KR101983025B1 - Manufacturing method of Poly(phenylene sulfide) melt-blown nonwoven fabric - Google Patents

Abstract

The present invention relates to a technique for manufacturing an ultrafine melt-blown non-woven fabric, which produces non-woven fabric by the melting temperature at spinning to produce an ultrafine poly(phenylene sulfide) (PPS) melt-blown non-woven fabric, and has excellent physical properties and improved radioactivity by analyzing the same. The non-woven fabric produced according to the present invention has excellent heat resistance, excellent chemical resistance, and high physical properties. In addition, products for various purposes such as high-precision filters requiring heat resistance and automotive interior materials requiring heat resistance and sound absorption due to excellent physical properties such as heat resistance and chemical resistance, heat resistance can be developed.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method for producing a polyphenylene sulfide meltblown nonwoven fabric,

The present invention relates to a process for producing an ultrafine meltblown nonwoven fabric having excellent heat resistance and chemical resistance by using polyphenylene sulfide (PPS), which is a crystalline, thermoplastic resin and an engineering plastic having chemical resistance and insulation properties ≪ / RTI >

According to the present invention, it is possible to produce a nonwoven fabric which can be applied to industrial filters and automobile interior materials which require uniform pore size while maintaining excellent radioactive / continuous radioactivity.

Generally, PPS does not dissolve due to its excellent chemical resistance and is produced by melt-making into fibers, usually by wet-laid nonwoven fabric by wet process or needle fabrication process of staple fiber, thermal nonwoven fabric manufacturing process such as thermal bonding .

The PPS nonwoven fabric thus produced is applied to industrial filters and automobile interior materials which are excellent in flame retardancy, heat resistance and chemical resistance and are required to have high heat resistance, and the demand of PSS nonwoven fabric is increasing.

For industrial filters that require high precision filtration, PP or PET meltblown nonwoven fabric is used as filter media. This is because the filtration efficiency of the filter can be increased and the differential pressure can be lowered. However, dry PPS nonwoven fabrics made of short fibers do not have a uniform pore size unlike melt blown nonwoven fabrics, which makes it difficult to apply filters. In order to solve this problem, attempts have been made to manufacture meltblown nonwoven fabrics and spunbond nonwoven fabrics using PPS at home and abroad, but the development is delayed due to high technical difficulty.

On the other hand, in the production of ultrafine radial type meltblown nonwoven fabric, melt clogging of meltblown devices, leakage of raw materials, and weight deviation occur when spinning the nonwoven fabric, resulting in a product having a high raw material loss rate and low workability, The most important factors to consider in this regard are the selection of the raw polymer (type, physical properties, etc.), the melting temperature, the viscosity, and the design of the spinneret.

The present invention has been made in view of the above points, and an object of the present invention is to propose a method of producing a PPS meltblown nonwoven fabric having pore characteristics of a meltblown nonwoven fabric while maintaining excellent spinnability.

The inventors of the present invention have studied the above points for a long period of time and found that by pelletizing a poly (phenylene sulfide) (PPS) resin into a predetermined size and controlling the melt index and the melting temperature If the microblown process is spun by using the known meltblown method, it has high properties such as heat resistance and chemical resistance, high nonwoven fabric spinnability, excellent productivity and productivity, and can be applied to high precision filters requiring heat resistance among industrial filters , It is possible to develop products such as an engine block insulator, an engine partition, and a heat shield which require heat resistance and sound absorption as automobile interior materials.

Specifically, the present invention provides a method for producing a master chip, comprising: producing a master chip by pelletizing a polyphenylene sulfide (PPS) polymer having a melt index (Melt Index) of 200 to 500 at a pellet chip size of 2 to 5 mm; Applying the master chip prepared according to the above process and drying at 80 to 100 캜 to make the water content less than 200 ppm; Melting and drying the dried master chip at a melting temperature of 320 캜; Characterized in that the cooled and solidified fibers are collected in a collector having a DCD length of 13.5 cm and formed into a web.

That is, in order to secure the physical properties and pores of the PPS polymer after the formation of the nonwoven fabric, the PPS having a low viscosity was selected to improve the radioactivity, and the water content was controlled to be less than 200 ppm and the process of melt- Respectively.

The ultrafine PPS meltblown nonwoven fabric thus manufactured has an average weight of 100 gsm and a deviation of ± 15%, an average tensile strength of 10 N / inch or more, an average pore size of 8 μm or less, and an average fiber diameter of 2 to 3 μm So that it can be applied to industrial filters and automobile interior materials.

According to the present invention, the ultrafine PPS meltblown nonwoven fabric manufactured according to the present invention is excellent in heat resistance and chemical resistance, and can be applied as a high-precision filter requiring heat resistance among industrial filters. As an automobile interior material, an engine block insulator , engine partition, and heat shield.

1 is a schematic diagram of an apparatus for explaining the method of the present invention.

Preparation and compounding of raw materials

The present invention utilizes a poly (phenylene sulfide) (PPS) polymer that can be made into a fibrous web by meltblown radiation. That is, the first step of the present invention is to select a PPS raw material having a low melt index (200 to 500) which is easy to flow during spinning and to dry the PPS raw material in a drier to prevent oxidation of the PPS raw material.

The melt index (MI) of the raw material is an important factor that determines uniform feeding during meltblowing of the raw material during meltblown spinning. When the melt index is high, it is difficult to extrude the raw material in the extruder during meltblown spinning, and the raw material adheres to the screw, which makes it difficult to spin. Therefore, it is necessary to select a material having a low melt index and a small deviation when selecting the raw material . When the melt index of the raw material is large, only the surface of the raw pellet melts and sticks to the extruder screw as mentioned above. The smaller the pellet size of the raw material, the faster the melting in the extruder, the better the flow and radioactivity. In the present invention, it was possible to uniformly feed a raw material having a uniform and small size of about 2 to 5 mm in a spherical shape by spinning. In addition, bubbles are generated at the time of extrusion due to the residual moisture in the raw material after the selection of the raw material, so that it is possible to perform uniform extrusion by removing the residual moisture by drying the raw material.

       On the other hand, ultrafine meltblown spinning can produce nanosized nanofibers of 1 micron level through fine nozzles such as 35 holes, 50 holes, and 100 holes per inch by adjusting spinning conditions. The constituent filament fibers of the nonwoven fabric thus produced have a diameter of about 1 to 10 mu m, and a nonwoven fabric having excellent heat resistance is produced.

Web formation by meltblown spinning and cooling hardening

1, the molten polymer resin, which has been injected into the hopper and melted and compressed through an extruder, is distributed to a distribution plate of a nozzle by a metering pump, and the raw material 3 discharged from the nozzle And a device for winding up the superfine fibers on the conveyor belt provided with the collector 4 and then winding it on the winder 5 is used while drawing the molten polymer with the high temperature and high pressure air, In this case, the meltblown nonwoven fabric is affected by the melt temperature, the discharge air temperature, the discharge air pressure, the cooling air temperature, the distance (DCD) of the conveyor belt from the nozzle, Belt distance (DCD) and melt temperature. That is, when all other conditions are the same, the temperature of the polymer (1) melted in the metering pump and the nozzle distribution plate after melt compression, the viscosity of the molten resin is improved at a proper temperature of the raw material, The resin is uniformly distributed and the radioactivity improves. As a result of the study by the present inventors, it has been confirmed that the distance (DCD) of the conveyor belt from the nozzle greatly affects the weight deviation of the produced nonwoven fabric.

The present invention also includes a step wherein the meltblown fibers are cured by the cold air supply device (2) before reaching the collector (4). Thereby, the fibers are cooled and cured to improve the morphological stability. Here, although the low-temperature air current is brought into contact with the spinning fiber, the meltblown fiber is not completely cured because the meltblown fiber falls down to the bottom at a high speed. Approximately 10% to 20% of the fibers are collected in the downward collector together with the melted brown cured fiber, and the entire composite fiber evolves into a fibrous web. The temperature of the cooling air stream varies depending on the discharge speed and the like, but is about 5 to 25 占 폚.

Experimental Example 1

Poly (phenylene sulfide) (Celanese Fortron) was used as the raw material of the ultrafine meltblown nonwoven fabric, and raw materials having a pellet size of 2 to 5 mm were selected. The selected PPS raw materials were adjusted to a water content of 200 ppm or less after drying temperature of 90 ° C and drying time of 8 hours. The ejection air pressure was radiated under the following conditions using a 4 to 6 psi, 35 hole / inch nozzle.

Melting temperature 300 ℃

DCD: 9cm

Cooling air temperature 10 ° C

The basis weight of the manufactured nonwoven fabric: 100 g / m ²

Experimental Examples 2 to 16

The raw materials were the same as in Experimental Example 1, and the spinning conditions were as follows.

The physical properties of the PPS nonwoven fabric produced by the above Experimental Examples are summarized in the following table.

 - Poly (phenylene sulfide) (PPS): Melt Index 200-500 (Celanese Fortron)

 (1) The nonwoven fabric weight was measured by the KS K 0514 method.

 (2) The nonwoven fabric strength was measured by the KS K 0521 method.

 (3) Elongation ratios were measured three times each by the cut-stip method (tensile tester; Instron 4467, Instron USA).

(4) Air permeability was measured three times each using a nonwoven fabric of 7 cm * 7 cm using an air permeability measuring instrument (FX-3300, measuring area 38 cm ² , measuring pressure 125 Pa)

 (5) Fiber diameter was measured by KS K 0463 method.

 (6) The pore size was measured in a dry up-wet up sequence using a nonwoven fabric of 3 cm * 3 cm with a PMI (Porometer (CFP-1200AE)) apparatus using a Galwick apparatus.

  (7) Continuous spinnability was measured at 100% of full drum minus the number of nozzles replacement without nozzle replacement in the production of nonwoven fabric.

As shown in Experimental Examples 1, 2, 3 and 4 above, when the PPS spinning melt temperature is 300 ° C to 317 ° C, the raw material partially melts and shot and drop phenomenon occurs and the spinning is impossible. In order to improve this, the melting temperature was raised to 318 ° C or more, and the radioactivity and productability were improved. However, the flowability was poor and the continuous radioactivity was difficult. Therefore, in order to increase the flowability of the raw material, the spinning test was conducted by raising the melting temperature up to 330 ° C. As a result, when the melting temperature was 330 ° C (Experiment 9), a malfunction occurred due to high temperature, The phenomenon partially occurred.

       In order to improve the average tensile strength, the pore size and the fiber diameter in Experimental Example 10, 11, 12, and 12, the spinning melt temperature was determined to be 320 deg. C (Experimental Example 7) 13, 14, 15, and 16, respectively.

       In Experimental Examples 10, 11, 12, 13, 14, 15, and 16, the spinning melt temperature was fixed at 320 ° C. and the DCD length was controlled to be between 10 and 30 cm. In case of DCD length of 10, 12, 13.5 cm, the weight deviation was the lowest, so that the uniform nonwoven fabric was emitted. However, in case of DCD length of 10 and 12 cm (Examples 10 and 11), the fiber diameter was about More than twice as high. In order to confirm the fiber diameter, pore size and continuous radioactivity, the DCD length was adjusted to 14-30 cm (Experimental Examples 13, 14, 15, 16) to conduct the radiation test. As a result, it was confirmed that when the DCD length is increased to 14 cm or more, the weight deviation becomes very high and the radioactivity becomes low.

       Therefore, the PPS spinning conditions satisfying all of the desired physical properties (weight 100 gsm deviation 15%, average intrinsic strength 10 N / inch, average pore size 8 μm or less, average fiber diameter 2 to 3 μm) of the ultrafine PPS meltblown nonwoven fabric It is considered to be most appropriate to radiate at a spinning melt temperature of 320 ° C and a DCD length of 13.5 cm.

Claims (2)

(S1) preparing 2 to 5 mm pellets of a polyphenylene sulfide (PPS) polymer having a melt index (Melt Index) of 200 to 500;
(S2) drying the pellet at 80 to 100 DEG C to make the water content less than 200 ppm;
(S3) melting and melting the dried pellets at a melting temperature of 320 ° C;
(S4) curing the meltblown fiber; and
(S5) said cooled, solidified fibers are collected in a collector having a DCD length of 13.5 cm and formed into a web,
The ultrafine meltblown yarn is produced by making fine nano-sized fine fibers of 1 micro-level through fine nozzles of 35 holes, 50 holes or 100 holes per inch by adjusting the spinning conditions. 1 to 10 mu m,
After the raw material is injected into the hopper, the molten polymer resin melted and compressed through the extruder is distributed to the distribution plate of the nozzle by the metering pump, and the molten polymer discharged from the nozzle is extruded and miniaturized by high temperature and high pressure air, While winding the superfine fibers on a conveyor belt equipped with a collector, and then winding the fibers on the winder,
After the melt extrusion, the polymer melted inside the nozzle distribution plate is uniformly distributed to the distribution plate of the nozzle at the proper temperature through the metering pump,
Curing the meltblown fibers by a cold air supply device before reaching the collector so that a low temperature stream is brought into contact with the spinning fibers such that the meltblown fibers fall down to the bottom at a high speed, And 10 to 20% of the fibers are collected in a downward collector together with the fibers cured in a molten state, so that the entire composite fibers are evolved into a fibrous web. The method according to claim 1, wherein the step of curing the melted blended fiber is performed at 5 to 25 ° C.

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