Preparation method and construction method of a low-viscosity thick-coated solvent-free epoxy drinking water tank paint

Abstract

The invention belongs to the technical field of epoxy drinking water tank paint, and relates to a low-viscosity thick coating solvent-free epoxy drinking water tank paint and its preparation method and construction method. The invention uses liquid epoxy resin, active diluent, pigments and fillers, Auxiliary agent and phenalkamine curing agent are components, liquid epoxy resin is bisphenol A liquid epoxy resin or / and bisphenol F liquid epoxy resin, and reactive diluent is a monofunctional reactive diluent. The components are optimized so that the final thick-coated solvent-free epoxy drinking water tank paint does not need to be diluted with additional diluents, and the dry film thickness of one-time coating is ≥300μm, and it can be quickly applied at low temperatures after construction. It is dry and avoids sagging that is easy to dry for a long time. It can also promote thick-coated coatings with excellent adhesion, chemical corrosion resistance and salt spray resistance. It can increase the service life and meet the sanitation requirements of drinking water. The requirements for indicators and toxicological indicators have positive significance.

Description

technical field [0001] The invention relates to a paint type paint, in particular to a food-grade drinking water tank inner wall anti-corrosion paint, which is suitable for ship drinking water tanks, ballast water tanks, drinking water storage tanks, drinking water tanks, inner walls of drinking water pipelines, etc. The formulation of epoxy coating for anti-corrosion protection and its preparation method and construction method. Background technique [0002] The world economy is developing rapidly, and industries such as shipbuilding are also developing rapidly. In order to keep up with the modern concept of environmental protection and green, product technology must be upgraded as soon as possible. A ship is a special means of transportation that sails in various sea areas around the world. It is subjected to a marine climate and corrosive environment that is many times harsher than that of land. Moreover, due to its different structures and functions, the functionality of...

AI Technical Summary

Problems solved by technology

The cabin can be classified as a confined space. General solvent-based coatings are applied in a confined space. If there is no effective ventilation, the volatilization of organic solvents will easily cause safety production accidents.

In the short term, the organic solvent in the paint film cannot be completely volatilized, and the residual organic solvent will also have a certain adverse effect on the performance of the paint film and the water quality after water pressure

[0005] 2) One-time thick coating is prone to sag problem

Solvent-free paints are very slow to surface dry, and generally take more than 2 hours to dry to the surface. During this time, the one-time thick paint is easy to sag without drying for a long time;

[0006] 3) The viscosity is high, so it cannot be applied directly

It is often necessary to add diluent for proper dilution during construction, which cannot achieve low VOC emission standards;

[0007] 4) The problem of inability to construct under low temperature and high humidity environment

Generally, the curing reaction speed of high-solid and solvent-free epoxy coatings is too slow at low temperature or the paint film is prone to oil surface phenomenon under high humidity conditions, which causes problems of sticking back and interlayer adhesion.

The temperature is low and the humidity is high, usually auxiliary heating equipment or dehumidification equipment is required, which consumes a lot of manpower and material resources

Slow curing reaction and sticking back will also affect the appearance quality of the film under low temperature and high humidity, causing problems such as poor water quality after water pressure, yellowing of the paint film, and inability to recoat, and interlayer adhesion problems that cannot be recoated will affect Late repair and touch-up problems, resulting in overcoat peeling

[0008] At present, in order to solve the problem that the solvent-free epoxy drinking water tank coating is applied at low temperature in winter, the viscosity increases sharply, the reaction speed is slow, and the hardening time is long, so it is difficult to adapt to the actual coating process requirements.

In the Chinese patent CN201010616731.0 low-temperature quick-drying solvent-free epoxy drinking water tank coating and its preparation method, what is added is a tertiary amine catalyst K-54 and a curing agent to react together, although the reactivity and hardening and drying speed of the coating are improved, but the time is greatly shortened. The activation period is shortened, which increases the difficulty of actual construction

CN201310416385.5 A fast-curing environment-friendly epoxy coating for drilling water tanks and its manufacturing method. Although it is a solvent-free epoxy, it contains zinc chrome yellow, which does not meet the drinking water hygienic and toxicological indicators, and has not been studied Drying and curing conditions in the thick coating state, and its salt spray resistance is also difficult to meet the requirements of the naval coating performance specification of not less than 2000h

[0009] In view of the fact that the existing solvent-free epoxy drinking water tank paint cannot meet the requirements of direct construction without diluent, the VOC emission is difficult to be lower than 100g / L, the dry film thickness of one-time construction is less than 300 microns, and the low temperature and high humidity cannot be applied. Problems such as direct recoating without sanding

Images