Biodegradable electret melt-spurt filtering material and production method

Abstract

The invention discloses a biodegradable electret melt-spurt filtering material with the advantages of energy-saving, consumption reduction, 100 percent degradation in the natural environment and high filtering efficiency and a production method. The biodegradable electret melt-spurt filtering material is prepared form PLA slices with melting index of 500-800g / 10min (2.16kg, 230 DEG C) by the process steps of charging, screw rod melting extrusion, die head spinning, drawing, wet formation and high-voltage electric field electret. In the step of screw rod melting extrusion, the temperature of screw rods in each region is between 185 and 215 DEG C, the temperature of a filter is between 215 and 220 DEG C, the temperature of a metering pump is 215 DEG C and the pressure of the screw rod is 25bar; in the step of die head spinning, the temperature of the die head in each region is between 210 and 220 DEG C; in the step of drawing, the air pressure of the drawing is 0.75bar and the air temperature of the drawing is 220 DEG C; in the step of wet formation, the negative pressure of the absorption is 0.036bar, and the distance between a wet forming machine and a die head spinning jet plate is 100mm; and the step of high-voltage electric field electret is to enable a PLA fiber web to pass through a 50kV electric field.

Description

Technical field: [0001] The invention relates to an electret melt-blown filter material and a production method, in particular to a biodegradable electret melt-blown filter material and a production method that can save energy and reduce consumption, can be 100% degraded in the natural environment, and have high filtration efficiency. Background technique: [0002] Electret melt-blown filter material is one of the main materials in medical protection, especially during the ravages of epidemic viruses, this material is widely used. Existing electret melt-blown filter materials mainly use high-melt index PP (polypropylene) as raw material, and are made by melt spinning and high-pressure electret methods. There are following problems: PP is made of petrochemical raw materials, and petroleum It is also a non-renewable resource, which cannot meet the requirements of energy saving and consumption reduction; at the same time, PP is also a non-degradable material. After the filter p...

AI Technical Summary

Problems solved by technology

Existing electret melt-blown filter materials mainly use high-melt index PP (polypropylene) as raw material, and are made by melt spinning and high-pressure electret methods. There are following problems: PP is made of petrochemical raw materials, and petroleum It is also a non-renewable resource, which cannot meet the requirements of energy saving and consumption reduction; at the same time, PP is also a non-degradable material. After the filter product produced is discarded, it is not easy to degrade in the natural environment, and it needs a certain cost to dispose of it, resulting in economic waste and environmental pollution

[0004] Due to the complex production process of electret melt blown filter materials, including feeding, screw melt extrusion, die spinning, drawing, etc. to form ultrafine fibers, and then bonded and cooled on the forming mesh curtain to form melt blown nonwovens cloth, and then electret in a high-voltage electric field. The process parameters of each step are very important. Therefore, there has been no report on the production of electret melt-blown filter materials using polylactic acid as a raw material so far.

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