Analysis of the characteristics of melt blown cloth

Melt-blown nonwovens are mainly used as composite materials, filter materials, insulation materials, sanitary products, oil-absorbing materials and clean cloths (wipes), battery separators, etc., and are widely used in medical and health, automotive industry, filter materials, environmental protection And other fields. It can be seen from Figure 1-32 that in foreign countries, melt-blown non-woven fabrics are mainly used as two-step SMS materials and medical and sanitary materials and coating materials. In addition, wiping and absorbing materials, filtering and barrier materials are also melt-blown fabrics. Important use. The specifications of meltblown nonwovens for various typical uses are shown in Table 1-8, and the application fields and shares of domestic meltblown nonwovens are shown in Table 1-9. (1) Medical protection. Because the composite material of meltblown cloth and spunbond cloth has high hydrostatic pressure resistance, good air permeability and filtering effect, especially the material compounded with membrane, it has good barrier performance, The filtration efficiency of oily particles can reach more than 99%. For example, medical protective clothing made of composite materials with a quantitative specification of 60-100g/㎡d can effectively block microorganisms, particles and fluids, and is very good for SARS viruses (45nm in size) and HIV viruses (90nm in size). The protective effect. (2) The meltblown composite material with the material for air filtration treated by electrostatic electret has low initial resistance, large dust holding capacity, and high filtration efficiency when used for air filtration. [Under the state of 32L/min flow rate, it is suitable for 0.3um particles The filter efficiency can reach 99.9%, and the resistance is only 117.7Pa (12mm water column)]. It is widely used in the air purification treatment of electronic manufacturing, food, materials, chemical industry, airports, hotels and other places. Melt-blown non-woven fabrics are mainly used as composite materials, filter materials, thermal insulation materials, sanitary products, oil-absorbing materials and clean cloths (wiping cloths), battery separators, etc., and are widely used in medical and health, automotive industry, filter materials, and environmental protection. And other fields. (3) Material for liquid filtration Meltblown non-woven fabric can also be used as liquid filtration material, which can filter particles with a particle size of 0.22~10um. Such as bacteria, blood and macromolecular substances. It is mainly used in the filtration of photosensitive resists in the electronics industry, the filtration of pharmaceutical, biological, and synthetic plasma products in the pharmaceutical industry, the filtration of beverages, beer and Tangjiang in the food industry, the fine filtration of electroplating solutions, the filtration of water purification in water plants, and the purification and filtration of tap water. Click the water hydrogen production device, environmental waste water filtration, etc. (4) Melt-blown non-woven fabrics of thermal insulation materials have the characteristics of large specific surface area, small voids and high porosity. For example, the meltblown nonwoven fiber with an average diameter of 3um [equivalent to an average fiber linear density of 0.0638dtex (fineness of 0.058 denier)] has a necessary variable area of u200bu200b14617cm2/g, and an average diameter of 15.3um [equivalent to average fiber The specific surface area of u200bu200bthe spunbonded nonwoven fiber with a linear density of 1.65dtex (1.5 denier) is only 2883cm2/g. Since the thermal conductivity of air is much smaller than that of ordinary fibers, the air in the pores of the melt-blown non-woven fabric makes the thermal conductivity smaller, and the heat loss through the fiber material of the melt-blown non-woven fabric is very small, and The static air on the surface area of u200bu200bcountless superfine fibers prevents the heat exchange due to the flow of air, so that it has a good heat insulation and heat preservation effect. Polypropylene (PP) fiber is the smallest thermal conductivity of existing fiber materials. It is a melt-blown thermal flake made of PP fiber after special treatment [such as adding 35% of high-tech (coarse) PET three-dimensional crimped fiber] , The thermal insulation performance is 1.5 times that of down and 15 times that of ordinary thermal cotton. Especially suitable for making ski suits, mountaineering suits, bedding, sleeping bags, thermal underwear, gloves and shoes, etc. Products with a basis weight of 65~200g/m2 have been used to make warm clothing for soldiers in cold regions. (5) Oil-absorbing material. Because PP fiber has good hydrophobicity and lipophilicity, it has low density (0.91g/cm3), low water absorption (0.01%), and moisture regain of 0.05%. It is insoluble in oil and stable in acid and alkali resistance. Its chemical properties make it an excellent oil-absorbing material. The oil absorption of the meltblown nonwoven fabric produced from PP raw materials is 15-17 times its own weight, and the water absorption is 0.71~1 times its own weight. It has the characteristics of fast oil absorption, long-term floating on the water surface after oil absorption, and reusability. It is currently the most commonly used oil-absorbing material. (6) Wipe and industrial materials Meltblown cloth is also an excellent wiping material, which can be used for cleaning and wiping precision instruments and equipment, and can also be used as a household wiping cloth. In order to prevent the fiber from falling off during use and affect the use, low temperature hot rolling process is often used to increase the surface strength of the melt blown cloth. Melt blown cloth is an excellent sound insulation and cushioning material, which is widely used in the fields of construction and automobile manufacturing. Melt-blown non-woven fabric is a non-woven fabric manufactured by the melt-blown process, and it is also a product manufactured directly using the melt-spinning process.