PTFE synchronous multi-layer slitting and multi-layer co-extrusion extrusion device

Abstract

The invention relates to a polytetrafluoroethylene synchronous multilayer cutting and multilayer co-extrusion device. The polytetrafluoroethylene synchronous multilayer cutting and multilayer co-extrusion device is characterized by comprising an injection cylinder, a plunger, a gate and a plurality of layered cutters, wherein an injection cavity is formed in the injection cylinder, the injection cavity is composed of two cavities, the cross section of one cavity is rectangular, the cross section of the other cavity is in a V shape, a plunger opening is formed in the upper end of the injection cylinder, the plunger opening is communicated with the cavity of which the cross section is rectangular, an extrusion opening is formed in the lower end of the injection cylinder, and the extrusion opening is communicated with the cavity of which the cross section is in the V shape; the lower end of the plunger is inserted into the cavity of which the cross section is rectangular through the plunger opening, and the gate is arranged on the injection cylinder; the plurality of layered cutters are arranged at the extrusion opening, and the plurality of layered cutters are positioned in the cavity of which the cross section is in the V shape. The extrusion device has the advantages of simple structure and high production efficiency. A polytetrafluoroethylene grating hole multilayer film laminated body produced by the extrusion device has the characteristics of high collection efficiency, large air permeability, high strength and low consumption.

Description

technical field [0001] The invention relates to a polytetrafluoroethylene synchronous multi-layer slitting and multi-layer co-extrusion extrusion device. Background technique [0002] Usually polytetrafluoroethylene is biaxially stretched into a microporous membrane to achieve a suitable filter medium, which should have a high purification efficiency for trapping fine particles and a low gas permeation resistance with a large air flow rate, but when the pore size is made into When it is very small to achieve high capture efficiency, the resistance of the gas increases with the decrease of the pore diameter, and the gas flow rate decreases. Conversely, increasing the pore size reduces the gas resistance, and the capture efficiency decreases with the increase of the pore size. Collection efficiency and high air permeability, when the pore size and porosity are constant, the smaller the film thickness is, the smaller the gas permeation resistance is, and the flow rate increases...

AI Technical Summary

Problems solved by technology

However, the microporous membrane with a small film thickness is deformed due to the pinholes generated during stretching and the pressure applied during filtration, thus displacing the pores or breaking the membrane and failing to function as a filter medium. Such a thin microporous membrane (typically 2-10um) is so poorly processed that it is easily damaged when processed into a filter assembly or secured to a backing

In addition, in order to obtain high collection efficiency and large air flow, the pore size distribution should be very narrow and the porosity should be high, but it is difficult to achieve it by applying the current general stretching process

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