Test performance, test method and test standard of leveling agent
Leveling agent is a kind of coating additive, which can make the surface of the coating smooth after construction, and reduce the defects such as waves and bubbles on the surface of the coating. Leveling agent is generally a polymer organic compound, its role is to reduce the surface tension of the coating, thereby reducing the accumulation of liquid and bubble formation on the surface of the coating, so that the surface of the coating is smoother. The amount of leveling agent in the paint is small, usually only need to add 0.1% to 1% of the proportion, but for some high-demand coating products, the choice of leveling agent and the amount of addition is very important.
Test performance and standard
The following is the performance of the leveling agent to be tested and the corresponding testing method, as well as the possible testing standards:
Test performance, test method and test standard of leveling agent
| property | Detection method | Detection standard |
|---|---|---|
| appearance | Observe the appearance of the sample | – |
| viscosity | Rotary viscometer, drip method, direct drawing method, etc | – |
| density | Densitometer – | – |
| solubility | Solubility test | – |
| volatility | Oven method | ISO 3251、ASTM D2369、GB/T 1728等 |
| Drying time | Oven method, touch drying method | ASTM D1640、ASTM D869、ISO 9117ect |
| Levelling property | Color difference meter, observation method, patch method | ISO 2813、ASTM D523、JIS K 7105、GB/T 9754ect |
| Adhesive force | Delimiting method, stripping test | ASTM D3359、ASTM D6677、GB/T 9286ect |
| Abrasion resistance | Abrasion testing machine | ISO 7784、ASTM D4060、JIS K 7204、GB/T 1768ect |
| Chemical resistance | Chemical tolerance test | – |
| Heat resistance | Constant temperature oven method, high temperature expansion test | ASTM D2485、ISO 10524、GB/T 19547ect |
| Resistance to moisture and heat | Constant temperature wet heat test | ASTM D2247、GB/T 1740ect |
| Light resistance | Light aging test, ultraviolet aging test, artificial climate aging test, salt spray test | ASTM G154、ASTM G155、GB/T 1865ect |
| Oxidation resistance | High temperature oxidation test | ASTM D7528、GB/T 21774ect |
| Low temperature flexibility | Low temperature bending test | ASTM D522、GB/T 6742ect |
Test performance, test method and test standard of leveling agent
It is necessary to select appropriate detection methods and standards according to different types of leveling agents and application scenarios, and pay attention to the accuracy and repeatability of detection.
Detection method
The following is the performance of the leveling agent to be tested and the corresponding testing method:
Appearance: Observe the appearance of the sample and check whether there are bad phenomena such as color difference, suspended matter and precipitation.
Viscosity: It can be measured by rotating viscometer, drip method, direct drawing method and other methods. The rotary viscometer can measure the viscosity, fluidity and other properties of leveling agent. Drip method can be used to test the flow performance of paint, usually using centrifugal drip meter or tube drip meter; The direct stretching method is suitable for the measurement of high viscosity coatings.
Density: The density of the leveling agent is measured using a densitometer, usually a tube densitometer or an electronic densitometer.
Solubility: Solubility test can be carried out, the leveling agent is mixed with the solvent and observed and judged, and it can also be analyzed by instruments such as GC-MS.
Volatility: can use oven method to determine the volatility of the paint, according to a certain temperature and time conditions, measure the quality of the paint change, calculate the volatile content. Testing standards include ISO 3251, ASTM D2369, GB/T 1728, etc.
Test performance, test method and test standard of leveling agent
Drying time: can be measured by oven method, touch drying method and other methods, according to the degree of coating drying to evaluate the length of drying time. Testing standards include ASTM D1640, ASTM D869, ISO 9117, etc.
Flatness: It can be measured by color difference meter, observation method, patch method and other methods to evaluate the flatness and gloss of the coating surface. Testing standards include ISO 2813, ASTM D523, JIS K 7105, GB/T 9754, etc.
Adhesion: The bonding strength between the coating and the substrate can be measured by means of grid method and peel test. Test standards include ASTM D3359, ASTM D6677, GB/T 9286, etc.
Wear resistance: Wear testing machine can be used to measure the wear resistance of the coating. Testing standards include ISO 7784, ASTM D4060, JIS K 7204, GB/T 1768, etc.
Chemical resistance: Chemical resistance test can be used to soak in chemical reagents to test the resistance of the coating to chemical reagents.
Water resistance: soaking test, spray test and other methods can be used to measure the coating’s resistance to water. Testing standards include ISO 2812-2, ASTM D2247, JIS K 5600-7-1, GB/T 1733, etc.
Weather resistance: artificial climate aging test, natural climate aging test and other methods can be used to measure the durability of the coating under different climatic conditions. Testing standards include ASTM D4587, ISO 11507, JIS K 5600-5-7, GB/T 1865, etc.
Fire resistance: flammability test, combustion test and other methods can be used to measure and evaluate the fire resistance of the coating. Testing standards include ASTM E84, GB/T 8626, etc.
VOC content: It can be measured by gas chromatography to evaluate the content of volatile organic compounds in coatings. Testing standards include ASTM D6886, JIS K 0561, GB/T 23985 and so on.