The waterborne urethane acrylate contains a large amount of reactive groups to impart good flexibility and cohesiveness to the cured film, but at the same time, mechanical properties, solvent resistance and water resistance are reduced.

To overcome these shortcomings, studies have found that the introduction of fluorine-containing segments can improve this situation very well.

Fu Jianping and others use polyurethane (PU) emulsion, sodium ethylenediamine sulfonate (AAS) as chain extender, butyl acrylate (BA), perfluorooctyl ethyl acrylate (FA), methacrylate The ester (MMA) is a monomer, and an aqueous fluorine-containing urethane acrylate (WFPUA) composite emulsion is prepared.

Studies have shown that the introduction of organic fluorine monomer FA and the chain extension of AAS can effectively improve the crosslinking degree of the polymer, and at the same time improve the stability of the emulsion and the water resistance of the film.

Yingfei et al. use hexamethylene diisocyanate (HDI) trimer, hydroxyethyl methacrylate (HEMA), 1,6-hexanediol (HDO), 1 H, 1 H, 2 H, 2 H- Fluorinated urethane acrylate (FPUA) was synthesized from trifluoro-1-octyl alcohol (TFOA).

Studies have shown that the introduction of fluorine improves the hydrophobic antifouling properties, compatibility, mechanical properties and curing rate of the cured film.

Li Peizhi et al. prepared polyurethane (PU) using toluene diisocyanate (TDI), polyester diol (PE1000), trimethylolpropane (TMP), and N-methyldiethanolamine (MDEA) as raw materials.

The cationic perfluorourethane acrylate was prepared by solution polymerization using butyl acrylate (BA), styrene (St) and perfluoro acrylate (FA) as monomers and azobisisobutyronitrile (Al BN) as initiator. polymer.
   
Studies have shown that the surface of the fabric treated with cationic perfluorourethane acrylate polymer has improved contact angle between water and paraffin oil, which enhances its antifouling performance.

2.3 Powder type urethane acrylate
UV-cured powder coatings combine traditional powder coatings with UV curing technology. The most typical feature is that the curing process is divided into two distinct stages, and the early curing of the resin does not occur during the melt-leveling phase of the coating.

Thereby providing sufficient time for the coating to fully advect and repel the bubble operation, fundamentally overcome the shortcomings of the thermosetting powder coating, and also make up for the deficiency of the UV curing liquid coating.

UV-curable powder PUA coating has the advantages of no VOC emission, high utilization rate of raw materials, low temperature curing, and high production efficiency.

A Wenning et al. squeezed and urethane acrylate at 120~130 °C, cooled to the greenhouse, and after proper pulverization, electrostatically sprayed onto a suitable substrate to prepare a powder coating with good adhesion.

HUANG Wei et al. modified aromatic toluene diisocyanate (TDI), octadecyl isocyanate, hydroxyethyl acrylate (HEA) and hydroxylated dendritic polyether diamide to synthesize different concentrations of acrylate and long Semi-crystalline polymers of the chain alkyl groups DPEA-A and DPEA-B.

Its Tg is 45 ° C and 41 ° C, respectively, Tm is 123 ° C and 122 ° C, suitable for UV-curable powder coatings, its UV-curable film has excellent chemical resistance, weather resistance, scratch resistance and excellent mechanics performance.

UV-curable powder coatings have many advantages, but achieving low-temperature curing is not an easy task. It requires raw materials to impart good storage stability to the powder, the powder has a lower melt viscosity at lower temperatures, and the glass transition temperature of the resin, Both molecular weight and molecular weight distribution have specific requirements that limit the development of UV powder coatings.