In August 2020 the European law was enforced, requiring professional construction and industrial users of products containing more than 0.1% of free monomeric diisocyanates to be trained on the risks associated with working with diisocyanates and the corresponding risk management measures required.
Many professional users, especially trades- and craftsmen, that use sealants and adhesives only as process materials, will not be aware or eager to do such a training. Alternative solutions for their applications, apart from foams are readily available with silane terminated polymers (STP), and silicones products. Recently there are also polyurethane sealants, adhesives and foams available on the market with monomeric diisocyanate contents below 0.1% and therefore not affected by the European PU restriction regulation.
Beside this ultra-low monomer content with these very defined polymers improvements of the product properties can be achieved. This leads to several advantages like easier extrudability over a wide temperature range, rapid build-up of mechanical properties, advanced resistance to hot and humid conditions, non-staining properties on natural stones and environmental stress cracking with thermoplastics. Several examples of these improved properties will be shown.