Polyamidoamine (PAMAM) dendrimer application in Coatings
Characteristics of dendritic PAMAM:
(1) Good hydrodynamics performance
(2) Unique viscosity behavior, has promising application prospects in coatings.
(3) Easy to forming-film, has promising application prospects in coatings.
(4) Having a large number of active surface group, so functionalized and modified end group is more convenient.
(5) A highly branched molecular structure determines its less prone to crystallization
(6) Having a good thermal stability
Application Example 1
Using half-generation dendrimer as a seed, styrene as the representative monomer to mix emulsion. The resulting average particle size of the polymer emulsion of ions between the 30-50nm, less than 100nm, and even distribution;
Dendrimers with amino terminal group graft the silicon obtained epoxy curing agent, and uniformly dispersed in the epoxy resin, showed that the elastic modulus of cured material is lower than commonly used curing agent, and the heat resistance is improved.
Using Dendrimers with amino terminal group as the epoxy resin curing agent, adding the theoretical amount and without diluent, at 20 ℃, usage time and gel time of such coatings are 6.0 and 2.4 times than ethylenediamine/epoxy System. And curing at 95 ℃, 120 ℃, 150 ℃, curing speed are 1.8 times, 3.4 times and 4.8 times than ethylenediamine/epoxy resin system.
Dendrimers with amino terminal used as curing agent for the epoxy resin, at different temperatures and concentrations , the results shows that the gel time can be reduced under high temperature and reaction rate and kinetic constants are increased. The activation energy is significantly higher than the activation energy after the gel point.
PAMAM Dendrimers have low melt viscosity, good compatibility and plentiful end group which can be modified, and it can be applied for coating system. Liang Hongbo etc. has reported on the polyamidoamine dendrimer modified end groups that by the introduction of crystallizable segments, can obtain semi-solid, semi-crystalline polymers which may be used as UV-curable powder coatings. This coating is solvent free, no VOC emissions, and has good raw material utilization, easy to operate. Weihai CY Dendrimer Technology Co. Ltd.-Professional Manufacturer for low cost dendritic polymers.