JPS63105014A - Rubbery random copolymer - Google Patents

Abstract

PURPOSE:To provide the titled copolymer outstanding in heat and oil resistances and adhesivity to metal, useful for automobile parts, etc., constituted of specified composition of respective units of diene monomer, acrylonitrile, acrylic ester and amino group-contg. monomer. CONSTITUTION:The objective copolymer can be obtained by copolymerization, in an autoclave, between (A) a conjugated device such as butadiene, (B) a vinyl cyanide such as acrylonitrile, (C) an acrylic ester such as butyl acrylate, and (D) an aromatic amino group-contg. monomer such as N-(4-anilinophenyl) methacrylamide. This copolymer has a number-average molecular weight 40,000-120,000, being constituted of (i) 10-60wt% of a component of formula I (R<1> is H or methyl) (2) 10-40wt% of a second component of formula II (R<2> is H' or methyl), (3) 10-70wt% of a third component of formula III (R<3> is H or methyl; R<4> is 1-8C alkyl), and (4) 0.1-10wt% of a fourth component of formula VI (R<5>-R<7> are each H, 1-4C alkyl, etc.; R<9> and R<10> are each H, 1-4C alkyl, etc.; R'' is H, 1-4C alkyl, carboxymethyl, etc., R<12> is H, 1-4C alkyl, phenyl, etc.) or formula V (R<13>, R<14> are each H or 1-4C alkyl).

Description

[Detailed description of the invention] a. Industrial application field The present invention relates to a new rubbery random copolymer, more specifically, it has excellent heat resistance and oil resistance, and improved adhesion to metals. This invention relates to a rubbery random copolymer that can be widely used as automotive and industrial rubber products.

b. Prior art Generally, nitrile rubber (butadiene-acrylonitrile copolymer, hereinafter simply abbreviated as NBR), which is widely used as an oil-resistant rubber, has excellent oil resistance and processability, and is inexpensive. It has advantages such as:

However, NBR has the disadvantage of inferior heat resistance compared to special rubbers such as acrylic rubber and hydrin rubber.

Therefore, the present inventors conducted various studies to improve the heat resistance of NBR, and first proposed a conjugated diene-α,β-unsaturated nitrite-unsaturated carboxylic acid ester copolymer (Japanese Patent Application Laid-open No. 52-98048).

Problems to be Solved by the C0 Invention However, the cough conjugated diene-α,β-unsaturated nitrite-unsaturated carboxylic acid ester copolymer has poor adhesion to metals, and improvements in this respect have been desired.

Means for Solving the d0 Problem As a result of various studies on improving the above problems, the present inventors found that a specific The inventors have discovered that adhesion to metals can be improved by copolymerizing a copolymerizable aromatic amine compound, and have arrived at the present invention. That is, the present invention provides the following repeating units (A), (
B), (C) and (D), the composition ratios of which are (A) 10 to 60% by weight and (C) 10 to 40% by weight
, (C) 10-70% by weight and (D) 0.1-10
Number average molecular weight in weight% 40,000-1200.0
00 rubbery random copolymer.

■ (A) +CHz-C=CH-CHz÷, (B)
+coz-cu+ N (C) +GHz-C÷ KoC-0-R' (D) At least one type of repeating unit (A) selected from the following formulas [A] to [E] R” R” +C-CH÷ (0) RZ! Ri3 [2] RIS\R7 -(-C-CH÷.

e0 Detailed Description of the Invention Constituent Components> Repeating unit + CHz-C=CH-Cl in the rubbery random copolymer of the invention! The conjugated diene unit component (A) constituting the mirror includes butadiene, isoprene, 1,3-pentadiene, piperidine, etc., but butadiene, isoprene, and mixtures thereof are particularly preferred.

α,β-unsaturated nitryl compound unit (B) Also, α,β-unsaturated tolyl compound unit constituting the repeating unit Z + cuz-co+ N in the rubbery random copolymer of the present invention Examples of the component include acrylonitrile and methacrylonitrile, with acrylonitrile being particularly preferred.

The unsaturated carboxylic acid ester unit component (C) constituting +CH, -C÷C-0-R' includes ethyl acrylate, propyl acrylate, butyl acrylate, hexyl acrylate, octyl acrylate, and methacrylate. You can give things like octyl.

Aminhi A′ (D) Furthermore, the following general formulas [A] to [
As the aromatic amine compound unit component (D) having at least one repeating unit selected from (e), at least one aromatic amine compound selected from the following general formulas (e) to (e) is used.

General formula [A] R eye R12 General formula [mouth] RlZ R1ko\R7 General formula (d) RI8 ■\R7 -(-C-CI-) Exposure R1 (l Hll R14R1) R'-C-C-C -0-C-C=CHR'' General formula [W] General formula [NU] In the aromatic amine compounds of the above general formulas [H] and [H], the carbalkoxymethyl group preferably has the following structural formula.

-CH, -C-0-R'' Moreover, it is preferable that the carbalkoxy group has the following structural formula.

-C-0-R” Also, in the aromatic amine compound of the above general formula [to], R
Although 8 may be any other aryl group such as a naphthyl group with or without a substituent, it is preferably a phenyl group with or without a substituent. When R7 is a group with the following structure: 1) 72+ R? is preferably at the para position, and Ra is preferably a phenylene group with or without a substituent. R'l and RIG are preferably selected from the group consisting of a hydrogen atom and a methyl group. Preferably R9 is a hydrogen atom or a methyl group. Preferably R1)1 is a hydrogen atom. In the preferred carbalkoxymethyl and carbalkoxy groups, RZ4 and Ris are each preferably a methyl group or an ethyl group.

In the aromatic amine compound of the above general formula [g], R1 is preferably a hydrogen atom or a methyl group.

Preferably) 71) is a hydrogen atom.

In the aromatic amine compound of general formula [I], the carbalkoxymethyl group preferably has the following structural formula % Formula % where R14 is an alkyl group having 1 to 4 carbon atoms. Also, the carbalkoxy group preferably has the following structural formula % Formula % where RZS is an alkyl group having 1 to 4 carbon atoms.

In aromatic amine compounds of general formulas [C] to [N], R
1) is preferably a phenyl group, but may also be any other aryl group such as a naphthyl group.
When is a group having the structural formula, R'l is preferably in the para position.

R9 and RIG are preferably selected from the group consisting of hydrogen atoms and methyl groups.

In the aromatic amine compound of general formula [I], R7 is preferably selected from the group consisting of hydrogen and a methyl group. R24 and Hzs in the preferred carbalkoxymethyl group and carbalkoxy group are each preferably a methyl group or an ethyl group.

Specific examples of aromatic amine compounds represented by these general formulas include 4-anilinophenyl acrylate, 4-anilinophenyl methacrylate, 4-anilinophenyl crotonate, and 4-anilinophenyl cinnamate. , 4-anilinophenyl hydrogen maleate, 4-
Anilinophenyl hydrogen itaconate, 4-anilinophenyl methyl maleate, 4-anilinophenylethyl itaconate, 4-p-toluidinophenyl acrylate, 4-p-)luidinophenyl methacrylate, 4-
0-Toluidinophenyl methacrylate, 4-(p
-methoxyanilino) phenyl acrylate, 4-(p
-methoxyanilino) phenyl acrylate, 4-(p
-methoxyanilino)phenyl methacrylate, 4-
(p-ethoxyanilino)phenyl methacrylate,
4-(o-methoxyanilino)phenyl methacrylate, 4-(2',4'-dimethylanilino)
Phenyl methacrylate, 4-(4'-isopropylanilino)phenyl methacrylate, 4-(4
' -(N,N-dimethylamino)anilinophenyl acrylate, 4-(4' -(N,N-dimethylamino)anilinophenyl methacrylate, 4-(2'
-naphthylamino)phenyl methacrylate, 4-(
2'-naphthylamino) phenyl acrylate, 4-anilino-3-methylphenylacrylate, 4-anilino-2-methylphenylacrylate, 4-anilino-
3-methylphenyl methacrylate, 4-p-toluidino-2-methylphenyl methacrylate, 4-(p
-methoxyanilino)-3-methylphenyl methacrylate, 4-anilino-2,5-dimethylphenyl methacrylate, 4-p-1 luidinophenylethyl maleate, 4-(p-ethoxyanilino)phenyl hydrogen maleate and so on.

Further, specific examples of the aromatic amine compound represented by the general formula [g] include 3'(4'-anilinophenyl)-2' -hydroxypropyl methacrylate,
3'-N-(4"-anilinophenyl)amino2
'-Hydroxy-1'-methylpropyl methacrylate, 3'-N-(4"-anilinophenyl)amino-2'-hydroxy-1', 2', 3'-trimethylpropyl methacrylate, 3'-N -(4#
-anilinophenyl)amino-2'-hydroxy-1'
, 1'-di-n-butylpropyl methacrylate, 3'-N-(4'-anilinophenyl)amino-2'-hydroxypropyl acrylate, 3'-
N-(4"-anilinophenyl)amino-2'-hydroxypropyl-2-methoxymethacrylate, 3'
-N-(4"-anilinophenyl)amino-2' -
Hydroxypropyl-2-carboxymethacrylate, 3'-N-(4"-anilinophenyl)amino-
2'-Hydroxypropyl-2-carboxymethacrylate, 3'-N-(4'-anilinophenyl)amino-2'-hydroxypropyl-3-phenylmethacrylate), 3'-N-(4# -anilinophenyl)amino-2'-hydroxypropyl-3-methoxymethacrylate, 3'-N-(4'-anilinophenyl)amino-2'-hydroxypropyl-3-(4-
carboxyphenyl) methacrylate, 3' -N-
(4"-anilinophenyl)amino-2'-hydroxypropyl-3-(4-carbomethoxyphenyl)methacrylate, 3'-N-(4'-anilinophenyl)-N-isopropylamino-2'- Hydroxypropyl methacrylate, 3'-N-(4"-anilino-3"-methylphenyl)amino-2'-hydroxypropyl methacrylate, and the like.

Specific examples of the aromatic amine compound represented by the general formula [I] include N-(4-anilinophenyl)acrylamide, N-(4-anilinophenyl)methacrylamide, and N-(4-anilinophenyl)methacrylamide. Anilinophenyl)cinnamamide, N-(4-anilinophenyl)crotonamide, N-(4-(4-methylanilino)phenylcoacrylamide, N-(4-(4-methylanilino)phenyl)methacrylamide , N-(4-(4-methoxyanilino)phenylcoacrylamide, N-(4
-(4-methoxyanilino)phenyl]methacrylamide, N-(4-(4-ethoxyanilino)phenylcoacrylamide, N-(4-(4-ethoxyanilino)phenyl)methacrylamide, N -(4-(4
-N,N-dimethylaminoanilino)phenylcoacrylamide, N-(4-anilinophenyl)maleamic acid, N-(4-anilinophenyl)itaconamic acid, N-(4-(4-methylanilino) ) phenylcomaleinamide M, N-(4-7nylinophenyl)citraconamic acid, and the like.

Specific examples of the aromatic amine compounds represented by the general formulas [S] and [N] include N-(N-anilinophenyl)maleimide, N-(4-anilinophenyl)metaconimide, N- -(4-anilinophenyl)citraconimide, N-(4-(4-methylanilino)phenylcomaleimide, N-(4-(4-methoxyanilino)phenyl)itaconimide, N-(4-(
4-methoxyanilino)phenylcomaleimide, N
-(4-(4-methoxyanilino)phenyl]itaconimide)', N-(4-(4-ethoxyanilino)phenylcomaleimide, N-(4-(4-ethoxyanilino)phenyl)itaconimide, N-(4-(4-ethoxyanilino)phenylcocitraconimide, N-(4
-anilinophenyl)phenylmaleimide, N-(
Examples include 4-(4-N,N-dimethylaminoanilino)phenylcomaleimide.

Production of rubbery random copolymer> The monomers constituting each of the components (A) to (D) are added in a predetermined amount, for example, under preferable conditions, conjugated diene monomer (A)
20-50% by weight of α,β-unsaturated nitrile monomer (B
) 20 to 30% by weight, unsaturated carboxylic acid ester monomer (C) 20 to 50% by weight, and aromatic amine compound monomer (D) 0.3 to 7% by weight in an aqueous medium or organic Obtained by radical polymerization in a solvent or the like.

The polymerization is generally carried out in an oxygen-free reactor at a temperature of generally 0 to 80°C, preferably 0 to 50°C, and under a pressure of 1 to 7 kg/-.

In the polymerization reaction, each monomer or polymerization agent may be added in its entirety before the start of the reaction, or may be added in arbitrary portions after the start of the reaction. Further, operating conditions such as polymerization temperature and stirring can be arbitrarily changed during the reaction. The polymerization method may be either continuous or batch.

As the molecular weight regulator, tertiary dodecyl mercaptan, dialkyl xanthogen disulfide, etc. are used.

The amount used is preferably 0.1 to 5 g per 100 g of monomer.

The radical polymerization initiators used include organic peroxides such as benzoyl peroxide, cumene hydroperoxide, paramenthane hydroperoxide, and lauryl peroxide, diazo compounds represented by azobisisobutyldinitrile, and organic peroxides represented by potassium persulfate. Compounds, redox catalysts typified by combinations of organic compounds and iron sulfate, and the like are used.

(Rubbery random copolymer) The rubbery random copolymer of the present invention produced in this manner has a number average molecular weight (:1.) in terms of polystyrene of 40,000 to 1,200,000, preferably 100,000 to 100,000. It is important that the number average molecular weight is less than 40,000,000, the physical properties of the vulcanizate are poor, and when it exceeds 1,200,000, the processability is poor.

The composition of each unit component in the rubbery random copolymer of the present invention is as follows.

The content of the conjugated diene unit component (A) is 10 to 60% by weight
and preferably 20 to 50% by weight. If the amount is less than 10% by weight, the rubber elasticity will be poor, and if it exceeds 60% by weight, the heat resistance will be decreased.

The content of the tolyl unit component for α,β-unsaturation is 10
The content is preferably 20 to 30% by weight, preferably 20 to 30% by weight. If it is less than 10% by weight, oil resistance will be poor, and if it is less than 40% by weight.
If it exceeds this value, the rubber elasticity will be poor.

The content of unsaturated carboxylic acid ester unit component (C) is 1
It is 0 to 70% by weight, preferably 20 to 60% by weight. If it is less than 10% by weight, problems such as poor heat resistance and imbalance between oil resistance and cold resistance will occur. 7
If it exceeds 0% by weight, processability will deteriorate.

The f content of the aromatic amine compound unit component (D) is 0.1
-10% by weight, preferably 0.3-7% by weight. (
If the amount of component D) exceeds 10% by weight, the strength and elongation of the material will deteriorate, which is not preferable. If the amount is less than 0.1% by weight, the resulting rubbery random copolymer will have poor adhesion to metal.

The rubbery random copolymer of the present invention is blended with a filler and a vulcanizing agent and used as a vulcanized rubber.

The filler used in the rubbery random copolymer of the present invention is the carbon blank used in -a, white carbon, carbonate calcillamine, white gloss, titanium white, etc., and it is also possible to use these in combination. The amount used is 20 to 400 parts by weight, preferably 40 to 100 parts by weight, per 100 parts by weight of the rubbery random copolymer.

Vulcanizing agents include sulfur and peroxides,
Sulfur is preferred. The amount used is 0.1 to 5 parts by weight, preferably 0.1 to 0.5 parts by weight, per 100 parts by weight of the rubbery random copolymer.

In addition, ordinary compounding agents such as reinforcing agents, softeners, and anti-aging agents can be added as appropriate.

f. Examples Hereinafter, the present invention will be further explained with reference to Examples and Comparative Examples. Note that all percentages and parts shown in the examples mean percentages by weight and parts by weight.

1-15, ' 1-9 According to the polymerization recipe shown in Table 1, the reaction was carried out using an autoclave with an internal volume of 6 Il at a reaction temperature of 5°C until the monomer conversion rate reached 80%. After the reaction was completed. , 0.5 part of sodium dimethylthiocarbamate was added to stop the polymerization.Next, 1 part of alkylated diphenylamine was added as a stabilizer to the reaction solution, unreacted monomers were removed by steam distillation, and sulfuric acid The random copolymer produced by adding aluminum was solidified. After washing the coagulated random copolymer with water, it was dried using a vacuum dryer.

Table 1 The infrared absorption spectrum of the obtained polymer is shown in FIG.

Various rubbery random copolymers were produced in the same manner.

5 parts of zinc oxide was added to 100 parts of the obtained rubbery random copolymer.
parts, stearic acid 1 part, HAF carbon 60 parts, hydrous silicic acid 10 parts, dioctyl phthalate 20 parts, sulfur 0.1
5 parts, 1 part of tetramethylthiuram disulfide and N
After adding 1 part of -cyclohexyl-2-benzothiazylsulfenamide and mixing with a roll, press vulcanization was performed at 160°C for 15 minutes to obtain a vulcanized sheet. The physical properties of the rubbery random copolymer and the vulcanized sheet are shown in Table 2 and Table 3. The test method is JIS K6301
The measurement method described in was followed.

The aromatic amine compound unit component (D) of the rubbery random copolymer was analyzed by the following method.

(2) Using a sample with a known concentration of monomer (D), measure the ultraviolet absorbance using an ultraviolet analyzer, and draw a calibration curve. From the calibration curve diagram, the following relational expression is derived.

I.

-X100 X100 ■ I.

(here -: ultraviolet absorbance, W: sample amount of monomer)■
The sample of the present invention is analyzed using an ultraviolet analyzer, the amount of ultraviolet absorbance is determined, and the amount of bound monomers is determined from the formula (2) above.

The sample preparation conditions and ultraviolet measurement conditions at that time were as follows.

Sample Preparation ■ Extract the rubbery random copolymer with ethyl alcohol and dry in a vacuum dryer at 60°C overnight.

(2) Dissolve 40 mg of the rubbery random copolymer prepared in (2) in 100 cc of chloroform and use this as a sample.

Analysis conditions (a) Equipment: Model 323, Hitachi self-recording spectrophotometer (BL) Quantitate the copolymerized (D) by analysis in the wavelength range 210-36ON or higher, and perform elemental analysis of the polymer (CSH, N, 0). The composition of each polymer is determined by combining the results.

The number average molecular weight (Mfi) in terms of polystyrene was measured as follows according to "Gel Permeation Chromatograph" by Takeuchi, published by Maruzen.

■ Use standard polystyrene with a known molecular weight (manufactured by Pressure Chemical ■, monodisperse polystyrene) to determine the molecular weight M and its GPC (Gel Permeation Chro
matograph) counts and molecular weights M and E
A correlation diagram calibration curve of V (Elution Volume) is drawn. The concentration at this time is 0.2% by weight.

(2) Obtain a GPC pattern of a sample of the rubbery random copolymer of the present invention using the GPC measurement method, and determine the molecule 'IM in terms of polystyrene from the above (2). (Data used has been subjected to broadening processing. The broadening method was carried out according to the literature (Oka Journal 73 (41P124 (1970)).

The sample preparation conditions and GPC measurement conditions at that time are as follows.

Sample preparation a) Anti-aging agent Noera in tetrahydrofuran solvent
Add 0.1% by weight of cNS-6 (manufactured by Iriuchi Shinko ■) and dissolve.

b) A sample of the rubbery random copolymer is taken into an Erlenmeyer flask and dissolved in a tetrahydrofuran solvent at a concentration of 0.4% by weight.

c) Filter the sample solution with a 1 μm membrane filter.

d) Apply the filtered solution to GPC.

GPC measurement conditions a) Apparatus 200 type manufactured by Waters b) Column -a Sty manufactured by Tars
ragelC) Sample amount 1500μJ d) Temperature Room temperaturee) Flow rate lml/lll1n
Roll processability was evaluated based on the roll windability and the state of the rubber when kneading the rubber with a roll, and was evaluated based on the following criteria.

A (Excellent): Smoothly wrapped around two rolls, and kneading is extremely easy.

B (Good) Two rolls wound, the kneading is easy as there is little separation from the rolls, but the biting into the rolls is somewhat poor.

C (Acceptable): Wraps around the roll, but easily separates from the roll.

However, kneading is possible.

The adhesion of the rubbery random copolymer compound to metal was evaluated by the method described in JIS K6301, in which the rubber adhered to a metal piece was peeled off at 90°. An unvulcanized rubber of a rubbery random copolymer was placed on a soft steel plate in a mold (the surface of the I plate was coated with an adhesive, Metalloc NC (Toyo Kagaku Institute type), and dried at room temperature day and night). ℃×2
Steam press vulcanization is carried out in 0 minutes. When the obtained vulcanizate was peeled off from the metal surface, the state of adhesion of the rubber remaining on the metal surface without being peeled off was evaluated. The evaluation criteria are as follows.

A Rubber adhesion rate 100% Good C
50% Adhesion to metals E〃O% Poor g1 Effects of the invention The vulcanized product of the rubbery random copolymer according to the present invention has excellent oil resistance and heat resistance, and has good adhesion to metals. be.

Taking advantage of these good physical properties, we manufacture oil cooler hoses, air duct hoses, power steering hoses,
Various hose materials such as intercooler hoses, torque converter hoses, oil return hoses, heat-resistant hoses, bearing seals, bulk stem seals, various oil seals, 0
−Sealing materials such as rings, gaskets, gaskets, various diaphragms, rubber plates, belts, oil level gauges,
It is extremely useful industrially because it can be used for hose masking, coating materials such as pipe insulation, and rolls.

[Brief explanation of the drawing]

FIG. 1 is an infrared cotton spectrum diagram of the rubbery random copolymer of the present invention produced in Example 1.

Claims (2)

[Claims] (1) Consists of the following repeating units (A), (B), (C) and (D), the composition ratio of which is (A) 10 to 6
0% by weight, (B) 10-40% by weight, (C) 10-70
A rubbery random copolymer having a number average molecular weight of 40,000 to 1,200,000, and (D) 0.1 to 10% by weight. (A) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [However, R^1 indicates a hydrogen atom or a methyl group. ]
(B) ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ [However, R^2 represents a hydrogen atom or a methyl group. ]
(C) ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ [However, R^3 represents a hydrogen atom or a methyl group, and R^4 represents an alkyl group having 1 to 8 carbon atoms. ] (D) At least one type of repeating unit selected from the following formulas [A] to [E] [B] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [B] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [C] ]▲There are mathematical formulas, chemical formulas, tables, etc.▼ [D]▲There are mathematical formulas, chemical formulas, tables, etc.▼ [E]▲There are mathematical formulas, chemical formulas, tables, etc.▼ [However, R^5 and R^6 are hydrogen atoms , an alkyl group having 1 to 4 carbon atoms, and an alkoxy group having 1 to 4 carbon atoms, and R^7 is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, and an alkoxy group having 1 to 4 carbon atoms. and ▲ formula,
There are chemical formulas, tables, etc. The group represented by ▼ (however, R
^2^0 is an alkyl group with 1 to 12 carbon atoms, 5 to 1 carbon atoms
2 cycloalkyl group, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 13 carbon atoms, R^
2^1 is selected from a hydrogen atom and an alkyl group having 1 to 12 carbon atoms. ), R^8 is an aryl group, R^9, R^1^0, R^1^3R^1^4, R^1
^5, R^1^6, R^1^7 are selected from a hydrogen atom and an alkyl group having 1 to 4 carbon atoms, and R^1^1 is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, carboxymethyl and carbalkoxymethyl group, R^1^2 is selected from hydrogen atom, alkyl group having 1 to 4 carbon atoms, phenyl and substituted phenyl, carboxyl group and carbalkoxy group, R^1^8 is hydrogen Atom, carbon number 1-12
an alkyl group having 5 to 12 carbon atoms, a cycloalkyl group having 5 to 12 carbon atoms, and an aralkyl group having 7 to 24 carbon atoms, R^1^9 is a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 5 to 12 carbon atoms , an aralkyl group having 7 to 24 carbon atoms, and an aryl group having 6 to 24 carbon atoms, R^2^
2 is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, and 6 to 4 carbon atoms.
12 aryl group, aralkyl group having 7 to 13 carbon atoms,
selected from a cycloalkyl group having 5 to 12 carbon atoms, a carboxymethyl group, and a carbalkoxymethyl group, R^
2^3 is selected from a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 12 carbon atoms, a cycloalkyl group having 5 to 12 carbon atoms, a carboxyl group, and a carbalkoxy group. ] (2) A rubber-like material according to claim (1), which is obtained by radical copolymerizing the copolymer unit components (A), (B), (C), and (D) at a polymerization temperature of 0 to 50°C. Random copolymer.