Price of PP Melt Blown Special Polar Masterbatch for PP Melt Blown
Source：德创化工Time：2020-04-03Hits：2122
Meltblown cloth for masks must be treated by permanent poles.
For meltblown cloth used for masks, the most important indexes are filtration performance, filtration resistance, charge attenuation, etc. The key is the electret masterbatch and electret treatment process.
This layer is the core part of the electret meltblown cloth with electret master batch and electret high piezoelectric treatment. Only a lot of electric charges on the electret treated meltblown cloth can effectively adsorb the 0.3 micron non-oily small particles with the same electric charges, usually requiring more than 95%, which can only be tested by professional instruments. Some manufacturers also use two layers of 25-28g electret treated meltblown cloth to achieve the effect of 50-60g electret meltblown cloth!
Meltblown cloth for masks must be treated by electrifying (fig. 1)
N95 Respirator
Meltblown cloth for masks must be treated by electrifying (fig. 2)
Meltblown cloth process
Stationary process
Basic composition of electret masterbatch
Polypropylene is used as a base material, and a special auxiliary agent is used, so that the auxiliary agent is uniformly dispersed in the master batch; and 2 to 5 percent is added in the spinning process of the melt-blown cloth, so that the density and depth of charge trapping energy traps in the melt-blown non-woven cloth can be effectively increased, and the comprehensive filtering effect and thermal attenuation resistance of the melt-blown non-woven cloth can be improved. Under the condition of the same fiber fineness and gram weight, the non-woven fabric product resistance is reduced, and the filtering effect of the non-woven fabric product is improved.
Meltblown cloth for masks must be treated by electrifying (fig. 3)
Basic parameters of electret masterbatch:
1. Appearance: cylindrical uniform particles.
2. Bulk density: 0.50 ~ 0.80 g/cm3.
3. Color: white or light yellow
4. Addition: 2.0-5.0%
Role of electret treatment
Meltblown cloth for masks must be treated by electrifying (fig. 4)
We can understand the role of electret masterbatch in meltblown cloth from some data. As can be seen from the following figure, meltblown cloth without electret discharge treatment has very low filtration efficiency. After electret treatment, the filtration efficiency will be greatly improved, but it is often difficult to meet the national standard requirements of N95. After electret masterbatch is added, the filtration efficiency will be further improved. The excellent electret masterbatch formula can make the product reach the level of N95.
Meltblown cloth for masks must be treated by electrifying (fig. 5)
Note: White column has not been treated with electrization, while black column is the result of electrization.
The development of resident masterbatch took more than one day.
Resident masterbatch is a minor product. Before the outbreak of the epidemic, few enterprises produced it. Usually, it was produced by masterbatch and modified material enterprises matching meltblown cloth, and the scale was usually small.
Experience has been accumulated in long-term production. A large number of exploratory tests have been carried out on the formula from additives, selection of basic resin, granulation temperature, screw combination, melt finger control, additive content, etc. Combined with electret treatment, the filtration performance, filtration resistance and other indexes have been optimized. The melt blown cloth made has also been placed for six months, one year, two years or even longer before the filtration performance and other indexes are tested.
Therefore, it is not a modified enterprise or color masterbatch enterprise that can produce qualified resident masterbatch products immediately by starting production and working out the formulation of additives.
In a hurry, some enterprises immediately developed high-efficiency resident masterbatch, which was produced and processed on the melt-blown line, and immediately tested the filtration efficiency to reach 95%, and the filtration resistance was also qualified. However, it is difficult to guarantee the qualification without making it into a medical mask through strict testing.
For some key additives, it is suggested that melt-blown cloth factories should choose the old-line enterprise products that produce resident masterbatch for a long time, which seems to be more reliable.
After all, medical masks are to be held accountable. During the epidemic period, supplies are tight and everything is simple. However, we should not only pursue efficiency, but also be vigilant and do not let small losses outweigh big gains.
Risks Caused by Unqualified Resident Masterbatch
Under the current situation of shortage of meltblown cloth, many enterprises, because they do not know the electrifying technology, do not add electrifying masterbatch to their products, do not carry out electrifying treatment, and sell products with unqualified filtration efficiency, can still meet the demand and sell at high prices. However, in the later stage, they may have to pay the price of violating the law in product tracking and accountability.
Similarly, upstream enterprises saw the business opportunity of resident masterbatch, and developed resident products between warehouses. When they were in the market, they did not undergo long-term product inspection, and the filtration efficiency and long-term effectiveness were not fully verified, which also posed risks.
As can be seen from the following figure, the surface charge of meltblown cloth will decay with time. After the electret masterbatch is added, the decay time will be greatly prolonged. With the appropriate increase of the amount of electret masterbatch, the charge retention rate will also be longer, and the decay rate will be different for different electret masterbatch formulations.
Meltblown cloth for masks must be treated by electrifying (fig. 6)
Some melt-blown cloth merchants, in order to save costs, add less resident masterbatch. Although the mask is qualified in a short period of time and is valid for one month or half a year, the shelf life of medical masks is often 2 years, thus there is a greater risk.
In the environment of huge commercial profits brought about by the epidemic, merchants can make reasonable profits by complying with the market demand, but they still need to reasonably evaluate their own product characteristics, reasonably locate the market area, ensure the product quality, and do not easily risk products that violate the strict requirements of laws and regulations such as medical devices.
Meltblown cloth for masks must be treated by electrifying (fig. 7)
It is suggested that businesses should reasonably evaluate their own products and give full play to their own advantages. When selling meltblown cloth, meltblown cloth manufacturers should not blindly make profits if they cannot meet the standards for medical meltblown cloth.
