Coating leveling mechanism and the use of leveling agents

The addition of leveling agents affects the appearance of the coating film, interlayer adhesion and recoatability. Conventional leveling agents include acrylic copolymers, silicones and fluorocarbon surfactants. Homopolymers and copolymers with methacrylates as monomers are often used as leveling agents, controlling their degree of incompatibility with the base resin to provide a leveling effect.

The choice of different monomers, control the average molecular weight and modified with different functional groups can change the leveling effect. Silicone leveling agents have low surface tension, high surface activity, because silicones can be enriched on the surface of a large number of methyl groups. The new generation of silicone leveling agent commonly used polyether modified, polyester modified or alkyl modified. In addition, can also be adjusted by adjusting the molecular weight and silicon content to achieve the purpose of adjusting the leveling agent performance. Fluorocarbon leveling agent is the more effective of all leveling agents to reduce the surface tension, but there is a recoating easy to blister the disadvantage.

Toluene Mitsubishi only, grade: TW304B molecular weight: CrH&N: Na relative molecular weight: 155.14 sodium salt is a kind of steel and steel appearance: light yellow particles into alloys, its powder freezing point: -8 ℃ content: * 99.0 % Moisture: ≤0.5% Ash: ≤0.2% Oxide: 50mg/kg Packaging and storage: This product is packed in a 25kg plastic drum into a 200kg iron-plastic drum.

Amines and amine salts
Amines and amine carboxylates are well known as steel corrosion inhibitors, but synthetic paraffin safe they are much later used as corrosion inhibitors for coatings. The adsorption of carboxylates on iron is complicated because of several forms. The adsorption is mixed together, and they include the anion and cation of the salt, the association product, or the coordination compound produced by it. Sz auer and Brandt in the United States discussed the adsorption of iron by various amines. In US Patent No. 4, 131, 583 (1978), Boer Winkle proposed a salt of carboxylic acid and organic amine for use in water-based coatings. Can improve the corrosion resistance of metals.

A proprietary amine product of Ray bo Chemical Co. under the trade name Raybo85Rustib. It is a cationic wetting agent that can be adsorbed on the surface of steel and oriented as a monomolecular film on the interface between the coating and the metal. . Paints containing such products can be applied to wet surfaces, and can improve the problem of paint precipitation caused by poor wetting. Add 0.5% Raybo85Rustib to the iron alkyd red workshop primer and apply it to the steel plate for salt spray test. The modified primer can pass 100h, but the modified primer fails for 50h. This type of product can be used in both water-based and oil-based coatings. It is mainly used in ethylene/acrylic acid, alkyd, polyester, and epoxy coatings, and can also be used in nitrocellulose coatings.