Properties / Applications: To ensure the optimum distribution of Desmodur® DN, the adhesive dispersion must be stirred well by mechanical means. Manual stirring is not sufficient to ensure good homogenisation, especially in the case of low-viscosity adhesive dispersions. Inadequate dispersion may result in the formation of granular deposits in the adhesive. After addition of Desmodur® DN, the ready-to-use two-component adhesive must be used within the pot life. This is governed not only by the polymer content but also by the other constituents (resin, thickener, plasticiser, etc.). The end of the pot life – usually several hours – is not always marked by gelling. It can be established by determining the resistance properties of the bonds, above all the resistance to heat and water. An addition of 3 - 10 % by wt. Desmodur® DN is recommended to crosslink 100 pbw of an adhesive dispersion with a polymer content of 40 - 60 % by wt. Desmodur® DN is generally processed without further additives. Should Desmodur® DN 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. Even at a very low concentration these can cause an increase in viscosity or even solidification.

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