JPH0410891B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a chloroprene rubber composition that can be turned into a vulcanizate having an interpenetrating polymer network structure, and a method for producing the same. In more detail, the cold resistance (embrittlement resistance), ozone resistance (weather resistance), oil resistance, heat resistance, anti-vibration properties of conventional chloroprene rubber vulcanizates,
A chloroprene vulcanizate with greatly improved fatigue properties and tear strength, in which polychloroprene segments and urethane segments form a highly and finely intertwined structure, with each segment forming a unique network structure. The present invention relates to rubber compositions. [Prior Art] Conventionally, the following method has been adopted as a method for modifying chloroprene rubber. A copolymerizable monomer is added during the polymerization stage of chloroprene rubber. Change the polymerization temperature of the chloroprene rubber polymerization step. The type and amount of chain transfer agent are changed during the polymerization stage of chloroprene rubber. The type or amount of softeners, hardeners, reinforcing agents, fillers, anti-aging agents, or vulcanization accelerators to be blended is changed during the processing of chloroprene rubber. Other polymers are added during the processing of chloroprene rubber. [Problem to be solved by the invention] Since 2-chloro-1,3-butadiene is a monomer with extremely high radical polymerization activity, it cannot be easily separated from other monomers except for specific monomers. It does not copolymerize and is industrially very difficult. Regarding physical properties modified by polymerization temperature, except for extreme temperature conditions, the only property modified is the crystallinity of the polymer. Although it can be used, it is a factor that has little involvement in other functions. Also, the effect of improving physical properties is small,
It does not fall outside the scope of conventional chloroprene rubber. This is the most general-purpose modification method, and various physical property modification effects can be expected depending on the combination of additives. However, Shiyosen is an "additive" and cannot form chemical bonds with the polymer main chain. They tend to be removed, their functions are destroyed, and their property-modifying effects tend to be lost. As for chloroprene rubber, co-vulcanization with other elastomers is extremely difficult.
You can only expect similar results. The present invention was discovered as a result of repeated trial and error of a wide variety of modification means in order to modify chloroprene rubber into a higher-dimensional elastomer. [Means for Solving the Problems] That is, the present invention provides a component A containing 100 parts by weight of chloroprene rubber and a vulcanizing agent for chloroprene rubber. Component B comprising 5 to 100 parts by weight of polyester polyol or polyether polyol, 0 to 15 parts by weight of low molecular weight polyol and polyisocyanate. 2 isocyanate groups in one molecule as functional groups
Component C, which contains 5 to 100 parts by weight of a prepolymer having at least 100% polyisocyanate, 0 to 10 parts by weight of a low molecular weight polyisocyanate, and one or more compounds selected from the group consisting of polyamines, polyols, polycarboxylic acids, and water. Consists of a combination of the above components A and B, or components A and C, at any temperature (temperature T)
Let _tA be the time required for the first-order differential coefficient of the rising curve of the torsional moment of component A to reach its maximum at tA, and separately from this, the first-order differential curve of the rising curve of the torsional moment of only component B or component C at temperature T. Relating to a chloroprene rubber composition characterized in that the maximum times are t _B and t _C, respectively, and the composition is in the range of 0.9t _A ≦t _B ≦1.1t _A 0.9t _A ≦t _C ≦1.1t _A. The composition is heated to a temperature T
When vulcanization is performed in (weather resistance), oil resistance, heat resistance, anti-vibration properties, fatigue properties, and tear strength are significantly improved. Note that _tA , tB, or tC, which is the time required for the first-order differential curve of the torsional moment increase curve of component A, _B , or _C in the present invention to reach a maximum, is, for example, the vulcanization test according to the Japan Rubber Association standard. This is the maximum point on the first-order differential curve of the time-torque curve measured in accordance with the machine vulcanization test method (SRIS-3102-1977). etc. can be used. In this way, the present invention introduces a polyurethane crosslinked structure into a chloroprene rubber vulcanizate, and each crosslinked structure is not essentially connected by chemical bonds, but each molecular chain is connected physically. By combining essentially insoluble chloroprene and urethane, we were able to develop properties that could not be expected from the physical properties of conventional chloroprene. As an explanation of the terms used in this specification, the polyester polyol of component B is a compound whose main chain has the structure of a polyester polymer and which has an average of two or more hydroxyl groups as a functional group in one molecule. Polyether polyol means that the main chain has a polyether polymer structure,
Also, it refers to a compound having an average of two or more hydroxyl groups as a functional group in one molecule, and the number average molecular weight of both refers to a compound having a number average molecular weight in the range of 500 to 10,000. Low molecular weight polyol refers to a compound having two or more hydroxyl groups in one molecule and having a molecular weight of less than 500. Polyisocyanate refers to a compound having two or more isocyanate groups in one molecule,
The isocyanate group may be preliminarily reacted with an oxime compound or a phenol compound, that is, it may be in the form of a blocked isocyanate. The prepolymer of component C generally refers to a polymer in which the above-mentioned polyester polyol or polyether polyol is reacted with a low molecular weight polyisocyanate so that the functional group is an isocyanate group, but the present invention is not particularly limited to these. figure,
Also included are isocyanate-functional prepolymers whose main chain is, for example, a diene-based polymer or a polyalkylene polymer. Further, the isocyanate group may be in the form of a blocked isocyanate, which has been preliminarily reacted with an oxime compound or a phenol compound. Low molecular weight polyisocyanate has two or more isocyanate groups in one molecule, and the molecular weight per isocyanate group is
Indicates 500 or fewer compounds. Further, the isocyanate group may be in the form of a blocked isocyanate, which has been preliminarily reacted with an oxime compound or a phenol compound. Polyamine refers to a compound having two or more amino groups or imino groups in one molecule. Polyol refers to a compound having two or more hydroxyl groups in one molecule. Polycarboxylic acid refers to a compound having two or more carboxyl groups in one molecule. Originally, urethane elastomers are elastomers that have an extremely high balance of physical properties except for water resistance. Further, urethane elastomers using general-purpose polyisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.) have yellowing properties, but the degree of yellowing is slight compared to diene-based elastomers. However, the most distinctive feature of urethane elastomers is their crosslinking method. General elastomers are raw rubber in the form of chips, blocks, flakes, or powder.
While kneading it with a roll or Banbury,
A processing method is used in which compounding reagents such as vulcanizing agents are kneaded, then placed in a mold and crosslinked at high temperature and pressure to obtain a vulcanizate. As the vulcanizing agent, sulfur, sulfur compounds, metal oxides, peroxides, etc. are used. In the case of chloroprene rubber, a vulcanizate is obtained by the same operation. There are various theories about the crosslinking mechanism of chloroprene rubber, and it is not certain, but in general, one or two units (see the formula below) in the molecular chain become the crosslinking unit, and the chlorine atom is extracted, or a pendant double bond is formed. The theory that it is due to partial cleavage is supported. On the other hand, in urethane elastomers, the base that forms the main chain is generally liquid, and a combination of polyether or polyester having hydroxyl groups at both ends as the main ingredient, polyisocyanate as a curing agent, and polyether having isocyanate groups at both ends. Alternatively, a combination in which polyester is used as the main ingredient and a compound having two or more functional groups containing active hydrogen, such as polyamino, polyol, polycarboxylic acid, or water, is used as a curing agent is common. The crosslinking mechanism of urethane elastomers is a reaction that is well within the scope of organic synthetic chemistry, and includes an addition reaction between an isocyanate group and an active hydrogen-containing group, an addition reaction between a urea bond and an isocyanate group (Biuretz bond), and an addition reaction between a urethane bond and an isocyanate group. It can be summarized by three addition reactions (allophanate bond). In this way, the crosslinking mechanisms of chloroprene rubber and urethane elastomer are completely different, and the main raw material of urethane elastomer is liquid, so it can be easily incorporated into unvulcanized chloroprene rubber like a plasticizer. be. Focusing on this point, we investigated the possibility of producing a vulcanizate having an interpenetrating polymer network structure of urethane and chloroprene, and arrived at the present invention. According to the invention, it is added to 100 parts by weight of polychloroprene. The polyester polyol or polyether polyol in component B is from 5 to
It is specified as 100 parts by weight, but if it is less than 5 parts by weight,
If the effect of the present invention is lost and the amount exceeds 100 parts by weight,
This is because the properties of chloroprene rubber tend to be lost, and the compound itself has an extremely low viscosity, making it difficult to handle with conventional chloroprene rubber processing methods and equipment. Similarly, the low molecular weight polyol in component B is defined as 0 to 15 parts by weight. The purpose of adding such substances is to modify the physical strength of the product. However, if the amount exceeds 15 parts by weight, undesirable properties such as an increase in the embrittlement point of the resulting vulcanizate tend to occur, and a transition from elastomer-like to plastic-like occurs.
It is necessary to limit the amount to parts by weight or less. In component B, a polyester polyol or a polyether polyol and a polyisocyanate as a polyol crosslinking agent are added as essential components. When determining the amount of polyisocyanate added, it is necessary to consider the effects of humidity during processing, amount of moisture absorbed in the compound, and standing time from compounding to vulcanization, etc. A range of 0.9 to 1.5 equivalents is preferred. Further, the isocyanate group may be in the form of a blocked isocyanate, which has been preliminarily reacted with an oxime compound or a phenol compound. The prepolymer having two or more isocyanate groups as a functional group in one molecule in component C has 5 to
The amount is limited to 100 parts by weight, but the reason is the same as for the polyester polyol and polyether polyol in component B. 0 to 10 parts by weight of a low molecular weight polyisocyanate is added to component C, and the purpose and reason for setting the upper limit are the same as for the low molecular weight polyol in component B. The isocyanate group in these prepolymers or low molecular weight isocyanates may be in the form of a blocked isocyanate, which has been preliminarily reacted with an oxime compound, a phenol compound, or the like. In component C, one or more of polyamine polyol, polycarboxylic acid, and water is added as a crosslinking agent for the prepolymer and the low molecular weight polyisocyanate. This addition amount is based on the total isocyanate groups in the prepolymer and low molecular weight isocyanate.
It is preferably in the range of 0.7 to 1.2 equivalents. Here, the amount to be added can be determined by evaluating that the amino group or imino group in the polyamine has a functionality of 1, and the functionality of water has a functionality of 2. In addition, during the crosslinking reaction, polycarboxylic acid and water release carbon dioxide gas and cause foaming of the crosslinked product, so it is not preferable except for special uses such as sponges and fillers, and polyamine is suitable. The present invention consists of a combination of component A and component B, or component A and component C, and the time required for the first derivative of the increase curve of the torsion moment of component A to reach a maximum at a given temperature (temperature T). _tA
Separately from this, when the times at which the first-order differential curve of the torsional moment rise curve at temperature T for only component B or component C reaches its maximum are t _B and t _C , respectively, 0.9t _A ≦t _B ≦1.1t _A 0.9t _A ≦t _C ≦1.1t _A must be in the range. If this range is exceeded, the modification effect of chloroprene rubber targeted by the present invention, that is, the modification of cold resistance, weather resistance, oil resistance, heat resistance, anti-vibration properties, fatigue properties, and tear strength, will not be sufficient. There is a tendency. The reason is not clear, but it is thought to be because chloroprene and urethane undergo phase separation in the vulcanizate. Chloroprene rubber does not need to be limited to a homopolymer of 2-chloro-1,3-butadiene, and may be a copolymer with other monomers. The copolymerizable monomer is one selected from the group consisting of 1-chloro-1,3-butadiene, 2,3-dichloro-butadiene, methyl methacrylate, methyl acrylate, methacrylic acid, acrylic acid, styrene, and acrylonitrile. The above monomers are preferred, and the amount thereof is limited to 0 to 50 parts by weight. This is because if the amount exceeds 50 parts by weight, the excellent balance of physical properties of chloroprene rubber can no longer be maintained. In addition to the essential components of chloroprene rubber and vulcanizing agent, component A may contain anti-aging agents, vulcanization accelerators, fillers, reinforcing agents, and/or softeners, etc., in any proportion, if necessary. I can do it. In addition, component B
A crosslinking accelerator may also be added to component C to control the crosslinking rate. As specific examples of compounds used in the present invention, first, chloroprene rubber vulcanizing agents include zinc white,
Metal oxides such as magnesium oxide and red lead, sulfur,
Examples include sulfur compounds such as tetraalkylthiuram disulfide and various organic peroxides. Other substances optionally included in component A include anti-aging agents, vulcanization accelerators, fillers, reinforcing agents, and softeners (plasticizers). Examples of anti-aging agents include phenyl-α-naphthylamine, N- Isopropyl
N'-phenyl-p-phenylenediamine, p-
Diphenylamine etc. are used as vulcanization accelerators.
-Mercaptoimidazoline, trimethylthiourea, diethylthiourea, diphenylguanidine, etc. are used as fillers, calcium carbonate, clay, talc, etc. are used as fillers, various carbon blacks, silica, etc. are used as reinforcing agents, and dioctyl is used as a softener (plasticizer). Examples include phthalate, dioctyl sebacate, trioctyl phosphate, process oil, rapeseed oil, and sub. Next, examples of compounds contained in component B are shown. First, as an example of polyester polyol,
Examples include polyester diols of ethylene glycol and adipic acid, polyester diols of caprolactone, and polyester diols of 1,4-butanediol, ethylene glycol and adipic acid. Examples of polyether polyols include:
Examples include polypropylene glycol and polytetramethylene glycol. Examples of polyisocyanates used as crosslinking agents include tolylene diisocyanate, diphenylmethane-4,4'-
Diisocyanates, isophorone diisocyanates, etc. may be mentioned, and these polyisocyanates may be blocked with phenol compounds and oxime compounds. Examples of low molecular weight polyols include 1,4-butanediol, dipropylene glycol, trimethylolpropane, and the like. Cross-group promoters added if necessary include 1,8-diazobicyclo(5,4,0)undecene-7, its organic acid salt,
and various metal soaps. An example of a compound contained in component C is a prepolymer having two or more isocyanate groups in one molecule. It is common to have a structure in which the center is added. Although there are commercially available products, polyisocyanate is added to polyester polyol or polyether polyol so that hydroxyl group/isocyanate group ≧2, and while stirring in a stream of dry nitrogen, 80 to 120
It can be easily obtained by reacting at a temperature of 4 to 7 hours. Further, the isocyanate groups of these prepolymers can be preliminarily reacted with a phenol compound or an oxime compound to form a blocked isocyanate. Blocking can also be in the form of active hydrogen groups in the phenolic compound or oxime compound and isocyanate in the prepolymer. Blocking is performed by mixing approximately equivalent amounts of hydroxyl groups in phenols or oximes and isocyanate groups in the prepolymer, and
This can be easily achieved by reacting at 110°C for 10 to 30 hours. The purpose of blocking is to retard the crosslinking rate. Examples of low molecular weight polyisocyanates are
Similar to the polyisocyanate example in component B above. Examples of crosslinking agents used include 4,4'-methylenebis(2-chloraniline) for polyamines, and hydroquinone-bis(2-chloraniline) in addition to the low molecular weight polyol in component B for polyols.
-hydroxy) ether and the like. Examples of the polycarboxylic acid include malonic acid and phthalic acid, but as described above, the combination of polycarboxylic acid and water is not very preferable because it causes foaming of the vulcanizate. Examples of crosslinking accelerators are similar to those in component B above. The composition obtained according to the present invention is made into a vulcanized product by a vulcanization operation and is put into practical use, but there are no particular restrictions on the vulcanization equipment and conditions, but the vulcanization temperature is From the viewpoint of productivity and reproducibility of vulcanized physical properties, the temperature is preferably 100 to 200°C. In view of the gist of the invention, it is also assumed that vulcanization is carried out at the temperature at which the above-mentioned increase in torsional moment is measured, and that t _A , t _B , and t _C at that temperature satisfy the following correlation. Needless to say, this is a prerequisite. 0.9t _A ≦t _B ≦1.1t _A 0.9t _A ≦t _C ≦1.1t _A [Example] Next, in order to make the present invention even easier to understand,
Comparative examples and examples are shown. Note that the invention is not limited in any way by the following Examples and Comparative Examples. Amounts, parts and percentages of formulations are given on a weight basis unless otherwise stated. In addition, the polychloroprene rubber used in each example,
Vulcanizing agents, anti-aging agents, vulcanization accelerators, reinforcing agents, softening agents, polyether polyols, polyester polyols, prepolymers, low molecular weight polyols, low molecular weight polyisocyanates, polyamines, polyols, and crosslinking accelerators are indicated by abbreviations. However, the contents are as follows. CR: Polychloroprene rubber "Denka chloroprene M-" manufactured by Denki Kagaku Kogyo Co., Ltd.
40" MgO: Chloroprene rubber vulcanizing agent, magnesium oxide "Kiyowa Magoo 30" manufactured by Kyowa Chemical Industry Co., Ltd. ZnO: Chloroprene rubber vulcanizing agent, zinc oxide "Zinc Hua No. 1" manufactured by Sakai Chemical Industry Co., Ltd. PA: Anti-aging agent for chloroprene rubber, phenyl-α-naphthylamine “Nokrac PA” manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd. Prompt-22: Vulcanization accelerator for chloroprene rubber, 2-
Mercaptoimidazoline "Accel 22" manufactured by Kawaguchi Chemical Industry Co., Ltd. CB: Reinforcing agent for chloroprene rubber, SRF Carbon Black "Asahi #50" manufactured by Asahi Carbon Co., Ltd. Rapeseed oil: Softening agent for chloroprene rubber, Ajinomoto
Co., Ltd. PTMG: polyether polyol, polytetramethylene glycol, Nippon Polyurethane Kogyo Co., Ltd. ``PTG-200'',
Hydroxyl value = 100 PAEG: Polyester polyol, adipic acid/ethylene glycol polyester polyol Nipporan Polyurethane Industries Co., Ltd.
4002", hydroxyl value = 112 PP-1: Prepolymer, NCO-functional prepolymer based on polytetramethylene glycol "Hyprene L-100" manufactured by Mitsui Nisso Urethane Co., Ltd. NCO group content = 4.2% PP-2: Prepolymer, acetoxime per 100 parts of the above "Hyprene L-100"
9.5 parts, reacted at 70°C for 22 hours to form a blocked isocyanate prepolymer DPG: Low molecular weight polyol, dipropylene glycol reagent, purchased from Wako Pure Chemical Industries, Ltd., molecular weight = 134 MDI: Low molecular weight polyisocyanate, diphenylmethane -4,4'-Diisocyanate "MDI-PH" manufactured by Mitsui Nisso Urethane Co., Ltd. NCO group content = 29% MOCA: Polyamino, 4,4'-methylene-bis-(2-chloroaniline) Ihara Chemical Industry Co., Ltd. ) made by ``Ihara Kiyu Amin''
MT” _NH2 group content = 12% HNE: Polyol, hydroquinone bis-
(2-Hydroxyethyl)ether Ihara Chemical Industry Co., Ltd. "Ihara Kyuamine H" Hydroxyl group content = 17% CAT: crosslinking accelerator, 1,8-diaza-bicyclo(5,4,0) undecene-7 mainly composed of oleic acid "V-Cat SA No. 106" sold by Sanyo Kasei Co., Ltd. Tables 1, 2, and 3 show the first derivatives of the torsional moment increase curves for components A, B, and C at various temperatures. The times t _A , t _B , and t _C at which the peaks occur are shown. Here, how to obtain t _A , t _B , and t _C will be explained below by way of example. First, for component A, an oscillating disk rheometer was used to obtain torsional moment increase curves as shown in FIG. 1 under various vulcanization temperature conditions. Based on FIG. 1, at times t ₁ and t ₂ (=t ₁ +Δt). Read the torsional moments y ₁ , y ₂ (=y ₁ +Δy). The first derivative of the torsional moment (the slope of the torsional moment increase curve) in the minute interval t ₁ to _{t 2} is given by (y ₂ − y ₁ )/(t ₂ − t ₁ )=Δy/Δt, which can be expressed as: Let it be the first-order differential coefficient at the midpoint between t ₁ and t ₂ ((t ₁ + t ₂ )/2). In addition, in the above, Δt
was set to 20 seconds. Similarly, read the torsional moments y _o and y _o+1 at arbitrary times t _o and t _o+1 , and read the first derivative coefficient Δy/Δt
seek. Next, the first derivative of the torsional moment at each time is plotted to obtain Figure 2. In Fig. 2, the time when the first-order differential coefficient reaches its maximum is _tA . For components B and C, use a culastometer instead of an oscillating disk rheometer to obtain torsion moment increase curves under each vulcanization temperature condition, and determine t _B and t _C according to the above method. Also, a method for achieving t _B and t _C with respect to t _A will be explained. First, for components B and C, t B and _{t C} are determined under the same temperature conditions as the temperature at which t _A was determined, assuming the respective formulations. If this value deviates from the conditions of the present invention, the blending recipe of the deviating components is changed and the time at which the first-order differential coefficient reaches its maximum is determined again. By repeating the above operations, the t _B value and
t Achieve _C value. Table 4 shows composition formulations and vulcanization conditions of Examples included within the scope of the invention and Comparative Examples when deviating from the range, and Table 5 shows various physical properties of the obtained vulcanizates. shows. The vulcanization method was press vulcanization. Examples 1 to 6 These are experimental examples included in the scope of the invention. Compared to the vulcanizates of Comparative Examples 9 and 10 containing only CR, the cold resistance, weather resistance, oil resistance, heat resistance, vibration damping properties, fatigue properties, and tear strength are significantly improved. Comparative Examples 1 and 2 Controlled amount of polyether polyol (5 to 100
This is an example of deviation from the weight part). When the amount is insufficient (Comparative Example 1), there is almost no reforming effect, and when the amount is excessive (Comparative Example 2), the properties of chloroprene are lost, such as thermal softening deterioration, etc. ,
Tear strength, heat resistance, oil resistance, and fatigue properties are not sufficiently improved. Comparative Example 3 Regulated amount of low molecular weight polyol (0 to 15 parts by weight) and regulated range of t _B (0.9 t _A ≦ t _B ≦ 1.1 t _A ) in the case of the composition of Component A/Component B of the invention This is an example that deviates from both. Not only is the modification effect insufficient, but fatigue properties and cold resistance tend to deteriorate. Comparative Examples 4, 5, and 6 These are examples of compositions of component A/component B of the invention in which t _C deviates from the regulatory range (0.9t _A ≦t _C ≦1.1t _A ). When the lower limit is exceeded (Comparative Example 6), most of the modification effects are not sufficient, and when the upper limit is exceeded (Comparative Examples 7 and 9), the modification effects other than weather resistance are not sufficient. Tend. Comparative Example 7 This is an example in which the composition of component A/component B of the invention deviates from the regulatory range of t _B (0.9t _A ≦t _B ≦1.1t _A ). Modification effect is insufficient. Comparative Example 8 This is an example in which the amount of low molecular weight polyisocyanate deviates from the regulation amount (0 to 10 parts by weight) in the case of the composition of component A/component C of the invention. Not only is the modification effect insufficient, but the fatigue properties and cold resistance tend to deteriorate.

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【table】 [Brief explanation of drawings]

Figure 1 shows Table 1 of Examples, formulation No. A-1, and temperature.
This is a diagram showing the relationship between time and torsional moment when the temperature is 140°C, and FIG. 2 is a diagram showing the relationship between time obtained from FIG. 1 and the first-order differential coefficient of torsional moment.

Claims (1)

[Scope of Claims] 1. Component A containing 100 parts by weight of chloroprene rubber and a vulcanizing agent for chloroprene rubber. 5 to 100 parts by weight of polyester polyol or polyether polyol, 0 parts of low molecular weight polyol
Component B comprising ~15 parts by weight and polyisocyanate. 2 isocyanate groups in one molecule as functional groups
Component C, which contains 5 to 100 parts by weight of a prepolymer having at least 100% polyisocyanate, 0 to 10 parts by weight of a low molecular weight polyisocyanate, and one or more compounds selected from the group consisting of polyamines, polyols, polycarboxylic acids, and water. Consists of a combination of the above components A and B, or components A and C, at any temperature (temperature T)
Let _tA be the time required for the first-order differential coefficient of the rising curve of the torsional moment of component A to reach its maximum at tA, and separately from this, the first-order differential curve of the rising curve of the torsional moment of only component B or component C at temperature T. A chloroprene rubber composition characterized in that the maximum times are in the range of 0.9t _A ≦t _B ≦1.1t _A and 0.9t _A ≦t _C ≦1.1t _A , where t _B and t _C respectively. 2 The chloroprene rubber in component A contains 50 to 100 parts by weight of 2-chloro-1,3-butadiene, 1-chloro-1,3-butadiene, 2,3-dichloro-
A polymer obtained by radical polymerization of 0 to 50 parts by weight of one or more monomers selected from the group consisting of 1,3-butadiene, methyl methacrylate, methyl acrylate, methacrylic acid, acrylic acid, styrene, and acrylonitrile. The chloroprene rubber composition according to claim 1, characterized in that: 3. Claim No. 3, characterized in that the isocyanate group contained in one or more compounds in component B and component C is a blocked isocyanate group that has been preliminarily reacted with a phenol compound or an oxime compound. The chloroprene rubber composition according to item 1.