Non-hazardous water-based polyurethane dispersion

A method comprising:

• introducing a coalescent comprising 2,5,7,10-tetraoxaundecane into a water-based polyurethane dispersion such that the 2,5,7,10-tetraoxaundecane is present in the water-based polyurethane dispersion in an amount of 10% to 40% by weight based on the total weight of a chain-extended polyurethane in the water-based polyurethane dispersion;
• applying the water-based polyurethane dispersion to a surface of a plastic substrate or a rubber substrate to coat the plastic substrate or the rubber substrate such that a thickness of the coating is in the range of 50 microns to 3 mm, wherein the water-based polyurethane dispersion is applied to the plastic substrate or the rubber substrate at a temperature below 30° C.;
• and
• forming a film at a temperature below 30° C. on the plastic substrate or the rubber substrate by evaporation of water of the applied water-based polyurethane dispersion,
• wherein the water-based polyurethane dispersion is a rigid polyurethane dispersion, and
• wherein the rigid polyurethane dispersion is based on an isocyanate-terminated polyurethane prepolymer that is a reaction product of:
• (i) a polyester polyol and/or a polycarbonate polyol, (ii) dimethylol propionic acid (DMPA), and (iii) bis(4-isocyanatocyclohexyl) methane, and is chain extended by a polyamine.