What are the common error methods of desiccant test?

Many customers will immediately test the moisture absorption effect of the desiccant when they receive a desiccant sample. But I found that the moisture absorption effect of the desiccant is far from what we promised. Is the moisture absorption effect of the desiccant problematic, or is there a problem with the test method of the desiccant?
Mistake 1:
Many customers It is said that the desiccant is hygroscopic, just throw it in the water, and see if it is full after a few hours.
Desiccant is a desiccant that maintains space by absorbing moisture (moisture) in the air. Usually, the role of desiccant is water vapor rather than liquid water, and the target object is not selected correctly.
   High-quality desiccants will use waterproof and breathable packaging materials, because desiccants absorb water vapor in the air instead of liquid water. If the desiccant is directly thrown into the water, under the action of liquid water, the water should be an impenetrable waterproof and breathable packaging material, otherwise the water can enter but also reverse ooze out (similar to a sponge), thus losing the desiccant itself The moisture absorption and anti-reverse osmosis effect.
   After the desiccant absorbs moisture, the moisture should be absorbed in the desiccant, and there should be no moisture on the surface. If you take out the desiccant soaked in water, it will definitely drip. This also shows that the test method of throwing the desiccant directly into water to soak and absorb moisture is wrong.
Wrong way two:
After the customer took out the sample, he poured a glass of water directly on it to see if the desiccant quickly absorbed moisture?
The desiccant absorbed the moisture in the air to achieve the environment Relatively dry, the main ability is to absorb moisture in the air rather than liquid moisture. It is not a sponge. The super absorbent resin (a commonly used raw material in baby diapers) is used to absorb liquid water, so it is a mistake to pour the water directly on the desiccant to test the moisture absorption effect. (Note: Some desiccant manufacturers use this kind of material as a desiccant, and post a video on the Internet to show how effective this kind of desiccant is when poured into liquid water. In fact, this is a behavior to deceive customers. The water adsorption performance is very good, but it cannot be used to adsorb water vapor in the air.)

Wrong way three:
When testing the moisture absorption effect of the desiccant, some customers opened the desiccant outer bag and only took the desiccant raw materials (granules or powder) For testing, this approach is also wrong.
Confused the concept of desiccant raw materials and finished products. The desiccant raw material refers to the inner packaging of the desiccant, which is the content inside the desiccant. Any one of the desiccant contents can be called the desiccant raw material. Some desiccant products are composed of a single desiccant material, such as silica gel desiccant, mineral desiccant, and some desiccants are formed by mixing two or more chemicals (such as container desiccant, calcium chloride desiccant Wait).
    Ignore the role of the desiccant outer packaging bag in the desiccant product, the desiccant outer packaging bag is an inseparable part of the desiccant. Therefore, when testing, you can't just test the contents of the raw materials. In fact, to a certain extent, packaging materials are more important than raw materials. Especially in the packaging of food and medicine, the packaging material of the desiccant is directly in contact with the product. Moreover, the packaging material strength, air permeability and other properties directly determine the quality of the desiccant.
Mistake 4:
Put the desiccant directly in the indoor environment for testing, but the moisture absorption effect is not good. The temperature and humidity of the desiccant test environment are unstable. The ambient temperature and humidity have a significant impact on the moisture absorption capacity of the desiccant. The open test environment can only be used to make a qualitative comparison of different desiccant products year-on-year. If quantitative analysis is required, it must be tested in a constant temperature and humidity environment, and professional equipment "constant temperature and humidity box" is required, so that the data obtained from the test has reference significance. Then there is no professional "constant temperature and humidity box" equipment, you can also use a simple method to replace it, the method is as follows: (1) Preparation materials: 2 plastic cups, a piece of fiber paper with good air permeability and hardness, A package of unopened desiccant samples.
(2) Use a plastic cup to fill a cup of hot water, put it on a flat table, and put the white paper on the plastic cup (the plastic cup should not touch the water).
(3) Open a packet of desiccant, take out a sample of the packet, weigh it, and record the weight M1 of the desiccant before it absorbs moisture.
(4) Put the desiccant on the fiber paper and quickly cover it with another plastic cup to maintain a sealed environment.
(5) Record the weight M2 of the desiccant at 12h, 24h, 36h, 48h, etc. respectively. (The water droplets on the surface of the desiccant should be wiped as accurate data)
(6) Use (M2-M1)/M1*100% to get the moisture absorption rate of the desiccant at different times.
(7) Continue to observe until the weight of the desiccant no longer increases, and the maximum moisture absorption rate of the desiccant is obtained.
If the desiccant sample is too large, you can use a plastic airtight box (food preservation box is fine), a small bowl, and a weight-bearing wire mesh (plastic bowl, breathable white paper can be used) to simulate drying The airtight environment required for the agent to absorb moisture. Note: If you need to measure the moisture absorption rate in a short period of time, you can replace the hot boiled water after the water in the cup is found to be cooled. The purpose of using hot boiled water is to evaporate quickly enough for the desiccant to absorb moisture in a short time and reach saturation status.
Note: If you need to measure the moisture absorption rate in a short period of time, you can replace the hot boiled water after you find that the water in the cup has cooled. The purpose of using hot boiled water is to evaporate the water quickly enough so that the desiccant can be used in a short time The internal moisture absorption reaches saturation.