Time：2018/9/14 Check：24
(1) of hyperbranched polyester applications in high solid coatings
Molecular structure is compact, with three-dimensional spherical structure, and not easy entanglement between molecules, compared with the same molecular weight linear polymers, its solution in high solid content, there are still relatively low solution viscosity.
Example 1:
Oleic acid modified hyperbranched polyester with beans, hyperbranched alkyd, cadmium salt, in the presence of cobalt salt and calcium salt, dry (23 + 2) ℃ respectively, 5, 8 and 24 h, the determination of rocker hardness, Beck - immersing recorder is used to test the drying time, get the dry film thickness for 35 + 5 microns. Just like ordinary alkyd resin, can be different oil alkyd resin, used in room temperature dry or paint.
(2) of hyperbranched polyester in the application of UV curing coating
Will be introduced to the UV curing system of hyperbranched polymer, can overcome some disadvantages linear oligomer and severe contraction, thinner, volatilization, such as film is toxic, etc.
Thermosetting type hyperbranched hydroxyl end group of polyester, can through the introduction of inactive/active end group to control the crosslink density.
With propylene acylation polyester used for UV curing coating, don't need to add light initiator, under the low intensity of UV irradiation, can be solidified into a film, film hardness, resistance to acetone wipes and scratch resistance is better.
Example 1
With acryloyl chloride with dihydroxy methyl propionic acid as monomer synthesis of hyperbranched polyester base modification to end, won the ultraviolet curing coatings.
Example 2
Tang Liming method of synthesis and purification of Johansson is improved, the maleic anhydride directly into the reaction system, the end based on the initial polymer modification, obtained the excellent comprehensive performance without solvent uv-curing coatings
(3) of hyperbranched polyester in the application of powder coatings
Powder coating is high curing temperature, large energy consumption, and heat sensitive substrate can't construction application.
By introducing can overcome the shortcomings of hyperbranched polymer.
General powder coating of the curing time is 10 ~ 30 min, the temperature is 170 ~ 200 ℃, this limits the powder coating in the film base material or the application of heat sensitive substrate.
And UV curing powder coatings made up for the shortcomings, can be used for heat sensitive substrate, low temperature curing, good liquidity, curing speed, etc.
