How to avoid the decrease of electrostatic effect of melt-blown cloth | JINHAOCHENG

The filtration efficiency of Melt spraying cloth is a complex system engineering, which involves the product material, product process, electrostatic electret technology and so on, and has a lot to do with the storage environment. How to avoid the decline of the electrostatic effect of 95 grade Melt spraying cloth, it is necessary to do a good job from the following three aspects.

Wide melt spray cloth production

1. Selection of permanent electret masterbatch

Electret is to recharge. The melt blown cloth passing through the electret reached 95 + at first, but the effect fell after a few days, mainly because the electrostatic field was extremely unstable and the charge attenuation caused the attenuation of the effect.

At present, there are three commonly used electret masterbatches: tourmaline production, gas-silicon production, nitrogen-containing chemicals fatty acids.

Each of the three types of electret masterbatch has its own advantages and disadvantages. The electret masterbatch produced by gas-silicon method has high efficiency and good persistence, which basically belongs to permanent power storage, easy to disperse, non-toxic and tasteless, and can be certified by FDA.

The polarization of electrets made of non-polar materials is mainly caused by space charge. There are two types of space charge: one is called the same sign charge, the other is called the different sign charge. The former is attributed to the existence of conductivity between the dielectric and the electrode or the breakdown near the dielectric surface under the action of a strong electric field, which causes the electrode to inject charge into the dielectrics, so that the polarity of the injected space charge is the same as that of the adjacent electrodes. The polarity of the different sign charge is opposite to that of the adjacent electrode, which is mainly due to the separation and capture of the charge in the dielectric. The electret charge formed by dipole orientation in polar dielectrics is another type of different sign charge.

2. Electret equipment should use positive charge

The dust, bacteria and viruses in the air are attached to the particles, which are mainly negatively charged, while the melt blown cloth is positively charged, so it is easy to absorb these negatively charged particles.

Electret equipment should use positive charge, not negative charge. Because there is a positive charge on the cloth, it can absorb the negative charge in the air. When the melt-blown cloth comes into contact with the skin, the negative charge is more easily consumed, and the loss is slower if the positive charge is carried.

According to the engineer of an electrostatic equipment, the test shows that the best discharge distance between 15-50KV is 4-8cm.

If the applied voltage is too high, such as more than 50KV, it is easy to destroy the molecular structure of polypropylene. If you get too close, an arc spark will break through the meltblown cloth. Depending on too far, the charge escapes because of scattering, which wastes a lot of charge and cannot be embedded in the masterbatch, resulting in insufficient electrostatic field of the cloth.

High-power electret equipment for electrostatic blown cloth.

The electret energy can be adjusted in a wide range and the power regulation range is 0-1200W.

Output electret voltage adjustable range 0-60KV.

Output electret current 0-20mA.

Real-time liquid crystal display electret voltage and current.

With start button and adjustment button for easy operation.

With emergency stop switch, emergency failure terminates the output with one button to improve safety.

With automatic rapid arc detection and fast arc extinguishing function to ensure the safe and uninterrupted operation of melt blown cloth.

With discharge molybdenum wire broken wire fast protection function to ensure safety and electret effectiveness.

With output electret overvoltage, overcurrent, overpower protection.

Real practical electrostatic electret generating equipment.

3. Meltblown cloth should be encapsulated in time to avoid moisture regain

The static electricity of meltblown cloth has a very strong adsorption capacity, and the dust and water vapor in the air will be constantly absorbed by meltblown cloth. Environmental problems greatly affect the charge retention of meltblown cloth.

Therefore, it is necessary to monitor the temperature and humidity in the workshop at all times and increase the corresponding equipment to keep the temperature and humidity in the workshop within a certain range.

Meltblown cloth should be packaged in time after production, preferably vacuum packaging, dry storage, can not come into contact with the outside wet air. Avoid regaining the moisture and getting dirty.