The effect of white tourmaline powde electret masterbatch on meltblown nonwoven

Tourmaline powde electret masterbatch is a kind of material which is made of nano tourmaline powder or particles made of it's and carrier in the process of melt blown non-woven fabric electret. It is charged under 5-10kv high voltage by electrostatic generator to become electret and improve the efficiency of fiber filtration. Because tourmaline has the function of releasing negative ions, it also has antibacterial property.

Tourmaline powde electret masterbatch is a kind of electrolyte material with long-term charge storage function. The electret methods include electrospinning, corona charging, friction electrification, thermal polarization and low energy electron beam bombardment. The tourmaline electret material uses corona charging method to make the fiber carry a certain amount of charge and give the electrostatic filtering function.

Dispersion of nano tourmaline in polypropylene resin

In order to make tourmaline particles dispersed in polypropylene resin, improve the interfacial compatibility between powder and organic matrix, and then improve the mechanical properties of blend fiber, we use titanate coupling agent to modify the surface of tourmaline. In addition, the cross-section of the modified masterbatch shows that tourmaline has been basically evenly dispersed in polypropylene, but there are still a few small agglomerates.

Effect of nano Tourmaline on surface charge density of melt blown nonwovens

After adding nano tourmaline particles, the surface charge density of nonwovens has been greatly improved, especially when containing 6% nano tourmaline particles, the initial surface charge density of melt blown nonwovens is the largest. In addition to the dipole charge of special tourmaline, the reason may be that the polar tourmaline is easy to absorb the free charge produced by corona discharge and make the polarization of polypropylene macromolecule easier. There are two ways of electret charge attenuation: one is that the ions in the air are absorbed into the electret by the electret charge and neutralized with the charge of the electret; the other is that the carriers conducting current in the electret and neutralized with the charge of the electret. This shows that adding too many special tourmaline particles may be detrimental to the charge storage of electret melt blown nonwovens.

Tourmaline powde electret masterbatch on filtration performance of melt blown nonwovens

The filtration efficiency of the sample is greatly improved after the material is treated by corona discharge electret. This is because the electrostatic effect of these electret materials caused by electrets greatly improves the electrostatic adsorption capacity of the materials. When particles pass through the vicinity of electret fibers, they will be strongly adsorbed. With the addition of special tourmaline particles, the filtration performance of electret melt blown nonwovens is further improved, and the filtration resistance is also decreased; with the increase of the mass fraction of special tourmaline, the filtration efficiency of nonwovens increases first and then decreases (6% is better). This may be due to the high mass fraction of nano tourmaline and the uneven dispersion in the fiber, which have a great influence on the structure of the network and the charge storage.

Increasing the charge on the surface of the melt blown cloth can be obtained by the corona discharge electret treatment process, but in order to keep the electrostatic storage constant, the composition and structure of the melt blown electret material are necessary to maintain the charge. The way to improve the charge storage capacity of electret materials can be achieved by introducing additives with charge storage properties.

Therefore, compared with the common melt blown production line, the melt blown production line for air filter materials needs to add high-voltage electrostatic discharge device in the production line, and needs to add electret masterbatch, such as nano tourmaline particles, to the raw material polypropylene (PP).

The above content comes from MUCI mineral company,if you need the white tourmaline powde electret masterbatch,Contract: info@mcreagents.com.