International. Indian researchers at National Chemical Laboratory have developed flexible novolaca epoxy coatings with two different cardanol-based flexers that show great potential in industrial applications.
The coatings were developed by reacting a novolaca epoxy resin, poly [(phenylglycidyl ether)-coformaldehyde] (PPGEF) with an amine curing agent, 4,4'-diamino-3,3'-dimethyldicyclohexyl methane (BMCHA), cardanol base reactive diluent (Cardolite NC-513) and two different cardanol base flexibilizers (Cardolite NC-514 and Cardolite NC-547). The content of the flexibilizer ranged from 5 to 10% by weight of the resin.
The coatings were coated on stainless steel panels and tested to determine the gloss, adhesion of the cross-hatches, impact resistance of downward weight, flexibility, abrasion, scratch hardness, solvent washing resistance and chemical resistance.
Thermo-mechanical properties were determined by measurements of TGA, DSC, DMTA and tensile strength. The cryocratured specimens underwent SEM analysis. The influence of the structural differences of the two flexibilizers on the coating properties was investigated.
The study can be viewed by clicking here.
Leave your comment