Researchers at Tianjin University, School of Chemical Engineering and Technology, have studied the molecular structure of UV curable waterborne polyurethane acrylate (UV-WPUA) emulsions. The investigation showed in particular three outstanding properties.
Preparation of UV-curable waterborne polyurethane-acrylate emulsions. Source: pixabay.com
Polyurethane acrylate oligomer terminated with multiple unsaturated bonds was prepared using isophorone diisocyanate (IPDI), methylene diphenyl diisocyanate (MDI), and polyols as monomers, using 2,2-dimethylol propionic acid (DMPA) as hydrophilic chain extender, together with pentaerythritol triacrylate (PETA) as end-capper.
The UV curable waterborne polyurethane acrylate (UV-WPUA) composite emulsion was obtained by mixing the PUA oligomer with certain content of reactive diluents and then dispersing the mixture in water. The molecular structure of the polyurethane prepolymer, PUA oligomer, and UV-cured polymer was investigated by FT-IR. The influence of the composition and content of the diluents and end-capper on UV-WPUA properties, including the emulsion stability, thermal property, water resistance, adhesion, hardness, glossiness of polymer film were studied. The results showed that the WPUA emulsion has excellent stability, and the UV-cured film features good hardness and remarkable water resistance when PETA is used as end-capper and the end-capping ratio of the polyurethane prepolymer is 70% and DPHA/DPGDA (mass ratio 1:1) is used as diluent.
The study is published in: Journal of Applied Polymer Science.
What are paints and coatings composed of? This efficient reference book offers an optimum overview of the different constituents of the different types of coatings, explaining the chemistry, system and impacts of coating raw materials. That way, newcomers to the field of coatings gain a quick basic knowledge whereas chemists and laboratory assistants will find valuable insights on future trends and developments in the field of raw materials.
You are currently not logged in
To leave a comment, please log in.
There was an error while sending your comment. Please try again.
Your comment was too long. There are a maximum of 2048 symbols allowed!