Preparation and properties of novel ultraviolet-cured waterborne polyurethanes

Abstract

A new ultraviolet (UV)-cured waterborne polyurethane (WPU) mainly composed of ionic soft segments, imide groups, and a new water-soluble UV-cured cross-linking agent containing both C¼C bond and carboxy group was prepared. The ionic soft segments were prepared by 1,6-hexamethylene diisocyanate , poly(propylene glycol)-600, and dimethylol butanoic acid. The imide groups were introduced into polyurethane by extending them with pyromellitic dianhydride (PMDA). The new water-soluble UV-cured cross-linking agent (MLGLY) was synthesized by hydrophilic maleic anhydride and glycerol oligomer. The particle size and the viscosity of the new anionic WPU as well as the water swelling, gel content, mechanical properties, and thermal stability of the UV-cured WPU cast films were investigated. The results showed that the best performance of WPU was obtained with 0.024 mol of PMDA and 5 wt% of MLGLY.

UV-curable waterborne polyurethane coatings: A state-of-the-art and recent advances review

“…Regarding the characteristics of UV-WPU materials obtained after synthesis, it was possible to observe that their average particle sizes were 60-300 nm, except in specific cases [72,90,96,118,138]. After water evaporation, the films are photocured with a UV light incidence of 40-1000 W during photopolymerization times of 0.1-30 min, contents of up to 98 % of double bond conversion degree are obtained.…”

“…From the 138 reviewed papers, twenty-seven (27) used polytetramethylene glycol (PTMG) as polyol [26,. Polypropylene glycol (PPG) was the second most chosen polyol, being part of twenty two studies [12,23,32,40,52,59,65,[67][68][69][70][71][72][73][74][75][76][77][78][79][80][81][82], followed by poly(ethylene glycol) (PEG) (sixteen studies) [7,21,73,[83][84][85][86][87][88][89][90][91][92][93][94][95][96], poly(ε-caprolactone) (PCL) (thirteen studies) [6,20,31,52,59,[97][98][99]...…”

Synthesis, Properties, and Applications of Ion‐Containing Polyurethane Segmented Copolymers

“…As described above in relation to blood compatibility, placing functional groups on the end of ion‐containing polyurethanes can significantly impact polymer properties . Similarly, placing photoactive groups on the end of waterborne PUDs efficiently provides UV‐curable PUDs . 2‐Hydroxyethyl acrylate (HEA) and 2‐hydroxyethyl methacrylate (HEMA) are two commonly employed photoactive molecules, which readily react with isocyanate end‐groups to produce a urethane bond and upon addition of a photoinitiator and UV‐light afford UV‐crosslinked films from PUDs.…”

“…Employing the aforementioned HEMA‐endcapping strategy, Dong et al prepared UV crosslinked anionic polyurethanes. The reaction of DMBA with PPG afforded the ion‐containing SS and the addition of pyromellitic dianhydride (PMDA) into the synthesis resulted in anionic imide‐containing photocurable PUDs.…”

“…The fluorescent PUD described above is classified as an anionic PUD due to the carboxylic acid‐containing starting monomer . DMPA and 2,2‐bis(hydroxymethyl)butyric acid (DMBA) are common diols that afford anionic PUDs . Garrison et al synthesized cationic PUDs containing methoxylated soybean oil through the alkylation of N ‐methyldiethanolamine (MDEA) with acetic acid, providing ammonium cations in the backbone with carboxylate counterions.…”