JP2000095861A - Nylon 6 resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition producing a small amount of ε- caprolactam at the time of melt spinning, forming a film, etc., good in quality, improved in melt spinning and film-forming properties and operating efficiency and useful for tire cords, etc., by compounding a specific bislactam-based compound with nylon 6 (or its copolymer). SOLUTION: This composition comprises (A) nylon 6 (or its copolymer) and (B) a bislactam-based compound represented by the formula (R1 and R2 are each a 2-10C alkylene; X is a 1-8C alkylene, a cycloalkylene or phenylene). The amount of ε-caprolactam detected when regulating the moisture content of the objective composition to <=0.02 wt.% and melting the composition at 250 deg.C under <=0.01 Torr for 30 min is preferably <=0.09 mol based on 1 kg of the resin composition and the ratio (the components C/D) of the number of mol (C) of terminal amino groups in the component A to the number of mol (D) of amide groups in the component B is preferably 0.3-10.

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.

[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 for reducing the amount of regenerated ε-caprolactam and oligomers during melt molding, various methods of blocking the terminal of the nylon 6 molecular chain have been tried, for example, using a specific amount of monoamino hydrocarbon. Method for blocking the terminal of a carboxyl group (Japanese Patent Laid-Open No. 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.

[0007]

Means for Solving the Problems The present inventors have made intensive studies to solve the above problems, and as a result, by blending a specific bislactam compound with nylon 6 (or a copolymer thereof), The inventors have found that this object can be achieved, and have reached the present invention.

That is, the gist of the present invention is as follows: (1) A nylon 6 resin composition comprising nylon 6 (or a copolymer thereof) and a bislactam compound represented by the following formula.

Embedded image (2) The resin composition according to the above (1), wherein the water content of the resin composition is adjusted to 0.02% by weight or less, and the water content is adjusted to 0.01 Torr or less and 250 ° C.
A nylon 6 resin composition characterized in that the amount of ε-caprolactam detected when the resin composition is melted for 30 minutes is 0.09 mol or less per 1 kg of the resin composition. (3) The ratio of the number of moles (A) of the terminal amino group of nylon 6 (or a copolymer thereof) to the number of moles of the amide group (B) of the bislactam compound represented by the above formula (A) / (B) The above (1) or (2), characterized in that it is blended to be 0.3 to 10.
The nylon 6 resin composition as described in the above.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

Nylon 6 (or a copolymer thereof) used in the present invention is obtained by polymerizing ε-caprolactam as a main component or by polycondensation with 6-aminocaproic acid as a main component. Is 80 mol% or more, preferably 90 mol% or more.

The relative viscosity of the above nylon 6 (or its copolymer) is determined by using 97% by weight concentrated sulfuric acid as a solvent at a temperature of 25%.
It is preferably in the range of 1.5 to 5.0 as a value determined under the conditions of ° 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, if it exceeds 5.0, the moldability decreases rapidly.

The copolymer of nylon 6 contains various lactams other than ε-caprolactam and 6-aminocaproic acid, aminocarboxylic acids or nylon salts as copolymer components within a range that does not impair the properties of the present invention. The content is less than 10 mol%, preferably less than 10 mol%.

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 6I salt, nylon 9T salt, salt of meta-xylylenediamine with adipic acid (nylon MXD salt), and the like.

The bislactam compound used in the present invention includes a resin composition having a water content of 0.02% by weight or less.
The amount of ε-caprolactam detected when melted at 250 ° C. for 30 minutes or less at 0.01 Torr or less is 1 kg of the resin composition.
It is necessary to select one that is 0.09 mol or less.

Examples of the bislactam-based compound represented by the above formula include N, N'-terephthaloylbis-ε-caprolactam, N, N'-isophthaloylbis-ε-caprolactam, and N, N'-adipoylbis-ε. -Caprolactam, N, N '
-Terephthaloylbisvalerolactam, N, N'-isophthaloylbisbutyrolactam, N, N'-terephthaloylbisbutyrolactam and the like.

The above compounds can be easily synthesized by reacting a carboxylic acid dihalide with a lactam in the presence of an amine or an inorganic alkali.

In the nylon 6 resin composition of the present invention, the number of moles (A) of the terminal amino group of nylon 6 (or a copolymer thereof) and the number of moles of the amide group of the bislactam compound
The ratio (A) / (B) to (B) is preferably blended so as to be 0.3 to 10, more preferably 0.3 to 2. If the value of (A) / (B) is less than 0.3, the excess bislactam-based compound is decomposed at the time of melt molding, and the resin composition is colored or ε-caprolactam is by-produced. On the other hand, when the value of (A) / (B) exceeds 10, the effect of suppressing the amount of monomer (the amount of ε-caprolactam) generated during melt molding becomes insufficient.

At this time, nylon 6 (or a copolymer thereof)
And the bislactam compound can be employed in any manner as long as they are homogeneously mixed with each other. Specifically, a method of blending (dry blending) a chip of nylon 6 (or a copolymer thereof) with a lactam compound in the above ratio and mixing with a tumbler blender, Henschel mixer, ribbon mixer, or the like, After blending, a method of melting and kneading using a kneader such as an extruder (extruder) or a kneader is used. The temperature at the time of melt-kneading is not particularly limited as long as it is a temperature at which nylon 6 (or a copolymer thereof) is melted, but it is usually used in the range of 200 to 270 ° C.

In the resin composition of the present invention, a heat stabilizer, a weathering agent, an inorganic filler, a reinforcing agent,
Antioxidants, impact modifiers, plasticizers, pigments, lubricants, flame retardants and the like may be added, and these are added during polymerization, dry blending, melt kneading or melt molding.

Further, the resin composition of the present invention comprises nylon 6
(Or a copolymer thereof) can be used in combination with a thermoplastic resin. Specific examples of such a thermoplastic resin include nylon 46, nylon 66, nylon 610, nylon 612, nylon 11, nylon 12, nylon 6T, nylon 6I, nylon 9T, nylon 11T, nylon PACM12,
Elastomers such as nylon MXD6, polybutadiene, butadiene / styrene copolymer, acrylic rubber, ethylene / propylene copolymer, ethylene / propylene / butadiene copolymer, natural rubber, chlorinated butyl rubber, chlorinated polyethylene, and maleic anhydride thereof Acid-modified products, 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 G, polytetrafluoroethylene,
There are 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.

[0022]

The reason why the nylon 6 resin composition of the present invention suppresses the regeneration of ε-caprolactam during melt molding is that the amide group of the lactam compound is exchanged with the terminal amino group of nylon 6 (or a copolymer thereof). It is presumed that the reaction can block the amino terminus and suppress the production rate of ε-caprolactam by cyclization from the amino terminus. Therefore, stable operation can be achieved without causing yarn breakage, yarn unevenness, film breakage, or the like during melt spinning or film formation.

[0023]

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. Ingredients ・ Nylon 6 Unitika, A1030BRL, relative viscosity 2.5, terminal amino group concentration 55 mol / ton ・ N, N'-Adipoylbis-ε-caprolactam [Synthetic product] Adipoyl chloride (reagent, manufactured by Tokyo Chemical Industry Co., Ltd.) It was synthesized by reacting with ε-caprolactam (reagent, manufactured by Tokyo Chemical Industry Co., Ltd.) in diethyl ether for 2 hours in the presence of triethylamine, followed by filtration and drying. N, N'-terephthaloylbis-ε-caprolactam [synthetic product] Terephthaloyl chloride (reagent, manufactured by Tokyo Chemical Industry Co., Ltd.) and ε-caprolactam (reagent, manufactured by Tokyo Chemical Industry Co., Ltd.) in the presence of triethylamine After reacting in chloroform for 2 hours, it was synthesized by filtration and drying.

2. Measurement method (a) Terminal amino group concentration 0.5 g of nylon 6 chip and 20 ml of m-cresol were put in a flask, dissolved at 60 ° C., and then cooled to room temperature.
It was determined by performing a titration with a 1N 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 30 minutes, the measurement was performed on the pulverized material 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, 250mm length, 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 Adipoylbis-ε-caprolactam (0.95 parts by weight) was blended with 100 parts by weight of nylon 6 chips and dry-blended by a tumbler blender. A chip of a resin composition in which -ε-caprolactam was uniformly mixed was obtained. At this time, the ratio (A) / (B) of the number of moles of the terminal amino group of nylon 6 (A) to the number of moles of the amide group of N, N'-adipoylbis-ε-caprolactam (B) is 1 Compounded, the temperature inside the extruder is 205 ℃ ~ 2
It is adjusted to three stages from 55 ° C to 265 ° C, and the residence time is 3
Minutes. Next, a part of the chip was dried under reduced pressure at 100 ° C. for 12 hours to a water content of 0.02% by weight or less, and was melted in a glass tube at 0.01 Torr or less at 250 ° C. for 30 minutes. 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 Same as Example 1 except that 1.00 part by weight of N, N'-terephthaloylbis-.epsilon.-caprolactam was used instead of 0.95 part by weight of N, N'-adipoylbis-.epsilon.-caprolactam. To obtain a crushed product of the resin composition, and the detected amount of ε-caprolactam in the crushed product was determined.

Comparative Example 1 Nylon 6 chips were dried under reduced pressure at 100 ° C. for 12 hours to a water content of 0.02% by weight or less, and were melted in a glass tube at 0.01 Torr or less at 250 ° C. for 30 minutes. Nylon 6 after this melting
Was freeze-ground in liquid nitrogen, and the amount of ε-caprolactam detected in the ground product was determined.

The results of Examples 1 and 2 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 3 A ratio (A) / (B) of the number of moles of the terminal amino group of nylon 6 (A) and the number of moles of N, N'-adipoylbis-ε-caprolactam (B) was applied to a nylon 6 chip. ) Becomes 1 so that N, N'−
Adipoylbis-ε-caprolactam was blended and 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. Each time a thread break occurs, a total of 1
Weekly spinning was performed, and the number of yarn breaks during this period was examined.

Example 4 Spinning for a total of one week in the same manner as in Example 3 except that N, N'-terephthaloylbis-ε-caprolactam was used instead of N, N'-adipoylbis-ε-caprolactam. And the number of yarn breaks during this time was examined.

Comparative Example 2 Spinning was carried out for a total of one week in the same manner as in Example 3 except that N, N'-adipoylbis-ε-caprolactam was not added, and the number of yarn breaks during this time was examined.

Table 2 shows the results of Examples 3 and 4 and Comparative Example 2.

[0035]

[Table 2]

[0036]

According to the present invention, it is possible to obtain a nylon 6 resin composition which has a small amount of ε-caprolactam during melt-spinning, film formation, and the like, and can be used as a high-quality fiber or film.

Claims (3)

[Claims] 1. A nylon 6 resin composition comprising nylon 6 (or a copolymer thereof) and a bislactam-based compound represented by the following formula. Embedded image 2. The resin composition according to claim 1, wherein ε-caprolactam is detected when the resin composition is melted at a water content of 0.02% by weight or less at 250 ° C. for 30 minutes or less at 0.01 Torr or less. A nylon 6 resin composition having an amount of 0.09 mol or less per 1 kg of the resin composition. 3. The ratio of the number of moles (A) of terminal amino groups of nylon 6 (or a copolymer thereof) to the number of moles of amide groups (B) of a bislactam compound represented by the above formula (A) / ( B),
3. The nylon 6 resin composition according to claim 1, wherein the composition is blended so as to be 0.3 to 10.