Polyurethane dispersion based on 2,2'-MDI

摘要

Polyurethane coatings are capable of providing a high level of performance. For coatings that are subject to high mechanical stress, polyurethanes based on aromatic polyisocyanates are particularly valuable. One of the disadvantages of aqueous polyurethane dispersions made from aromatic isocyanates is limited storage stability. Earlier patents describing polyurethane dispersions containing 2,4'-diphenylmethane diisocyanate and diphenyl 4,4'-diisocyanate report unwanted coagulum and inadequate storage stability.