Coating used for steel bars, as well as preparation method and use method

Abstract

The invention discloses a coating used for steel bars, which includes: epoxy resin A, of which the epoxide equivalent is 1500-1800 and addition amount is 30-60%; epoxy resin B, of which the epoxide equivalent is 750-850 and addition amount is 10-20%; a phenol curing agent, of which the hydroxyl equivalent is 300-450 and addition amount is 8-20%; epoxy adduct imidazole, addition amount being 1-3%;a flatting agent, addition amount being 0.5-2%; filler, addition amount being 10-20%; and a pigment, addition amount being 3-8%. In the epoxy resin, the curing reaction is mainly on the epoxy group, which is influenced by the ether bond and a large Pi bond on the benzene ring, so that electron cloud distribution has a large deviation, which generates a dipole moment; therefore, the oxygen atoms onthe epoxy groups carry a large number of negative charges, whereas the carbon atoms, on the terminal, hold a large number of positive charges; as a result, both an electrophilic reagent and a nucleophilic reagent enable ring-opening polymerization of the epoxy group in an addition reaction manner, thereby finally forming the polymer having the network structure.

Description

technical field [0001] The invention relates to a formula, a preparation method and a use method of a paint for steel bars, in particular to a paint for steel bars, a preparation method and a use method. Background technique [0002] Rebar is an indispensable building material for various construction projects. In coastal port terminals, sea-crossing bridges, buildings using reinforced concrete or airports and highways that need to be sprayed with salt water to remove ice and snow, some gaps or gaps will inevitably appear in the reinforced concrete. When exposed to salt water or Corrosion of steel bars in reinforced concrete will be caused by acid rain and other corrosion. The oxide scale produced by corrosion expands dozens of times in volume, leading to concrete cracking and peeling off of the protective layer, so that the steel bars are directly exposed to the atmosphere, water and its corrosive media, the corrosion speed is accelerated, and the buildings are often destr...

AI Technical Summary

Problems solved by technology

[0003] At present, coatings for steel bars use a single type of epoxy resin as the main component, which has problems such as too long molecular chain, too high viscosity, poor leveling, poor wettability with the substrate, and bending cracking; in addition, there is a technical problem, That is, the curing agent selected in the coating for steel bars is inconsistent with the type of epoxy resin, or the curing agent chain segment is too short, not flexible enough, and it is easy to bend and crack; or the curing agent chain segment is too long, and the wetting of the coating and the substrate Poor performance, adhesion problems

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