The vacuum decay leak tester is a non-destructive testing device that quantitatively detects leaks by monitoring minute pressure changes in the test chamber after vacuum evacuation. It is suitable for checking the seal integrity of various packaging types, such as food, electronics, daily chemicals, and medical devices. This method offers advantages such as high sensitivity, rapid testing, and no damage to samples. However, it may have limitations for soft packaging or packages fully filled with liquid. Calibration is required before use, and method validation should be performed in accordance with relevant standards.
2026-04-03
The sand falling tester evaluates the abrasion resistance of powder coatings by simulating sand particle impact. During the test, abrasive particles fall vertically from a specified height, continuously eroding the coating until the substrate is exposed. The wear resistance is assessed based on the mass of abrasive consumed. This method is widely used for coating evaluation in sectors such as construction, household appliances, and automotive industries. Test results are influenced by factors including abrasive properties, flow rate, and coating thickness, and standardized operation is required to ensure accuracy. The data can be used to compare the performance of different coatings or monitor product quality.
2026-04-03
This article introduces the method for testing the impact resistance of powder coatings using an impact tester. The test simulates instantaneous impact through a falling weight or pendulum, conducted in accordance with ISO or ASTM standards. Steps include sample preparation, setting the impact energy, and inspecting the coating for cracks or peeling after impact. Results are evaluated based on energy values or pass/fail criteria, with influencing factors including coating thickness and curing degree. This test is used in industries such as automotive and home appliances to optimize coating quality and enhance product durability.
2026-04-03
This article introduces the method of testing the damping hardness of powder coatings using a pendulum hardness tester. The test is based on the principle of energy attenuation, where the hardness is reflected by the time it takes for the amplitude of the pendulum to decay as it swings on the coating surface—the longer the time, the harder the coating. The commonly used types include the König pendulum and the Persoz pendulum. The test must be conducted according to standard procedures, paying attention to factors such as coating curing, environmental conditions, and substrate thickness to ensure accurate results. This method is primarily used for quality control and research and development comparisons, helping to evaluate the mechanical properties of coatings.
2026-04-03
This article introduces the method of determining the moisture content in powder coatings using the Karl Fischer moisture analyzer. Excessive moisture content in powder coatings can affect coating quality, leading to issues such as bubbles. The Karl Fischer method measures moisture through the quantitative reaction of iodine and sulfur dioxide, divided into volumetric and coulometric methods, which are suitable for different moisture content ranges. During measurement, attention should be paid to sample handling, instrument calibration, and solvent selection, along with quality control to ensure accurate results. This method effectively supports the production and process control of powder coatings.
2026-04-03
This article introduces the method of testing the tensile strength of hot melt adhesive using a universal material testing machine. During the test, dumbbell-shaped specimens must first be prepared according to standards and conditioned in a constant temperature and humidity environment. The testing machine should be correctly set in terms of speed and parameters, and after clamping the specimen, it is stretched until fracture, with load and displacement data recorded. Tensile strength, elongation at break, and other results can be obtained through calculation to evaluate the mechanical properties of the hot melt adhesive. The test should pay attention to factors such as specimen quality and test speed, and follow standards such as ISO and ASTM to ensure reliable results.
2026-04-03
This article introduces the standard method for measuring the peel strength of hot melt adhesives using an electronic tensile testing machine. The test adopts the 180° peel mode, where a sample coated with hot melt adhesive is clamped in the grips of the tensile testing machine and peeled at a constant speed. The peel strength is calculated based on the recorded force variations. The method details the required equipment, sample preparation steps, testing procedures, and data processing methods, and emphasizes key influencing factors such as substrate surface and adhesive application techniques. This method is applicable across multiple industrial fields and is primarily used to evaluate the static bonding performance of hot melt adhesives.
2026-04-03
This article introduces how the T-peel strength tester is used to evaluate the performance of hot melt adhesives. The tester simulates scenarios where materials are subjected to peel stress, measures and records the force and displacement during the peeling process, thereby calculating the average peel strength and assessing the uniformity of adhesion. In the research, development, and quality control of hot melt adhesives, peel strength is a key indicator. Testing helps analyze failure modes and guides formulation optimization. The testing must follow standard procedures, including sample preparation, environmental control, and data recording. By interpreting the force-displacement curve, the adhesive state can be determined, providing direction for improving adhesive formulations. This test is widely applied in industries such as packaging, textiles, and furniture, offering data support for product selection and process optimization.
2026-04-03
This article introduces how to use a tack retention tester to evaluate the cohesive strength of hot-melt adhesives. During the test, a sample coated with hot-melt adhesive is attached to a test plate, and a weight is suspended to apply continuous shear stress. The time until detachment or displacement is recorded, which directly reflects the internal cohesion of the adhesive. The test must comply with national or international standards, with strict control over parameters such as temperature and weight mass. The chemical composition and structure of the hot-melt adhesive influence the test results, which are reflected in the duration of tack retention. This method is primarily used to assess performance under static loads and provides guidance for product development and quality control. However, it should be noted that it does not fully reflect performance under dynamic or complex environmental conditions.
2026-04-03
The initial tack tester is a device used to measure the initial adhesive performance of pressure-sensitive hot melt adhesives, primarily through the rolling ball method or probe method to assess the adhesive force at the moment of contact. Testing must comply with national standards, such as GB/T 4852, to ensure accurate results. This type of testing is crucial for adjusting adhesive formulations, optimizing processes, and ensuring quality control, and it is widely applied in industries like packaging and labeling. Regular maintenance and calibration of the instrument are essential to guarantee the reliability of the tests.
2026-04-03
This article introduces the method of testing the environmental adaptability of hot melt adhesive using a constant temperature and humidity chamber. The performance of hot melt adhesive is easily affected by temperature and humidity, and the purpose of the test is to evaluate its stability under different climatic conditions. The article explains the testing principles, equipment requirements, sample preparation steps, and how to design temperature and humidity conditions, such as high temperature and high humidity or low temperature and dry conditions. The key is to assess the durability of the adhesive by measuring changes in strength, thermal properties, and appearance. The test helps understand the product's performance in actual use and provides a basis for quality control and product application.
2026-04-03
This article introduces the method of evaluating the thermal aging life of hot melt adhesives using a high-temperature oven. The principle is based on the Arrhenius equation, where aging is accelerated by increasing the temperature to simulate performance changes under long-term use. During the experiment, hot melt adhesive samples are placed in ovens at different high temperatures, and key properties such as bond strength are tested periodically. Data is recorded until the performance degrades to the failure criteria. The data is then analyzed, and the Arrhenius equation is used for extrapolation to predict the lifespan under normal operating temperatures. This method is efficient, but it is important to ensure that the aging mechanisms at high temperatures align with actual conditions. Additionally, it only considers the effects of heat and oxygen, while other factors require additional testing.
2026-04-03
The hot melt adhesive laboratory small-scale coater is a device used for controlled coating of hot melt adhesive onto substrates to support adhesive research, development, and process optimization. Before operation, it is necessary to clean the equipment and preheat it, and set parameters such as temperature, speed, and gap according to the material. During coating, the uniformity of the adhesive layer should be observed, and the equipment should be cleaned promptly after completion. Parameters such as temperature and speed affect the coating results, and optimization should be achieved through single-variable adjustment. When using the equipment, pay attention to high-temperature protection and perform regular maintenance to ensure proper operation.
2026-04-03
This article introduces the method for detecting the moisture content in hot-melt adhesives using a Karl Fischer moisture analyzer. The Karl Fischer method is based on the quantitative reaction of iodine and sulfur dioxide with water, calculating the moisture content by measuring the amount of iodine consumed. For solid hot-melt adhesives, heating is required to melt them, releasing moisture which is then swept into the titration cell by an inert gas for detection. During the measurement, parameters such as heating temperature and carrier gas flow rate need to be optimized to ensure accurate results. The moisture content is calculated using a formula, and the results help evaluate the quality of hot-melt adhesives, preventing performance issues caused by excessive moisture. During operation, it is essential to keep the system dry and regularly verify the reliability of the method.
2026-04-03
This article introduces the operation process of a hot melt adhesive ash content determination instrument. The instrument decomposes organic components by high-temperature incineration of the sample, leaving behind inorganic residues as ash, and calculates the content based on the mass change before and after incineration. Before operation, it is necessary to inspect the instrument, prepare crucibles and other utensils, and ensure proper ventilation. The sample should be uniformly processed into small pieces. The measurement steps include: first incinerating the empty crucible to constant weight and weighing it, adding the sample and weighing it, then carbonizing at low temperature, followed by high-temperature incineration until complete ashing, cooling and weighing the ash mass, and finally substituting the values into the formula for calculation. During the process, safety precautions must be observed, temperature rise must be controlled, and cooling should be carried out in a desiccator. Regular calibration of the instrument and maintaining cleanliness are essential to ensure accurate results.
2026-04-03
This article introduces the method for measuring the shear viscosity curve of hot melt adhesives using a capillary rheometer. The principle involves pushing molten hot melt adhesive through a capillary, measuring the pressure and flow rate, and then calculating the shear stress and viscosity. During testing, it is necessary to set the temperature, load the sample, and measure at different speeds. After obtaining the data, calculations and corrections using formulas are required to plot the viscosity curve. The curve reflects the flow characteristics of the hot melt adhesive under different shear rates, such as whether it thins or thickens. Factors such as temperature control, sample preparation, and instrument calibration can affect the accuracy of the results. These data are helpful for optimizing processing techniques such as coating and spraying of hot melt adhesives.
2026-04-03
This article introduces the standard procedure for measuring the flow rate of hot melt adhesive using a melt flow indexer. The measurement is based on the principle of capillary rheometry, where the flow rate is determined by calculating the mass of material extruded per unit time under specific temperature and load conditions. Before operation, it is essential to prepare the instrument, dry the sample, and gather auxiliary tools while ensuring proper environmental control. Specific steps include preheating the instrument, cleaning and loading the material, applying load after preheating, cutting and sampling, weighing and calculating, and cleaning up afterward. Attention must be paid to factors such as temperature control, sample condition, and loading techniques to ensure accurate results. Finally, data should be recorded systematically, and safety precautions for high-temperature operations must be observed.
2026-04-03
The crystallinity of hot melt adhesive directly affects its properties such as bonding strength. Differential scanning calorimetry captures the thermal effect peaks corresponding to melting and crystallization by measuring the heat flow changes of the sample during heating and cooling processes. The crystallinity can be calculated using the ratio of the melting enthalpy to the theoretical enthalpy of complete crystallization. DSC instruments can systematically analyze the effects of thermal history, processing conditions, and different formulation components on crystallization behavior, providing critical data support for the research and development and quality control of hot melt adhesives.
2026-04-03
This article introduces the method of determining the melting point and glass transition temperature of hot-melt adhesives using differential scanning calorimetry (DSC). Differential scanning calorimetry analyzes the thermal transition characteristics of materials by measuring the energy difference between the sample and a reference. For hot-melt adhesives, the melting point and glass transition temperature are key parameters affecting their processing and performance. During the experiment, the sample needs to be prepared as thin slices or granules, tested under a nitrogen atmosphere at a constant heating rate, and the transition temperatures are determined by analyzing the heat flow curve. The test results are influenced by factors such as sample preparation and heating rate, so standardized procedures are necessary to ensure data accuracy. This method provides reliable thermal performance data support for the research, development, and application of hot-melt adhesives.
2026-04-03
This article introduces the standard method for measuring the melt viscosity of hot-melt adhesives using a rotational viscometer. During measurement, the hot-melt adhesive sample must be fully melted and deaerated, then loaded into the measuring cup, and measured with a rotational viscometer at a set temperature. Key steps include selecting the appropriate rotor and rotational speed, maintaining temperature stability, recording data, and calculating viscosity according to the formula. Attention must be paid to sample uniformity, instrument cleanliness, and regular calibration during operation to ensure accurate and reliable results.
2026-04-03
