Comparison of preparation techniques of 5 kinds of non-woven medical protective materials

Non-woven medical protective materials were developed in the 1990s. At that time, some developed countries in Europe and America used non-woven advanced technology to develop a spunlace nonwoven fabric with low cost, appearance and feel close to traditional textiles, which became an alternative to traditional textiles. Excellent material. Up to now, the processing methods of non-woven medical protective materials have been relatively mature. According to the different preparation techniques, there are mainly spunbond, meltblown, SMS composite technology, spunlace and flash.

Spunbond nonwoven technology

As a protective material, spunbonded nonwovens meet the requirements for strength and comfort, but are relatively weak in barrier properties. In response to this problem, fine denier spunbond technology has become a research hotspot. Germany's Freudenberg company first invented the two-component spunbond spunlace technology, using a hollow orange-spinning spinning assembly to extrude the melt stream from the orifice, after cooling and blowing, air drafting The filaments are formed on the web curtain, and the high-pressure spunlace technology is used for the opening and fixing of the filament. The barrier property is better than that of the ordinary spunbond or spunlace nonwoven material, so it can be used for medical protective materials.

Turkish woven fabric manufacturer Mogul recently introduced a material that can be used in surgical gowns. The fiber after opening is 100 times thinner than the hairline, which blocks microbes, has anti-blood and alcohol properties, and has good properties. Its moisture absorption, heat insulation, microporous structure and protective properties of this non-woven material make it an ideal material for medical protective clothing.

Meltblown nonwoven technology

The biggest characteristic of the melt-blown method is that the fiber is very fine, the structure is fluffy after self-bonding, the porosity is high, the average pore size is small, and the barrier property is very good, but the strength and wear resistance of the product are not high. Some people have made improvements on this basis, taking advantage of the spunbond technology, in the case of ensuring the fiber fineness, the short-distance cooling of the melt stream sprayed by hot air, and then through the thermal bonding fixed network It has been found that the strength of the product has been improved and can be applied to occasions where the strength is not too high.

Considering the problem of fine melt-blown fiber and poor compression back, 3M Company of the United States took the lead in the development of intercalation melt-blown technology, in which the process of conventional melt-blown production is blown into the melt-blown fiber stream into coarse-denier and high-coiled Hollow elastic short fibers, under the same gram weight, the compression resilience of the product is greatly improved, the structure becomes more fluffy, and the gas permeability and moisture permeability are also improved; in addition, the path of the particles passing through the material becomes long and narrow, thereby The interception effect is increased, so that the barrier effect on the particles is greatly improved.

Another way to improve the breathability and moisture permeability of the meltblown nonwoven material while greatly improving the performance of blocking the fine particles is the electret method. The electret melt-blown nonwoven material can capture more particles of opposite charge by electrostatic adsorption mechanism, thereby greatly improving the filtration performance.

SMS composite technology

In view of the poor barrier effect of the spunbonded nonwoven material and the low strength of the melt-blown nonwoven material, some people use the strength and wear resistance of the spunbonded fabric as the surface layer, and use the barrier property of the melt-blown fabric as the core layer. An SMS composite nonwoven material was prepared. In view of the fact that most of the current SMS composite protective materials use PP as a raw material and have poor protection against various radioactive materials, Liu Xing et al. of Tianjin University of Technology cooperated with a certain department of the Navy to coat the SMS materials with barium sulfate. It can prevent the penetration of radioactive materials, so it can be used for medical personnel to avoid unnecessary radioactive substances, causing lesions and better isolation and protection. The coating material can also be coated in the form of a sustained-release microcapsule, and when subjected to an external force, the microcapsule is broken and the protective property is enhanced.

Spunlace nonwoven technology

For the non-woven materials in which the short fibers are combed into a net and then hydroentangled and fixed, although they have great advantages in the performance of soft skin, moisture absorption and breathability, they can only be used as general medical materials because of poor barrier properties. The protection performance is not very good. As early as 2009, the University of Leeds developed a class of functionalized spunlace nonwovens that used special equipment to create a hole structure in the spunlace process during the spunlace process. Sustained release disinfectant capsules can be added.

The functional spunlace nonwoven material with the slow release disinfectant microcapsule can be made into a cross-infective protective material, placed in a door handle, a handrail, etc. where the hospital is in contact with the human body, and when the person pushes the door or closes the door, the disease is sick. The patient will pass the germs through the hand to the contact handle. At this time, the microcapsules will release the disinfectant under the pressure of the human hand, effectively killing the bacteria, and other patients or healthy people will not be infected if they touch the handle again. This type of anti-cross-infective nonwoven protective material has been used in some hospitals in the UK and works very well.

Flash nonwoven technology

Compared with SMS, the flashing technology is formed by the solution spinning method, the solvent is a volatile organic solvent, and the recovery is difficult. The high concentration in the air is likely to cause an explosion accident; in addition, in the production process, the fiber is spun. Speed ​​control is very difficult. At present, the technology is monopolized by DuPont of the United States. Its protective clothing made by the flash method Tyvek combines protection, durability and comfort to protect workers from small to micron particles, but at a relatively low cost. Higher. Xia Lei and others from Tianjin University of Technology are studying the localization technology of the flash process. At present, they have established a pilot production line in cooperation with Shandong Qingdao Huashijie Environmental Protection Co., Ltd.