Coreactants for polyurea coatings
A method to accelerate cure of a multicomponent coating composition is described herein, including the steps of providing an isocyanate and an isocyanate-reactive compound, and replacing a portion of the isocyanate-reactive compound with a compound of formula I:
1. A method to accelerate cure of a polyurea coating, comprising:
providing a first component including an isocyanate-functional component;
providing a second component including a polyaaspartic ester as an isocyanate-reactive component;
providing a coreactant component comprising tri-butyl citrate, wherein the tri-butyl citrate comprises up to 20% of the isocyanate-reactive component; and
combining the isocyanate-functional component, the isocyanate-reactive component and the coreactant to produce a polyurea coating composition with accelerated cure and mixed viscosity (Gardner) of about A-1 to A-2.
2. The method of claim 1 , wherein combining the isocyanate-functional component, the isocyanate-reactive component and the coreactant component comprises
combining the the coreactant component with the isocyanate-reactive component to form a mixture; and
combining the mixture with the isocyanate-functional component.
3. The method of claim 1 , wherein combining the isocyanate-functional component, the isocyanate-reactive component and the the coreactant component comprises
making the isocyanate-reactive component in the presence of the;
coreactant and
combining the isocyanate-reactive component with the isocyanate-functional component.
4. The method of claim 1 , wherein the isocyanate-reactive compound and the polyisocyanate are reacted together at NH:NCO ratio of 0.8:1.0 to 1.5:1.0.
5. The method of claim 1 , wherein the isocyanate-reactive compound and the isocyanate-functional compound are reacted together at NH:NCO ratio of 0.8:1.0 to 1.2:1.0.
6. The method of claim 1 , wherein the isocyanate-reactive compound and the isocyanate-functional compound are reacted together at NH:NCO ratio of 1.05:1.0.
7. The method of claim 1 , wherein the coreactant is about 5% to up to 20% based on the total weight of the coreactant and isocyanate reactive compounds.