Synthesis and properties of waterborne UV-curable polyurethane acrylates using functional isocyanate

ABSTRACT

For an environmentally-friendly coating, waterborne UV-curable poly-urethane acrylates were synthesized with different mixing ratios of 4,4-methylene dicyclohexyl diisocyanate (H₁₂MDI) and isocyanate-functionalized aliphatic acrylic ester (IAAE). Physical properties of the synthesized polyurethane acrylates were measured as a function of mixing ratio. Molecular structure and physical properties of the synthesized waterborne UV-curable polyurethane acrylate were investigated by FT-IR and analyzers on particle size, tensile strength, pencil hardness, and adhesion. The results showed the tensile strength and pencil hardness of the cured coatings increased with IAAE while their elongation decreased. These trends would be due to the high reactivity of IAAE which leads to high cross linking density. The optimum physical properties were obtained by controlling the mixing ratio.

KEYWORDS:

• Cross linking density
• isocyanate-functionalized aliphatic acrylic ester
• UV-curable polyurethane acrylates
• waterborne

Additional information

Funding

This work was supported by the Industry Core Technology Development Project of Research Funds of Ministry of Trade, Industry and Energy (No. 10070142) and the Korea Institute of Energy Technology Evaluation and Planning(KETEP) of the Republic of Korea (No. 20174010201460).