Properties / Applications: Effective mechanical stirring is needed to emulsify Desmodur® DA-L in the adhesive dispersion. Stirring by hand is not sufficient for good homogenization, especially with low-viscosity adhesive dispersions. Inadequate dispersion can lead to granular separation from the adhesive mixture. After adding the Desmodur® DA-L, the ready-to-use two-component adhesive must be used within its pot life, which is governed not only by its polymer content but also by its other components (resin, thickener, plasticizer etc.). With many dispersions, the end of this pot life – which generally lasts several hours – does not become evident through gelling. It can be determined by measuring the strength properties of the bonds, particularly the heat and water resistance. An addition of 3 - 10 % by weight Desmodur® DA-L is recommended for crosslinking 100 pbw of an adhesive dispersion with a polymer content of 40 – 60 % by weight. Desmodur® DA-L is generally processed without further additives. Should Desmodur® DA-L nonetheless be modified with an additive, this may contain no groups which react with isocyanate and no secondary components which may do so. In particular, any additives used must be free of secondary components which are alkaline or have a catalytic effect on isocyanate groups. l Even at a very low concentration these can cause an increase in viscosity or even solidification.

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