JP2001031763A - Polyamide elastomer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyamide elastomer which is a block copolymer of a polyamide copolymer formed of a polyamide component and a polyester component in a specified ratio and a polyether and which is suitable for the use as boots, control cables, etc., especially in the automotive fields and as soft combs, etc., in the electrical fields. SOLUTION: This elastomer is a block copolymer of a polyamide copolymer comprising repeating units formed of 50-00 wt.% polyamide component represented by formula I or II, and 50-1 wt.% polyester component represented by formula III, and a polyether comprising repeating units represented by formula IV. In the formulas, R0, R1, and R3 are each a 2-10C alkylene; R2 is a 2-15C alkylene; R5 is a 2-8C alkylene; and R4 is a component comprising repeating units represented by -R-O- (wherein R is 2-8C alkylene), and has a number average mol.wt. of 500-5,000.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyamide elastomer having good flexibility and excellent mechanical properties at high temperatures.

[0002]

2. Description of the Related Art In recent years, materials excellent in oil resistance, chemical resistance, flexibility and the like have been desired in the fields of automobiles and various industries. In particular, there is a strong demand for materials for hoses and tubes having excellent oil resistance and gasoline resistance. At present, vulcanized rubber such as NBR and plasticized nylon are used for such applications. However, recently, as environmental issues have become very important and the demand for material recycling has increased,
The use of non-recyclable materials has been avoided, and the use of vulcanized rubber and the like has been restricted. Also, vulcanized rubber has many disadvantages in the production process.

On the other hand, plasticized nylon is disclosed in JP-A-60-1.
As disclosed in Japanese Patent No. 73047, this is a material in which flexibility is given to nylon. However, in a solvent having a strong affinity for a plasticizer, physical properties may change due to extraction of the plasticizer. Was. In addition, plasticization of nylon has certain limitations, and therefore has the disadvantage of not being able to cope with the required flexibility. Furthermore, the high glass transition temperature results in poor low-temperature properties such as low-temperature impact resistance and low-temperature elongation. Was enough.

As a resin for compensating for such a defect, for example, an amide-based elastomer which is a flexible nylon-based material has been proposed. This amide-based elastomer is a kind of thermoplastic elastomer, which has rubber elasticity at room temperature and is excellent in flexibility, but melts at a temperature higher than the melting point of nylon unlike vulcanized rubber. It is possible to perform thermoforming such as injection molding or extrusion molding in the same manner as described above, and it is also a material suitable for recycling.

[0005] An amide-based elastomer has a polyamide segment as a hard segment responsible for so-called physical crosslinking, and is a material excellent in physical properties such as oil resistance, chemical resistance, and heat resistance, which are characteristics of nylon. As such an amide-based elastomer, for example, polyetheramide and polyesteramide are known.

The above polyether amide is disclosed in, for example, JP-A-61-247732, which has a molecular weight of 800-800.
There is disclosed a method for producing by the polymerization of caprolactam in the presence of 5000 polyether segments. However, since a considerable proportion of polyether segments are introduced, the inherent chemical resistance of nylon is reduced, and the chemical resistance is reduced. It could not be used for applications characterized by In addition, because of its low heat resistance, it could not withstand continuous use at 150 ° C.

[0007]

SUMMARY OF THE INVENTION In view of the above, the present invention has high blockability, excellent oil resistance, chemical resistance and moldability, and particularly excellent flexibility and mechanical properties at high temperatures. An object is to provide a polyamide elastomer.

[0008]

The polyamide elastomer of the present invention comprises a repeating polyamide component represented by the general formula (1) or (2) and a polyester component represented by the general formula (3), The polyamide component is 50
-99% by weight, 50-1% by weight of the polyester component
And a block copolymer of a polyamide-based copolymer (A) and a polyether (B) composed of a repeating unit represented by the general formula (4).

Hereinafter, the present invention will be described in detail.

The polyamide copolymer (A) used in the present invention is composed of a repeating polyamide component represented by the general formula (1) or (2) and a polyester component represented by the general formula (3). You.

—CO—R ⁰ —CO—NH—R ¹ —NH— (1) —CO—R ² —NH—CO—R ² —NH— (2) — ^{CO-R 3 -CO-O-} R 4 - ····· (3)

In the formula, R ⁰ , R ¹ and R ^{3 each} have 2 to 10 carbon atoms.
R ² represents an alkylene group having 2 to 15 carbon atoms, and R ⁴ represents a repeating unit represented by —RO— (wherein, R represents an alkylene group having 2 to 8 carbon atoms). And a component having a number average molecular weight of 500 to 5,000.

The polyamide component represented by the above general formula (1) or (2) is used for the polycondensation of dicarboxylic acid and diamine,
It can be obtained by lactam polycondensation, amino acid polycondensation and the like. Examples of the lactam include caprolactam, enantholactam, dodecalactam, and undecanolactam, and examples of the amino acid include 11-aminoundecanoic acid and 12-aminododecanoic acid. These may be used alone or in combination of two or more.

Examples of the above dicarboxylic acids include succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanoic acid and the like, and ester derivatives thereof may be used. These may be used alone or in combination of two or more.

Examples of the diamine include ethylene diamine, trimethylene diamine, tetramethylene diamine, hexamethylene diamine, undecamethylene diamine and the like.

As the polyamide component, polyamide (nylon) 66 is preferable.

Examples of the polyamide copolymer (A) include, for example, a polyether obtained by reacting the above lactam or amino acid with a polyether, or reacting the above dicarboxylic acid or diamine with a polyether. Amide-based elastomers can be used.

Polyether (B) used in the present invention
Is composed of a repeating unit represented by the general formula (4).

—R ⁵ —O— (4) In the formula, R ⁵ represents an alkylene group having 2 to 8 carbon atoms.

As such a polyether (B),
For example, polyethylene glycol, poly 1,3-propylene glycol, poly 1,2-propylene glycol,
Polytetramethylene glycol, polyhexamethylene glycol and the like can be mentioned. Among these, polytetramethylene glycol is preferred from the viewpoint of excellent mechanical properties and weather resistance, and commercially available products include “PTH” manufactured by BASF.
F "and" PTMG "manufactured by Mitsubishi Chemical Corporation.

The number average molecular weight of the polyether (B) is preferably from 500 to 5,000, more preferably from 50 to 5,000.
0 to 2000. When the number average molecular weight is less than 500, the resulting polyester-based copolymer (A) has low blockability and a low melting point, so that the polyamide elastomer has low mechanical strength at high temperatures. When the number average molecular weight exceeds 5,000, the degree of polymerization of the polyamide elastomer does not increase due to low compatibility with the polyether (B), and an elastomer having sufficient strength cannot be obtained.

The above polyamide copolymer (A) can be polymerized, for example, by the following method. First, a dicarboxylic acid, a diamine, and a polyether (B) are transesterified by heating to 230 ° C. in the presence of a catalyst, and subsequently, a polycondensation reaction is performed at 270 ° C. under reduced pressure. Thereby, a polyamide-based copolymer (A) is obtained.

The proportion of the polyamide component in the components of the polyamide copolymer (A) is 50 to 99% by weight.
And preferably 70 to 95% by weight. If the amount of the polyamide component is less than 50% by weight, the melting point of the polyamide copolymer (A) is low, which adversely affects the mechanical strength of the polyamide elastomer at high temperatures. On the other hand, when the polyamide component exceeds 99% by weight, the compatibility with the polyether (B) is low, so that the degree of polymerization of the obtained polyamide elastomer does not increase, and a polyamide elastomer having sufficient strength cannot be obtained.

The polyamide elastomer of the present invention comprises a block copolymer of the above polyamide copolymer (A) and polyether (B). Such a block copolymer is obtained by converting the above-mentioned polyamide-based copolymer (A) and polyether (B) into any one of urethane-binding components (C) represented by general formulas (5) to (10). Obtained by combining them.

—NH—CO—NH—R ⁶ —NH—CO—O— (5) —CO—NH—R ⁷ —NH—CO—O— (6) — O—CO—NH—R ⁸ —NH—CO—O— (7) —NH—CO—NH—R ⁹ —NH—CO—NH— (8) —NH— ^{CO-NH-R 10 -NH-} CO- ····· (9) -CO-NH-R 11 -NH-CO- ····· (10)

In the formula, R ^{6 to} R ¹¹ represent a C 2 to C 15 alkylene group, a phenylene group or a methylene group or a functional group in which an alkylene group and a phenyl group are bonded.

The block copolymer bonded by the urethane bonding component (C) is obtained by reacting the polyamide copolymer (A) and the polyether (B) with a diisocyanate compound.

The number average molecular weight of the above polyether is 50
It is preferably from 0 to 5000, more preferably from 500 to 20.
00. When the number average molecular weight is less than 500, the obtained polyamide copolymer (A) has low blockability and low melting point, and the polyamide elastomer has low mechanical strength at high temperatures. When the number average molecular weight exceeds 5,000, the degree of polymerization of the polyamide elastomer does not increase due to low compatibility with the polyether (B), and an elastomer having sufficient strength cannot be obtained.

The structure of the diisocyanate compound is not particularly limited as long as it is a compound having two isocyanate groups in the same molecule. Compounds having the above isocyanate groups may be used.

Examples of the diisocyanate compound include aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate, tolylene diisocyanate, phenylene diisocyanate and naphthalene diisocyanate; 1,2-ethylene diisocyanate, 1,3-
Propylene diisocyanate, 1,4-butane diisocyanate, 1,6-hexamethylene diisocyanate,
Examples include 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, isophorone diisocyanate, and aliphatic diisocyanates such as hydrogenated 4,4′-diphenylmethane diisocyanate.

In the block copolymer of the present invention, if the blending amount of the polyether (B) is too small, a polyamide elastomer having sufficient flexibility cannot be obtained, and if the blending amount is too large, a polyamide having sufficient mechanical strength at a high temperature is not obtained. Since a system-based elastomer cannot be obtained, the amount is preferably 50 to 600 parts by weight, more preferably 100 to 300 parts by weight, based on 100 parts by weight of the polyamide-based copolymer (A).

When the amount of the urethane-binding component (C) is too small, the polyamide-based elastomer does not become a high-molecular-weight substance, so that the mechanical strength is low. When the amount is too large, the polyamide-based elastomer cannot have sufficient flexibility. The amount is preferably 10 to 100 parts by weight, more preferably 30 to 100 parts by weight, based on 100 parts by weight of the polyamide copolymer (A).
70 parts by weight.

In the polyamide elastomer of the present invention, the polyamide copolymer (A) and the polyether (B)
And to satisfy the amount of the urethane binding component (C),
The polyamide copolymer (A), the polyether (B) and the urethane binding component (C) may be reacted by melting and mixing at the above-mentioned weight ratio.

As a preferable method of the melt mixing, for example, a method of melt mixing in an extruder is mentioned, and a preferable melt mixing temperature is 180 to 280 ° C. If the melt mixing temperature is lower than 180 ° C, the reaction is difficult because the polyamide-based copolymer (A) does not melt. As a result, a polyamide elastomer having sufficient strength cannot be obtained.

In the present invention, a catalyst can be used at the time of melt-mixing the above-mentioned polyamide copolymer (A) and polyether (B) with the urethane binding component (C).
As the above catalyst, for example, diacyl stannous, tetraacyl stannic, dibutyltin oxide, dibutyltin dilaurate, dimethyltin malate, tin dioctanoate, tin tetraacetate, triethyleneamine, diethyleneamine, triethylamine, metal naphthenate, Metal octylate, triisobutylaluminum, tetrabutyltitanate, calcium acetate, germanium dioxide, antimony trioxide and the like may be used, and these may be used alone or in combination of two or more.

A stabilizer may be used in the polyamide-based elastomer, for example, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-).
Hydroxybenzyl) benzene, 3,9-bis {2-
[3- (3-t-butyl-4-hydroxy-5-methylphenyl) -propionyloxy] -1,1-dimethylethyl} -2,4,8,10-tetraoxaspiro [5,5]
Hindered phenolic antioxidants such as undecane; tris (2,4-di-t-butylphenyl) phosphite, trilauryl phosphite, 2-t-butyl-α-
(3-t-butyl-4-hydroxyphenyl) -p-cumenylbis (p-nonylphenyl) phosphite, dimyristyl 3,3'-thiodipropionate, distearyl 3,3'-thiodipropionate, pentaery Heat stabilizers such as styryltetrakis (3-laurylthiopropionate) and ditridecyl 3,3'-thiodipropionate are exemplified.

The ester-based elastomer of the present invention may be a fiber, an inorganic filler, a flame retardant, a UV absorber, an antistatic agent, an inorganic substance, or the like, as long as the practicality is not impaired during or after production.
An additive such as a higher fatty acid salt may be added.

As the above fibers, for example, glass fibers,
Examples include inorganic fibers such as carbon fiber, boron fiber, silicon carbide fiber, alumina fiber, amorphous fiber, and silicon / titanium / carbon fiber; and organic fibers such as aramid fiber. Examples of the inorganic filler include calcium carbonate, titanium oxide, mica, and talc. Examples of the flame retardant include hexabromocyclododecane, tris- (2,3-dichloropropyl) phosphate, and pentabromophenyl allyl ether.

As the above-mentioned ultraviolet absorber, for example, p-
tert-butylphenyl salicylate, 2-hydroxy-
4-methoxybenzophenone, 2-hydroxy-4-methoxy-2'-carboxybenzophenone, 2,4,5-
Trihydroxybutyrophenone and the like.

Examples of the antistatic agent include N, N
-Bis (hydroxyethyl) alkylamine, alkylallyl sulfonate, alkyl sulfanate and the like. As the inorganic substance, for example, barium sulfate,
Alumina, silicon oxide and the like can be mentioned. Examples of the higher fatty acid salt include sodium stearate, barium stearate, sodium palmitate and the like.

The polyamide elastomer of the present invention may be mixed with other thermoplastic resins and rubber components to modify its properties before use. As the thermoplastic resin,
For example, polyolefin, modified polyolefin, polystyrene, polyvinyl chloride, polyamide, polycarbonate, polysulfone, polyester and the like can be mentioned.

Examples of the rubber component include natural rubber, styrene-butadiene copolymer, polybutadiene,
Polyisoprene, acrylonitrile-butadiene copolymer, ethylene-propylene copolymer (EPM, EPD
M), polychloroprene, butyl rubber, acrylic rubber,
Examples include silicone rubber, urethane rubber, olefin-based thermoplastic elastomer, styrene-based thermoplastic elastomer, PVC-based thermoplastic elastomer, ester-based thermoplastic elastomer, and amide-based thermoplastic elastomer.

The polyamide-based elastomer of the present invention can be formed into a molded article by a commonly used molding method such as press molding, extrusion molding, injection molding, blow molding and the like. The molding temperature varies depending on the melting point of the polyamide elastomer and the molding method, but is suitably from 160 to 280 ° C. If the molding temperature is lower than 160 ° C., a uniform molded product cannot be obtained because the fluidity of the polyamide elastomer is low.
If the temperature exceeds ℃, the polyamide-based elastomer is decomposed, and an elastomer having sufficient strength cannot be obtained.

The molded article obtained by using the polyamide elastomer of the present invention is suitably used for, for example, automobile parts, electric and electronic parts, industrial parts, sports goods, medical goods and the like.

Examples of the automobile parts include boots such as constant velocity joint boots and rack and opinion boots; ball joint seals; safety belt parts; bumper fascia; emblem;
As the electric and electronic components, for example, a wire covering material,
Gears, rubber switches, membrane switches, tact switches, O-rings, and the like. Examples of the industrial component include a hydraulic hose, a coil tube, a sealing material, a packing, a V-belt, a roll, a vibration damping material, a shock absorber, a coupling, a diaphragm, and the like.

Examples of the sporting goods include shoe soles and ball balls. Examples of the medical supplies include a medical tube, a blood transfusion pack,
Catheters and the like. In addition to the above applications, elastic fibers,
It can be suitably used as an elastic sheet, a composite sheet, a hot melt adhesive, a material for alloying with other resins, and the like.

[0047]

In general, it is difficult for different polymer components to react with each other due to insufficient compatibility. However, in the polyamide elastomer of the present invention, the hard segment polyamide component and the soft segment polyether component are used. It is thought that by using a polyamide-based copolymer (A) obtained by copolymerizing the above and polyether (B) as a soft segment component, compatibility is improved and reactivity is extremely improved. As a result, an elastomer having high blockability between the hard segment component and the soft segment is generated.

In the polyamide-based elastomer, the crystal formed by the polyamide component constitutes a cross-linking point and exhibits properties as an elastomer. The elastomer is composed of a polyamide-rich portion and a polyether-rich portion, and the polyamide component is more easily crystallized than a conventional polyamide elastomer having the same degree of flexibility, and a strong crosslinking point is formed. Further, the presence of the polyether-rich portion increases the molecular weight between crosslink points. As a result, it shows good flexibility,
It becomes an elastomer material with excellent mechanical properties at high temperatures.

[0049]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples.

Example 1 100 parts by weight of adipic acid, 36 parts by weight of polytetramethylene glycol having a number average molecular weight of about 650 (“PTHF650” manufactured by BASF), 0.1 part by weight of tetrabutyl titanate as a catalyst, and a stabilizer as a stabilizer 1,3,5-trimethyl-2,4,6-tris (3
0.2 parts by weight of 5-di-t-butyl-4-hydroxybenzyl) benzene and 0.2 parts by weight of tris (2,4-di-t-butylphenyl) phosphite are added, and the reaction system is placed under nitrogen. At 230 ° C. for 1 hour to carry out transesterification. Next, after cooling to 100 ° C., 73 parts by weight of hexamethylenediamine was added, and the mixture was added under nitrogen stream for 2 hours.
After the temperature was raised to 0 ° C. and kept at 270 ° C. for 30 minutes, a decompression operation was performed. The polymerization system reached a reduced pressure of 2 mmHg or less in 20 minutes. As a result of performing a polycondensation reaction in this state for 20 minutes,
150 parts by weight of a white polyamide-based copolymer was obtained.

100 parts by weight of the polyamide copolymer,
110 parts by weight of polytetramethylene glycol having a number average molecular weight of about 1000 (“PTHF1000” manufactured by BASF) and 36 parts by weight of 4,4′-diphenylmethane diisocyanate were mixed with a twin-screw extruder (L / D manufactured by Berstorf Co., Ltd.).
= 25) to obtain a polyamide elastomer pellet at 240 ° C (residence time: 200 seconds).

Example 2 A polyamide elastomer pellet was obtained in the same manner as in Example 1 except that 16 parts by weight of polytetramethylene glycol and 73 parts by weight of hexamethylene diamine were used.

Example 3 Hexamethylenediamine was added to 8
Except for using 8 parts by weight, pellets of polyamide elastomer were obtained in the same manner as in Example 1.

Example 4 A polyamide elastomer pellet was obtained in the same manner as in Example 1, except that 32 parts by weight of polytetramethylene glycol and 66 parts by weight of hexamethylene diamine were used.

Comparative Example 1 100 parts by weight of adipic acid, 80 parts by weight of hexamethylenediamine, 0.1 part by weight of tetrabutyl titanate as a catalyst, and 1,3,5 as a stabilizer
-Trimethyl-2,4,6-tris (3,5-di-t-
Butyl-4-hydroxybenzyl) benzene 0.2 parts by weight and tris (2,4-di-t-butylphenyl)
0.2 parts by weight of phosphite is added, and the reaction
The temperature was raised to 270 ° C. over time, maintained at 270 ° C. for 30 minutes, and then reduced in pressure. Reaction system is 2mmHg in 20 minutes
The following degree of vacuum was reached: As a result of performing a polycondensation reaction in this state for 20 minutes, 130 parts by weight of a white polyamide-based copolymer was obtained. Next, pellets of polyamide elastomer were obtained from this polyamide copolymer in the same manner as in Example 1, but no pellet was obtained.

Comparative Example 2 100 parts by weight of adipic acid, 165 parts by weight of polytetramethylene glycol having a number average molecular weight of about 650 (“PTHF650” manufactured by BASF), 0.1 part by weight of tetrabutyl titanate as a catalyst, and a stabilizer as a stabilizer 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl)
0.2 parts by weight of benzene and tris (2,4-di-t
-Butylphenyl) phosphite 0.2 parts by weight,
The reaction system was maintained at 230 ° C. for 1 hour under nitrogen to carry out transesterification. Next, the reaction system was cooled to 100 ° C., 50 parts by weight of hexamethylene diamine was added, the temperature was raised to 270 ° C. over 2 hours in a nitrogen stream, and the temperature was maintained at 270 ° C. for 30 minutes, followed by pressure reduction. The polymerization system reached a reduced pressure of 2 mmHg or less in 20 minutes. In this state, a polycondensation reaction was performed for 20 minutes, and as a result, a colorless and transparent polyamide-based elastomer 250 was obtained.
Parts by weight were obtained.

The pellets obtained in the above Examples and Comparative Examples were press-molded (press temperature: 250 ° C.) to produce a sheet having a thickness of 2 mm, and the following items were evaluated using the sheet, and the results were shown in Table. 1 is shown. (1) Durometer hardness (Shore D) Measured at room temperature (23 ° C.) according to JIS K 7215. (2) Permanent compression strain Measured at 120 ° C. with a compression strain amount of 25% in accordance with JIS K6301. (3) Tensile strength The tensile strength at room temperature (23 ° C.) was measured according to JIS K6301.

[0058]

[Table 1]

[0059]

The polyamide-based elastomer of the present invention comprises:
With the above configuration, since the block has high blocking properties, it has good flexibility and excellent mechanical properties at high temperatures. Therefore, it is particularly suitably used for applications such as boots and control cables in the automobile field, and soft combs for dryers in the electric field.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hirotake Matsumoto 2-1 Hyakuyama, Shimamoto-cho, Mishima-gun, Osaka Sekisui Chemical Co., Ltd. F-term (reference) 4J001 DA01 DA02 DA04 DB05 DC02 DC03 DC05 DC12 EA06 EA07 EA08 EA16 EA17 EB04 EB05 EB06 EB07 EB08 EB09 EC04 EC05 EC06 EC07 EC08 EC09 ED63 ED64 ED65 FA03 FA05 FB03 FB05 FC03 FC05 GA11 HA01 HA02 HA04 HA05 JA02 JA05 JA07 JA10 JA12 JA15 JA18 JB13 JB25 JB32 J034 DL07 DL08 DL03 HC03 HC12 HC13 HC17 JA06 RA02 RA03 RA08 RA09 RA11 RA12 RA14 RA15

Claims (3)

[Claims] 1. A composition comprising a polyamide component represented by the general formula (1) or (2) and a polyester component represented by the general formula (3).
-99% by weight, 50-1% by weight of the polyester component
(A) and a block copolymer of a polyether (B) composed of a repeating unit represented by the general formula (4). —CO—R ⁰ —CO—NH—R ¹ —NH— (1) —CO—R ² —NH—CO—R ² —NH— (2) —CO—R ³ -CO-OR ⁴ -... (3) -R ⁵ -O- ... (4) wherein R ⁰ , R ¹ , and R ^{3 each} have 2 to 10 carbon atoms. An alkylene group, R ² represents an alkylene group having 2 to 15 carbon atoms, R ⁵ represents an alkylene group having 2 to 8 carbon atoms, and R ⁴ represents —R
Represents a component having a number average molecular weight of 500 to 5000, which is composed of a repeating unit represented by -O- (wherein R represents an alkylene group having 2 to 8 carbon atoms)] 2. The polyamide-based elastomer according to claim 1, wherein the polyamide component is polyamide 66. 3. The block copolymer comprises a polyamide copolymer (A) and a polyether (B) represented by the general formula (5)
(10) It is made of a compound bonded to any one kind of urethane bonding component (C), and 100 parts by weight of polyamide copolymer (A) and 50 to 60 of polyether (B).
The polyamide elastomer according to claim 1 or 2, comprising 0 parts by weight and 10 to 100 parts by weight of a urethane binding component (C). —NH—CO—NH—R ⁶ —NH—CO—O— (5) —CO—NH—R ⁷ —NH—CO—O— (6) —O—CO ^{-NH-R 8 -NH-CO-} O- ····· (7) -NH-CO-NH-R 9 -NH-CO-NH- ····· (8) -NH-CO-NH -R ¹⁰ -NH-CO- (9) -CO-NH-R ¹¹ -NH-CO- (10) [wherein, R ^{6 to} R ¹¹ have 2 to 2 carbon atoms. 15 alkylene groups,
Shows a functional group in which a phenylene group, a methylene group or an alkylene group and a phenyl group are bonded]