JP7248442B2 - Method for producing thermoplastic elastomer composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a thermoplastic elastomer composition containing a crosslinkable rubber and an olefinic polymer.

Conventionally, there is known a method of producing a thermoplastic elastomer by dynamically heat-treating an ethylene/α-olefin/non-conjugated polyene copolymer and a polyolefin resin in the presence of a cross-linking agent using a batch-type mixer. (Patent Document 1). However, it has been difficult to apply the conventional method to oil-resistant rubber, which has a different cross-linking behavior from ethylene/α-olefin/non-conjugated polyene copolymer. In addition, the method could not be applied to a system in which the reaction activity greatly changes in the presence of a cross-linking agent whose parameters such as activation energy are unknown, or a cross-linking aid such as a cross-linking accelerator or a cross-linking retarder. On the other hand, as a method to know the cross-linking characteristics of cross-linked rubber, there is a method of measuring the cross-linking curve according to JIS K6300-2, but the conventional method can only estimate the cross-linking behavior at a constant temperature, and it is possible to estimate the cross-linking behavior sequentially by kneading. It could not be applied to systems where the temperature changes.

WO2016/158612

An object of the present invention is to provide a process for producing a thermoplastic elastomer composition comprising a crosslinked polar rubber and an olefinic polymer, both of which are highly dispersed in each other, and excellent in moldability and other properties. aim.

The gist of the present invention relates to the following [1] to [12].

[1] carbodiimide group-containing compound (A),
an olefin-based polymer (B) having a group that reacts with a carbodiimide group;
polar rubber (C),
an olefinic polymer (D) and a cross-linking agent (E) capable of cross-linking the polar rubber (C),
A method for producing a thermoplastic elastomer composition comprising a step of dynamically crosslinking using a batch type kneader under conditions satisfying the following conditions (1) to (3).
(1) Tmax. ≧T1
(“Tmax.” is the maximum resin temperature (° C.) from when the cross-linking agent (E) is introduced into the batch kneader until the thermoplastic elastomer composition is discharged from the batch kneader. ” is the temperature (° C.) defined by the following formula (i).)
T1=ΔE/(8.314×(LnA−3))−273.15 (i)
(“ΔE” is the activation energy (J/mol) calculated from the slope of the Arrhenius plot created from the cross-linking curves measured at multiple temperatures using the polar rubber (C) and the cross-linking agent (E). ” is the frequency factor (hr ⁻¹ ) calculated from the intercept.)
(2) T2≤T3
(“T2” is the resin temperature (° C.) in the kneader when the cross-linking agent (E) is introduced into the batch type kneader, and “T3” is the temperature (° C.) defined by the following formula (ii). .)
T3=ΔE/(8.314×(LnA−5))−273.15 (ii)
(3) 2.0 ≤ P1 ≤ 8.5
("P1" is a value defined by the following formula (iii).)
P1=LnA−ΔE/(8.314×(Tave.+273.15)) (iii)
("Tave." is the average value (°C) of the resin temperature from the state in which the cross-linking agent (E) is present and the olefinic polymer (D) is molten to the completion of kneading and discharge.)

[2] The composition in the dynamic cross-linking step contains a reaction product (I) of a carbodiimide group-containing compound (A) and an olefinic polymer (B) having a group that reacts with a carbodiimide group, [ 1].

[3] The method for producing a thermoplastic elastomer composition according to any one of [1] or [2], wherein the polar rubber (C) contains a polar rubber (C1) having a group that reacts with a carbodiimide group.

[4] The method for producing a thermoplastic elastomer composition according to [3], wherein the polar rubber (C1) having a group that reacts with a carbodiimide group is a polar rubber having a group having an active hydrogen in its side chain.

[5] The thermoplastic elastomer composition according to [3] or [4], which contains a reaction product (II) of a carbodiimide group-containing compound (A) and a polar rubber (C1) having a group that reacts with a carbodiimide group. A method of making things.

[6] The method for producing a thermoplastic elastomer composition according to any one of [1] to [5], wherein the carbodiimide group-containing compound (A) is polycarbodiimide having a repeating unit represented by the following general formula.
-N=C=N-R ¹ -
(In the formula, R ¹ represents a divalent organic group.)

[7] The olefin-based polymer (B) having a group that reacts with a carbodiimide group is an olefin-based polymer having a group having an active hydrogen in its side chain, according to any one of [1] to [6]. A method for producing a thermoplastic elastomer composition.

[8] [1] to [7], wherein the olefin polymer (B) having a group reactive with a carbodiimide group is a graft copolymer of a polyolefin and a compound (b) having a group reactive with a carbodiimide group. ] The method for producing a thermoplastic elastomer composition according to any one of ].

[9] The method for producing a thermoplastic elastomer composition according to any one of [1] to [8], wherein the olefin polymer (D) is a propylene polymer.

[10] For a total of 100 parts by mass of the olefinic polymer (B) having a group that reacts with the carbodiimide group, the polar rubber (C), and the olefinic polymer (D), the composition in the dynamic crosslinking step hand,
The method for producing a thermoplastic elastomer composition according to any one of [1] to [9], wherein the carbodiimide group-containing compound (A) is blended in the range of 0.01 to 30 parts by mass.

[11] The method for producing a thermoplastic elastomer composition according to any one of [1] to [10], wherein the batch kneader has an intermeshing rotor.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a method for producing a thermoplastic elastomer composition having the elasticity of a crosslinked polar rubber and excellent properties such as moldability and mechanical properties. The thermoplastic elastomer composition produced according to the present invention contains a crosslinked polar rubber and an olefinic polymer, both of which are highly dispersed in each other.

[Production method]
The production method of the present invention includes a carbodiimide group-containing compound (A), an olefinic polymer (B) having a group that reacts with a carbodiimide group, a polar rubber (C), an olefinic polymer (D), and the polar rubber ( A step of dynamically cross-linking a cross-linking agent (E) capable of cross-linking C) using a batch kneader under conditions satisfying the following conditions (1) to (3). Conditions (1) to (3) will be described below.

Condition (1): Tmax. ≧T1
In the condition (1), "Tmax." is the maximum value (°C) of the resin temperature from the introduction of the cross-linking agent (E) into the batch kneader until the thermoplastic elastomer composition is discharged from the batch kneader. and "T1" is the temperature (°C) defined by the following formula (i).

T1=ΔE/(8.314×(LnA−3))−273.15 (i)
In formula (i), "ΔE" is the activation energy (J/mol) calculated from the slope of the Arrhenius plot created from the cross-linking curves measured at multiple temperatures using the polar rubber (C) and the cross-linking agent (E). and “A” is the frequency factor (hr ⁻¹ ) calculated from the intercept.

The cross-linking curve under condition (1) can be measured using a rotorless vulcanization tester or the like. The cross-linking curve can be measured according to JIS K6300-2 using the polar rubber (C) and a cross-linking agent (E) capable of cross-linking the polar rubber (C) and/or a cross-linking aid. When multiple polar rubbers (C) are used in combination, it is preferable to measure the ratio of the rubbers actually used, but it is also possible to use the value measured for the component with the highest usage ratio among the polar rubbers (C). can. Specifically, the difference between the minimum value ML and the maximum value MH of the torque obtained by measuring the cross-linking curve is determined as ME, and t'c(90) at 90% ME is determined to obtain the cross-linking speed. Activation energy ΔE (J/mol) can be calculated from the slope of the straight line and frequency factor A (hr ⁻¹ ) can be calculated from the intercept by plotting the cross-linking rates obtained from a plurality of measured temperatures by Arrhenius plotting. At this time, if there is no maximum point in the cross-linking curve, or if it is difficult to find the maximum torque value MH because the equilibrium state is not reached, refer to "Rubber Technology Basics" (edited by the Japan Rubber Association, p291- 292) is preferably used as the maximum torque value MH. Specifically, several cross-linking times are selected, the slope of the tangent line of the cross-linking curve at that cross-linking time is obtained, and the slope of the tangent line plotted on the vertical axis against the torque on the horizontal axis is extrapolated to the horizontal axis. can be used as the maximum torque value MH.

Tmax. under condition (1). (°C) is less than T1 (°C), the reaction temperature is insufficient and the mechanical properties deteriorate.

Under condition (1), Tmax. (° C.) is T1 (° C.) or higher, and the difference between the two (Tmax.-T1) is preferably 5° C. or higher, more preferably 10° C. or higher.

Condition (2): T2 ≤ T3
In condition (2), "T2" is the resin temperature (°C) in the kneader when the cross-linking agent (E) is introduced into the batch kneader, and "T3" is the temperature defined by the following formula (ii). (°C).

T3=ΔE/(8.314×(LnA−5))−273.15 (ii)
"ΔE" and "A" in formula (ii) have the same meanings as "ΔE" and "A" in formula (i) described above.

If T2 (° C.) in condition (2) is higher than T3 (° C.), the cross-linking reaction proceeds locally, so that a uniform composition cannot be obtained and moldability deteriorates.

In condition (2), T2 should be T3 or less, but the difference between the two (T3-T2) is preferably 5°C or more, more preferably 10°C or more.

Condition (3): 2.0 ≤ P1 ≤ 8.5
In condition (3), "P1" is a value defined by the following formula (iii).

P1=LnA−ΔE/(8.314×(Tave.+273.15)) (iii)
In the formula (iii), "Tave." is the average resin temperature (° C. ). "ΔE" and "A" have the same meanings as "ΔE" and "A" in formula (i) described above.

"The state in which the olefin polymer (D) is molten" in "Tave." of the formula (iii) is the state when the resin temperature reaches or exceeds its melting point. In addition, when the olefin polymer (D) is composed of a plurality of components, "Tave." The average value of the resin temperature up to

In condition (3), when P1 is less than 2.0, the crosslinking reaction is insufficient and the mechanical properties deteriorate, and when P1 is greater than 8.5, the deterioration of the resin progresses and the mechanical properties and heat aging resistance deteriorates.

Condition (3) preferably satisfies 2.0≦P1≦8.2, and more preferably satisfies 2.2≦P1≦8.2.

The batch type kneader is not particularly limited, and any type of kneader may be used as long as it is a batch type.

There are no particular restrictions on the shape of the rotor of the batch kneader, but an intermeshing rotor is preferred. An intermeshing rotor has a structure in which two rotors are meshed with each other, and kneading is performed not only between the rotor and the chamber wall surface, but also between the rotors. is possible. Kneaders with intermeshing rotors are commonly called intermeshing mixers. By using a batch type kneader with an intermeshing rotor, it is possible to sufficiently disperse the island phase while controlling kneading and dynamic cross-linking. Thermoplastic elastomer compositions with better appearance and better mechanical properties can be produced. In the following description, a batch kneader having such an intermeshing rotor is referred to as an "intermeshing kneader".

The intermeshing kneader is preferably a closed kneading device. Specific examples thereof include intermeshing kneaders manufactured by Kobe Steel, Ltd. and Harburg-Freudenberger Maschinenbau GmbH.

Each component used as a raw material for the thermoplastic elastomer composition produced according to the present invention will be described below.

[Carbodiimide group-containing compound (A)]
The carbodiimide group-containing compound (A) used in the present invention is not particularly limited as long as it is a compound having a carbodiimide group represented by -N=C=N-, but is preferably represented by the following general formula. Polycarbodiimide with the repeat units shown.
-N=C=N-R ¹ -
(In the formula, R ¹ represents a divalent organic group.)

Although the method for synthesizing polycarbodiimide is not particularly limited, for example, polycarbodiimide can be synthesized by reacting an organic polyisocyanate in the presence of a catalyst that accelerates the carbodiimidation reaction of isocyanate groups.

When the carbodiimide group-containing compound (A) is polycarbodiimide, its polystyrene-reduced number average molecular weight (Mn) determined by gel permeation chromatography (GPC) is usually 400 to 500,000, preferably 1,000 to 10. ,000, more preferably 2,000 to 4,000. When the number average molecular weight (Mn) is within this range, each component in the composition exhibits good compatibility, and the resulting thermoplastic elastomer composition has rubber elasticity and oil resistance, and is also excellent in moldability. It becomes a thing.

The carbodiimide group-containing compound (A) may be used alone or in combination. For example, polycarbodiimide alone may be used, polycarbodiimide and monocarbodiimide may be used in combination, or monocarbodiimide alone may be used. In the present invention, the carbodiimide group-containing compound (A) preferably contains polycarbodiimide.

As the carbodiimide group-containing compound (A), a commercially available carbodiimide group-containing compound can be used as it is. Examples of commercially available carbodiimide group-containing compounds include Carbodilite (registered trademark) HMV-8CA, HMV-15CA and LA1 manufactured by Nisshinbo Chemical Co., Ltd.

The carbodiimide group content in the carbodiimide group-containing compound (A) and in the resulting reaction product or thermoplastic elastomer composition can be measured by ¹³ C-NMR, IR, titration, etc., and is understood as a carbodiimide equivalent. Is possible. It is possible to observe peaks at 130 to 142 ppm in ¹³ C-NMR and 2130 to 2140 cm ^-1 in IR.

[Olefin-based polymer (B) having a group that reacts with a carbodiimide group]
The olefin-based polymer (B) having a group that reacts with a carbodiimide group, which is used in the present invention, is not particularly limited. can be obtained by introducing a group that reacts with into the polyolefin. Here, the "group reactive with a carbodiimide group" includes, for example, a group having an active hydrogen, or a group that can be easily converted to a group having an active hydrogen with water or the like.

As a method for introducing a group that reacts with a carbodiimide group into a polyolefin, a well-known method can be adopted. and a method of radically copolymerizing a compound (b) having a group reactive with a carbodiimide group and an olefin. Among them, graft copolymerization is preferred.

Hereinafter, the case of obtaining the olefin polymer (B) having a group that reacts with the carbodiimide group by graft copolymerization and the case of obtaining it by radical copolymerization will be specifically described.

(graft copolymerization)
The olefin-based polymer (B) having a group that reacts with a carbodiimide group in a side chain is a compound (B) that has a group that reacts with a carbodiimide group ( b) can be obtained by graft copolymerization.

<Unmodified polyolefin (polyolefin main chain)>
The unmodified polyolefin used as the polyolefin main chain is, for example, a polymer mainly composed of an aliphatic α-olefin having 2 to 20 carbon atoms, a cyclic olefin, or a non-conjugated diene, preferably having 2 to 10 carbon atoms. It is a polymer mainly composed of α-olefin, more preferably 2 to 8 α-olefins. These olefins may be used singly or in combination of two or more. In the present invention, homopolymers or copolymers of ethylene, propylene, 1-butene, 4-methyl-1-pentene, 3-methyl-1-butene, 1-hexene, 1-octene, tetracyclododecene and norbornene Coalescence can preferably be used. In addition, they can be used in both isotactic and syndiotactic structures, and stereoregularity is not particularly limited.

In the thermoplastic elastomer composition produced according to the present invention, the carbodiimide group-containing compound (A), which is a raw material, is an olefin polymer (B) having a group that reacts with the carbodiimide group [and a polar rubber (C), which will be described later. contains a polar rubber (C1) having a group that reacts with a carbodiimide group, the polar rubber (C1)] reacts with the polar rubber (C1)] by melt-kneading, and the resulting reactant acts as a compatibilizer to form a polar rubber ( It is believed that the compatibility between C) and the olefinic polymer (D) is improved. This thermoplastic elastomer composition preferably contains a reaction product (I) of a carbodiimide group-containing compound (A) and an olefinic polymer (B) having a group that reacts with the carbodiimide group.

Here, the effect of improving the compatibility by the reaction product (I) becomes more remarkable when the reaction product (I) has a main chain similar to that of the olefin polymer (D). The main chain of the olefin-based polymer (B) having a group that reacts with the carbodiimide group, which is the main chain of (I), and the main chain structure of the olefin-based polymer (D) are similar to each other. more preferred.

For example, when the olefin-based polymer (D) described later is a propylene-based polymer, the polyolefin main chain is a propylene-based polymer such as a propylene homopolymer or a copolymer of propylene and other α-olefins. A polymer can be preferably selected and used.

The density of the polyolefin used for graft copolymerization, that is, the density of the polyolefin main chain before introduction of the groups that react with carbodiimide, is usually 0.8 to 1.2 g/cm ³ , preferably 0.90 to 1.1 g/cm 3 . ³ , more preferably 0.925 to 1.0 g/cm ³ .

The melt flow rate (MFR) of the polyolefin main chain at 190°C or 230°C and a load of 2.16 kg according to ASTM D1238 is usually 0.01 to 500 g/10 minutes, preferably 0.05 to 200 g/10 minutes, more preferably 0.1 to 100 g/10 minutes. If the density and MFR are in this range, the density and MFR of the graft copolymer after modification will be about the same, making it easier to handle.

The crystallinity of the polyolefin main chain is usually 2% or more, preferably 5% or more, more preferably 10% or more. If the degree of crystallinity is within this range, the graft copolymer after modification is excellent in handleability.

The number average molecular weight (Mn) measured by gel permeation chromatography (GPC) of the polyolefin main chain used for graft copolymerization is preferably 5,000 to 500,000, more preferably 10,000 to 100,000. . If the average molecular weight (Mn) is within this range, the handleability is excellent. The number-average molecular weight of ethylene-based polyolefins can be obtained in terms of polyethylene if the comonomer content is 10 mol% or less, and in terms of ethylene-propylene if the comonomer content is 10 mol% or more (based on an ethylene content of 70 mol%). It is possible.

The polyolefin main chain as described above can be produced by any conventionally known method, for example, polymerization using a titanium-based catalyst, a vanadium-based catalyst, a metallocene catalyst, or the like. Moreover, the polyolefin used for graft modification may be in the form of either a resin or an elastomer, and may have both an isotactic structure and a syndiotactic structure, and there is no particular restriction on stereoregularity. It is also possible to use a commercially available resin as it is.

In the present invention, the unmodified polyolefin that serves as the polyolefin main chain may have properties similar to those of the olefin polymer (D) described below, or may be of a completely different type, but have a high degree of compatibility. is required, it is preferable that the density, monomer configuration, stereoregularity, structural unit arrangement such as random/block, etc. have properties similar to those of the olefin polymer (D), and in particular, the monomer configuration is similar. preferably. Further, the unmodified polyolefin that forms the polyolefin main chain is more preferably a thermoplastic polyolefin resin.

<Compound (b) having a group that reacts with a carbodiimide group>
Examples of the compound (b) having a group reactive with a carbodiimide group include compounds having a group having an active hydrogen reactive with a carbodiimide group, specifically carboxylic acid, carboxylic anhydride, amine, Examples include compounds having groups derived from alcohols, thiols, and the like. That is, in the present invention, the olefin polymer (B) having a group that reacts with a carbodiimide group includes, for example, a carboxylic anhydride group, a carboxy group (--COOH), and a hydroxy group (--OH) as the group that reacts with the carbodiimide group. , a thiol group (--SH) is preferably used.

As the compound (b) having a group that reacts with a carbodiimide group, among the above, a compound having a group derived from an unsaturated carboxylic acid such as carboxylic acid or carboxylic anhydride is preferably used. / or a derivative thereof is preferably used. In addition to compounds having a group having an active hydrogen, compounds having a group that can be easily converted to a group having an active hydrogen by water or the like can also be preferably used, specifically having an epoxy group or a glycidyl group. compound. In the present invention, the compound (b) having a group reactive with a carbodiimide group may be used singly or in combination of two or more.

When an unsaturated carboxylic acid and/or a derivative thereof is used as the compound (b) having a group that reacts with a carbodiimide group, the compound (b) includes an unsaturated compound having one or more carboxy groups and one or more carboxylic anhydride groups. Examples of unsaturated groups include vinyl groups, vinylene groups, and unsaturated cyclic hydrocarbon groups. Specific compounds (b) include acrylic acid, methacrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, norbornenedicarboxylic acid, bicyclo[2,2,1] Unsaturated carboxylic acids such as hept-2-ene-5,6-dicarboxylic acid, acid anhydrides thereof, or derivatives thereof (eg, acid halides, amides, imides, esters, etc.) can be mentioned. Specific examples of acid anhydrides or derivatives include malenyl chloride, malenylimide, maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo[2,2,1]hept-2-ene- 5,6-dicarboxylic anhydride, dimethyl maleate, monomethyl maleate, diethyl maleate, diethyl fumarate, dimethyl itaconate, diethyl citraconate, dimethyl tetrahydrophthalate, bicyclo[2,2,1]hept-2- Examples include dimethyl ene-5,6-dicarboxylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, glycidyl (meth)acrylate, aminoethyl methacrylate and aminopropyl methacrylate.

When using an unsaturated carboxylic acid and/or a derivative thereof as the compound (b) having a group that reacts with a carbodiimide group, one type can be used alone, or two or more types can be used in combination. can. Among these are maleic anhydride, (meth)acrylic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylic anhydride , hydroxyethyl (meth)acrylate, glycidyl methacrylate, aminopropyl methacrylate are preferred. Furthermore, dicarboxylic acid anhydrides such as maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, and bicyclo[2,2,1]hept-2-ene-5,6-dicarboxylic anhydride. is particularly preferred.

<Graft copolymerization method>
A method for obtaining the olefinic polymer (B) having a group reactive with a carbodiimide group, which is used in the present invention, by graft copolymerization (graft modification) includes, for example, the above polyolefin serving as the main chain (polyolefin main chain) (2) includes a method of graft copolymerizing a compound (b) having a group reactive with a carbodiimide group in the presence of a radical initiator. Such graft copolymerization may be carried out in the presence of other ethylenically unsaturated monomers, if necessary, together with the compound (b).

The method for graft-copolymerizing the compound (b) having a group that reacts with the carbodiimide group onto the polyolefin main chain is not particularly limited, and conventionally known graft polymerization methods such as a solution method and a melt-kneading method can be employed.

(radical copolymerization)
In the case of radical copolymerization, as the olefin, it is possible to employ the same olefin as in the case of forming the above-described polyolefin main chain. , the same as those described above in the section of graft copolymerization can be employed.

The method for copolymerizing the olefin and the compound (b) having a group reactive with a carbodiimide group is not particularly limited, and conventionally known radical copolymerization methods can be employed.

(Properties of the olefin polymer (B) having a group that reacts with the carbodiimide group)
The olefinic polymer (B) having a group that reacts with the carbodiimide group used in the present invention is generally at least partially It reacts with the group-containing compound (A) to form the reaction product (I). The thermoplastic elastomer composition exhibits a form in which each constituent component is highly dispersed and has excellent mechanical properties because the reaction product (I) acts as a compatibilizer in the thermoplastic elastomer composition. It is thought that one of the reasons is that it exhibits an effect.

The content of the compound (b) having a group reactive with the carbodiimide group (the content of the portion derived from the compound (b)) in the olefin polymer (B) having a group reactive with the carbodiimide group is usually 0. .1 to 10% by mass, preferably 0.1 to 3.0% by mass, more preferably 0.1 to 2.0% by mass. It is preferable that the content of the compound (b) is within the above range because the reaction with the carbodiimide group-containing compound (A) is likely to occur.

Further, in the present invention, when the content of the compound (b) having a group reactive with a carbodiimide group in the olefin polymer (B) having a group reactive with a carbodiimide group is within the above range, the carbodiimide group-containing compound Acts as a compatibilizer in the resulting thermoplastic elastomer composition by forming a reaction product (I) between (A) and an olefinic polymer (B) having a group that reacts with a carbodiimide group. is preferred because it indicates

In order to prevent gelation due to cross-linking, the lower the number average molecular weight of the olefin polymer (B) having a group that reacts with the carbodiimide group, It is preferable that the molar ratio of (the number of moles)/(the number of moles of the olefinic polymer (B) having a group reactive with the carbodiimide group) is small. That is, when the compound (b) is present in a state close to singular rather than plural on the main chain of the olefin polymer (B) having a group that reacts with the carbodiimide group, the carbodiimide group-containing It means that the carbodiimide group (N=C=N) of the compound (A) hardly causes gelation due to cross-linking when reacting with the compound (b) part.

In the present invention, by controlling the number average molecular weight (Mn) of the olefin polymer (B) having a group that reacts with the carbodiimide group and the content of the compound (b) having a group that reacts with the carbodiimide group, Even when the reaction product (I) is formed with the carbodiimide group-containing compound (A) during the production of the thermoplastic elastomer composition, gelation due to cross-linking is unlikely to occur, production stability can be maintained, and production stability can be maintained. In the thermoplastic elastomer composition obtained, the reaction product (I) can sufficiently exhibit performance as a compatibilizer.

In the present invention, the olefinic polymer (B) having a group reactive with a carbodiimide group preferably satisfies the following formula (1).
0.1<Mn/[(100−M)*f/M]<6 (1)
(In formula (1),
f: Formula weight (g/mol) of compound (b) having a group that reacts with a carbodiimide group
M: Content of compound (b) having a group that reacts with a carbodiimide group (content of portion derived from compound (b)) (% by mass)
Mn: Number average molecular weight of the olefinic polymer (B) having groups reactive with carbodiimide groups. )

In addition, from the viewpoint of manufacturing stability that does not cause gelation due to cross-linking, the range that satisfies the following formula (2) is more preferable, and the range that satisfies formula (3) is most preferable.
0.3<Mn/[(100−M)*f/M]<4 (2)
0.5<Mn/[(100−M)*f/M]<2.8 (3)

When the relationship between the number average molecular weight (Mn) of the olefin polymer (B) having a group reactive with a carbodiimide group and the compound (b) having a group reactive with a carbodiimide group is within the above range, the carbodiimide group-containing compound (A ) and an olefinic polymer (B) having a group reactive with a carbodiimide group, or when producing a thermoplastic elastomer composition, the carbodiimide group-containing compound (A) It is possible to suppress gelation due to cross-linking and stably produce.

In the present invention, when the olefin-based polymer (B) having a group reactive with a carbodiimide group is obtained by graft polymerization, the polyolefin to be the main chain for grafting has an ethylene content such as linear low-density polyethylene. A resin with a large amount of α-olefin tends to be crosslinked more easily than a resin with a large amount of α-olefin copolymerization such as an ethylene-butene copolymer. Therefore, when a resin having a high ethylene content is used as the main chain for grafting, the compound (b) having a group that reacts with a carbodiimide group is present in a number close to a single number on the molecular chain of the polyolefin. Gelation due to cross-linking can be suppressed as the numerical value of the formula is lower.

The number average molecular weight can be determined by general molecular weight measurement methods for polymers such as the GPC method, the light scattering method, the low angle light scattering photometry method, the vapor pressure osmotic pressure method, and the membrane osmotic pressure method.

The melt flow rate (MFR) at 190°C or 230°C under a load of 2.16 kg according to ASTM D1238 of the olefinic polymer (B) having a group that reacts with a carbodiimide group is the same as the polar rubber (C ) and the properties of the olefinic polymer (D), it is generally 0.01 to 500 g/10 minutes, preferably 0.05 to 300 g/10 minutes. If it is in the above range, the compatibility between the polar rubber (C) and the olefinic polymer (D) in the resulting thermoplastic elastomer composition will be more excellent, which is preferable.

The density of the olefin polymer (B) having a group that reacts with a carbodiimide group is usually 0.8 to 1.2 g/cm ³ , preferably 0.8 to 1.1 g/cm ³ , more preferably 0.8. ˜1.0 g/cm ³ .

Among the olefinic polymers (B) having a group reactive with a carbodiimide group within such a range, polyethylene, polypropylene, polybutene 1, poly-4-methylpentene-1 and copolymers of these with α-olefins Maleic anhydride graft copolymers of crystalline polyolefins such as coalescence are preferred, and depending on the object of compatibilization, maleic anhydride graft copolymers of polyethylene or polypropylene are more preferred, and maleic anhydride graft copolymers of polypropylene are preferred. Coalescing is even more preferred.

The density of the olefin polymer (B) having a group that reacts with the carbodiimide group is not particularly limited. A density close to that of the rubber (C) or a density between the density of the polar rubber (C) and the density of the olefinic polymer (D) is more preferable.

The olefin polymer (B) having a group that reacts with such a carbodiimide group may be appropriately prepared by the above-described graft copolymerization or radical copolymerization, or may be commercially available. . Examples of commercially available polyolefins having groups that react with carbodiimide groups include Admer (registered trademark) manufactured by Mitsui Chemicals, Inc., Orevac (registered trademark) manufactured by Arkema, and Polybond (registered trademark) manufactured by Addivant.

[Polar rubber (C)]
As the polar rubber (C), rubbers having polarity can be used without particular limitation. In addition to carbon (C) and hydrogen (H), nitrogen (N) and oxygen (O) , sulfur (S), halogen (F, Cl, Br, etc.), phosphorus (P) and other atoms are preferred, and rubbers having polar groups in side chains are more preferred. The polar rubber (C) has excellent properties such as oil resistance against non-polar oils.

Specific examples of the polar rubber (C) include a carboxy group-containing nitrile rubber, a hydrogenated carboxy group-containing nitrile rubber, a nitrile rubber, a hydrogenated nitrile rubber, a carboxy group-containing acrylic rubber, and an epoxy group-containing rubber. acrylic rubber, acrylic rubber, carboxy group-containing epichlorohydrin rubber, epichlorohydrin rubber, chloroprene rubber, chlorosulfonated polyethylene, chlorinated polyethylene, polysulfide rubber, fluororubber, hydrogenated ethylenically unsaturated nitrile-conjugated diene rubber, and the like. Various rubbers commercially available as polar rubbers can also be used in the present invention. Among these, nitrile rubbers and carboxyl group-containing nitrile rubbers are particularly preferred in terms of properties such as oil resistance to non-polar oils such as gasoline and lubricating oils.

The polar rubber (C) preferably has a number average molecular weight in the range of 5,000 to 2,000,000, more preferably in the range of 10,000 to 500,000. Although it depends on the use of the rubber composition, when the number average molecular weight is at least the above lower limit, desired rubber strength physical properties can be easily obtained, and when it is at most the above upper limit, desired moldability can be obtained. preferred because it is easy.

The Mooney viscosity (ML ₁₊₄ , 100° C.) of the polar rubber (C) is preferably 10-200, more preferably 20-150. When the Mooney viscosity is at least the lower limit, desired rubber strength physical properties are easily obtained, and when it is at most the upper limit, the handleability in an uncrosslinked state is good, and desired processability and moldability are obtained. preferred because it is easy.

The polar rubber (C) has a solubility parameter (SP value) of usually 16.5-30 (MPa) ^0.5 , preferably 17-29 (MPa) ^0.5 , more preferably 17.5-28 (MPa) ^0.5 . When the SP value is relatively high like this, the resistance to non-polar oils such as gasoline and lubricating oils is improved.

The polar rubber (C) may be used alone or in combination of two or more.

Although the polar rubber (C) used in the present invention is not particularly limited, it is preferably an amorphous elastic copolymer, at least a part of which can be crosslinked using a crosslinking agent.

(Polar rubber (C1) having a group that reacts with a carbodiimide group)
In the thermoplastic elastomer composition produced according to the present invention, the polar rubber (C) also preferably contains a polar rubber (C1) having a group that reacts with the carbodiimide group. In the present invention, the entire amount of the polar rubber (C) may be the polar rubber (C1) having a group that reacts with the carbodiimide group, or part of the polar rubber (C) has a group that reacts with the carbodiimide group. It may be a polar rubber (C1). As mentioned above, the "group reactive with a carbodiimide group" includes, for example, a group having an active hydrogen or a group that can be easily converted to a group having an active hydrogen with water or the like.

The polar rubber (C1) having a group that reacts with a carbodiimide group includes, for example, a carboxylic anhydride group, a carboxyl group (--COOH), a hydroxy group (--OH), a thiol group (--SH) that reacts with a carbodiimide group. Examples include polar rubbers having a group in a side chain or the like, particularly polar rubbers containing a carboxy group.

Preferably, the polar rubber (C1) includes a carboxy group-containing nitrile rubber, a hydrogenated carboxy group-containing nitrile rubber, a carboxy group-containing acrylic rubber, an epoxy group-containing acrylic rubber, a carboxy group-containing epichlorohydrin rubber, and the like.

The polar rubber (C1) having a group that reacts with a carbodiimide group may be used singly or in combination of two or more.

When the polar rubber (C) constituting the thermoplastic elastomer composition produced by the present invention contains a polar rubber (C1) having a group that reacts with a carbodiimide group, the order of melt-kneading, etc., also depends on the production process. However, the resulting thermoplastic elastomer composition contains the reaction product (II) between the carbodiimide group-containing compound (A) and the polar rubber (C1) having a group that reacts with the carbodiimide group. When the thermoplastic elastomer composition contains the reaction product (II), the compatibility of each component in the thermoplastic elastomer composition is further improved, which is preferable.

[Olefin polymer (D)]
The olefinic polymer (D) constituting the thermoplastic elastomer composition produced by the present invention is a polymer or copolymer mainly having structural units derived from olefins and having groups reactive with carbodiimide groups. have substantially no “Substantially free of” groups reactive with carbodiimide groups means that the thermoplastic elastomer composition of the present invention is prepared as a carbodiimide group-containing compound (A) and actually reacts with the carbodiimide groups. or, even if the group is contained in an extremely small amount, it means that it does not contribute to the action and effect of the present invention.

Examples of the olefinic polymer (D) are the same as those described in the section on the polyolefinic main chain, which is the main chain of the olefinic polymer (B) having a group that reacts with the carbodiimide group. . That is, the olefin polymer (D) used in the present invention is a polymer or copolymer mainly composed of an aliphatic α-olefin having 2 to 20 carbon atoms, a cyclic olefin, or a non-conjugated diene, preferably It is a polymer or copolymer mainly composed of an α-olefin having 2 to 10 carbon atoms, more preferably an α-olefin having 2 to 8 carbon atoms. These olefins as monomers may be used singly or in combination of two or more. The comonomer content is usually 50 mol % or less, preferably 40 mol % or less, more preferably 30 mol % or less.

In the present invention, the olefinic polymer (D) is usually a thermoplastic polyolefin resin.

In the present invention, the olefin polymer (D) is ethylene, propylene, 1-butene, 4-methyl-1-pentene, 3-methyl-1-butene, 1-hexene, 1-octene, tetracyclododecene. , norbornene homopolymers or copolymers can be preferably used. In addition, they can be used in both isotactic and syndiotactic structures, and stereoregularity is not particularly limited. Polyolefins such as those described above can be produced by any conventionally known method, and can be polymerized using, for example, titanium-based catalysts, vanadium-based catalysts, metallocene catalysts, and the like.

In the present invention, the olefin-based polymer (D) is preferably a polypropylene-based polymer, and examples of the polypropylene-based polymer include homopolymers of propylene, copolymers of propylene and other α-olefins, and the like. can be preferably selected and used. When the olefin polymer (D) is a polypropylene polymer, the melt flow rate (MFR) measured at 2.16 kgf and 230° C. according to ASTM D1238 is 0.01 to 500 g/10 min, preferably 0. 0.05 to 200 g/10 min, more preferably 0.1 to 100 g/10 min.

[Crosslinking agent (E)]
The cross-linking agent (E) used in the present invention is a cross-linking agent capable of cross-linking the polar rubber (C) described above. As the cross-linking agent (E), various known cross-linking agents generally used for cross-linking rubber can be used. Specifically, for example, organic peroxides, phenolic resins, sulfur-based compounds, hydrosilicone-based compounds, amino resins, quinones or derivatives thereof, amine-based compounds, azo-based compounds, epoxy-based compounds, thiourea-based compounds, thiazole-based cross-linking agents such as compounds, triazine-based compounds, and isocyanates. Among these, cross-linking agents such as organic peroxides, phenolic resins and sulfur compounds are preferable.

Organic peroxides include dicumyl peroxide, di-tert-butyl peroxide, 2,5-di-(tert-butylperoxy)hexane, 2,5-dimethyl-2,5-di-(tert-butylperoxy) Hexane, 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexyne-3, 1,3-bis(tert-butylperoxyisopropyl)benzene, 1,1-bis(tert-butylperoxy)- 3,3,5-trimethylcyclohexane, n-butyl-4,4-bis(tert-butylperoxy)valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butyl peroxybenzoate, tert -butylperoxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide, tert-butyl cumyl peroxide and the like.

Among these, 2,5-di-(tert-butylperoxy)hexane, 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexane, 2,5-dimethyl-2,5-di- (tert-butylperoxy)hexyne-3, 1,3-bis(tert-butylperoxyisopropyl)benzene, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, n-butyl-4 Bifunctional organic peroxides such as ,4-bis(tert-butylperoxy)valerate are preferred, and among them, 2,5-di-(tert-butylperoxy)hexane, 2,5-dimethyl-2,5- Most preferred are di-(tert-butylperoxy)hexane, 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexyne-3.

When an organic peroxide is used as the cross-linking agent (E), it is preferable to use a cross-linking aid together. Such cross-linking aids include, for example, sulfur, quinonedioxime cross-linking aids such as p-quinonedioxime; acrylic cross-linking aids such as ethylene glycol dimethacrylate and trimethylolpropane trimethacrylate; diallyl phthalate, triallyl allyl-based cross-linking aids such as isocyanurate; other maleimide-based cross-linking aids; divinylbenzene; zinc oxide (for example, ZnO #1, zinc oxide type 2, manufactured by Hakusui Tech Co., Ltd.), metal oxides such as magnesium oxide, and the like. be done. The amount of the cross-linking aid compounded is generally 0.01 to 10 mol, preferably 0.1 to 7 mol, more preferably 0.5 to 5 mol, per 1 mol of the organic peroxide.

Examples of phenol resin-based cross-linking agents include resol resins obtained by condensing alkyl-substituted or unsubstituted phenol with aldehyde (preferably formaldehyde) in the presence of an alkali catalyst. The alkyl group of the alkyl-substituted phenol is preferably an alkyl group of 1 to about 10 carbon atoms. Further preferred are dimethylolphenols or phenolic resins substituted with alkyl groups having from 1 to about 10 carbon atoms in the p-position. Cross-linking with a phenolic resin-based cross-linking agent is described, for example, in US Pat. No. 4,311,628, US Pat. No. 2,972,600, and US Pat.

Phenolic resin-based cross-linking agents are also commercially available. Commercially available products thereof include, for example, Tackyroll 201, Tackyroll 250-I, and Tackyroll 250-III available from Taoka Kagaku Kogyo Co., Ltd.; SP1045, SP1055, and SP1056 available from SI Group; Shownol CRM available from Showa Denko K.K.; Sumilite Resin PR from Sumitomo Bakelite Co., Ltd.; Resitop from Gun Ei Chemical Industry Co., Ltd. (all trade names). These can also be used in combination of two or more. Among them, Takkiroru 250-III (brominated alkylphenol formaldehyde resin) manufactured by Taoka Chemical Co., Ltd. and SP1055 (brominated alkylphenol formaldehyde resin) manufactured by SI Group are preferable.

Moreover, when using a phenolic resin-type crosslinking agent as a crosslinking agent (E), it is preferable to use a crosslinking aid together. Such cross-linking aids include, for example, metal halides such as stannous chloride and ferric chloride; halogen-containing polymers such as chloroprene rubber and halogenated butyl rubber; (manufactured by Hakusui Tech Co., Ltd.), and metal oxides such as magnesium oxide.

Sulfur compounds (vulcanizing agents) include sulfur, sulfur chloride, sulfur dichloride, morpholine disulfide, alkylphenol disulfide, tetramethylthiuram disulfide, selenium dithiocarbamate and the like.

When using a sulfur compound as the cross-linking agent (E), it is preferable to use a vulcanization accelerator together. Examples of such vulcanization accelerators include N-cyclohexyl-2-benzothiazolesulfenamide, N-oxydiethylene-2-benzothiazolesulfenamide, N,N'-diisopropyl-2-benzothiazolesulfenamide, 2-mercaptobenzothiazole (for example, Suncellar M (trade name; manufactured by Sanshin Chemical Industry Co., Ltd.)), 2-(4-morpholinodithio) benzothiazole (for example, Noxcellar MDB-P (trade name; Ouchi Shinko Kagaku Kogyo Co., Ltd.)), 2-(2,4-dinitrophenyl)mercaptobenzothiazole, 2-(2,6-diethyl-4-morpholinothio)benzothiazole and dibenzothiazyl disulfide (for example, Suncellar DM (product Sanshin Chemical Industry Co., Ltd.)) and other thiazole-based vulcanization accelerators; guanidine-based vulcanization accelerators such as diphenylguanidine, triphenylguanidine and diorthotolylguanidine; aldehydeamine vulcanization accelerators such as condensates; imidazoline vulcanization accelerators such as 2-mercaptoimidazoline; thiourea vulcanization accelerators such as diethylthiourea and dibutylthiourea; Sanshin Chemical Industry Co., Ltd.)), tetramethylthiuram disulfide (for example, Suncella TT (product name; Sanshin Chemical Industry Co., Ltd.)), tetraethylthiuram disulfide (for example, Suncella TET (product name; Sanshin Kagaku Kogyo Co., Ltd.)), tetrabutyl thiuram disulfide (for example, Suncellar TBT (trade name; manufactured by Sanshin Chemical Industry Co., Ltd.)) and dipentamethylene thiuram tetrasulfide (for example, Suncellar TRA (trade name; Sanshin Chemical Industry Co., Ltd.) Co., Ltd.)) and other thiuram-based vulcanization accelerators; )) and dithioate-based vulcanization accelerators such as tellurium diethyldithiocarbamate; Co., Ltd.)) and thiourea-based vulcanization accelerators such as N,N'-diethylthiourea; Xanthate-based vulcanization accelerators such as zinc luxatogenate; and zinc white (for example, META-Z102 (trade name; manufactured by Inoue Lime Industry Co., Ltd., zinc oxide)).

Moreover, when using a sulfur compound as a crosslinking agent (E), it is also preferable to use a vulcanization aid. Examples of vulcanizing aids include zinc oxide (for example, ZnO #1, zinc oxide type 2, manufactured by Hakusui Tech Co., Ltd.), magnesium oxide, and the like.

Among these cross-linking agents, organic peroxide cross-linking agents and phenolic resin cross-linking agents are preferably used as the cross-linking agent (E) in the thermoplastic elastomer composition of the present invention produced according to the present invention.

The thermoplastic elastomer composition produced by the present invention contains the above-mentioned polar rubber (C) and a cross-linking agent (E) capable of cross-linking the polar rubber (C) as raw materials, so that the raw materials are dynamically Heat treated. In the thermoplastic elastomer composition, usually at least part of the polar rubber (C) forms a crosslinked structure. That is, this thermoplastic elastomer composition usually contains a crosslinked product of the polar rubber (C). Since this thermoplastic elastomer composition contains a crosslinked polar rubber which is a crosslinked product of polar rubber, it has suitable elasticity and excellent chemical resistance.

Further, in the thermoplastic elastomer composition produced by the present invention, the polar rubber (C), the reaction product (II), or the carbodiimide group-containing compound (A) and an olefinic compound having a group that reacts with the carbodiimide group Any one of the three-component reaction products (III) of the polymer (B) and the polar rubber (C) may form crosslinks, or the reaction product (II) or the reaction product (III) and the polar rubber (C) may be mutually crosslinked. In this thermoplastic elastomer composition, when two or more components have mutual cross-linking, each component of the thermoplastic elastomer composition becomes more excellent in compatibility and separation is less likely to occur, which is preferable.

[Other ingredients]
The thermoplastic elastomer composition produced by the present invention comprises the carbodiimide group-containing compound (A) described above, the olefinic polymer (B) having a group reactive with the carbodiimide group, the polar rubber (C), and the olefinic polymer ( Components other than D) and the cross-linking agent (E) may be contained as raw materials within a range that does not impair the object of the present invention.

That is, the thermoplastic elastomer composition produced by the present invention can be blended with other resins, elastomers, and the like within limits not impairing the object of the present invention. In addition, the thermoplastic elastomer composition contains a known plasticizer (F) and cross-linking aid (G), as well as a plasticizer, softener, tackifier, anti-aging agent, as long as the objects of the present invention are not impaired. agent, processing aid, adhesion imparting agent, inorganic filler, inorganic fiber such as glass fiber, acrylic fiber, PET fiber, PEN fiber, kenaf, organic fiber such as vegetable fiber, organic filler, heat stabilizer, weather stabilizer , antistatic agents, colorants, lubricants, flame retardants, anti-blooming agents, reinforcing agents, activators, hygroscopic agents, colorants, and thickeners (H).

Among these, the thermoplastic elastomer composition produced according to the present invention preferably contains a plasticizer (F) and/or a cross-linking aid (G). The plasticizer (F) is not particularly limited, and known plasticizers can be used. For example, phthalate plasticizers such as dibutyl phthalate and dioctyl phthalate; Aliphatic dibasic acid ester plasticizer; Trimellitate ester plasticizer such as tridecyl trimellitate; Aliphatic dibasic acid ether ester plasticizer such as dibutoxyethoxyethyl adipate; Ether ester plasticizer; Polyester Phosphate plasticizers; Epoxy plasticizers such as epoxidized soybean oil and epoxidized linseed oil; Petroleum oils such as process oil, lubricating oil, aromatic oil, naphthenic oil, paraffin oil, liquid paraffin, and petrolatum Coal tar such as coal tar and coal tar pitch; Fatty oils such as castor oil, linseed oil, rapeseed oil, soybean oil and coconut oil; Waxes such as tall oil, beeswax and lanolin; Ricinoleic acid, palmitin Acids, stearic acid, fatty acids such as calcium stearate, or metal salts thereof; petroleum resins, chromanindene resins, synthetic polymer substances such as atactic polypropylene; other microchlorine waxes, sub (factice), liquid polybutadiene, modified liquid polybutadiene, liquid thiocol and the like, among them various ester plasticizers such as phthalate plasticizers, aliphatic dibasic acid ether ester plasticizers, and ether ester plasticizers from the viewpoint of affinity with the polar rubber (C) Plasticizers are preferred. The cross-linking aid (G) is not particularly limited, but includes the cross-linking aids described above in the section of the cross-linking agent (E).

These other components may be blended from the beginning as raw materials during the production of the thermoplastic elastomer composition, or may be added at the stage of dynamically heat-treating the raw materials. It may be added after it is obtained.

[Blending ratio of each component]
The thermoplastic elastomer composition produced by the present invention is not particularly limited, but includes an olefinic polymer (B) having a group that reacts with a carbodiimide group, a polar rubber (C), and an olefinic polymer ( The carbodiimide group-containing compound (A) is usually added in an amount of 0.01 to 30 parts by mass, preferably 0.01 to 20 parts by mass, and more preferably 0.01 to 15 parts by mass based on the total 100 parts by mass of D). It is desirable that it is obtained using a range.

Further, the thermoplastic elastomer composition produced by the present invention comprises a carbodiimide group-containing compound (A), an olefinic polymer (B) having a group reactive with the carbodiimide group, the polar rubber (C), and the olefinic In a total of 100% by mass of the polymer (D), the carbodiimide group-containing compound (A) is usually 0.01 to 30% by mass, preferably 0.01 to 20% by mass, and reacts with the carbodiimide group. The olefinic polymer (B) having a group is usually 0.05 to 70% by mass, preferably 0.1 to 60% by mass, and the polar rubber (C) is usually 10 to 95% by mass, preferably 20 to 20% by mass. In a preferred embodiment, the olefinic polymer (D) is used in a proportion of 90% by mass, preferably in a proportion of 2 to 85% by mass, more preferably in a proportion of 4 to 70% by mass, as a raw material.

Furthermore, the thermoplastic elastomer composition produced by the present invention contains carbodiimide groups with respect to a total of 100 parts by mass of the olefin polymer (B) having a group that reacts with the carbodiimide group and the olefin polymer (D). Compound (A) is preferably added in an amount of usually 0.01 to 30 parts by mass, preferably 0.03 to 25 parts by mass.

Further, the thermoplastic elastomer composition has a mass ratio (C) of the total of the polar rubber (C), the olefinic polymer (B) having a group that reacts with the carbodiimide group, and the olefinic polymer (D): [( B)+(D)] usually satisfies 1:99 to 99:1, preferably 5:95 to 95:5.

In the thermoplastic elastomer composition produced by the present invention, the compounding ratio of the polar rubber (C) and the olefinic polymer (D) is not particularly limited, but the mass ratio of the raw materials (C ):(D) is generally in a ratio of 1:99 to 99:1, preferably 5:95 to 95:5. This thermoplastic elastomer composition comprises, for example, a polar rubber (C) and an olefinic polymer (D) in a ratio satisfying a mass ratio (C):(D) of 51:49 to 99:1. It may be contained, or may be contained in a ratio that satisfies 30:70 to 70:30.

In the thermoplastic elastomer composition produced by the present invention, depending on the types of the polar rubber (C) and the crosslinking agent (E), the crosslinking agent (E) is added to 100 parts by mass of the polar rubber (C) is usually 0.01 to 15 parts by mass, preferably 0.05 to 10 parts by mass.

Furthermore, when the thermoplastic elastomer composition produced according to the present invention contains a plasticizer (F), the plasticizer (F) is usually added in an amount of 1 to 150 parts by mass based on 100 parts by mass of the polar rubber (C). It is desirable to contain 3 to 100 parts by mass.

[Thermoplastic elastomer composition]
The thermoplastic elastomer composition produced by the present invention comprises the carbodiimide group-containing compound (A) described above, the olefinic polymer (B) having a group reactive with the carbodiimide group, the polar rubber (C), and the olefinic polymer ( D) and a cross-linking agent (E) capable of cross-linking the polar rubber (C) are dynamically heat-treated. This thermoplastic elastomer composition may contain other components as described above, if desired. The blending ratio of each component in this thermoplastic elastomer composition is not particularly limited, and is preferably as described above.

Since the thermoplastic elastomer composition produced by the present invention contains, as raw materials, a carbodiimide group-containing compound (A) and a compound (B) containing a group that reacts with the carbodiimide group, the resulting thermoplastic composition contains In, the carbodiimide group-containing compound (A) described above and the "group that reacts with the carbodiimide group" of the olefin polymer (B) that has a group that reacts with the carbodiimide group are at least partially reacted by melt-kneading. , the carbodiimide group-containing compound (A) and the olefinic polymer (B) having a group reactive with the carbodiimide group may form a reaction product (I). This reaction product (I) has a polyolefin chain derived from the olefinic polymer (B) having a group that reacts with a carbodiimide group, and also has a carbodiimide group. Since such a reaction product (I) has a carbodiimide group which is a polar group, it has excellent compatibility with the polar rubber (C), and since it has a polyolefin chain, it can be used with the olefin polymer (D). It is also excellent in compatibility with. Therefore, in this thermoplastic elastomer composition, the polar rubber (C) and the olefinic polymer (D) are highly mixed and well dispersed as compared with the case where the two are simply mixed. state. Therefore, the thermoplastic elastomer composition preferably contains the reaction product (I) of the carbodiimide group-containing compound (A) and the olefinic polymer (B) having a group reactive with the carbodiimide group.

Further, since the thermoplastic elastomer composition produced by the present invention contains the polar rubber (C) and the cross-linking agent (E) capable of cross-linking the polar rubber (C) as raw materials, the thermoplastic elastomer composition At least part of the polar rubber (C) is crosslinked in the product. That is, this thermoplastic elastomer composition usually contains a crosslinked polar rubber which is a crosslinked product of the polar rubber (C). In this thermoplastic elastomer composition, the crosslinked polar rubber, which is a crosslinked product of the polar rubber (C), and the olefinic polymer (D) are highly dispersed.

Furthermore, in the thermoplastic elastomer composition produced by the present invention, any of the polar rubber (C), the reaction product (II), or the reaction product (III) may form crosslinks, Further, the reaction product (II) or reaction product (III) and the polar rubber (C) may have mutual cross-linking. That is, the thermoplastic elastomer composition may contain a crosslinked product in which two or more of these components are mutually crosslinked.

Such a thermoplastic elastomer composition has suitable elasticity and excellent chemical resistance due to the inclusion of the crosslinked product, and excellent moldability due to the inclusion of the olefinic polymer (D). have. In addition, this thermoplastic elastomer composition is preferable because each component constituting the composition is highly dispersed and separation is unlikely to occur. This is because the reaction product (I), the reaction product (II), etc. are generated in the thermoplastic elastomer composition portion and act as a compatibilizer, and at least a part of the raw materials form crosslinks. This is considered to be caused by mutual entanglement and the like.

In the thermoplastic elastomer composition produced by the present invention, the crosslinked polar rubber, which is a crosslinked product of the polar rubber (C), and the olefinic polymer (D) are highly dispersed, and the thermoplastic elastomer composition The article has excellent moldability, and the molded article obtained from the thermoplastic elastomer has excellent elasticity, as well as excellent abrasion resistance and oil resistance. In this thermoplastic elastomer composition, each component, particularly the crosslinked polar rubber and the olefinic polymer (D), are highly dispersed. By observing the surface or cross section with a microscope or the like, it can be easily confirmed that the dispersed particle diameter is sufficiently small.

In the thermoplastic elastomer composition produced by the present invention, a sea-island structure is observed in a scanning electron microscope (SEM) image at a magnification of 200 or more, for example, an image at a magnification of about 1000, and the average particle size of the island phase is preferably Desirably, the range is 0.01 to 20 μm, more preferably 0.01 to 10 μm.

Molded articles containing at least a portion of the thermoplastic elastomer composition produced by the present invention can be easily produced with good moldability, and have mechanical properties such as flexibility, elasticity, breaking strength, and resistance to compression set. excellent mechanical properties, oil resistance and chemical resistance. The molding method for producing the molded article is not particularly limited, and any conventionally known method can be adopted. For example, methods such as injection molding, press molding, and extrusion molding can be adopted. can be done.

Such a thermoplastic elastomer composition can be suitably used as a molding material in various fields in which elastic moldings have been conventionally used.

EXAMPLES The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples.

<Measurement/evaluation method>
In the following examples and comparative examples, each property was measured or evaluated as follows.

[Number average molecular weight (Mn)]
Number average molecular weight (Mn) was measured by gel permeation chromatography (GPC). Using a Gel Permeation Chromatograph Alliance GPC-2000 manufactured by Waters, the measurement was performed as follows. As the separation columns, two TSKgel GMH6-HT and two TSKgel GMH6-HTL were used, the column size was 7.5 mm in diameter and 300 mm in length, the column temperature was 140°C, and the mobile phase was o - Using dichlorobenzene (Wako Pure Chemical Industries) and 0.025% by mass of BHT (Takeda Pharmaceutical) as an antioxidant, moving at 1.0 ml/min, sample concentration was 15 mg/10 mL, and sample injection volume was 500 micrometers. liters and a differential refractometer was used as a detector. Standard polystyrene used was manufactured by Tosoh Corporation for molecular weights Mw<1000 and Mw>4×10 ⁶ , and pressure chemical for molecular weights of 1000≦Mw≦4×10 ⁶ . For maleic anhydride-modified polypropylene, it was calculated in terms of polypropylene.

[Activation energy ΔE (J/mol), frequency factor A (hr ⁻¹ )]
According to JIS K6300-2, the cross-linking curve was measured at multiple temperatures to calculate t'c(90) and obtain the cross-linking rate. Specifically, first, the cross-linking curve is measured at 180°C, and if the cross-linking at 180°C is fast, the cross-linking curve is measured at a lower temperature, and if the cross-linking is slow, the cross-linking curve is measured at a higher temperature. The cross-linking rate at each temperature was obtained. The measurement temperature was measured at intervals of about 5 to 10° C. at three or more points. The obtained numerical values were plotted by Arrhenius plotting according to a standard method to obtain an approximate straight line, and the activation energy ΔE (J/mol) was calculated from the slope of the straight line, and the frequency factor A (hr ⁻¹ ) was calculated from the intercept.

[Shore A hardness]
It was measured with a Shore hardness tester (A hardness tester) using a press sheet with a thickness of 2 mm according to JIS K6253.

[Compression set (CS)]
A press-molded sheet produced from a thermoplastic elastomer composition by a press-molding machine was compressed by 25% using a spacer according to JIS K6262, heat-treated at 70°C for 24 hours, and then placed in a thermostatic chamber at 23°C. After allowing to stand for 30 minutes, the thickness was measured, and the compression set (CS) was obtained from the following formula.
CS=[(t0−t1)/(t0−t2)]×100
CS: compression set rate (%)
t0: Original thickness of press-molded sheet (mm)
t1: Thickness (mm) of press-molded sheet after standing for 30 minutes
t2: Thickness (mm) of press-formed sheet under compression strain

[Strand formability]
The thermoplastic elastomer composition was introduced into a HYPER REX (manufactured by Kobe Steel, Ltd., with a die attached to the tip) set at 190° C. and extruded into a strand. At this time, the strands were stably extruded as "◯", the strands were frequently cut as "Δ", and the strands could not be extruded as "X".

[Production Example 1]
<Production of maleic anhydride-modified polypropylene (B-1)>
100 parts by mass of polypropylene (Prime Polypro (registered trademark) F327, manufactured by Prime Polymer Co., Ltd.), 1 part by mass of maleic anhydride (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 2,5-dimethyl-2,5-bis ( 0.25 parts by mass of tert-butylperoxy)hexyne-3 (manufactured by NOF Corporation, trade name Perhexyne (registered trademark) 25B) was mixed, and a twin-screw kneader (manufactured by Japan Steel Works, Ltd., TEX-30, L/D = 40, using a vacuum vent), extruded at a cylinder temperature of 220°C, a screw rotation speed of 200 rpm, and a discharge rate of 80 g/min to obtain a maleic anhydride-modified polypropylene (B-1). The obtained maleic anhydride-modified polypropylene (B-1) is dissolved in xylene, and then the obtained xylene solution is poured into acetone to reprecipitate and purify, and the graft amount of maleic anhydride is measured by IR. As a result, it was 0.7% by mass. Also, the number average molecular weight (Mn) was 28,000 when measured by GPC.

[Example 1]
Polycarbodiimide (A-1) which is a carbodiimide group-containing compound (manufactured by Nisshinbo Chemical Co., Ltd., Carbodilite (registered trademark) HMV-15CA, carbodiimide equivalent weight 262 g), maleic anhydride-modified polypropylene obtained in Production Example 1 (B-1) , Part of polypropylene (D-1) (homopolypropylene, manufactured by Prime Polymer Co., Ltd., Prime Polypro (registered trademark) F113G, MFR: 3.0 g/10 min) [4.22 parts by mass (D-1) ¹⁾ ] was introduced into an extruder (manufactured by The Japan Steel Works, Ltd., TEX44, L/D = 70) at a compounding amount (parts by mass) shown in Table 1, a cylinder temperature of 290 ° C., a screw rotation speed of 760 rpm, and a discharge amount of 1.33 kg. / min to obtain a composition containing a reaction product (contact product) of polycarbodiimide (A-1) and maleic anhydride-modified polypropylene (B-1) and polypropylene (D-1) (Second one-step formulation).

Next, the remainder of polypropylene (D-1) [23.00 parts by mass (D-1) ²⁾ ], nitrile rubber (C-1) which is a polar rubber (manufactured by Nippon Zeon Co., Ltd., Nipol (registered trademark) 1042, NBR, Mooney viscosity = 77.5, bound acrylonitrile amount = 33.5%, SP value = about 20 (MPa) ^0.5 ), polar rubber (C1-1) having a group that reacts with a carbodiimide group (manufactured by Nippon Zeon Co., Ltd. , Nipol (registered trademark) NX775, carboxyl group-containing NBR, Mooney viscosity = 44.0, bound acrylonitrile amount = 26.7%, SP value = about 20 (MPa) ^0.5 ), plasticizer (F-1) (Co., Ltd. Adekasizer (registered trademark) RS-107 manufactured by ADEKA), additive (H-1) (manufactured by BASF, Irganox (registered trademark) 1010, phenolic antioxidant) and the above composition are mixed with an intermeshing kneader. (BB-L3200IM, 3.6 liters, manufactured by Kobe Steel, Ltd.) was introduced so as to have a compounding amount (parts by mass) shown in Table 1, and melt-kneaded at 120 rpm (second stage compounding). After that, when the resin temperature T2 in the kneader reaches about 145 ° C., the cross-linking agent (E-1) (manufactured by NOF Corporation, Perhexa (registered trademark) 25B, organic peroxide cross-linking agent) and cross-linking aid ( G-1) (manufactured by NS Styrene Monomer Co., Ltd., divinylbenzene-based cross-linking aid, DVB-810) was put into an intermeshing kneader to obtain a Tmax. is about 210° C., Tave. Dynamic cross-linking was carried out while kneading so that the temperature was about 190° C. (third stage compounding) to obtain a thermoplastic elastomer composition. The amount of thermoplastic elastomer composition obtained was about 3 kg/batch.

The obtained thermoplastic elastomer composition was introduced into HYPER REX (manufactured by Kobe Steel, Ltd.) set at 190° C., and the strand formability was evaluated. Also, the obtained thermoplastic elastomer composition was press-molded at 210° C. to a thickness of 2 mm, punched into various test shapes, and used as samples, and the physical properties were measured by the above test methods. Table 1 shows the results.

[Example 2]
In Example 1, in addition to additive (H-1), additive (H-2) (manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd., Nocrac (registered trademark) 224) was used, and each component is shown in Table 1. A thermoplastic elastomer composition was obtained in the same manner as in Example 1, except that the amount (parts by mass) was changed. The resulting thermoplastic elastomer composition was approximately 3 kg/batch. Table 1 shows the results.

[Example 3]
In Example 1, the additive (H-2) was used in addition to the additive (H-1), and the kneader was an intermeshing kneader (BB-14IM, manufactured by Kobe Steel, Ltd., 14.4 liters ), and Tmax. is about 220° C., Tave. A thermoplastic elastomer composition was obtained in the same manner as in Example 1, except that the mixture was kneaded at a temperature of about 200°C. The resulting thermoplastic elastomer composition was approximately 12 kg/batch. Table 1 shows the results.

[Example 4]
In Example 3, Tmax. is about 250° C., Tave. A thermoplastic elastomer composition was obtained in the same manner as in Example 3, except that the mixture was kneaded at a temperature of about 215°C. The resulting thermoplastic elastomer composition was approximately 12 kg/batch. Table 1 shows the results.

[Example 5]
In Example 1, instead of the cross-linking agent (E-1), the cross-linking agent (E-2) (manufactured by NOF Corporation, Perhexin 25B, organic peroxide-based cross-linking agent) was added in the amount shown in Table 1 ( A thermoplastic elastomer composition was obtained in the same manner as in Example 1, except that the above was used in (parts by mass). The resulting thermoplastic elastomer composition was approximately 3 kg/batch. Table 1 shows the results.

[Example 6]
In Example 1, instead of the cross-linking agent (E-1) and cross-linking aid (G-1), cross-linking agent (E-3) (manufactured by SI Group, SP1055F, phenol-based cross-linking agent) and cross-linking aid ( G-2) (manufactured by Hakusui Tech Co., Ltd., zinc oxide type 2) was used in the amount (parts by mass) shown in Table 1, and Tmax. is about 250° C., Tave. A thermoplastic elastomer composition was obtained in the same manner as in Example 1, except that the mixture was kneaded at a temperature of about 210°C. The resulting thermoplastic elastomer composition was approximately 3 kg/batch. Table 1 shows the results.

[Example 7]
In Example 6, instead of polypropylene (D-1) ²⁾ , polypropylene (D-2) (made by Prime Polymer Co., Ltd., Prime Polypro (registered trademark) F227D, random PP) was used. A thermoplastic elastomer composition was obtained in the same manner as in Example 6. The resulting thermoplastic elastomer composition was approximately 3 kg/batch. Table 1 shows the results.

[Comparative Example 1]
In Example 7, Tmax. is about 180° C., Tave. A thermoplastic elastomer composition was obtained in the same manner as in Example 7, except that the mixture was kneaded at a temperature of about 175°C. The resulting thermoplastic elastomer composition was approximately 3 kg/batch. Table 2 shows the results.

[Comparative Example 2]
In Example 4, Tmax. A thermoplastic elastomer composition was obtained in the same manner as in Example 4, except that the mixture was kneaded so that the temperature was about 225°C and the T2 was about 205°C. The resulting thermoplastic elastomer composition was approximately 12 kg/batch. Table 2 shows the results.

[Comparative Example 3]
In Example 1, Tmax. is about 270° C., Tave. A thermoplastic elastomer composition was obtained in the same manner as in Example 1, except that the mixture was kneaded at a temperature of about 250°C. The resulting thermoplastic elastomer composition was approximately 3 kg/batch. Table 2 shows the results.

[Comparative Example 4]
A thermoplastic elastomer composition was obtained in the same manner as in Example 6, except that the cross-linking aid (G-2) was not used. The resulting thermoplastic elastomer composition was approximately 3 kg/batch. Table 2 shows the results.

The thermoplastic elastomer compositions obtained in Examples 1 to 7 were excellent in mechanical properties (A hardness, compression set) and moldability. On the other hand, the thermoplastic elastomer composition obtained in Comparative Example 1 did not satisfy the condition (1) (Tmax. (°C) was less than T1 (°C)), and thus was inferior in resistance to compression set. The thermoplastic elastomer composition obtained in Comparative Example 2 did not satisfy the condition (2) (T2 was higher than T3), and was inferior in moldability. Since the thermoplastic elastomer composition obtained in Comparative Example 3 did not satisfy the condition (3) (P1 was greater than 8.5), the deterioration of the resin progressed and the composition could not be molded into a strand. . Since the thermoplastic elastomer composition obtained in Comparative Example 4 did not satisfy the condition (3) (P1 was less than 2.0), it was insufficiently crosslinked and inferior in resistance to compression set.

By the production method of the present invention, a thermoplastic elastomer composition having elasticity, excellent oil resistance, chemical resistance, etc., and excellent moldability is produced. This thermoplastic elastomer composition can be suitably used as a material for moldings in various fields in which elastic moldings have conventionally been used. Specific examples include tire rubber, O-rings, industrial rolls, automobile boots (eg rack and pinion boots, constant velocity joint boots), packing (eg condenser packing), gaskets, belts (eg heat insulation belts, copier belts), hoses (e.g. water hoses, brake reservoir hoses, radiator hoses), anti-vibration rubbers, sponges (e.g. weather strip sponges, heat insulation sponges, protection sponges, fine foam sponges), cables (e.g. ignition cables) , cabtyre cables, high-tension cables), wire covering materials (e.g., high-voltage wire covering materials, low-voltage wire covering materials, marine wire covering materials), glass run channels, color skin materials, paper feed rolls, shoe soles, roofing sheets, etc. is mentioned.

Claims (11)

carbodiimide group-containing compound (A),
an olefin-based polymer (B) having a group that reacts with a carbodiimide group;
a polar rubber (C) having a solubility parameter (SP value) of 16.5 to 30 (MPa) ^0.5 ;
An olefin polymer (D) having no group reactive with a carbodiimide group , and a cross-linking agent (E) capable of cross-linking the polar rubber (C),
A method for producing a thermoplastic elastomer composition comprising a step of dynamically crosslinking using a batch type kneader under conditions satisfying the following conditions (1) to (3).
(1) Tmax. ≧T1
(“Tmax.” is the maximum resin temperature (° C.) from when the cross-linking agent (E) is introduced into the batch kneader until the thermoplastic elastomer composition is discharged from the batch kneader. ” is the temperature (° C.) defined by the following formula (i).)
T1=ΔE/(8.314×(LnA−3))−273.15 (i)
(“ΔE” is the activation energy (J/mol) calculated from the slope of the Arrhenius plot created from the cross-linking curves measured at multiple temperatures using the polar rubber (C) and the cross-linking agent (E). ” is the frequency factor (hr ⁻¹ ) calculated from the intercept.)
(2) T2 ≤ T3
(“T2” is the resin temperature (° C.) in the kneader when the cross-linking agent (E) is introduced into the batch type kneader, and “T3” is the temperature (° C.) defined by the following formula (ii). .)
T3=ΔE/(8.314×(LnA−5))−273.15 (ii)
(3) 2.0 ≤ P1 ≤ 8.5
("P1" is a value defined by the following formula (iii).)
P1=LnA−ΔE/(8.314×(Tave.+273.15)) (iii)
("Tave." is the average value (°C) of the resin temperature from the state in which the cross-linking agent (E) is present and the olefinic polymer (D) is molten to the completion of kneading and discharge.) 2. The composition according to claim 1, wherein the composition in the dynamic cross-linking step contains a reaction product (I) of a carbodiimide group-containing compound (A) and an olefinic polymer (B) having a group that reacts with a carbodiimide group. A method of making the described thermoplastic elastomer composition. 3. The method for producing a thermoplastic elastomer composition according to claim 1, wherein the polar rubber (C) comprises a polar rubber (C1) having a group that reacts with a carbodiimide group. 4. The method for producing a thermoplastic elastomer composition according to claim 3, wherein the polar rubber (C1) having a group that reacts with a carbodiimide group is a polar rubber having a group having an active hydrogen in its side chain. 5. The method for producing a thermoplastic elastomer composition according to claim 3, comprising a reaction product (II) of a carbodiimide group-containing compound (A) and a polar rubber (C1) having a group reactive with a carbodiimide group. 6. The method for producing a thermoplastic elastomer composition according to any one of claims 1 to 5, wherein the carbodiimide group-containing compound (A) is a polycarbodiimide having a repeating unit represented by the following general formula.
-N=C=N-R ¹ -
(In the formula, R ¹ represents a divalent organic group.) 7. The thermoplastic elastomer composition according to any one of claims 1 to 6, wherein the olefinic polymer (B) having a group reactive with a carbodiimide group is an olefinic polymer having a group having an active hydrogen in its side chain. manufacturing method. 8. Any one of claims 1 to 7, wherein the olefin polymer (B) having a group reactive with a carbodiimide group is a graft copolymer of a polyolefin and a compound (b) having a group reactive with a carbodiimide group. A method of making the described thermoplastic elastomer composition. The method for producing a thermoplastic elastomer composition according to any one of claims 1 to 8, wherein the olefin polymer (D) is a propylene polymer. With respect to a total of 100 parts by mass of the olefin polymer (B) having a group that reacts with the carbodiimide group, the polar rubber (C), and the olefin polymer (D), the composition in the step of dynamic crosslinking,
10. The method for producing a thermoplastic elastomer composition according to any one of claims 1 to 9, wherein the carbodiimide group-containing compound (A) is blended in an amount of 0.01 to 30 parts by mass. The method for producing a thermoplastic elastomer composition according to any one of claims 1 to 10, wherein the batch kneader has an intermeshing rotor.