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Monomeric isocyanates for the production of prepolymers
Prepolymers terminated with isocyanate groups and based on the two
Bayer adhesive raw materials Desmodur® and Mondur® (here the monomeric
isocyanates) and Bayer's polyols form the basis for one-component
adhesives. Desmodur® I and W and Mondur® M and TD-80 are used as the
co-reactants for solvent-free (and solventborne) adhesives.
Properties: Depending on the grade of polyol, the
products are either liquid, amorphous or crystalline at room temperature.
Moisture leads to the curing of these systems, with urea structures
forming to give the bonds high strength and good heat resistance.
The aromatic-based prepolymers have high reactivity, good structural
strength and a tendency to discoloration from yellow to brown on exposure
to light. Aliphatic systems, on the other hand, are characterized
by low reactivity, lower strength and discoloration resistance.
Uses: In the packaging industry, monomeric diisocyanates
are used above all for the formulation of adhesives for the manufacture
of composite film for food packaging.
Advantages:
- outstanding cohesion and adhesion
- very good heat resistance
- resistance to plasticizers and grease
- rapid crosslinking
- aromatic-based prepolymers are noted for their high reactivity
and good structural strength
- aliphatic-based prepolymers are noted for their good light stability
Contact us and
our technical experts will be pleased to give detailed advice on the
applications and formulation of adhesives based on DesmodurĘ and MondurĘ.
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