JP2017019913A - Thermoplastic polyurethane elastomer composition, flexible material and communication cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic polyurethane elastomer composition and a flexible material excellent in extensibility and tensile strength while maintaining abrasion resistance and slidability when making a molded article or coating a communication cable or a wire, and the communication cable excellent in extensibility and tensile strength while maintaining abrasion resistance and slidability.SOLUTION: The thermoplastic polyurethane elastomer composition contains a thermoplastic polyurethane elastomer of 100 pts.mass and acryl modified organopolysiloxane of 1 to 100 pts.mass.SELECTED DRAWING: None

Description

  The present invention relates to a thermoplastic polyurethane elastomer composition, a flexible material, and a communication cable.

Conventionally, vulcanized rubber and vinyl chloride resin have been used as molding materials for automobile parts, electronic / electric equipment parts and the like, and as covering materials for communication cables and electric wires. These molded products, communication cables, electric wires, and the like are required to have wear resistance. For example, when a communication cable is used in a device such as a robot arm, the communication cable moves following the operation of the device. Therefore, slidability is also required especially for the outermost layer (sheath) of the communication cable.
However, vulcanized rubber and vinyl chloride resin do not fully satisfy wear resistance and sliding properties.

  As a resin excellent in wear resistance and slidability, for example, Patent Document 1 discloses an olefinic thermoplastic elastomer composition obtained by blending an olefinic thermoplastic elastomer with an acrylic-modified organopolysiloxane.

Japanese Patent No. 3437466

By the way, since a communication cable used for a device such as a robot arm is pulled following the operation of the device, stretchability and tensile strength are also required.
However, the olefinic thermoplastic elastomer composition described in Patent Document 1 does not necessarily satisfy elongation and tensile strength, and is unsuitable for coating communication cables.

  The present invention has been made in view of the above circumstances, and when it is formed into a molded product or when a communication cable or electric wire is covered, it maintains heat resistance and slidability while maintaining excellent extensibility and tensile strength. An object is to provide a plastic polyurethane elastomer composition and a flexible material, and a communication cable excellent in stretchability and tensile strength while maintaining wear resistance and slidability.

The present invention has the following aspects.
[1] A thermoplastic polyurethane elastomer composition containing a thermoplastic polyurethane elastomer and 1 to 100 parts by mass of an acrylic-modified organopolysiloxane with respect to 100 parts by mass of the thermoplastic polyurethane elastomer.
[2] The thermoplastic polyurethane elastomer composition according to [1], further containing 0.01 to 10 parts by mass of metal soap with respect to 100 parts by mass of the thermoplastic polyurethane elastomer.
[3] A flexible material comprising the thermoplastic polyurethane elastomer composition according to [1] or [2].
[4] A communication cable having a surface coated with the flexible material according to [3].

When the thermoplastic polyurethane elastomer composition and the flexible material of the present invention are formed into a molded product or covered with a communication cable or an electric wire, the thermoplastic polyurethane elastomer composition and the flexible material maintain the wear resistance and the sliding property while maintaining the stretchability and the tensile strength. Excellent.
Further, the communication cable of the present invention is excellent in stretchability and tensile strength while maintaining wear resistance and slidability.

"Thermoplastic polyurethane elastomer composition"
The thermoplastic polyurethane elastomer composition of the present invention contains a thermoplastic polyurethane elastomer and an acrylic-modified organopolysiloxane. The thermoplastic polyurethane elastomer composition preferably further contains a metal soap.
Hereinafter, each component will be described.

<Thermoplastic polyurethane elastomer>
As the thermoplastic polyurethane elastomer (hereinafter also referred to as “TPU”), a block copolymer having a hard segment block and a soft segment block as repeating units is preferable.

The hard segment block is preferably composed of at least diisocyanate and diols.
Examples of the diisocyanate include 1,6-hexamethylene diisocyanate (HDI), 4,4′-diphenylmethane diisocyanate (MDI), 1,5-naphthylene diisocyanate (NDI), isophorone diisocyanate (IPDI), xylene diisocyanate (XDI), Examples include hydrogenated XDI, tolylene diisocyanate (TDI), triisocyanate, tetramethylxylene diisocyanate (TMXDI), 1,3,6-hexamethylene triisocyanate.

  Examples of the diol include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 1,8-octanediol, 1,9-nonanediol, diethylene glycol, dipropylene glycol, Examples include tripropylene glycol.

The soft segment block is preferably composed of at least a polyol and a diisocyanate.
Examples of the polyol include polyester polyol, polyether polyol, and polycarbonate polyol.

Examples of polyester polyols include polyester polyols obtained by condensation polymerization of diols and dicarboxylic acids; polylactone diols obtained by ring-opening polymerization of lactone monomers such as ε-caprolactone.
Examples of the diol include diols exemplified above in the description of the hard segment block.
Examples of the dicarboxylic acid include succinic acid, adipic acid, sebacic acid, phthalic acid, terephthalic acid, and isophthalic acid.

Examples of the polyether polyol include polyether polyols obtained by condensation polymerization of dicarboxylic acid and glycol; polyethylene glycol; polypropylene glycol; polytetramethylene glycol.
Examples of the dicarboxylic acid include the dicarboxylic acids exemplified above in the description of the polyester polyol.
Examples of glycols include diethylene glycol and propylene oxide adducts.

Examples of the polycarbonate polyol include polycarbonate polyol obtained by reaction of diols and carbonates; a copolymer of polycaprolactone polyol and polyhexamethylene carbonate, and the like.
Examples of the diol include diols exemplified above in the description of the hard segment block.
Examples of carbonates include diethylene carbonate and diethyl carbonate.

  Commercially available products can be used as the TPU, such as “T-8185N” manufactured by DCI Bayer Polymer Co., Ltd., “ET870-11V” manufactured by BASF Japan Ltd., and the like.

<Acrylic modified organopolysiloxane>
As the acrylic modified organopolysiloxane, an organopolysiloxane represented by the following general formula (1) is obtained by emulsion graft copolymerization of an acrylic ester, and an organopolysiloxane represented by the following general formula (1). A product obtained by emulsion graft copolymerization of a mixture of an acrylate ester and a monomer copolymerizable therewith is preferred.

In the general formula ^{(1), R 1, R} 2 and ^{R 3} are the same or different halogenated hydrocarbon group or a hydrocarbon group having 1 to 20 carbon atoms having 1 to 20 carbon atoms.
Examples of the hydrocarbon group having 1 to 20 carbon atoms include alkyl groups such as a methyl group, an ethyl group, a propyl group, and a butyl group; and aryl groups such as a phenyl group, a tolyl group, a xylyl group, and a naphthyl group.
Examples of the halogenated hydrocarbon group having 1 to 20 carbon atoms include those in which at least one hydrogen atom bonded to a carbon atom of the hydrocarbon group is substituted with a halogen atom.

In the general formula (1), Y is an organic group having a radical reactive group, an SH group, or both.
Examples of the radical reactive group include a vinyl group, an allyl group, a γ-acryloxypropyl group, a γ-methacryloxypropyl group, and a γ-mercaptopropyl group.

In the general formula (1), Z ¹ and Z ² are the same or different hydrogen atoms, lower alkyl groups, or triorganosilyl groups.
Examples of the lower alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group.
The triorganosilyl group is represented by the following general formula (2).

In the general formula (2), R ⁴ and R ⁵ are the same or different hydrocarbon groups having 1 to 20 carbon atoms or halogenated hydrocarbon groups having 1 to 20 carbon atoms, and R ⁶ has 1 carbon atom. An organic group having a hydrocarbon group of ˜20, a halogenated hydrocarbon group of 1 to 20 carbon atoms, a radical reactive group, an SH group, or both.
These organic groups having a hydrocarbon group having 1 to 20 carbon atoms, a halogenated hydrocarbon group having 1 to 20 carbon atoms, a radical reactive group, an SH group, or both are represented by the above R ¹ , R ² , R ³ and The same thing as what was illustrated previously in description of Y can be mentioned.

  In the general formula (1), m is a positive integer of 10,000 or less, preferably an integer in the range of 500 to 8,000, and n is an integer of 1 or more, preferably 1 to 1. An integer in the range of 500.

  Examples of the acrylic ester that is emulsion graft copolymerized with the organopolysiloxane include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, isobutyl acrylate, pentyl acrylate, hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, Examples include acrylic acrylates such as stearyl acrylate; alkoxyalkyl acrylates such as methoxyethyl acrylate and butoxyethyl acrylate; cyclohexyl acrylate, phenyl acrylate, and benzyl acrylate. These are used singly or in combination of two or more.

  Examples of the monomer copolymerizable with the acrylic ester include hydroxyl group-containing unsaturated monomers such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate. These are used singly or in combination of two or more.

The mixing ratio ((a) / (b)) of the organopolysiloxane (a) and the acrylic acid ester or the mixture of the acrylic acid ester and the monomer copolymerizable therewith ((a) / (b)) is expressed in mass ratio. 2/8 to 8/2 is preferable, and 4/6 to 7/3 is more preferable.
Moreover, when using a mixture of an acrylate ester and a monomer copolymerizable therewith as (b), the content of the monomer copolymerizable with the acrylate ester relative to the total mass of the mixture is: It is preferable that it is less than 30 mass%.

  Commercially available products can be used as the acrylic-modified organopolysiloxane, and examples thereof include “Charine R-170”, “Charine R-170S”, and “Charine R-127E” manufactured by Nissin Chemical Industry Co., Ltd.

  Content of acrylic modified organopolysiloxane is 1-100 mass parts with respect to 100 mass parts of TPU, 5-80 mass parts is preferable, and 10-50 mass parts is more preferable. When the content of the acryl-modified organopolysiloxane is 1 part by mass or more, an effect of improving wear resistance and slidability can be obtained. In particular, when the content of the acrylic-modified organopolysiloxane is 5 parts by mass or more, a drip prevention effect during combustion can be obtained. These effects of improving wear resistance and slidability and anti-drip effect tend to increase as the content of acrylic-modified organopolysiloxane increases. However, if the content is too high, the acrylic-modified organopolysiloxane tends to aggregate in TPU. When the acrylic-modified organopolysiloxane aggregates, cracks may be generated based on the aggregated portion. In addition, the extensibility and tensile strength are likely to decrease. If the content of the acryl-modified organopolysiloxane is 100 parts by mass or less, the acryl-modified organopolysiloxane can be prevented from aggregating in TPU, so that cracks are hardly generated. Also, the extensibility and tensile strength can be maintained well.

<Metal soap>
Metal soap is a metal salt of a fatty acid.
Examples of fatty acids include butyric acid, valeric acid, caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, octylic acid, arachidic acid, arachidonic acid, behenic acid, naphthenic acid An acid etc. are mentioned.
Examples of the metal include potassium, magnesium, calcium, barium, manganese, cobalt, nickel, copper, zinc, and lithium.
Specific examples of the metal soap include calcium behenate, calcium stearate, and lithium stearate. These are used singly or in combination of two or more. Among these, calcium behenate is preferable from the viewpoint of compatibility with TPU, specifically, metal releasability and non-blooming.

  0.01-10 mass parts is preferable with respect to 100 mass parts of TPU, as for content of metal soap, 0.01-1.0 mass part is more preferable, and 0.1-1.0 mass part is especially preferable. When the content of the metal soap is 0.01 parts by mass or more, the acrylic-modified organopolysiloxane is easily dispersed uniformly in the TPU, and the wear resistance and slidability can be maintained well. Moreover, it can suppress that acrylic modified organopolysiloxane aggregates in TPU. On the other hand, if the content of the metal soap is 10 parts by mass or less, the moldability can be maintained well.

<Optional component>
The thermoplastic polyurethane elastomer composition may contain components (optional components) other than TPU, acrylic-modified organopolysiloxane, and metal soap as necessary.
Examples of optional components include softeners such as process oil, fillers such as talc, carbon black, and calcium carbonate, various additives such as ultraviolet absorbers, antioxidants, processing stabilizers, and colorants.

<Effect>
The TPU described above is a component that mainly contributes to elongation and tensile strength, and the acrylic-modified organopolysiloxane is a component that mainly contributes to wear resistance and slidability.
Since the thermoplastic polyurethane elastomer composition of the present invention has both TPU and a specific amount of acrylic-modified organopolysiloxane, it is resistant to wear and sliding when formed into a molded product or when a communication cable or wire is covered. Excellent extensibility and tensile strength while maintaining the properties.
In particular, if the thermoplastic polyurethane elastomer composition also contains a metal soap, it becomes easy to uniformly disperse the acrylic-modified organopolysiloxane in TPU, and the wear resistance and slidability can be maintained well. Moreover, since it can suppress that acrylic modified organopolysiloxane aggregates in TPU, a crack is hard to generate | occur | produce.

"Flexible materials"
The flexible material of the present invention comprises the above-described thermoplastic polyurethane elastomer composition of the present invention. Therefore, a molded product formed by molding the flexible material of the present invention, or a communication cable or electric wire whose surface is coated with the flexible material of the present invention has excellent stretchability and slidability while maintaining wear resistance and slidability. Excellent tensile strength.
The flexible material of the present invention is suitable for molding materials such as automobile parts and electronic / electric equipment parts, and covering materials for communication cables and electric wires. Since the flexible material of the present invention is excellent in wear resistance, slidability, elongation and tensile strength, it is particularly suitable as a coating material for communication cables.

"communication cable"
The communication cable of the present invention is coated on the surface with the above-described flexible material of the present invention.
The configuration of the communication cable is not particularly limited as long as the outermost layer (sheath layer) is formed of the flexible material of the present invention. For example, the outer periphery of the core wire in which the outer periphery of the conductor wire is covered with an insulator Examples include a structure coated with the flexible material of the invention.

Since the surface of the communication cable of the present invention is coated with the flexible material of the present invention, it is excellent in stretchability and tensile strength while maintaining wear resistance and slidability.
The communication cable of the present invention is suitable as a communication cable used in devices such as robot arms, automatic assembly machines, game machine cranes, etc., and is excellent in slidability even if the communication cable moves following the operation of these devices. So the surface is hard to wear. Moreover, since the communication cable of the present invention is excellent in stretchability and tensile strength, it is difficult to cut even if the communication cable is pulled following the operation of these devices.

  EXAMPLES Hereinafter, although an Example is shown and this invention is demonstrated concretely, this invention is not limited to description of these Examples.

"Example 1"
100 parts by mass of a thermoplastic polyurethane elastomer (D-C Bayer Polymer Co., Ltd., “T-8185N”) and an acrylic modified organopolysiloxane (manufactured by Nissin Chemical Industry Co., Ltd., “Charine R-170S”, (a) / ( b) = 7/3) 1 part by mass was mixed to obtain a thermoplastic polyurethane elastomer composition.
The obtained thermoplastic polyurethane elastomer composition was kneaded for 7 minutes at 170 ° C. using two 3.5 inch test rolls to obtain a roll sheet molded product. This was sandwiched between mirror plates, preheated at 170 ° C. for 4 minutes, and then pressurized at 150 kg / cm ² for 4 minutes to produce a 1.0 mm thick sheet-like test piece (120 mm × 120 mm). .
About the obtained test piece, various measurement and evaluation were performed by the method shown below. The results are shown in Table 1.

<Measurement / Evaluation>
(Measurement of hardness)
The Shore A hardness of the test piece was measured according to JIS K 6253-3: 2012.

(Evaluation of slidability and wear resistance)
Using a friction tester (manufactured by Shinto Kagaku Co., Ltd., “Haydon 14D-ANL”), the static friction coefficient and the dynamic friction coefficient of the test piece were measured under the conditions of a SUS steel ball having a diameter of 10 mm, a load of 50 g, and a tensile speed of 100 mm / min. . It means that it is excellent in slidability and abrasion resistance, so that a friction coefficient is low.

(Tensile test)
In advance, a test piece was punched with a dumbbell No. 5 type of JIS K 6251, and a 25 mm mark was entered.
Using a shopper type tensile tester, the test piece was pulled at a tensile rate of 200 mm / min and a temperature of 23 ° C., and the 100% modulus was measured. Moreover, the maximum load required for the test piece to break was defined as tensile strength (breaking strength). Moreover, the distance between marked lines when the test piece broke was measured to obtain the elongation percentage.

(Evaluation of flammability)
A test piece was cut into a strip of 1.0 mm × 120 mm, a thin material vertical combustion test (VTM test) was performed in accordance with the UL94 standard, and the flammability was evaluated according to the following evaluation criteria.
(Double-circle): The form was hold | maintained at the time of combustion.
○: The shape was slightly retained during combustion.
X: Drip occurred.

"Examples 2-7, Comparative Examples 1-3"
A thermoplastic polyurethane elastomer composition was prepared in the same manner as in Example 1 except that the blending composition shown in Table 1 was changed, and test pieces were prepared and subjected to various measurements and evaluations. The results are shown in Table 1.

“Comparative Example 4”
100 parts by mass of an olefin-based thermoplastic elastomer (Mitsui Chemical Co., Ltd., “Milastomer 7030BS”) and an acrylic-modified organopolysiloxane (Nisshin Chemical Co., Ltd., “Charine R-170S”, (a) / (b) = 7/3) 10 parts by mass and 0.5 parts by mass of calcium behenate as a metal soap were mixed to obtain an olefin-based thermoplastic elastomer composition.
Except having used the obtained olefin type thermoplastic elastomer composition, the test piece was produced similarly to Example 1, and various measurement and evaluation were performed. The results are shown in Table 1.

  As is apparent from Table 1, molded articles having excellent wear resistance, slidability, stretchability and tensile strength were obtained from the thermoplastic polyurethane elastomer compositions obtained in the respective examples. In particular, in Examples 2 to 7 in which 5 parts by mass or more of acrylic-modified organopolysiloxane was used, the anti-drip effect was also excellent.

On the other hand, in the case of Comparative Example 1 in which the acrylic-modified organopolysiloxane and the metal soap were not used, the moldability was lowered and a test piece could not be produced.
In the case of Comparative Example 2, a test piece could be prepared because a metal soap was used, but since an acrylic-modified organopolysiloxane was not used, it was inferior in slidability and wear resistance.
In the case of Comparative Example 3 in which 150 parts by mass of the acrylic-modified organopolysiloxane was used, the extensibility and the tensile strength were inferior.
In the case of the comparative example 4 which used the olefin type thermoplastic elastomer instead of the thermoplastic polyurethane elastomer, it was inferior to elongation property and tensile strength.

Claims (4)

  A thermoplastic polyurethane elastomer composition comprising a thermoplastic polyurethane elastomer and 1 to 100 parts by mass of an acrylic-modified organopolysiloxane with respect to 100 parts by mass of the thermoplastic polyurethane elastomer.   The thermoplastic polyurethane elastomer composition according to claim 1, further comprising 0.01 to 10 parts by mass of a metal soap with respect to 100 parts by mass of the thermoplastic polyurethane elastomer.   A flexible material comprising the thermoplastic polyurethane elastomer composition according to claim 1.   A communication cable having a surface coated with the flexible material according to claim 3.