Corrosion-resistant epoxy powder coating has many changes

Epoxy powder coating, a "green coating" containing 100% solid components, with its excellent adhesion, flexibility, as well as excellent corrosion resistance and corrosion-resistant life, by the anti-corrosion coating industry personnel of all ages; Recently, the School of Materials Science and Engineering of Beijing University of Chemical Engineering modified the epoxy resin system to improve its physical and mechanical properties and chemical resistance. According to
China Coatings Onlineexperts
, in order to improve the epoxy powder coating system water resistance and corrosion resistance, they added rare earth phenols to the epoxy resin modified. Using infrared, DSC, GPC and other test methods, the powder coating was studied, and it was found that the water resistance and corrosion resistance of the modified powder coating system were significantly improved, and its storage performance and mechanical strength were also significantly improved, indicating that this method is feasible. The reagent materials tested include epoxy resin (E-20), Blue Star new material Wuxi Resin Plant, double cyanide, Beijing Chemical Reagent Company, silicone smoother (UC 338B), Pinghu City United Chemicals Co., Ltd.; titanium white powder (sharp titanium type) Beijing Chemical Reagents Co., Ltd.; Ultra-high molecular polyethylene, Beijing Additive II Plant; 2-Methyl Mimi, ACROS ORGANICS; Phenolic resin, Beijing University of Chemical Engineering; Coupled Agent, Nanjing Shuguang Chemical Plant; Rare Earth Chloride, China Nonferrous Metals Research Institute.
researchers first carried out epoxy powder coating preparation, in the preparation of epoxy powder coating, in order to make the raw material mix more uniform in the experimental process, first of all, the raw material used before use roughly crushed to 50 mesh, and then proportionally weighed raw materials, mixed evenly and after 70 to 80 degrees C melt mixed 20min, cooled to room temperature and then crushed to 180 mesh, that is, to obtain the finished product backup. Tests include powder coating performance testing and powder coating performance testing. Through orthoding testing and extremely poor analysis, the researchers tested the appearance, hardness, impact strength and chemical resistance of the coating to arrive at the formula of epoxy powder coating system - epoxy resin (E-20) 100, filler (titanium dioxide)3 0, toughener (ultra-high molecular polyethylene) 3, curing agent (double cyanide) 4, curing promoter (2-methylamine) 0.5, leveling agent (silicon smoother) 0.5. Paint properties made from this formula - appearance (visual): same color, no lumps; average granularity (standard sieve): 180 mesh; glue time (GB/T 6554-2003): 150s (200%). Epoxy powder coating performance test results - appearance (visual): smooth and flat surface, impact resistance (GB/T 1732-1993)/cm:50; hardness (GB/T 6739-2006): 4H; chemical resistance (10% NaCl solution, GB/T18593-200) 1): The coating is free of foaming, cracking, peeling, etc.; salt spray test (GB/T 1771-1991): the coating is free of foaming, cracking, peeling, etc.; adhesion (grade, SY/T 0315-2005): 2; bending strength (GB/T 6742-1986)/mm:5. the main instruments and equipment of
experiment are, DF204 type electric blower drying box, FW10 type high-speed all-purpose shredder, standard sieve (50 mesh, 180 mesh), SK-1608 type double roller cylinder molding machine, DSC differential thermal analyzer, QCJ type lacquer film impactor, SFP-80 type electrostectant spraying equipment. The researchers studied the modified epoxy substate. Including phenolic modified epoxy resin, add phenolic resin to the epoxy resin substate for alteration, so that 2 kinds of resin active functional inter-group cross-linking reaction, the resulting modified coating film has both strong adhesion of epoxy, flexibility, good alkaline resistance advantages, but also with phenolic resin water resistance, solvent resistance and excellent acid resistance characteristics. Subsequently, the performance of rare earth phenolic resin and its coating improved, because rare earth elements are generally prone to lose 3 electrons, positive price, its reaction activity is very high to participate in the reaction of high active agent, but also its own catalyst; Finally, the storage stability of rare earth phenolic modified epoxy powder coating was studied, and the coating performance of rare earth phenol aldehyde modified did not change much, indicating that the storage stability performance after the modified was significantly improved. Phenol-modified epoxy powder coating due to the co-conjugation reaction of 2 resins, increased the cross-linking density of the system, improved the coating film resistance to media penetration, make up for the deficiency of epoxy resin in this regard;
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