diisocyanate content for excellent adhesive performance, improved processing and unsurpassed industrial hygiene.

Adiprene^® LF prepolymers have a highly structured morphology to provide superior adhesive performance, including excellent toughness, fatigue resistance, and longer lifetimes when exposed to extreme conditions of temperature and chemicals. This is achieved through a narrow molecular weight distribution, virtual crosslinking, and more defined phase segregation as these define the structure-property relationships in PU adhesives.

The phase segregation morphology between hard and soft segments is driven by the degree of order within the hard segment. This is governed by the chemical structure and concentration of both isocyanate and curing agent as well as the chemical structure and molecular weight of the polyol. The LANXESS prepolymer approach drives controlled morphology and allows enhanced phase segregation of the hard and soft segment domains, thus enabling the creation of high performance materials.

LF technology offers environmental, health and safety benefits as it protects workers from potential exposure to free isocyanate and allows the formulation of products with a lower hazard classification (below 0.1 wt.% free diisocyanate content). Learn more about LF Technology. 

High NCO and higher functionality

These advanced functionality prepolymers with customized properties in terms of reactivity, NCO content (up to 10%) and viscosity lead to improved crosslinking and increased strength and rigidity in adhesive formulations. A high NCO content of up to 10% can lead to adhesives with improved physical and mechanical properties while highly crosslinked systems result in increased strength and rigidity for the application in demanding environments. The tight control of viscosity achieves lower viscosity at working temperature for improved processing consistency.

Through this technology, a flexible formulation platform is created which can be used in a diverse range of high performance adhesives and sealant applications, across industrial markets including construction, automotive, electrical and packaging.

The deep expertise in designing a wide range of urethane prepolymers for adhesive systems and associated formulation knowledge qualify LANXESS Urethane Systems as the ideal choice for adhesive formulators.

Adiprene^® LF Portfolio