JPS58109619A - Ultrathick aromatic polyamide fiber, its aggregate and preparation thereof - Google Patents

Abstract

PURPOSE:To obtain ultrathick aromatic polyamide fibers, by melt spinning an aromatic polyamide polymer through a mesh-like spinneret having a specific porosity. CONSTITUTION:An aromatic polyamide polymer powder is fed from the opposite side of an extrusion surface of a mesh-like spinneret having >=10% porosity (alpha) expressed by the formula[(Va] is the apparent total volume of the mesh-like part of the spinneret in unit area; (Vf) is the total volume of the mesh-like member surrounding the pores in unit area of the mesh-like part of the spinneret] and adjacent many pores and melt extruded through the spinneret while supplying heat from partition members of the spinneret to give the aimed ultrathick fibers having 100-100,000 average deniers.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a new heat-resistant aromatic polyamide fiber and a new and economically advantageous method for producing the same. A fiber produced by melt-molding aromatic polyamide, and relates to a very thick aromatic polyamide fiber and a manufacturing method thereof.

Aromatic polyamides are heat-resistant and flame-retardant polymers that have been widely proposed, particularly polymetaphenylephamide, for example. m680 [Depot.

It is commercially available in large quantities as a fiber under the names oonJ (manufactured by Teijin Ltd.) and oonJ (manufactured by Teijin Ltd.). This fiber has a flexibility comparable to that of conventional organic fibers, and has a visceral oxygen index (Lo) of 27. Melting point is 400-410
It has flammability and heat resistance with a decomposition starting point of approximately 460°C, making it useful as fireproof clothing, rag filters, and insulating materials. (11)] This fiber is commercially available as a fiber with the name of polymetaphenylene iso-7 talamide fiber, has strong flame resistance and heat resistance, and has high strength, high fiber content, high gloss content, and is suitable for composite materials. , ropes, etc.A variety of modifications (copolymerization, blending, etc.) have been carried out on these three types of aromatic polyamides, and compositions suitable for each purpose have been studied.

Generally, aromatic polyamides have a high melting point, which is close to the decomposition initiation temperature, so it is impossible to melt-extrude them using conventional melt-spinning equipment. Therefore, it is customary to dissolve the polymer in a solvent and perform wet or dry spinning, and the solvent may be an aprotic polar solvent such as dimethylformamide, dimethylacetamide, or M-methylpyrrolidone alone or in combination with lithium chloride.

Periodic table of calcium chloride, etc.! metal parts of the group or the group
It is known to use a mixed solution with a genide salt, sulfuric acid, chlorosulfuric acid, heptathonic acid, trifluoroacetic acid, and the like. For industrial use, equipment to recover or neutralize these solvents is required, and the amount of solvent used per unit weight of the polymer is usually 3 to 20 times the weight of the polymer, so spinning It requires extremely large collection equipment and processing equipment compared to the equipment itself. Moreover, the cost of the solvent that cannot be recovered is added to the cost of the TT fiber.

For these reasons, Moshiso Opoly! It is obvious that it is more advantageous to adopt the melt spinning method than the solution spinning CII method, dry method, or semi-dry and semi-wet method, if it is possible to melt-spun -. This also applies when performing the Isame Zerimar 〇jusha inside **. This is because the process is much simpler if the cough polymer is separated (precipitated) from the solution tube and then melt-spun, compared to solution-spinning.

In addition, in the case of solution spinning, if the target fiber becomes thick, it becomes very difficult to extract and remove the agent sufficiently. For example, when dry-spinning a solution of polymetha-7-ethylene isophthalamide dissolved in dimethyl chloride/calcium chloride, the solvent in the outer skin of the fiber preferentially escapes, causing the outer skin to coagulate into a rough texture. , which seriously inhibits the diffusion of the solvent in the core. Therefore, it becomes more difficult to extract and remove the solvent from the core as the fiber becomes thicker, and it is necessary to make the spinning tube extremely long. Or Polymeta 7
The same is true when wet-spinning a solution of ethylenic inophthalamide in N-methylpyrrolidone solvent, which requires extremely long coagulation baths and water washing baths.

Even more unfavorably, fibers with a so-called skin-core structure, in which the structures of the outer skin and core are extremely different, are obtained, which reduces the flexibility of the fibers, and makes it difficult to compare normal ultra-thick aromatic polyamide fibers. I couldn't get it.

Furthermore, in the conventional method of one-solution spinning, the cross-sectional shape of the fibers obtained is almost a perfect circle, and the cross-sectional area is almost constant in the axial direction, so it is difficult to create a texture similar to that of natural fibers. Ta.

The present invention aims to solve these problems. That is, an object of the present invention is to provide extremely thick aromatic polyamide fibers and aggregates thereof that have not been obtained hitherto. Another object of the present invention is to provide a method for producing extremely thick aromatic polyamide fibers by a highly productive melt spinning method that does not require complicated procedures such as solvent treatment. Furthermore, another l in Honji @
The purpose of this is to provide the largest aromatic polyand fiber and so-O fiber aggregates that have properties similar to natural fibers with varying cross-sectional shapes and cross-sectional area sizes. The purpose of this project is to carry out intensive research for the above-mentioned purposes, and to obtain extremely large aromatic polyamide fibers with a round shape similar to natural fibers and their aggregates using a novel melt-spinning method with high productivity. I found out and left the original W14K11.

In other words, the present invention provides very thick aromatic polyamide fibers comprising at least one type of aromatic polyamide, characterized in that the average fineness (5. It relates to fiber aggregates, and the following formula (f) Va - Vf, = -X I OO... - (W) Va using a mesh-like spinneret having a large number of closely spaced 1AllII having a porosity of about 10 or more,
Powder of a coated aromatic polyamide polymer is supplied to the side opposite to the discharge direction of the spinneret, and the powder is supplied while supplying heat from the heat-generating partition member of the mesh-like spinneret. The mosquito fluid is melted and squeezed out from the numerous slits surrounded by the partition member, and at this time, a cooling fluid is supplied to the discharge surface of the spinneret and its vicinity. Wrinkles due to cooling #l1
1. The solution extruded through 1.0% converts the melt into a large number of separated fibrous rivulets and solidifies within a time during which the molten polymer does not substantially lose its ability to form a mold. The present invention relates to a method for producing an extremely thick aromatic l-aryamide fiber aggregate.

The present invention will be explained in more detail below.

[Extremely thick aromatic polyamide fiber of the present invention and aggregate thereof]

The novel ultra-thick aromatic polyamide fibers and aggregates thereof of the present invention are greatly different in form from conventional aromatic polyamide fibers.

That is, the novel tl group polyamide fiber of the present invention and its aggregate are characterized by being extremely thick, which could not be obtained conventionally.

In this IM@, the extremely thick aromatic polyamide fiber and the extremely thick aromatic fiber aggregate are defined by their average fineness (D・)
is l@@Nl@false ooo denier O range, preferably l
oo~la@Godea-At'O9 [The t's in the box are. If the average fiber*(D・) exceeds 10 to 4 deniers, it becomes difficult to continue stable spinning, so it is not very preferable. The cross-sectional area of the fiber has irregular and periodic changes in the size of the fiber, and the coefficient of variation of the cross-sectional area within the fiber [cv (F5)] is in the range of α05-LO according to the definition described below. The characteristic of conventional fibers is that 0V (F) is αO
less than S.

This aV(3) refers to the fiber in its length direction k, for example, 1
When cutting at the interval, the size of each cross-sectional area O fluctuates randomly, and the fluctuation of the size of the cross-sectional area has an irregular period, and the width of the fluctuation is statistical. means that it is within a certain range.

This new ultra-thick aromatic polyamide fiber is
In other words, the cross section is non-circular, and the cross-sectional area has large changes in irregular periodic intervals along the length of the fiber.
In addition, it is characterized by having four new changes in the shape of the surface.

Further, in the novel ultra-thick aromatic polyamide fiber aggregate of the present invention, each fiber thereof has the above-mentioned characteristics, and at any position of the aggregate consisting of a large number of fibers constituting the aggregate, It is characterized in that the size of the cross-sectional area of each fiber when the bundle is cut is substantially randomly different.

What is the intrafiber cross-sectional area variation coefficient [CV (to)] referred to here?
It shows the variation in the fineness in the length direction (axial direction) of the fibers, and selects an arbitrary S (to) of 01 points for any number of O fibers in the fiber aggregate, and calculates it at intervals of 1111 intervals. The size of the cylinder volume O is fixed by microscopic observation, and its SO
The average value (τ) of the 30 cross-sectional areas and the standard deviation (σm) of the 30 OWR areas can be calculated using the following formula.

-MuaVke＞--=-Mumoto@O extra-thick aromatic polyamide fibers , 轡に1・・〜a1、中゛-1〜aselli
IO is also open.

Another feature of the novel ultra-thick aromatic polyamide fiber of the present invention is that the cross section is non-circular, and the cross-sectional area of the iron fiber has an irregular periodicity along the length direction. There is a change in the cross-sectional shape along with a change in the cross-sectional shape.

The degree of non-circularity of the cross-sectional shape of the fiber is determined by the irregularity coefficient expressed as the ratio (D/d) of the maximum spacing between the circumscribed 2,000-line lines (b) and the minimum spacing between the outer lI2 parallel lines (e). can be shown. The extra-thick aromatic boria fiber of the present invention has a shape coefficient (D/l) of at least Ll, and most of them have at least L2.

Furthermore, the extra-thick aromatic polyamide fiber of the present invention is characterized in that the above-mentioned deformation coefficient (D/(1)) changes by KfB in the length direction of the fiber. Maximum irregularity coefficient [(D/6) hidden X] and minimum irregularity coefficient [(D/
d)i]
)wax-(D/d)si) #has the characteristic of being at least aoi, preferably at least α1.

Furthermore, regarding the novel ultra-thick aromatic boria zeta fiber aggregate of the present invention, it is possible to cut the mosquito aggregate in a direction perpendicular to the fiber axis at any position of the aggregate consisting of a large number of fibers constituting the aggregate. The variation in the cross-sectional area of each line in the case is expressed by the intra-bundle fiber cross-sectional area variation coefficient [OV] and is in the range a1 to LS!
and 41KOV(4) is in the range I of a2~1! There are 91 major features that make it one of the best.

This ay(A) is calculated by randomly extracting Kl@0 fibers from the above aggregate, making it into a bundle with nine springs, and forming a wrinkled bundle in the direction perpendicular to the fiber axis at an arbitrary position O. Cut round O
Examine the cross-sections under a microscope* and measure the extent of each cross-section.
It is natural to find the average value ('i) and the standard deviation (gB) of its *oO@O cutoff product, and calculate it using the following formula.

The ultra-thick aromatic boria electrode fiber assembly of the present invention, further,
It is assumed that the cross section of each fiber when cutting the mosquito bundle in a direction perpendicular to the fiber axis at any position of the bundle is substantially different in size and shape at random. There is.

That is, when the bundle is cut, the cross section of each fiber is non-circular, and each cross section has the above-mentioned deformation coefficient (D/(1) of at least 4tt, and most of them have at least t2. .

Furthermore, the maximum deformation coefficient when at least 30 cross sections of the iron fiber bundle are randomly extracted' [(D/6)
mpy] and the minimum irregularity coefficient [(D/d)i].
mx −(D/61m) is at least aos;
It is preferably at least -at.

The aromatic polyamide polymers targeted in the method of the present invention have the following formulas (1), (1), @-O-R'-OM
@bone...beak (1)H + N -x@-violet-...(2)-〇-R”
-M-... (to) Selected from the group consisting of: 9 A polymer consisting essentially of at least one type of 0 repeating units;
Generally, aromatic boryamide 19 is also referred to as fully aromatic boryamide.

R'', R that satisfies the above formulas (1), (1) and @
R and R may be the same or different divalent groups, and their total weight is at least 1,000, preferably at least 10, aromatic groups. The aromatic group referred to here means a group having a usual benzene nucleus such as benzene, naphthalene, anthracene, etc.

In other words, examples of such aromatic groups include paraphenylene group, metaphenylene &, LS-f butylene 1,26-naphthylene group, 13'-, 44'-, 14'-diphenylene group, &3'- ,44'-,! Examples include a 4'-diphenyl ether group, a baraxylylene group, a metaxylylene group, and a para(meth)methylphenylene group.

A preferred aromatic polyamide in Honjitsu 1jl is polyparaphenylene iso7taluride.

Polymeta-phenylene-7-thalamide, poly-meta-phenylene-phthalamide, bo-IJ-Ls-naphthylene-7-thalamide, poly-m-4'-diphenylene-7-thalamide, polymeth-7-lylene isophthalamide or monopolymer copolymer etc. can be opened. Particularly preferred aromatic boria compounds include polymethaphenylene isophthalate and polymethaxylylene isophthalate.

Examples include copolymers (metaphenylene/cyanine, ino-7 thalene, meta-aminobenzoic acid chloride), and the like.

In the aromatic polyamide polymer of the present invention, the moldability can be improved by introducing a flexible chain group such as the 11r formula (1), (1), @OR'', R'' and V part Km aliphatic chain. However, the ratio of the groups is R1, H*
and R” exceeds the go type weight of the 0 go needle.

This is not preferable because properties such as heat resistance, which are important characteristics of aromatic polyamides, deteriorate.

In the novel ultra-thick aromatic boria ζ-d fibers and fiber aggregates thereof of the present invention, partial crosslinking of the polymer may be included. This pigeon house also has additional advantages such as improved heat resistance of the fibers.

The novel ultra-thick aromatic boria fibers and fiber aggregates thereof of the present invention have been described above, and the manufacturing method thereof will now be described in detail.

[Method for producing ultra-thick aromatic bolioid fiber I/aI & shell O of the present invention]

The method for producing a novel ultra-thick aromatic polyand fiber aggregate according to the present invention is as follows: (1) A large number of adjacent jIl! (2) supplying powder of the aromatic boria ξ-dopolymer to the surface opposite to the discharge surface of the spinneret; (3) using the mesh-like spinneret having a Heat is supplied from the partition member generating heat to the powder t*a*, and the melt is extruded through the multiple gaps separated by the partition member, (4) At this time, the spinning process is performed. (6) The melt extruded through the slit is collected while cooling the melt by supplying a cooling fluid to the discharge surface of the melt and the vicinity thereof of the nozzle, and (6) the melt polymer is formed into a molded cedar in a comprehensive manner. This method is characterized in that the melt is divided into a large number of pieces into #1I61 and solidified within a period of time without losing its properties.

As explained above, in the method of the present invention, the discharge surface of the conventionally known ordinary thermoplastic polymer melt is a smooth surface, and the discharge holes (orifices) of the II#lI liquid are arranged in a regular manner. This is fundamentally different from the method of manufacturing fibers in which the chain melt is extruded through independently drilled spinnerets.

The spinneret used in the present invention has a close majority omvs defined by the porosity←)O value as shown in the above formula <1). The mesh-like part of the spinneret in the formula (W) K that defines the porosity, the mesh-like part, and the mesh-like part of the spinneret.

The spinneret used in the present invention has a number of closely spaced pores defined by the porosity value 119. The shape of the slit or the shape of the partition member that defines the slit may be any shape.

The mesh-like spinneret used in the present invention is as follows.

Therefore, for example, it may be circular, circular, triangular, a-gonal, or other polygonal shape, or the partition member defining mIm may have a concave or convex shape, but may not have a 4-sided shape.

Figures t-aK of the accompanying drawings illustrate an example of a mesh-like spinneret used in the present invention. The illustrated light mesh spinneret is a plain woven wire mesh. 11g1
t-blc is an illustration of a cross-sectional view of the wire mesh in FIGS. 1-5L.

The plain weave wire mesh shown in the figure has slits in the form of rectangular tubes.
The partition member between the adjacent gaps has a concave portion so that the melt extruded from the adjacent gaps can pass through each other.

FIG. 2-ILK of the accompanying drawings illustrates another example of a mesh-like spinneret used in the present invention. The illustrated mesh-like spinneret is an etched perforated plate in which a large number of 0III- patterns are formed on a thin metal plate using a precise etching technique. In this etched perforated plate, the WAN has a roughly triangular shape, and as can be seen from the nine sectional views illustrated in FIG.

It may be a mesh-like spinneret used in the present invention, or other twill wire mesh, or it may be a thin, thin sintered body in which a large number of microscopic metal spheres are sintered to form a large number of slits.
good. Also, the *partition existing in the narrow gap> member is an etched perforated plate with a recessed part, which is effective.

In the present invention, these MEC-like spinnerets can be used not only alone, but also in combination and laminated.

FIG. 3 of the accompanying drawings shows a cross-sectional view of a MEC-like spinneret used in the present invention, which is constructed by laminating two sheets of Heishikai net.

Among these spinnerets, according to the present invention, it is preferable that the spinneret discharge WK is partitioned by a narrow partition member having uneven portions and has a large number of slits, and has 0 slits. A V5-shaped spinneret with a structure such that the melt extruded from III can communicate with the SS* liquid extruded from another gap adjoining it through the recess of the partition member is used.

In the above formula expressing the porosity that defines the MEC-like spinneret used in the present invention, Va is the total volume of the spinning metal (O mesh shape) (0 units).
, vt #i is the total volume occupied by the partition member, excluding 1 and 1, under single position stacking of the mesh-like portion of the spinneret.

As can be seen from the illustrations in FIG. 1-a and FIG. The volume of the area enclosed by the area (l-) is calculated using the above formula (V
) is defined as the total volume (Va) above.

In the case of a laminated MEC-like spinneret as shown in Fig. 3, the total volume (Va) of the spinneret is
It is easy to understand that this is required.

To find Va for an actual mesh-like spinneret, k is determined by measuring the thickness of the mesh-like spinneret using a dial gauge with a contact surface of lai.Va
can be easily determined.

(9) In order to determine Vft for a certain mesh-like spinneret, it is sufficient to cut the mesh-like spinneret into a predetermined area, immerse it in a liquid, and measure the increased volume at that time. The value of this increase converted into 9-volume tube mesh-like spinning metal 1 - Todoroki becomes Vf.

The porosity (cl) expressed by the formula (f) of the mesh-like part used in the present invention is approximately 10-
or more, preferably about 2s to about 90 capsules.

Further, according to the present invention, the MEC-like spinneret used in the present invention preferably has a length of about 5 or more, more preferably about 10 to about 1,000 lag.

It has a sliver of intelligence.

The MEC spinneret used in Honpatsu 11 is approximately 1
The thickness is less than or equal to 0, more preferably about a1 to about Is, particularly preferably about a2 to about 2.

The spinneret having the structure achieved in the present invention is such that the polymer melt in the forming area 0 IFK is discharged from the spinneret.
It is preferable that the average distance (p) of the cabinet is in the range of ch, os to 41M.

In particular, the forging area is Kltf! According to the rules.

(1) The average distance between the discharge ports) is in the range of a03 to 4■, (2) The average peak height i) is α01 - lII
Surrounded by.

(3) Average mountain height (it ranges from α02 to LSI!II and (4) the average mountain height and the average mountain height (a't are narrowed by (h) / (a) and range from α3 to 50) It is advantageous to use a spinneret with a discharge surface having a range of fine asperities and a large number of slits.

The above-mentioned molding area, average distance between discharge ports (p), average peak height (i), average peak height (I), and slit are each defined by the following explanation.

The average narrow gap distance (p), average peak height i), average peak height (i), etc. defined in the present invention are all values determined based on the concept of geometric probability theory, and the shape of the surface of the forming area is For things that are geometrically obvious, they can be calculated mathematically using the definitions and methods of integral geometry.

For example, regarding the molding region of a die in which a sintered body of a spherical shape with radius r is a close-packed term, the theoretical KB-VTr * 5-
It becomes ヱr, ma-÷r.

In this way, it can be determined theoretically for a case where the cap surface is composed of a set of uniformly geometrically shaped noses, but for a case with a microscopically non-uniform surface shape, it is possible to determine the Alternatively, ps h *'l can be determined from K by cutting at a right angle, or by making a mold of the surface of the cap using a material that is easy to cut, cutting it, and actually measuring it. For actual measurements, set the origin at the center of the forming area, which is the surface of the forming area that is macroscopically uniform, and take six cross-sections around the forming area to obtain approximate Kp and h.

d can be obtained, and this is sufficient for practical purposes.

The forming region refers to a region where a fiber bundle having a substantially uniform density is formed in a spinneret for discharging the molten polymer and spinning and forming a very thick fiber bundle.

Book vhf! When the molding area of the mouthpiece is cut at right angles to its average plane (a smooth virtual surface that is macroscopically understood by averaging minute irregularities) (hereinafter, this cross section will simply be referred to as the molding area cross section). ), refers to the first minimal visible flowing part of the flow path in which the polymer can be discharged and flowed, when viewed from the surface side of the molding area at right angles to its average plane.

FIG. 4 shows a schematic enlarged view of an arbitrary cross section in the generalized molding region of the present invention. In this FIG. 4, the Mu1 and Mui+1 portions are l18iIll.

9, the distance between the center lines of any adjacent slits M1 and M1+10 is called the distance P1 between llA181,
The average of Pl in all cross sections is the average narrow gap distance p
It is defined as

The partition member of the spinneret used in the present invention is in a state in which heat is generated to melt the powdered polymer supplied as described above.

In order to generate heat from the partition member itself, a wrinkled partition]
A method in which the member is heated by passing an electric current through it (current heating method), a method in which a high-frequency electric field is applied and heated by the Tsuba Dokashima method, a method in which the partition member is constructed of thin tubes and a heat medium is flowed through the tube to heat the member (thermal fluid heating method). heating method) etc. are advantageously employed.

Materials that can be used in the current heating method and induction heating method include platinum, gold *, steel, titanium, vanadium, tungsten,
Iridium, molybdenum.

Palladium, iron, nickel, chromium, cobalt, lead,
11 metals such as zinc, bismuth, tin, aluminum, etc.
Stainless steel, nichrome.

Alloys such as tantalum, brass, brass bronze, and dieralmin, graphite, silicone, and germanium.

Selenium, tin oxide, indium oxide^, *iron oxide.

List of inorganic compounds that mainly exhibit semiconductor properties such as nickel oxide, and organic compounds that exhibit semiconductor properties such as polyacetylene and polyphenylene, 1 (1" to 10Ω country level 0
A material having a specific resistance is formed in the spinneret, and a round material is advantageously produced.

The nine spinnerets explained in the attached drawings, FIG. 11, FIG. 2, and FIG. 3 are all electrically conductive and meet the purpose K of the present invention. A conductive structure in which alumina, zirconia, or other metals are vapor-deposited onto ceramic fibers such as alumina or zirconia, and a conductive cap structure is formed by pressure molding.A porous ceramic plate is immersed in a graphite particle dispersion. Deposited electrically conductive mesh-like spinneret structures are mentioned, and various other possible structures have been modified.

It can be implemented.

In the case of the electrical heating method, the conductive mesh-like spinneret thus obtained is usually heated under an electric field of 1 to several hundred V/d, a1 to several hundred V/d.
A current of several cm is applied and a watt density of from al to several thousand W/ai is used, but these values may vary depending on the purpose of use.

The conductive mesh-like spinneret for the current heating method is attached to the extruder, and should be installed so that the desired current flows through the conductive member V:L-shaped spinning die. The conductive mesh spinneret and the extrusion lateral tube can be insulated, and the extruder and the conductive mesh spinneret can be electrically connected to separate the current flowing across the extruder and the current flowing through the conductive mesh spinneret. It is also possible to obtain the desired performance by appropriately distributing it.

Insulating materials used to insulate the conductive spinneret and extruder are general ceramic plates, silica, alumina,
A combination of inorganic adhesives such as zirconia can be used.

On the other hand, when heating a conductive messier-like spinneret as described above by an induction heating method, a coil is generally arranged approximately parallel to the spinneret, and a nearly perpendicular magnetic field is applied to the spinneret. Eddy currents are generated above and Joule heat is generated.

If the heating frequency is selected as Takaoka #lK, the eddy current will not penetrate shallowly due to the skin effect, and local heating can be performed only on the surface.

According to the thermal properties of the aromatic polyamide polymer to be molded and the material and shape of the equipment, the optimum state can be obtained by appropriately combining the coil arrangement, magnetic field strength and frequency.0 Spinning that can be used in dielectric heating method The material of the cap is generally a substance that causes dielectric loss, and may include ceramics having polar groups, depending on the frequency of the applied electric field and the properties of the polymer to be molded.

When heating a dielectric spinneret using a dielectric heating method, an electrode is usually placed parallel or perpendicular to the surface of the spinneret, and an alternating electric field parallel or perpendicular to the surface of the spinneret is applied. n1 collar electric body loss occurs and heat is generated.

The capillary used in the thermal fluid heating process is preferably of high thermal conductivity, such as aluminum, stainless steel, iron, copper, brass, silica, nickel.

Inconel, tungsten, tantalum, molybdenum,
Materials such as rhenium, titanium, and niobium are used. The heat medium is selected to match the working temperature and the thin tube, such as water, ammonia, methanol, acetone, Freon 1, etc.
1,7 Leon 2, Freon l 13, O@F*
, n-butane, n-hentane, n-hebutane, benzene, toluene, Downa A, Downa A'B, DC!
20G, D 02091 parachloroethylene, demethyl sulfide.

Monsanto op-s, pyridine, Monsanto cP-3
4. Lithium, sodium, potassium, cesium, mercury, lead, indium, tin, etc. are used in the form of fluids or gases.

The width of the slit in the messier-like knot cap depends on its material and the heat transfer efficiency between the polymers, but it is preferably So#~3.
, preferably in the range of lOOμ to l■. If the gap is too narrow, it will be difficult for a viscous polymer to pass through the gap, and if the gap is too wide, it will cause insufficient heating of the polymer and uneven heating, which is undesirable.

The polymer needs to pass through the slits of the Mexier-like spinneret within a period of time without losing the ability to form a molded article. If the time for passing through the slits is too long, the ability to form a molded article will be lost, and if the time is too short, the polymer cannot be heated to an appropriate temperature, so there is an optimum range of passing time. This range depends on the type of polymer, the temperature and thickness of the messier-like spinneret, the size of the #l gap, and the discharge rate.

Next, a method of supplying the aromatic polyamide powder to the messier-like spinneret and melt spinning in the present invention will be explained.

Aromatic polyamides are usually produced by interfacial polymerization in a system of detrahydrocarbon/water or methyl ethyl ketone/water, or as a solution in a polar aprotic solvent such as dimethylformamide, dimethylacetamide, M-methyl-pyrrolidone, etc. It is prepared by polymerization method etc. The polymer is generally dissolved or present in fine powder form in these polymerization solvents.

The preferred method for separating the polymer from the polymerization solvent is usually to extract and remove the solvent by washing, and the solvent contained in the washing solution is generally separated by distillation, freeze separation, or a combination of these and extraction. the size of the polymer powder;
If the shape is prepared by interfacial polymerization, the temperature at that time.

Shear rate 1 is influenced by the coagulation rate of the polymer, etc., and when it is prepared by a solution polymerization method, the temperature at which the extraction washing liquid is added to the polymer solution subjected to l14Ili by the solution polymerization method,
Shear rate, 11 [affected by solidification rate of coalescence, etc. Easy-to-handle polymer powder average 11μ~1000JI
It is.

In the present invention, the powder of the polymer may be used, or it may be compressed into a suitable shape such as a #i rond shape.

As a device for feeding the solid polymer to the mesh-like spinneret, a screw or a plunger can be used in the case of powder, and a plunger can be used in the case of rond. It is preferable to supply the skeleton solid polymer by pressing it against the scissor tip with a pressure of ~sob/at. In addition to efficient heat transfer through K, melting occurs under pressure, resulting in a certain pressurized defoaming effect. Defoaming is required in order to continuously discharge the melt from the discharge port. However, the length of the zone required for this defoaming may be very long. When producing fibers as shown in Example IK below, the length of the zone required 61 p for degassing at a pressure of SO-/-1 was approximately □. Device J for supplying this solid polymer onto a flat body
It is preferable to replace the atmosphere inside with an inert gas such as nitrogen gas.

The aromatic boriaod polymer used in the present invention melts, albeit temporarily.

The melting point can be measured by thermally analyzing the polymer using a means such as differential thermal analysis (DT), differential calorimetry (D80), or blow tester. The melting point and decomposition start point of the polymer are close to each other, and in DT mode in air and D80K, the two are usually observed to overlap, so the melting point can be clearly determined. To do this, make a measurement in an inert gas,
I wonder if the starting point of decomposition should be moved to a higher temperature and then measured.

For example, thermal analysis of polymetaphenylene iso7-talad in nitrogen at a heating rate of 10°C/min shows approximately 4
A melting point of 00°C K11ll is observed. On the other hand, when examining the same polymer under the same conditions using τG (thermogravimetric analysis) k, approximately 4
At 30°C, the weight loss start point (which is the same as the decomposition start point) is observed. Although such polymers melt temporarily, their melting point and decomposition start point are close to each other, so they must be immediately melt-molded, which is impossible with conventional methods.

In other words, when the decomposition initiation point is heated to a high temperature, scission of the main chain of the polymer progresses, and at the same time, a complex reaction that usually involves crosslinking between the main chains occurs, but these reactions are This also tends to cause the ability to form molded products to be lost, and the smaller the amount that progresses to the molding stage, the more preferable it is.

The ability to form a molded product as used in the present invention refers to performance when all of the following requirements (1) to (3) are satisfied.

(1) It should be possible to discharge from the discharge port referred to in the present invention. (The viscosity of the polymer can be reduced to the viscosity necessary for passing through the discharge port.) For this purpose, an appropriate degree of polymerization range is required. For example, in the case of polymetaphenylene iso7-talad , OX, V, in ifMP defined later is as~1oo
4 hours is preferable.

(2) The #polymer should be able to be continuously discharged from the discharge port side by side in the discharge direction.

(3) Mechanical stiffness after cooling the discharged continuous body of the nine-layered structure is within the practical range.

The range of specific physical property values for the above requirements (1) to (3) is (1) The viscosity K is 100,000 poise or less.

The mechanical strength of (3) is preferably αsr/mu or more.

Generally, it is considered that the following qualitative formula holds true regarding the time for which the polymer is maintained in the molten state 11 and the amount of modification at which the ability to form a molded article is lost.

t: Time to maintain the polymer in a molten state at 1IIK q: Amount of heat required for melting λ: Thermal conductivity T: Heating degree ldT/lxl: Heating temperature gradient position (1: Activation that causes loss of ability to form molded articles) Energy m:
The amount of transformation R at which the ability to form a molded product is lost is considered to be the gas constant, that is, the amount of time required for the material to pass through the mesh spinneret within this time.

For example, the polymer is polymetaphenylene isophthalamide, the mesh spinneret is a plain weave of 30 meshes,
When the molten polymer temperature (1) is about 420°C, the molten state retention time (1) is 15 to 200 seconds, preferably 1 to 50 seconds.
Second osis-ca is exposed.

In the present invention, the aromatic boria ζ-dopolymer extruded from the mesh-like spinneret is cooled and solidified by cooling gas or cooling liquid immediately after spinning, and taken off at the same time as solidification.

The extremely thick aromatic polyamide fibers and their aggregates melt-spun by K as described above are subjected to arc elongation, heat treatment, etc.
The oriented crystallization of the fibers is increased. For stretching and heat treatment, known methods for the aromatic polyand fiber are applied. For example, the fibers are stretched in a high-temperature wet state such as hot water, boiling water, or high-temperature steam to advance the orientation of the fibers, and then the glass transition point of the fibers (depending on the polymer, ZSO℃~28g1
A method of dry heat stretching and heat treatment at 0.11 °C or above to promote orientation and crystallization of the fibers; or a method of dry heat stretching and heat treatment without stretching in a wet state is applied. When drawing and heat treating the fibers using dry heat, it is preferable to carry out the stretching and heat treatment after removing most of the water contained in the fibers by pre-drying.

An advantage of the present invention is that it has been able to provide a novel ultra-thick aromatic polyamide fiber and an aggregate thereof that have not been available until now.

That is, the novel ultra-thick aromatic polyamide fiber aggregate of the present invention has a certain range of variation in its cross-sectional shape, size, distribution, and fiber cross-section along the fiber-axis direction. The fibers could not be obtained from conventionally known fiber manufacturing methods, and the aggregate had structural properties as well, and various interesting properties that could not be obtained from conventionally known fibers were expressed. Ru.

The cross-sectional shape, size, distribution, and range of variation in the fiber cross-section in the fiber axis direction are partially similar to natural bristles, so the ultra-thick aromatic polyamide fiber of the present invention It can be said that it is possible to provide heat-resistant, extremely thick fibers with properties similar to such natural products.

Thus, the novel ultra-thick aromatic polyamide fiber and fiber complex aggregate of the present invention can be used in brush materials, brush materials, concrete reinforcement materials, heat-resistant net belts, and other conventional aromatic polyamide fibers. It can be used as a material for ultra-thick fiber products, especially in fields where heat resistance is required.

O iron fiber aggregates of the present invention often develop a high degree of crimp through heat treatment due to moderate irregularities in fiber cross section and length direction and anisotropic cooling effect provided during fiber forming. This property can be applied to increase the intertwining of fibers.

The fiber aggregate of the present invention further comprises the parallel array sheet,
In addition, it can also be applied to products such as orthogonal nonwoven fabrics made by orthogonally bonding them together, and random structured nonwoven fabrics made by applying electricity or air to randomize leather.

Another significant effect of the present invention is that it has been able to provide a method for producing ultra-thick aromatic polyamide fibers and aggregates thereof having the various useful characteristics as described above by melt spinning. There are many things that can be mentioned.

That is, the present invention has made it possible to produce extremely thick aromatic polyamide fibers by a highly productive melt spinning method that does not require complicated steps such as solvent treatment.

Additionally, conventional solvents must be extracted dry.

In wet and semi-wet spinning methods, solvent extraction is insufficient especially in the case of very thick fibers, resulting in unsatisfactory mechanical properties.

In contrast, the present invention provides ultra-thick aromatic polyamide fibers and aggregates thereof that have practically sufficient mechanical properties, heat resistance, and other properties.

Hereinafter, the present invention will be explained by way of specific examples.
These do not limit the invention in any way.

In addition, the intrinsic viscosity (D, V) in the examples is expressed by the following formula.

Engineering, V, -Lnlr@L:/ (L5 (however, ηre
L is the value obtained by dividing the viscosity of the αsf/xood solution of the polymer in a capillary viscometer by the viscosity of the solvent determined using the same viscosity needle. ) In the examples, "parts" means "parts by weight."

Example! Polymetaphenylene isophthalamide (N-methylpyrrolidone (IM
The average particle length of Z, V, measured in F) is L2 is 5osrn.

The dried polymer powder was transferred to an extruder with a plunger set directly in front of it (1110 m inside the barrel, 100 s length).
The molding area attached to the bottom of this extruder is pressed with Il [ll! Seal the part that does not discharge like 8III+ with aluminum inorganic adhesive and wire mesh (stainless steel 11111 & 34101 * 8 @ I
: 'Sheet plain weave, porosity 77) and coated wire mesh with #
Gourd I W/aiO current is applied, and the pattern-shaped combined powder is approximately 420
℃, melted and flowed between the meshes (slits) of the plated wire mesh, and cooled at the same time by blowing cooling air at a speed of about α5/sec toward the discharge side of the wire mesh to form a fibrous material. #IB style and nashia
A very thick polymetaphenylene isophthalamide fiber aggregate consisting of fibers having an average fineness of 400 deniers and a cross section of about 180 μm on a side and a substantially square shape was obtained by pulling the fibers at 5IIZ.

The temperature of the nine barrels used was 340°C, the pressure of the plunger was 5oll+/-, and the melting point of the combined pattern was 400°C, and the polymer was not melted in the barrel.

The average strength and elongation of the bundle obtained from this fiber aggregate,
The initial Young's modulus is L t f/da, respectively.

35'lk, SS f/de. t
CVCF) are all.

ov(A) was a2s, and the average value of n/a was L4.

Next, this fiber bundle was stretched on a hot plate at 290°C to approximately λO times. 7G rates are zaf/de, ts%, and y, respectively.

There is f/de"t", and cv(r) is ago, ov
(A) The average value of α2S, D/(l was L4.

Example 2 What is the average particle size of polymetaphenylene in 7-talamide, which was polymerized in the same manner as in Example 1 and has a 7 mm, v, of a7 as measured by IMF? Dry polymer powder of 0srtr was loaded into a 33-CK heated 1-knee press machine (within the barrel of 2%, length ""), which was installed directly at the center of the screw. A small piece) is transferred to the bottom of the extruder with a photo-etched perforated thin plate (made of stainless steel).

The thickness is a31111 + The shape of the hole is similar to that in Fig. 2, the porosity is SO-, and the area of the hole is
3ai, the molding area had a diameter II,K. )k, a current of about tow/cd is passed through the nozzle, the polymer powder is melted at about 40°C, and the molten fluid is discharged through the holes (slits) of the nozzle, and at the same time about a A moderate amount of cooling air was blown for 5117 seconds towards the discharge side surface of the nozzle to form a filamentous stream, LO11! /min, average fineness is 390
An ultra-thick polyester 7-ethylene iso-7 talamide fiber aggregate having a denier and a new area of about 2 x 10-'- was obtained. The average strength, elongation, and initial Young's modulus of the bundle obtained from this fiber aggregate are each L 3 f/da.

sod, 4sf/de. Also, cvCr) is aQ
ay(A) is (Ll 6 , D, the average value of 'a is L3
Met.

Example 3 The average particle diameter of polymethaxylylene iso-7-talamide obtained by polymerizing meta-xylylene diamine and ino-7-talyl chloride at the tetrahydrofuran/water interface (measured in CIMF, 9 IJ, α7) 200 prn of dried polymer powder t1 Pressed with a Granger set extruder similar to Example 1, and then attached to the bottom of a heavy machine. Wire mesh (stainless steel, lI) sealed with adhesive
Diameter α” l jllml + 60 meters.

A current of about 4 W/- is applied to the wire mesh to melt the polymer powder, and the gap between the eyes (slits) of the plated wire mesh is
At the same time, cooling air at a speed of about L (11 I/sec) is blown toward the discharge side surface of the wire gauze, forming a fibrous stream at ZS*/min, and the average line f (Da) is 11. 0
An extremely thick polymethaxylylene inophthalate fiber aggregate of denier and having an average side of about 9 s μm was obtained. The average strength of the bundle obtained from this fiber aggregate.

elongation [, the initial Young's modulus is a s t / da
I7 G-, 30 f/da. Also ovJ5
．． avQJ.

The average value of D/(L is aljl, (119°L), respectively.
It was m.

The temperature of the barrel was 25 G'C, the pressure of the plunger was 60 -/-, and the melting point of the polymer was 380 °C.
The polymer is not melted within the cyparel.

Example 4 Metaphenylene siatone 42. Part s, 411 parts of isophthalic acid chloride, 1 part of meta-aminobenzoic acid chloride hydrochloride
5 parts were polymerized at the detrahydro 7 run/water interface (
A dried copolymer powder of meta-phenylene diamine, isophthalic acid chloride and meta-aminobenzoic acid chloride with an average particle size of 1 OGIIIm (having a mean particle size of α9 of 0.05 mm as measured on a mMp piece) was prepared in the same manner as in Example 2. 32<1℃
It has a pattern similar to that shown in FIG. 2, which is transferred by a screw type extruder heated to
The material is cast iron, the thickness is 3 cm, the porosity is 47 cm, and the
Feed the gold with a minimum area of λl- as seen from the discharge surface of the two holes, and the die K 2151HM, 15
An alternating magnetic field of W/- is applied to generate an eddy current on the surface of the nozzle to generate heat, melt the polymer powder, cause it to melt and flow into the slits of the nozzle, and discharge it, while simultaneously cooling at a rate of about ZOW/sec. Blowing wind toward the discharge side surface of the mouthpiece,
α5m! / min. average fineness (5e) is 4200
A fiber aggregate of extremely thick denier fibers was obtained. The average strength, elongation, and initial Young's modulus of the bundle obtained from this fiber assembly were alsf/do, ton, and zst/de, respectively. The average values of 9 CV (to), CV (4), and D/(l were α11, 11 m, and Lm, respectively.

Example 5 A polymetaphenylene isophthalamide with a LO of LO as measured in IMP was prepared with an average particle length of 100 #m and transported in a sto'etc heated screw extruder similar to Example 2. Then, a stainless steel via with an inner diameter of +1 Lssl+ and an outer diameter of 81 L Om, which is attached to the bottom of the extruder, is fed to a meshier-like mouthpiece made of flat IIK woven fabric with a porosity of 6s.
A tin liquid heated to KSOO°C is flowed into the scissor cap to generate heat, and the polymer powder is melted and discharged into the slits of the scissor cap to form f11 melt flow, and at the same time cooling air at a rate of KL71 L/sec is applied. Spray it on the discharge side surface of the scissors nozzle, and
The fibers were drawn at SS/min to obtain an aggregate having an average fineness of 5 so denier OX thick O fibers.

The average strength of this fiber bundle I1. The elongation* and initial Young's modulus are (L?f/h, 181G, 321/rla, eV(F), cvcA), and the average value of D/+10 is α11. α12. It was Lm.

Reference Example 1 Measured in IMF 91. Polymetaphenylene isophthalamide having a V of 10 was dissolved in IMF at 20% by weight, extruded through a nozzle with a hole diameter of a S and a number of holes of 100, coagulated in a calcium chloride bath at SS°C, washed with water, and made into a fixed length. Dry. However, the cutting speed is L OIt /min, and the draft ratio is (L5).The average fineness of the obtained nine fibers is 9. The strength, elongation, and Young's modulus are ztoom, αzf/ae, and ts.

It was tlt/h. Moreover, 0V(F)I eV(&) is (LO&aOS), and the cross section of the fiber has a thin skin-core structure, and as mentioned above, it is not a normal ultra-thick fiber with a small size.

[Brief explanation of the drawing]

FIG. 1-IL and FIG. 1-b are examples of meshier-like spinnerets used in the present invention, which are generally called flat wire wire meshes. FIG. 1-a is a plan view thereof, and FIG. 1-b is a newspaper view thereof. FIGS. 2-a and 2-b show another example of the mesh-like ligature cap used in the present invention, which is made by punching holes in a thin metal plate by photo-etching. FIG. 2 is a plan view of company t-a. FIG. 3 is a cross-sectional view of a mesh-like spinneret in which two plain-woven wire meshes are laminated. 1-b, 2-b, and 3 show the portion corresponding to the apparent total volume (Va) occupied under the unit area of the mesh-like portion of the spinneret used in the present invention. FIG. 4 is a cross-sectional view of a mesh spinneret having a general shape used in the present invention.圀、l″′″a 口、tb 日、? -〇'm,z-b day 3

Claims (1)

[Scope of Claims] A very thick aromatic polyamide fiber, which is a fiber made of one kind of aromatic polyamide, characterized in that the average fiber f(DI) thereof is 100 to 10 OOO denier. 2. In the aromatic polyamide fiber, (1) its stitches have irregular periodic changes in the size of the K11li product along its length, and (2) the intrafiber cross-sectional area variation coefficient ['' 0V(F)] is a
2. The ultra-thick aromatic polyamide fiber according to item 1, which is in the range of os to LO. The aromatic polyamide has the following formula (1), (1)
, @-O-R1-0-... (1) H -N-R"-N-...Iso-0-R" -N-... (to) The ultra-thick aromatic polyamide fiber according to claim 1 or 2, which is a polymer consisting essentially of at least one repeating unit selected from the group consisting of: Tun A fiber made of at least one type of aromatic polyamide, the average fineness (De) of which is 100 to too, ooo
An extremely thick aromatic polyamide fiber aggregate characterized by its denier. & In the aromatic polyamide fiber aggregate. <1) Each fiber constituting the aggregate has an irregular periodic change in cross-sectional area in its length direction Kf8, (2) Each fiber has a cross-sectional area within the fiber. Coefficient of variation (aVke)
] is in the range of α05-LO, (3) the ohm product of each fiber when the bundle consisting of a large number of fibers constituting the aggregate is cut in a direction perpendicular to the fiber axis at an arbitrary position The variation of the intra-bundle fiber cross-sectional area coefficient of variation [expressed in aV (9) is in the range of α05NLI,
4. The ultra-thick aromatic polyamide fiber assembly according to item 4. In producing a paper fiber aggregate made of at least one type of aromatic polyamide polymer, a mesh having a large number of closely spaced pores with a porosity expressed by the following formula (% formula %) of about to1 or more is used. Using a spinneret shaped like a mesh, the powder of the aromatic polyamide polymer is supplied to the −0 face opposite to the discharge face of the spinneret, and heat is supplied from a partition member that generates heat from the spinneret shaped like a skeleton mesh. At the same time, the solid powder cone is melted, the melt is extruded through a number of slits surrounded by the partition member, and a cooling fluid is applied to the melt discharge surface of the spinneret and its vicinity. 1 m1 while supplying and cooling
The melt extruded through the llIIt is withdrawn and the molten polymer is heated for 1 hour within a time period such that the molten polymer substantially loses its ability to form carved objects.
A method for producing an extremely thick aromatic polyamide fiber aggregate, which comprises converting the melt into a large number of separated fibrous streamlets and solidifying the melt.