Melt-blown polypropylene composite material, and preparation method and application thereof

Abstract

The invention discloses a melt-blown polypropylene composite material. The composite material comprises, by weight, 87-98 parts of polypropylene resin, 2-13 parts of long carbon chain nylon resin and0.1 to 5 parts of an electret agent. Firstly, by means of the low compatibility of polypropylene resin and the long carbon chain nylon resin and the relatively high crystallization speed of the long carbon chain nylon resin, thick long chain nylon resin filaments and thin polypropylene resin filaments can be obtained after melt-blowing filamentation, and the filtering efficiency can be improved while the filtering resistance is reduced; secondly, the long carbon chain nylon resin contains polar amido bonds, so that the dispersion effect of the electret is improved after the long carbon chain nylon resin is easily combined with the electret, meanwhile, the nylon fibers can be subjected to electret polarization and cooperate with the electret agent to improve the filtering efficiency; and thirdly, due to the existence of the long carbon chain nylon crude fiber yarns with higher strength, the breakage probability of the melt-blown cloth in the winding process can be reduced.

Description

technical field [0001] The invention relates to the technical field of polymer materials, in particular to a melt-blown polypropylene composite material and its preparation method and application. Background technique [0002] Since the beginning of 2020, the novel coronavirus pneumonia epidemic has been raging around the world, and the situation of "hard to find a cover" has been staged in many overseas countries. The main structure of the protective mask for preventive use consists of three parts: the surface anti-humidity layer (S layer), the middle filter adsorption layer (M layer) and the inner skin layer (S layer), and the raw material is polypropylene. The M layer consists of one or more layers of electrostatic melt-blown nonwovens, which play a core protective role. It is called the "heart" of medical and N95 masks. This middle layer material is a melt-blown polypropylene composite material. [0003] At this stage, the improvement of melt-blown polypropylene composi...

AI Technical Summary

Problems solved by technology

Although the strength of PA66 melt-blown non-woven fabric is much greater than that of polypropylene melt-blown non-woven fabric, it has the following defects: 1. PA66 is a short carbon chain nylon, and the high density of amide bonds makes the water absorption of the fiber filaments strong, resulting in its post-electret charge It is easy to dissipate, which is not conducive to maintaining the filtration effect; 2. The temperature of the die opening and the dragging air need to exceed 300°C

At this stage, the material of melt-blown cloth for masks is mainly melt-blown polypropylene composite material. However, since polypropylene is a non-polar resin, the combination with the electret agent is weak, which will cause the electret agent to be trapped in the polypropylene fiber filaments. The uneven distribution of the filter is also not conducive to the retention of static electricity, resulting in large fluctuations in filtration performance

At the same time, due to the low strength of the fibers formed by the degraded polypropylene resin, it is easy to be torn during the process of winding, cutting, and sewing into a mask, which not only leads to waste of melt blown cloth, but also delays the production cycle

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