Preparation method for anti-cathodic-disbonding powder coatings

Abstract

The invention discloses a preparation method for anti-cathodic-disbonding powder coatings. The method comprises the steps of adding 65 parts of epoxy resin, 45 parts of novolac epoxy resin, 26 parts of polyester resin, 1.5 parts of curing agents, 8 parts of carbon black, 3 parts of barium sulfate, 0.3 part of preservatives, 1 part of antioxygen 168, 0.5 part of leveling agents, 4.5 parts of titanium dioxide, 3 parts of benzoin, 6 parts of mica powder, 2.5 parts of zinc borate and 7.5 parts of antimonous oxide into a high-speed mixer to be mixed uniformly sufficiently; performing melt extrusion on the mixture through an extruder, pulverizing extruded sheets in a pulverizer to be screened and packaged into products. According to the method, the epoxy resin, the polyester resin and the curing agents are selected and have a coordination effect; the preservatives are selected, so that the coating anti-corrosion performance is improved; the zinc borate and the antimonous oxide are used as flame retardant, so that the coating has an outstanding high temperature resistance performance, and an outstanding anti-cathodic disbanding property is provided at the high temperature.

Description

technical field [0001] The invention belongs to the technical field of coatings, in particular to a preparation method of a high-temperature-resistant and anti-cathode stripping powder coating. Background technique [0002] In order to ensure the long-term reliable operation of buried metal pipelines in harsh environments, in addition to using thick-coated epoxy powder coatings with good anti-corrosion effects for protection, a polyethylene protective layer with high mechanical strength is added to minimize mechanical damage that may occur during transportation and construction. In addition, cathodic protection is also used. However, in an electrochemical corrosion environment, if the coating has low cathodic stripping resistance, the coating will degrade and crack, and lose its anti-corrosion effect. The electrochemical corrosion rate under cathodic protection conditions has a great relationship with the temperature environment used. The higher the temperature, the faster ...

AI Technical Summary

Problems solved by technology

However, in an electrochemical corrosion environment, if the coating has low cathodic stripping resistance, the coating will degrade and crack, and lose its anti-corrosion effect.

The electrochemical corrosion rate under cathodic protection conditions has a great relationship with the temperature environment used. The higher the temperature, the faster the corrosion rate. Therefore, the ability of the coating to resist cathodic stripping needs to be durable at high temperatures. In this way, the original powder coating Whether it is single-layer or three-layer powder coating, it is far from meeting the requirements