Test method for film-forming and chemical resistance of propylene oxide in coatings?

Test method for film formation and chemical resistance of propylene oxide in coatings

as an important industrial raw material, propylene oxide is widely used in the coating industry. Propylene oxide is mainly used as a film-forming substance in coatings to form a coating film to protect the substrate from the external environment. Because propylene oxide has excellent film-forming properties and chemical resistance, it has been widely used in anti-corrosion coatings, floor coatings and special coatings. This article will analyze in detail the film-forming properties and chemical resistance test methods of propylene oxide in coatings to help readers better understand and apply propylene oxide coatings.

PROPYLENE OXIDE FILM-FORMING CHARACTERISTICS

Propylene oxide is an organic compound containing epoxy groups, and its film-forming properties mainly depend on the crosslinking reaction in its molecular structure. In the coating, propylene oxide by crosslinking reaction with a curing agent (such as amines or acid anhydride compounds) to form a three-dimensional network structure of the coating film. This network structure not only improves the mechanical strength of the coating film, but also imparts excellent chemical resistance and weather resistance.

In the film-forming process of propylene oxide coatings, film-forming additives play a key role. The film-forming aid can reduce the surface tension of propylene oxide in the solvent and promote its spreading and leveling on the surface of the substrate. The film-forming additive can also help propylene oxide to form a uniform and dense coating film during the film-forming process, thereby improving the protective performance of the coating film.

Film-forming test method

In order to evaluate the film-forming properties of propylene oxide coatings, the following tests are usually required:

1. Film Thickness Measurement: The thickness of the coating film was measured using a film thickness meter. The film thickness is an important factor affecting the performance of the coating film. Generally, the more uniform the film thickness, the better the protective performance of the coating film.

2. Adhesion test: The adhesion between the coating film and the substrate is tested by cross-cut method or drawing method. Adhesion is an important indicator to measure the quality of the coating film. The coating film with poor adhesion is easy to peel off and cannot effectively protect the substrate.

3. Tensile strength test: The tensile strength of the coating film was tested by a tensile test. The coating film with high tensile strength is not easy to deform or break under force, and has better mechanical properties.

Propylene oxide chemical resistance

The chemical resistance of propylene oxide coatings is mainly related to the chemical structure of the coating film. Because propylene oxide forms a three-dimensional cross-linked structure during the curing process, the coating film has high chemical stability in the external environment. This cross-linked structure can effectively resist the erosion of chemical substances such as acid, alkali, salt, etc., thereby improving the chemical corrosion resistance of the coating film.

The chemical resistance of propylene oxide coatings is also related to the functional additives used. For example, the addition of anti-aging agents and ultraviolet absorbers can improve the weather resistance of the coating film; and the addition of wear-resistant fillers can improve the wear resistance and impact resistance of the coating film.

Chemical resistance test method

In order to evaluate the chemical resistance of propylene oxide coatings, the following tests are usually required:

1. Soak test: soak the coating film in acid, alkali, salt and other chemical reagents to observe the changes on the surface of the coating film. The chemical resistance of the coating film can be evaluated by observing the occurrence of discoloration, blistering, cracking and the like of the coating film.

2. Neutral salt spray test: The corrosion resistance of the coating film in salt spray was tested by simulating the salt spray environment. The neutral salt spray test is a common method to evaluate the corrosion resistance of coatings.

3. Acid-base alternating corrosion test: The coating film was alternately exposed to acidic and alkaline environments to test the corrosion resistance of the coating film. This method can more realistically simulate the actual use of chemical corrosion in the environment.

Factors Affecting Propylene Oxide Coating Performance

1. Proportion of propylene oxide and curing agent: The proportion of propylene oxide and curing agent directly affects the degree of crosslinking of the coating film. Too low curing agent ratio will lead to insufficient crosslinking, thereby reducing the performance of the film; too high curing agent ratio may make the film too brittle, affecting its mechanical properties.

2. Construction conditions: Construction conditions have an important impact on the performance of propylene oxide coatings. For example, the temperature and humidity during construction will affect the curing speed and crosslinking degree of the film; the pretreatment of the substrate during construction will also affect the adhesion and protection of the film.

3. Coating compatibility: The performance of propylene oxide coatings is also related to the additives and fillers used. For example, the use of anti-aging agents can improve the weather resistance of the coating film; the use of wear-resistant fillers can improve the wear resistance and impact resistance of the coating film.

Conclusion

Propylene oxide has excellent film-forming properties and chemical resistance in coatings, and can provide effective protection for substrates. Through reasonable formulation design and construction technology, the performance of propylene oxide coatings can be further improved to meet the needs of different applications. In the future, with the continuous development of coating technology, the application range of epoxy propane coating will be more extensive, and its performance will be further improved.