JPH10237717A - Production of dyeable polypropylene fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain dyeable polypropylene fiber having an excellent dyeability, luster as well as highly excellent chroma after dyeing by melt spinning of a certain polypropylene composition without casing fiber breakage during the melt spinning. SOLUTION: This dyeable polypropylene fiber is obtained by melt spinning of a polypropylene composition which in turn is obtained by polymerization, in molten polypropylene, of a monnovinyl monomer such as glycidyl acrylate having glycidyl group in the absence of a crosslinking agent. It is preferable to use a polymerization initiator such as azobisisobutyronitrile in the polymerization.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel process for producing polypropylene fibers. That is, the present invention relates to a method for producing a polypropylene fiber having high productivity and excellent dyeability of the obtained fiber.

[0002]

2. Description of the Related Art There are many reports on techniques for improving the dyeability of polypropylene fibers. One of them is a polymer effective for dyeing polypropylene, for example, nylon,
There is a method of blending a polar polymer such as polyvinyl pyridine and polyglycidyl methacrylate, and some methods have already been put to practical use.

[0003] However, polypropylene has poor compatibility with other polymers, and the blend has a so-called sea / island structure depending on the mixing ratio. For example, when the added amount of the added polar polymer is relatively smaller than that of polypropylene, the polymer generally has an island structure. For this reason, it causes yarn breakage during melt spinning, or causes a decrease in the strength of the obtained fiber.

[0004] The present inventors have already prepared a finely crosslinked polar polymer having an average particle diameter of 0.1 to 0.2 µm as a method for producing polypropylene fibers, and blending this into polypropylene to obtain the above-mentioned islands. It was reported that the structure was refined and the dyeability of polypropylene fiber was improved (Yukio Mizutani, Bull. Chem. Soc. Jpn., 40, 1519 (196
7)).

[0005]

However, in this method, since the crosslinked polar polymer has a small particle size, it is difficult to obtain a uniform dispersion state due to strong cohesiveness.

Further, the present inventors have succeeded in radically polymerizing a vinyl monomer having a glycidyl group and a crosslinking agent in polypropylene in a molten state to uniformly disperse extremely small crosslinked polymer fine particles in polypropylene, We proposed a method for producing dyeable polypropylene fiber which is easy to melt spin. This polypropylene fiber has a very good dyeing property and is a glossy fiber. However, it has been desired to further improve the dyeing property, and particularly to improve the chroma after dyeing.

[0007]

Means for Solving the Problems In view of the above problems, the present inventors have intensively studied. As a result, a monovinyl monomer having a glycidyl group alone or by radical polymerization in polypropylene in a molten state together with another copolymerizable monovinyl monomer,
It has been found that a composition of polypropylene and a vinyl polymer having a glycidyl group can be obtained which is uniform such that no polymerized vinyl polymer particles are observed even by a transmission electron microscope.

As a result, it can be seen that the resulting composition can be melt-spun without any problem, and that the resulting fiber has good dyeability, gloss, and extremely high chroma. The present invention has been completed.

That is, the present invention is characterized in that a polypropylene composition obtained by polymerizing a monovinyl monomer having a glycidyl group in a molten polypropylene in the absence of a crosslinking agent is melt-spun. This is a method for producing polypropylene fibers.

In the present invention, a polypropylene composition to be subjected to melt spinning is obtained by polymerizing a monovinyl monomer having a glycidyl group in a molten polypropylene in the absence of a crosslinking agent.

In general, a vinyl polymer has poor compatibility with polypropylene, and in the present invention, it is considered that a vinyl polymer obtained by polymerization of a monovinyl monomer having a glycidyl group causes a phase separation from a polypropylene phase to form an island structure. Was. However, studies have revealed a completely unexpected fact that in the case of the present invention carried out in the absence of a cross-linking agent, a vinyl polymer having glycidyl groups is present in the polypropylene phase without any island structure. Became. And the polypropylene fiber obtained by melt-spinning the obtained polypropylene composition has further improved dyeing properties and extremely good chroma after dyeing.

In this case, since it is radical polymerization, graft polymerization of a monovinyl monomer having a glycidyl group onto polypropylene is naturally considered. Further, since the diffusion rate of the monomer in the molten polypropylene is considered to be very low, the polymerized vinyl polymer having a glycidyl group is extremely finely dispersed and has an ideal interp.
It is assumed that an enetrating polymer network structure is formed, but details are unknown.

In the present invention, known polypropylenes are used without any particular limitation. For example, a homopolymer of propylene and a copolymer with another monomer copolymerizable with propylene can be exemplified. Specific examples of such other copolymerizable monomers include α-olefins other than propylene, such as ethylene, butene-1, pentene-1, and hexene-1. These other monomers can be used alone or in combination of two or more. The amount of the other monomer used is preferably 30% by weight or less based on propylene. Further, the molecular weight of polypropylene is preferably such that the melt index as an index is in the range of 10 to 50 g / 10 minutes from the viewpoint of melt spinnability of the polypropylene composition.

In the present invention, as the monovinyl monomer having a glycidyl group, a known monovinyl monomer having one or two or more glycidyl groups is used. For example, glycidyl acrylate and glycidyl methacrylate are generally mentioned. These monovinyl monomers having a glycidyl group may be used alone or in combination of two or more.

The monovinyl monomer having a glycidyl group includes acrylic ester, methacrylic ester, styrene, vinyltoluene, maleic anhydride, N
Other monovinyl monomers copolymerizable with a monovinyl monomer having a glycidyl group, such as -phenylmaleimide and N-alkylmaleimide, can also be used in combination. In this case, the amount of the other monovinyl monomer copolymerizable with the glycidyl group-containing monovinyl monomer is 50% by weight based on the glycidyl group-containing monovinyl monomer.
The following is preferred.

In the present invention, the polymerization of the monovinyl monomer having a glycidyl group is not particularly limited as long as it is a method in which a monovinyl monomer having a glycidyl group is supplied to a polypropylene in a molten state and polymerized. In general, a method of providing a supply port of a monovinyl monomer having a glycidyl group at an arbitrary position of an extruder and supplying a monovinyl monomer having a glycidyl group from the supply port to perform polymerization is generally used, but a kneader can also be used. Alternatively, an appropriate amount may be previously blended and then charged into an extruder.

As the polymerization initiator in the above polymerization, any known radical polymerization initiator can be used without any limitation. Specifically, azobisisobutyronitrile, benzoyl peroxide, dicumyl peroxide, Di-t-butyl peroxide and the like can be mentioned. The polymerization initiator may be added in advance to the polypropylene,
It may be added simultaneously with the addition of the monovinyl monomer having a glycidyl group.

The amount of the polymerization initiator used is not particularly limited, but is generally 0.1 to 5 parts by weight, preferably 0.5 to 3 parts by weight, per 100 parts by weight of the monovinyl monomer.

Furthermore, the polymerization time depends on the mixing ratio of the monovinyl monomer having a glycidyl group and the polymerization initiator, and cannot be determined unconditionally.
About 5 minutes is preferable.

The polymerization temperature is 190-250.
C is preferred.

In the present invention, the melt spinning using the polypropylene composition can be carried out in the molten state after the polypropylene composition is produced by the above-mentioned method. 50 ~
After heating at 100 ° C. to polymerize a monovinyl monomer having an unpolymerized glycidyl group which may remain, it is preferable to perform melt spinning. Furthermore, in the drawing at the time of melt spinning or after spinning, in order to prevent yarn breakage, contamination of the working environment, etc., which may occur due to a monovinyl monomer having a glycidyl group slightly remaining in the polypropylene composition, the pellets are subjected to reduced pressure. 70-150 ° C
It is preferable to remove the remaining volatile components by heating at the temperature described above.

It is preferable that a stabilizer is added to the polypropylene composition. As such compounding agents,
Known hindered phenols, system stabilizers, hindered amine system stabilizers, phosphite system stabilizers, sulfur-containing system stabilizers and the like can be suitably used as the polypropylene stabilizer. The stabilizer may be added in advance when producing the polypropylene composition, but is preferably added after producing the polypropylene composition. That is, it is preferable that the pellets of the polypropylene composition obtained after the polymerization are re-granulated using a vent together with a stabilizer. In general, the amount of the stabilizer is preferably about 0.1 to 2.0% by weight based on the total amount of the stabilizer and polypropylene.

As the melt spinning method, a known method is employed without any particular limitation. In addition, the polypropylene fiber obtained by melt spinning is drawn as needed. The drawing is suitably performed at a linear magnification of 5 to 10 times, and when the film is drawn at such a drawing ratio, in the present invention, a fiber having good tensile strength can be obtained without any trouble such as fiber breakage.

The polypropylene fiber obtained by the method of the present invention can be dyed by a known method. Usually, a method of dyeing with a disperse dye by a high temperature dyeing method or a carrier dyeing method is generally used. At this time, when the dye molecule has a group capable of reacting with an epoxy group such as an amino group or a phenolic hydroxyl group, the dye molecule is completely fixed in the fiber, so that it does not fade even by acetone extraction and has a sufficient washing fastness. Is preferred.

Prior to dyeing, ethylenediamine,
When pretreatment is performed with a compound having an amino group such as ethanolamine or triethanolamine, the obtained fiber can be dyed with an acid dye.

[0026]

As will be understood from the above description, according to the method of the present invention, the dyeing property is good, glossy, and
It is possible to obtain a polypropylene fiber having extremely good chroma after dyeing with high productivity without occurrence of yarn breakage during melt spinning.

[0027]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto.

The physical properties of the polypropylene fibers shown in the examples and comparative examples and the chroma indicating the vividness of the dyed color are values measured by the following methods.

Denier (g / 9000 m); length 90
Weight of fiber per 00m. -Elongation (%): Using a tensile tester Autograph 200 manufactured by Shimadzu Corporation, sample length 100 mm, tensile speed 300
% / Min. -Breaking strength (g / d): Using an Autograph 200 manufactured by Shimadzu Corporation, sample length 100 mm, tensile speed 300%
/ Min. -Young's modulus (g / d); using an Autograph 200 manufactured by Shimadzu Corporation, sample length 100 mm, tensile speed 300%
/ Min. -Saturation: 1 g of fiber is placed in a glass cylindrical sample case with a diameter of 4 cm and a height of 0.5 cm, and Suga Test Machine Co., Ltd.
The color was measured by H, C, L display using SM Color Computer Model 3 manufactured by KK.

Example 1 To 100% by weight of glycidyl methacrylate, 3 parts by weight of di-t-butyl peroxide was added. The monomer mixture was sufficiently mixed in advance in a proportion of 5.15 parts by weight with respect to 100 parts by weight of polypropylene powder (melt index: 16 g / 10 minutes, no stabilizer), and then 190 parts by weight in a twin-screw extruder. The mixture was heated and melted at a temperature of about 240 ° C., polymerized, and then pelletized. The pellets were left to stand overnight at 70 ° C in N2 and cured.
0.5% by weight of 2,6-di-tert-butyl-
4-Methylphenol was added as a stabilizer and re-pelletized at 190 to 230 ° C using the above twin screw extruder.

The obtained pellets are screwed with a screw diameter of 40 m.
0.7 m in diameter attached to an extruder with mφ and L / D = 22
from a nozzle for fiber production having 198 holes of m
Extruded at 300 ° C, put into an air-cooled ring and allowed to cool,
At 200 m / min, an undrawn fiber was obtained. This unstretched fiber was uniaxially stretched at 150 ° C. at a draw ratio of 5 between two pairs of seven-piece goded rolls having different rotation speeds. As a result, it could be carried out without any problems such as thread breakage and nozzle clogging.

The physical properties of the obtained polypropylene fiber were as follows: denier: 1.5 (g / 9000 m), elongation: 21 (%),
Tensile strength: 8.5 (g / d), Young's modulus: 62 (g / d)
d).

[0033] The obtained polypropylene fiber was
on Polyester REDBL-E, Kaya
lon Polyester EBL-E (all trade names, manufactured by Nippon Kayaku Co., Ltd.), Sumikaron Or
angel SE-B (trade name, Sumitomo Chemical Co., Ltd.)
As a result, Carrier dyeing was performed, and glossy and good dyed yarn was obtained. Further, even if the dyed yarn was washed with acetone, some coloring was observed in acetone, but the state of dyeing hardly changed, and the saturation was 51.5.

Example 2 A monomer mixture 1 comprising 71.4% by weight of glycidyl methacrylate and 28.6% by weight of N-phenylmaleimide
To 00 parts by weight, 2 parts by weight of di-t-butyl peroxide and 2 parts by weight of 1,1-bis (t-butylperoxy) cyclohexane were added. The above monomer mixture was mixed with a polypropylene powder (melt index 16 g / 1).
(0 min, no stabilizer) Mix well in advance at a ratio of 7 parts by weight to 100 parts by weight, and then heat-melt at 190 to 240 ° C in a twin-screw extruder to perform polymerization. Then, it was granulated into pellets. The pellets, in N _2, 7
After leaving it to stand at 0 ° C. overnight and curing, 2,6-ditert-butyl-4-methylphenol was added as a stabilizer at a ratio of 0.5% by weight, and the mixture was heated to 190 to 2 using the above twin screw extruder.
Repellet at 30 ° C. The obtained pellets were extruded at 230 to 300 ° C. from a fiber production nozzle having 198 holes having a diameter of 0.7 mm and attached to an extruder having a screw diameter of 40 mmφ and L / D = 22, and the pellets were put into an air-cooled ring. After cooling, undrawn fiber was obtained at 200 m / min. This undrawn fiber is drawn at 150 ° C. between two pairs of 7-piece god rolls having different rotation speeds at a draw ratio of 5-6.
The film was uniaxially stretched twice. As a result, it could be carried out without any problems such as thread breakage and nozzle clogging. The obtained polypropylene fiber was used as Kayalon Polyester®.
ED BL-E, Kaylon Polyester
EBL-E (both trade names, manufactured by Nippon Kayaku Co., Ltd.),
Carrier dyeing was performed with Sumikaron Orange SE-B (trade name, manufactured by Sumitomo Chemical Co., Ltd.), and as a result, a glossy and good dyed yarn was obtained. Further, even if the dyed yarn is washed with acetone, some coloring is observed in acetone, but the dyeing condition is hardly changed, and the saturation is 5%.
5.5.

Comparative Example 1 100 parts by weight of a monomer mixture comprising 95% by weight of glycidyl methacrylate and 5% by weight of divinylbenzene were added to
Di-t-butyl peroxide was added at 1.5 parts by weight. The above monomer mixture was mixed with polypropylene powder (melt index 16 g / 10 min, without stabilizer) 1
The mixture was sufficiently mixed in advance at a ratio of 7 parts by weight to 00 parts by weight, then heated and melted at a temperature of 170 to 200 ° C. in a twin-screw extruder, polymerized, and then pelletized. The pellets were left standing at 70 ° C. overnight in N ₂ , cured, and then subjected to melt spinning by adding 0.5% by weight of 2,6-ditert-butyl-4-methylphenol as a stabilizer. Melt spinning uses a spinning machine, 280 ° C
, And stretched 6 times at 130 ° C. As a result, it could be carried out without any problems such as thread breakage and nozzle clogging.

Glycidyl methacrylate-divinylbenzene crosslinked polymer particles having an average particle diameter of 0.05 μm were dispersed in the obtained polypropylene fibers.

The obtained polypropylene fiber was converted to Kayal.
on Polyester REDBL-E, Kaya
lon Polyester EBL-E (all trade names, manufactured by Nippon Kayaku Co., Ltd.), Sumikaron Or
angel SE-B (trade name, Sumitomo Chemical Co., Ltd.)
As a result, Carrier dyeing was performed, and glossy dyed yarn was obtained. Further, even when the dyed yarn was washed with acetone, there was some coloring in acetone, and the chroma was 39.5.

Claims (1)

[Claims] 1. Production of dyeable polypropylene fibers, characterized in that a polypropylene composition obtained by polymerizing a monovinyl monomer having a glycidyl group in a molten polypropylene in the absence of a crosslinking agent is melt-spun. Method.