JP2000034405A - Nylon 6 resin composition and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition excellent in melt spinnability, film- forming properties, and operability by selecting a composition comprising nylon 6 and a specified imide compound and having a specified water content and a specified ε-caprolactam level as determined in a molten state. SOLUTION: This composition comprises nylon 6 and imide compounds of formulas I and/or II and has a water content of 0.02 wt.% or below and an ε-caprolactam level of at most 0.25 mol per kg of the composition as measured after being molten at 250 deg.C for 5 hr at 0.01 Torr or below. In the formulae, R is H, a 1-8C alkyl, an aryl, or a cycloalkyl, with the proviso that the aryl may be substituted with 1-4C alkyls or halogens or may be hydrogenated on at least a part of the ring; X is a 1-8C alkylene, -CR'=CH- (wherein R' is H, a 1-4C alkyl, or a halogen), or a group of formula III or IV (wherein the arylene may be substituted with 1-4C alkyls or halogens); and Y is a group of any one of the formulae V to VII.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nylon 6 resin composition having improved melt spinnability, film forming property and operability, and a method for producing the same.

[0002]

2. Description of the Related Art Nylon 6 resin is a versatile engineering plastic excellent in mechanical strength, heat resistance, chemical resistance, workability, etc., and is used in automobiles and home appliances, including tire cords, clothing and packaging films. Widely used as parts of office equipment.

[0003] Generally, a chip of nylon 6 resin produced by melt polymerization or melt polycondensation contains a considerable amount of unreacted ε-caprolactam and oligomers. Have been. However, even if the removal by hot water extraction is performed, for example, when melt spun into fibers, if the melt extrusion is performed for a long time, these ε-caprolactam and oligomers are regenerated, and the discharge hole of the die is discharged. It accumulates in the periphery and eventually undergoes thermal denaturation around the ejection holes. As a result, the yarn is deformed in the vicinity of the discharge hole, and yarn breakage or yarn unevenness occurs. Also, when producing a film, since ε-caprolactam and oligomers are regenerated when the chips are melted, there has been a problem that the film may be cut or the quality may be deteriorated.

In order to solve these problems, various methods have heretofore been tried. However, a general method is to mix an inorganic compound with nylon 6 resin. 6 compositions (Japanese Patent Publication No. 55-20007) and nylon 6 compositions containing a specific amount of magnesium oxide fine particles having a specific crystal structure (Japanese Patent Publication No. 55-27172) have been proposed. However, these inorganic compounds are solid powders at the melting temperature of nylon 6, and if spinning is performed for a long time, the nozzle pressure will increase, causing a problem in operation. In addition, adding a large amount of ε-caprolactam or oligomer for the purpose of further reducing ε-caprolactam or oligomer also has a problem in that the quality of products such as spinning stability and yarn unevenness is deteriorated.

[0005] On the other hand, as a method of reducing the amount of regenerated ε-caprolactam or oligomer during melt molding, various methods of blocking the terminal of the nylon 6 molecular chain have been tried, for example, by using a specific amount of monoamino hydrocarbon. Method of blocking the terminal of a carboxyl group (JP-A-62-252424)
Further, a method of blocking the terminal of a carboxyl group with cyclohexylamine or the like (JP-A-8-231711) has been proposed. However, these methods can reduce the re-generation of ε-caprolactam and oligomers during the melt molding of nylon 6, but it is difficult to obtain those having a high degree of polymerization. There is a problem that physical properties are deteriorated.

[0006]

DISCLOSURE OF THE INVENTION The present invention provides a method for producing ε-caprolactam which is low in melt spinning and film formation.
An object of the present invention is to provide a nylon 6 resin composition having good quality and improved melt spinnability, film forming property and operability, and a method for producing the same.

[0007]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have found that this object can be achieved by blending a specific imide compound into nylon 6 resin. Heading, the present invention has been reached.

More specifically, the gist of the present invention is as follows: (1) A composition comprising nylon 6 and an imide compound represented by the following formula and / or wherein the water content is 0.02% by weight. Up to 0.01 Torr, 250 ° C
A nylon 6 resin composition, wherein the amount of ε-caprolactam detected when melted for a time is 0.25 mol or less per 1 kg of the resin composition.

Embedded image (2) The ratio (A) / (B) of the molar number (A) of the terminal amino group of nylon 6 to the molar number (B) of the imide group of the imide compound is 0.1 to
2. The method for producing a nylon 6 resin composition according to the above (1), wherein the composition is blended so as to be 2 and melt-blended.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The nylon 6 resin in the present invention is obtained by polymerization of ε-caprolactam or polycondensation of 6-aminocaproic acid, and is a melt-moldable polymer having a caproamide unit as a main component.

The relative viscosity of the above nylon 6 resin is preferably in the range of 1.5 to 5.0 as a value obtained by using 97% by weight concentrated sulfuric acid as a solvent at a temperature of 25 ° C. and a concentration of 1 g / dl. If the relative viscosity is less than 1.5, the mechanical strength of the fiber or film decreases. Conversely this is 5.0
If the ratio exceeds 1, the moldability rapidly decreases.

The nylon 6 resin contains various lactams other than ε-caprolactam and 6-aminocaproic acid, an aminocarboxylic acid or a nylon salt in an amount of 20 mol% as a copolymer component, as long as the properties of the present invention are not impaired. Less than,
Preferably, it may be contained at a ratio of 10 mol% or less.

Specific examples of the above-mentioned copolymer component include ω-
Laurolactam, 11-aminoundecanoic acid, 12-aminododecanoic acid, p-aminomethylbenzoic acid, nylon 46
Salt, Nylon 66 salt, Nylon 610 salt, Nylon 6T salt, Nylon 9T salt, and salts of metaxylylenediamine with adipic acid.

As the imide compound used in the present invention, a resin composition having a water content of 0.02% by weight or less
rr or less, ε- detected when melted at 250 ° C for 5 hours
Caprolactam amount is 0.25mol per 1kg of resin composition
You need to choose:

The imide compound represented by the above formula includes succinimide, N-methylsuccinimide, N-
Ethyl succinimide, N-phenylsuccinimide,
Glutarimide, maleimide, N-methylmaleimide,
N-ethylmaleimide, N-phenylmaleimide, 3-
Methylmaleimide, 3-ethylmaleimide, 3-chloromaleimide, 3-methyl-N-phenylmaleimide, phthalimide, N-methylphthalimide, N-ethylphthalimide, N-phenylmaleimide, 1,8-naphthalenedicarboximide, N- Methyl-1,8-naphthalenedicarboximide, N-ethyl-1,8-naphthalenedicarboximide, N-phenyl-1,8-naphthalenedicarboximide, 1,2-cyclohexanedicarboximide, N-
Methyl-1,2-cyclohexanedicarboximide, N-
Ethyl-1,2-cyclohexanedicarboximide and the like.

Further, specific examples of the imide compound represented by the above formula include 1,2,4,5-benzenetetracarboximide, 3,4,4 ', 5'-biphenyltetracarboximide, 1,2,4
3,4-cyclobutanetetracarboximide and the like.

Next, a method for producing the polyamide 6 resin composition of the present invention will be described. In order to produce the nylon 6 resin composition of the present invention, the number of moles of the terminal amino group of nylon 6 is determined.
Ratio of (A) and the number of moles of imide group of imide compound (B)
It is necessary to blend and melt blend (A) / (B) to be 0.1-2, and to blend and melt blend (A) / (B) to be 0.3-1. preferable.

At this time, the nylon 6 resin and the imide compound can be employed by any melt-kneading method as long as they are uniformly mixed with each other. It is preferable to mix in the above proportions, mix (dry blend) with a tumbler blender, Henschel mixer, ribbon mixer or the like, and melt-knead using a kneader such as an extruder (extruder) or a kneader. The temperature during melt kneading is not particularly limited as long as it is a temperature at which the polyamide 6 resin is melted, but is usually used in the range of 200 to 270 ° C.

The resin composition of the present invention contains a heat stabilizer, a weathering agent, an inorganic filler, a reinforcing agent, and the like, as long as the physical properties are not impaired.
Antioxidants, impact modifiers, plasticizers, pigments, lubricants, flame retardants and the like may be added, and these are added during polymerization or during melt kneading or melt molding.

Further, the resin composition of the present invention comprises nylon 6
It can also be used by mixing with other thermoplastic resins. Specific examples of such a thermoplastic resin include polybutadiene, butadiene / styrene copolymer, acrylic rubber, ethylene / propylene copolymer, ethylene / propylene /
Butadiene copolymer, natural rubber, chlorinated butyl rubber, chlorinated polyethylene and other elastomers or their acid-modified products such as maleic anhydride, styrene / maleic anhydride copolymer, styrene / phenylmaleimide copolymer,
Polyethylene, polypropylene, butadiene / acrylonitrile copolymer, polyvinyl chloride, polyethylene terephthalate, polybutylene terephthalate, polyacetal, polyvinylidene fluoride, polysulfone, polyphenylene sulfide, polyether sulfone, phenoxy resin, polyphenylene ether, polymethyl methacrylate, polyether ketone , Polycarbonate, polytetrafluoroethylene, polyarylate and the like.

Further, the resin composition of the present invention can be made into a fiber, a film or a molded product by a conventional method.

[0021]

When the nylon 6 resin composition of the present invention melts,
The reason for suppressing the regeneration of caprolactam is that the imide compound undergoes an exchange reaction with the amino terminal of nylon 6, thereby blocking the amino terminal and suppressing the production rate of ε-caprolactam by cyclization from the amino terminal. It is estimated that it is possible. Therefore, during melt spinning or film formation,
Stable operation is possible without causing thread breakage, yarn unevenness, film breakage, and the like.

[0022]

Next, the present invention will be described more specifically with reference to examples. The raw materials and measuring methods used in the examples and comparative examples are as follows. 1. Raw materials ・ Nylon 6 polymer Unitika, A1030BRL, relative viscosity 2.5, terminal amino group concentration 55 mol / ton ・ Succinimide Ishizu Pharmaceutical, reagent product ・ Phthalimide Ishizu Pharmaceutical, reagent product ・ 1,2,4,5- Benzenetetracarboximide Aldrich, reagent product

2. Measurement method (a) Terminal amino group concentration 0.5 g of nylon 6 polymer chip and m-cresol 20
was dissolved in the flask at 60 ° C., cooled to room temperature, and titrated with a 0.1 N p-toluenesulfonic acid aqueous solution. (b) Detected amount of ε-caprolactam (cyclic monomer) A resin composition having a water content of 0.02% by weight or less was reduced to 0.01 Torr or less,
After melting at 250 ° C. for 5 hours, the measurement was performed on the pulverized product obtained by freeze-pulverization. For the detection amount of ε-caprolactam, the crushed product was extracted with hot water at 100 ° C., and then ε-caprolactam in the extracted water was quantified using a high performance liquid chromatograph (600E, manufactured by Waters). In addition,
The high performance liquid chromatograph measurement was performed under the following conditions. Column: C ₁₈ (Waters Company, length 250 mm, inner diameter 4.6 mm) Column temperature: room temperature Eluent: methanol / water (35/65, volume ratio) Flow rate: 0.7 ml / min, Detector: UV 210 nm

Example 1 To 100 parts by weight of a nylon 6 polymer chip, 0.56 parts by weight of succinimide was blended, dry-blended by a tumbler blender, and then melt-kneaded by an extruder to make polyamide 6 and succinimide uniform. To obtain a chip of the resin composition mixed. At this time, the ratio (A) / (B) of the number of moles (A) of the terminal amino group of the nylon 6 homopolymer to the number of moles (B) of the succinimide was blended at a ratio of 1, and the temperature in the extruder was 205 ℃ ~ 255 ℃ ~ 2
The temperature was adjusted to three stages at 65 ° C, and the residence time was 3 minutes. Next, a part of the chip was dried under reduced pressure at 100 ° C. for 12 hours to reduce the water content to 0.02% by weight or less,
Melted at 250 ° C. for 5 hours or less at Torr. After the resin composition after melting was freeze-pulverized in liquid nitrogen, the amount of ε-caprolactam detected in the pulverized material was determined by high performance liquid chromatography.

Example 2 Instead of 0.56 parts by weight of succinimide, phthalimide was used instead of 0.56 parts by weight.
A pulverized product of the resin composition was obtained in the same manner as in Example 1 except that 83 parts by weight was used, and the amount of ε-caprolactam detected in the pulverized product was determined.

Example 3 A pulverized resin composition was obtained in the same manner as in Example 1, except that 0.58 parts by weight of 1,2,4,5-benzenetetracarboximide was used instead of 0.56 parts by weight of succinimide. The amount of ε-caprolactam detected in the ground product was determined.

Comparative Example 1 A nylon 6 homopolymer chip was dried under reduced pressure at 100 ° C. for 12 hours to a water content of not more than 0.02% by weight, and was dried in a glass tube.
Melted at 250 ° C. for 5 hours at 0.01 Torr or less. After the melted nylon 6 homopolymer was freeze-pulverized in liquid nitrogen, the amount of ε-caprolactam detected in the pulverized product was determined.

The results in Examples 1 to 3 and Comparative Example 1 are shown in Table 1. The detected amount of ε-caprolactam shown in Table 1 is the amount (mol number) of ε-caprolactam detected with respect to 1 kg of the nylon 6 resin composition.

[0029]

[Table 1]

Example 4 Nylon 6 polymer chips were mixed with the number of moles (A) of the terminal amino group of the nylon 6 polymer and the number of moles of succinimide.
Succinimide was blended so that the ratio (A) / (B) with (B) became 1, and this was supplied to an extruder and melt-spun at 260 ° C. At this time, a 24-hole, Y-shaped discharge hole was used as a die, extruded at a discharge rate of 29 g / min, and wound at a speed of 4000 m / min to obtain a 65 denier, 24-filament yarn. Every time a yarn break occurred, spinning was performed for a total of one week while removing the heat denatured material around the hole of the die, and the number of yarn breaks during this time was examined.

Example 5 Except that phthalimide was used instead of succinimide,
Spinning was performed for a total of one week in the same manner as in Example 4, and the number of yarn breaks during this time was examined.

Example 6 A total of 1 was obtained in the same manner as in Example 4 except that 1,2,4,5-benzenetetracarboximide was used instead of succinimide.
Weekly spinning was performed, and the number of yarn breaks during this period was examined.

Comparative Example 2 Spinning was performed for a total of one week in the same manner as in Example 4 except that no succinimide was added, and the number of yarn breaks during this time was examined.

Table 2 shows the results of Examples 4 to 6 and Comparative Example 2.

[0035]

[Table 2]

[0036]

According to the present invention, there is provided a nylon 6 resin composition capable of producing a high quality fiber or film with a small amount of ε-caprolactam during melt spinning or film formation, and a method for producing the same. Can be provided.

Claims (2)

[Claims] 1. A resin composition comprising nylon 6 and an imide compound represented by the following formula and / or wherein the water content of the resin composition is adjusted to 0.02% by weight or less to 0.01 Torr or less at 250 ° C. A nylon 6 resin composition, wherein the amount of ε-caprolactam detected when melted for a time is 0.25 mol or less per 1 kg of the resin composition. Embedded image 2. The number of moles (A) of the terminal amino group of nylon 6.
And the molar number of the imide group of the imide compound (B) (A) /
2. The method for producing a nylon 6 resin composition according to claim 1, wherein (B) is blended so as to be 0.1 to 2 and melt-blended.