At the recent FEICA European Adhesive & Sealant Conference and Expo, LANXESS highlighted its latest developments in low free (LF) isocyanate urethane systems for adhesives, sealants, and one-component foams (OCF). The company’s Adiprene LF technology reportedly creates prepolymers with < 0.1 wt% free MDI (methylene diphenyl diisocyanate) and other isocyanates such as TDI (toluene diisocyanate), HDI (hexamethylene diisocyanate), or pPDI (p-phenylene diisocyanate), providing industrial hygiene standards, excellent performance, and improved processing. According to the company, these prepolymers are particularly suited to address increasingly strict regulatory requirements and provide for final products with lower hazard classifications.

LANXESS reports that its toolbox of Adiprene LF prepolymers is able to tailor the reactivity, viscosity, and polyol backbone of the prepolymer to adjust it to the needs of formulators. By controlling the chemical structure, these prepolymers reportedly have a very structured morphology to offer more consistent processing.

On the third day of the conference, Ronald M. Emanuel Jr., senior scientist, Global Research and Development, Adhesives, spoke about “Advancements in low free isocyanate monomer prepolymer design for reactive adhesive systems.” The presentation reportedly provided insight into LF isocyanate prepolymer chemistry.

“The focus of our development work is to design prepolymers containing low free monomer content for use in adhesive and sealants formulations,” said Emanuel. “In particular, this refers to overcoming the differences that the removal of residual diisocyanate monomer present to the performance of the final adhesive formulation.”

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