This article introduces the operational guidelines for on-site measurement of wet film thickness of coatings using a wet film comb gauge. First, it explains the measurement principle of the wet film comb gauge, which involves estimating thickness by observing the extent to which the teeth are coated with the paint. Next, the article details the preparatory steps before operation, including inspecting the coating condition and selecting an appropriate comb gauge. The standard operating procedures include selecting measurement points, cleaning the comb gauge, pressing it vertically into the coating, reading and recording the values, and cleaning it for repeated measurements. Additionally, the article emphasizes factors that can affect measurement results, such as substrate roughness and operating techniques, and highlights the importance of data recording and processing. Finally, it concludes by stressing the significance of adhering to standardized procedures to ensure measurement accuracy and coating quality.
2026-04-17
This article introduces how laboratory dispersers efficiently disperse paint pigments. They break down pigment agglomerates through mechanical actions such as shear force, involving three stages: wetting, dispersion, and stabilization. The dispersion effect is influenced by multiple parameters, including rotor linear speed, time, and viscosity, requiring the selection of appropriate equipment types based on material characteristics. For instance, high-speed dispersion discs are suitable for low-viscosity systems. Process optimization can be achieved through stepwise speed increases and temperature control, while regular equipment maintenance and operational safety are essential. Current technology is advancing toward intelligence and precision, with integrated sensors and modular designs enhancing the control efficiency and flexibility of the dispersion process.
2026-04-17
In paint production, accurate color evaluation is crucial. Visual color comparison is susceptible to the influence of light, as natural light is unstable, and different types of lighting can make colors appear different. A standard light box provides a stable and controllable lighting environment, simulating common light sources such as daylight, which helps observers more reliably compare color differences. It adheres to relevant technical standards, supports standardized color comparison processes, and assists with instrumental measurements for final verification. This reduces errors in color judgment and enhances the reliability of quality control.
2026-04-17
The Barcol hardness tester is a portable device suitable for rapid on-site hardness testing of coatings. It measures hardness by gauging the depth of penetration of the indenter, offering simple operation and completing tests in just a few seconds. Compared to traditional laboratory methods, it is highly portable, has minimal requirements for workpiece shape, and allows for micro-destructive testing directly on the surface of large components, significantly improving on-site evaluation efficiency. When using the device, attention should be paid to coating thickness and surface flatness, and the instrument should be calibrated regularly to ensure reliable results.
2026-04-17
This article introduces how the Brinell hardness tester is used to measure the hardness of plastics and soft metal coatings. The Brinell hardness test involves pressing a tungsten carbide ball indenter into the material surface under a specific load, measuring the diameter of the indentation to calculate the hardness value, making it suitable for testing these softer materials. The article mentions that during testing, appropriate load and indenter size should be selected based on the coating thickness and material type, and standardized procedures should be followed, such as cleaning the surface and taking multiple measurements for an average. It also notes that this method may not be suitable for ultra-thin coatings, suggesting a combination of other methods for comprehensive performance evaluation.
2026-04-17
The coating test card is an integrated testing tool used to evaluate the appearance and film thickness uniformity of coatings. It involves applying the coating onto a standard card, observing appearance defects such as pinholes and orange peel after curing, and measuring the dry film thickness at multiple points to calculate the coefficient of variation, thereby quantifying the film thickness distribution. This method is fast and intuitive, commonly used for quality control in industries such as printing and furniture coating. However, the results are primarily used for relative comparisons and require calibration with actual workpiece testing.
2026-04-17
Coating rate card paper is a standardized substrate used for determining the coating rate of architectural paints. It features a flat surface and stable parameters, which help reduce the influence of substrate variations and environmental factors associated with traditional methods. During use, the change in mass of the card paper before and after coating is measured. Combined with the paint density and coating area, this allows for the calculation of the dry film thickness and actual coating rate. This method is simple to operate, yields reliable results, and aids in accurately assessing the coverage performance of paints in laboratory settings. It also supports product comparison and optimization.
2026-04-17
This article introduces how to use a friction and wear testing machine to evaluate the wear resistance of self-lubricating polymer materials. It explains the working principle of the testing machine, including the basic formulas for measuring the friction coefficient and wear rate. It emphasizes that test conditions must be set based on practical applications, as factors such as load, speed, and temperature can influence the results. The evaluation primarily focuses on the stability of the friction coefficient, the wear rate, and the condition of the worn surface. The article also mentions that different modification methods have varying effects on wear resistance, requiring analysis in conjunction with specific materials. Finally, adhering to relevant testing standards ensures the comparability of data. Overall, this testing method helps in gaining a deeper understanding of the tribological behavior of materials and guides their development and application.
2026-04-15
A rotational rheometer measures rheological parameters such as viscosity of polymer melts by applying a controlled shear field. Melts typically exhibit shear-thinning behavior, where viscosity varies with shear rate, directly influencing processing methods like extrusion and injection molding. Testing requires attention to factors such as sample preparation and temperature control to ensure reliable data. Rheological results can be used to evaluate processing behavior, optimize processes, and help analyze common issues such as surface roughness and product deformation.
2026-04-15
This article introduces a method for determining residual monomers in polymer solutions using ultraviolet spectrophotometry. The principle relies on the characteristic absorption of monomers in the ultraviolet region, calculating their content based on the relationship between absorbance and concentration. During operation, a standard curve must first be prepared, and then the absorbance of the sample is measured for comparison. The article highlights the importance of considering factors such as background interference, wavelength selection, and instrument cleanliness to ensure accurate results. This method is simple to operate, cost-effective, and suitable for detecting monomers with ultraviolet absorption.
2026-04-15
This article explores how to assess and regulate the stability of polypropylene's flowability in injection molding processes by measuring its melt flow rate. It explains the principles of characterizing flowability and analyzes the impact of factors such as material batch variations and process parameters on stability. By establishing a baseline for the flow rate of raw materials, measurement data can be correlated with adjustments in process parameters such as injection speed and temperature, enabling monitoring and optimization of the production process. Regular measurements and data analysis help reduce product quality fluctuations and enhance the stability and controllability of the injection molding process.
2026-04-15
This article introduces how to optimize the heat-sealing window of polyethylene packaging films using a heat-sealing tester. The heat-sealing window refers to the temperature range within which a film can be effectively sealed. A wider window indicates better process stability. The article explains the concept of the heat-sealing window, describes the testing methods and instruments, and analyzes the influence of material and process parameters, such as film density and heat-sealing pressure. Through testing, the optimal combination of parameters, such as temperature and pressure, can be identified, thereby balancing heat-sealing strength and window width to enhance the reliability of packaging seals. The optimization process should be based on test data and conducted in accordance with industry standards.
2026-04-15
This article explains how to measure the right-angle tear strength of films using an electronic tensile testing machine. During the test, a film specimen with a right-angle notch is clamped into the testing machine and stretched at a constant speed, while the machine records the changes in force during the tearing process. By analyzing the relationship between force and displacement and combining it with the specimen thickness, the tear strength can be calculated. The article details the equipment requirements, specimen preparation methods, specific operational steps, and data processing procedures. It also highlights the importance of factors such as specimen quality, clamping condition, and testing environment to ensure accurate and reliable results.
2026-04-15
This article introduces how to adjust the addition amount of slip agents in film production using a friction coefficient tester. By measuring the dynamic and static friction coefficients of the film, the surface slip performance can be quantified. Based on the test data, the proportion of slip agents can be systematically adjusted to achieve the target friction coefficient range, thereby optimizing the production process. Meanwhile, these data also help monitor production consistency and promptly identify process deviations. During operation, attention should be paid to sample preparation, instrument calibration, and uniformity of test conditions, while also considering the impact of slip agent migration on long-term performance.
2026-04-15
This article introduces how to use a seal tester to evaluate the pressure resistance and leakage performance of composite film bags. The test primarily involves applying controlled pressure inside the packaging and observing pressure changes or leakage to assess the quality of the seal. The instrument includes components such as pressure control, a sample chamber, and sensors. During testing, samples must be placed according to the steps, parameters must be set, and the pressure resistance test involves observing the burst pressure, while the leakage test focuses on the pressure stability or the presence of bubbles during the pressure-holding period. Key aspects include controlling parameters such as the pressure range, accuracy, and pressure-holding time. Proper operation and result analysis can help identify weak points in the seal, providing a basis for improving packaging.
2026-04-15
This article explains how to determine the low-temperature embrittlement temperature of plastics using a high-low temperature alternating test chamber. The low-temperature embrittlement temperature refers to the critical temperature at which plastics transition from toughness to brittleness, which is crucial for evaluating the impact resistance and safety of materials in cold environments. During testing, standard specimens are placed in the test chamber for cooling, then quickly removed for impact testing to observe fracture behavior. By repeating the tests at different temperatures, the embrittlement rate is calculated to identify the embrittlement temperature. The test results are influenced by factors such as temperature uniformity and transfer time. This method is widely used in industries such as automotive, wires, and cables, providing critical data for material selection and product design.
2026-04-15
The thermogravimetric analyzer measures the mass change of polymer materials during heating to determine their moisture and volatile content. During testing, the sample is heated at a controlled rate in a regulated atmosphere. Moisture and volatiles evaporate or decompose at lower temperature ranges (e.g., 50–150°C), leading to a reduction in mass. The content percentage can be calculated from the thermogravimetric curve. Factors such as sample preparation, heating rate, and atmospheric conditions must be carefully considered in this method, which is widely applied in quality control and process optimization for materials like plastics and rubber.
2026-04-15
This article introduces a method for determining the phase transition temperature of liquid crystal polymers using differential scanning calorimetry. Differential scanning calorimetry analyzes the phase transition behavior of materials by comparing the heat difference between the sample and a reference material, recording the heat flow curve during temperature changes. The article details the calibration before testing, key points of sample preparation, and the influence of conditions such as heating rate and sample amount on the results. The data analysis section explains how to identify features such as the glass transition and crystalline-liquid crystal transition from the curve, and demonstrates the practical application process through examples. This method provides important references for the research and processing of liquid crystal polymers.
2026-04-15
This article introduces how to use a constant temperature and humidity aging chamber to test the hygrothermal aging performance of composite materials. Hygrothermal aging refers to the process where the performance of materials gradually declines under the combined effects of temperature and humidity. During testing, accelerated aging is simulated by precisely controlling the temperature and humidity inside the chamber, allowing moisture to penetrate the material, which may lead to performance degradation. The test must follow relevant standards, and the process includes preparing specimens, setting conditions, periodic sampling, and performance comparison. Key evaluation indicators mainly include mechanical properties, physical properties, and changes in microstructure. Analyzing the results helps in understanding the aging patterns of materials and provides a basis for product design and lifespan prediction. This method effectively assesses the durability of composite materials in hygrothermal environments.
2026-04-15
Differential scanning calorimetry (DSC) is a commonly used technique for studying the curing reactions of thermosetting polymers. By measuring the heat released by the sample during the heating process, key parameters such as reaction heat and curing temperature can be obtained. During experiments, it is necessary to calibrate the instrument, control the sample mass and heating rate to ensure accurate results. This method can be used to analyze the curing characteristics of materials such as epoxy resins, assisting in optimizing formulations and processes.
2026-04-15
