In the coatings industry, quality control is one of the key factors to ensure product performance and stability. One of the important quality parameters is the non-volatile content, which reflects the proportion of non-volatile components in the paint. In this paper, the concept of nonvolatile content, its determination method and its importance in coating production will be discussed in depth.

The concept of non-volatile content
Non-volatile refers to the material remaining after volatilization of the paint under specific test conditions. There are usually two ways to determine the non-volatile content:

Gravimetric method: This method involves heating and baking the paint at a certain temperature to evaporate the volatile material, then measuring the mass of the remaining material and comparing it with the total mass of the sample. The non-volatile content is the ratio of residual material mass to sample mass.

Volumetric method: This method requires a certain volume of liquid paint to be coated into a film and cured under specified conditions. Subsequently, the volume of the resulting cured film is measured. The non-volatile content is determined by calculating the volume of the coating film-forming substance.

It is important to note that the non-volatile content is not an absolute value, but depends on the test conditions used, such as heating temperature and time. Due to solvent residues, thermal decomposition and low molecular weight components in volatile components, the measurement results of non-volatile matter content are relative rather than absolutely accurate.

Concept and determination method of non-volatile content

The importance of non-volatile content
In the production of coatings, non-volatile content is a crucial quality control parameter. Its content directly affects the quality of the formed film and the use value of the paint. The following are some aspects of the importance of non-volatile content:

1. Coating quality

The non-volatile content affects the quality and properties of the film. If the non-volatile content is too high, it may cause the film to become hard, fragile, and even crack and crack. Conversely, if the non-volatile content is too low, the coating may lack enough curing material, resulting in insufficient adhesion and reduced durability of the coating.

2. Coating viscosity control

Viscosity is another key parameter in the production of coatings. There is a close relationship between non-volatile content and viscosity. When the viscosity needs to be maintained within a certain range, the content of film-forming substances in the coating can be determined by the determination of non-volatile fractions. This helps manufacturers adjust formulations to ensure stability in viscosity and paint performance.

3. The use value of paint

The use value of the paint depends on its non-volatile content. If the non-volatile content does not meet the specified requirements, the coating may not meet the requirements of the specific application. For example, in automotive painting, accurate control of non-volatile content is essential to ensure that the coating has the appropriate curing speed and coating quality.

Concept and determination method of non-volatile content

Method for determination of non-volatile content
The non-volatile content is usually determined by gravimetric method and volumetric method. These methods have their advantages and applicability in different situations.

1. Gravimetry

Gravimetry is one of the commonly used methods for determination of non-volatile content. It is relatively simple and involves heating the paint at a certain temperature, evaporating the volatile material, and then weighing the mass of the remaining material. This method is suitable for most paint types, especially for those that do not easily form a curing film.

2. Volume method

The volumetric method is usually used for coating liquid coatings as a film, which requires measurement of the volume of the film after curing. This method is suitable for situations where the content of coating film-forming substances needs to be accurately controlled, such as in some special coating processes.

Concept and determination method of non-volatile content

conclusion
Non-volatile content is a key quality control parameter in coating industry, which directly affects the quality of coating film and the use value of coating. With different determination methods such as gravimetric and volumetric methods, coating manufacturers can ensure product consistency and performance stability. In different application areas, accurate determination of non-volatile content is a key step to ensure that coatings meet specific requirements. Therefore, the control of non-volatile content in coating production should be regarded as an indispensable task to ensure product quality and customer satisfaction.