JP2009235178A - Composition for rubber glove, and rubber glove - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composition for a rubber glove for manufacturing the rubber glove having excellent tear strength. <P>SOLUTION: The composition for the rubber glove comprises a copolymer (C) obtained by polymerizing a monomer component (B) including at least one selected from the group consisting of an unsaturated nitrile monomer (b-1), a (meth)acrylic acid based monomer (b-2) and an aromatic vinyl monomer (b-3) in the presence of an unsaturated nitrile-a conjugated diene based copolymer (A) obtained by polymerizing at least an unsaturated nitrile monomer (a-1) and a conjugated diene monomer (a-2). In the composition for the rubber glove, an α value represented by formula (1) in the copolymer (C) is 1.0 or less. α=[tanδ(150°C)-tanδ(60°C)]/tanδ(60°C)..(1). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rubber glove composition and a rubber glove. More specifically, the present invention relates to a rubber glove composition capable of producing a rubber glove having excellent stability and high tear strength, and a rubber glove formed using such a rubber glove composition.

  Rubber gloves are used in a wide range of applications such as housework, food-related industry, precision industry, and medical care. In particular, rubber gloves using acrylonitrile butadiene rubber (hereinafter sometimes referred to as “NBR”) are more resistant to chemicals and oil than rubber gloves using natural rubber and gloves using vinyl chloride resin. Since it is excellent in wear resistance and the like, it is suitably used during various operations (see, for example, Patent Documents 1 to 7).

JP 2001-303329 A JP 2001-049511 A JP 2002-309043 A JP 2004-131885 A JP 2006-321955 A JP-A-11-302911 Japanese Patent Laid-Open No. 05-247266

  NBR rubber gloves having such chemical resistance are required to have high tear strength from the viewpoint of safety during use.

  However, the above-mentioned conventional rubber gloves are not sufficient in tearing strength, and for example, when they are stretched strongly when worn or when they are caught on a pointed object during use, they are easily broken. was there.

  As means for increasing the tear strength of such NBR rubber gloves, the content of acrylonitrile contained in the composition for forming rubber gloves (hereinafter sometimes referred to as “composition for rubber gloves”) (Hereinafter, sometimes referred to as “AN content ratio”) is increased, but if this AN content ratio is increased, the stability of the emulsion (latex) obtained at the end of the polymerization reaction is reduced, and rubber gloves There is a problem that it becomes difficult to manufacture, specifically, molding of rubber gloves. Moreover, when a rubber glove is manufactured using the latex which such stability fell, there also existed a problem that the quality of the rubber glove obtained fell.

  Thus, in the conventional rubber glove composition, there is a tradeoff between increasing the tear strength of the obtained rubber glove and improving the stability of the latex to facilitate the production of the rubber glove. Therefore, it was extremely difficult to achieve both.

  The present invention has been made in view of such problems of the prior art, and the object of the present invention is to provide a rubber glove composition that is excellent in stability and has a high tear strength. And the rubber glove excellent in tear strength formed using such a composition for rubber gloves is provided.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors use a composition containing a copolymer having a loss coefficient (tan δ) at 60 ° C. and 150 ° C. satisfying a specific relationship as a composition for rubber gloves. As a result, the present inventors have found that the above-described problems can be achieved, and have completed the present invention.

  That is, according to this invention, the composition for rubber gloves shown below and a rubber glove are provided.

[1] In the presence of (A) an unsaturated nitrile / conjugated diene copolymer obtained by polymerizing at least (a-1) an unsaturated nitrile monomer and (a-2) a conjugated diene monomer, (B-1) includes at least one selected from the group consisting of unsaturated nitrile monomers, (b-2) (meth) acrylic acid monomers, and (b-3) aromatic vinyl monomers. (B) It contains a copolymer (C) obtained by polymerizing monomer components, and the value of α represented by the following formula (1) of the (C) copolymer is 1.0 or less. A composition for rubber gloves.

  α = [tan δ (150 ° C.) − tan δ (60 ° C.)] / tan δ (60 ° C.) (1)

  In the formula (1), tan δ (150 ° C.) represents the loss coefficient of the (C) copolymer at 150 ° C., and tan δ (60 ° C.) represents the loss coefficient of the (C) copolymer at 60 ° C. Indicates.

[2] The (C) copolymer is prepared by adding the monomer component (B) to the aqueous dispersion of the (A) unsaturated nitrile / conjugated diene copolymer, and The rubber glove composition according to the above [1], which is polymerized in a state where the ratio of the conjugated diene monomer to the monomer is 10 mol% or less.

[3] The rubber glove according to [1] or [2], wherein the (b-1) unsaturated nitrile monomer is acrylonitrile and the (b-3) aromatic vinyl monomer is styrene. Composition.

[4] The (C) copolymer comprises 20 to 98 parts by mass of the (A) unsaturated nitrile / conjugated diene copolymer and 2 to 80 parts by mass of the (B) monomer component (provided that ( A) + (B) = 100 parts by mass), and the composition for rubber gloves according to any one of [1] to [3].

[5] The (a-1) unsaturated nitrile monomer is acrylonitrile, the (a-2) conjugated diene monomer is butadiene, and the (A) unsaturated nitrile / conjugated diene copolymer The coalescence is 10 to 60% by mass of the structural unit (i) derived from the (a-1) unsaturated nitrile monomer, and the structural unit (ii) derived from the (a-2) conjugated diene monomer. 10 to 90% by mass, and (a-3) 0 to 80% by mass of the structural unit (iii) derived from other monomers (provided that (i) + (ii) + (iii) = 100% by mass) The composition for rubber gloves according to any one of [1] to [4], wherein

[6] The rubber glove composition according to any one of [1] to [5], further including a crosslinking agent.

[7] A rubber glove obtained by crosslinking the rubber glove composition according to any one of [1] to [6].

  Since the composition for rubber gloves of the present invention is excellent in stability, it is easy to form a rubber glove and can be a high quality rubber glove. Moreover, this rubber glove composition can form a rubber glove having high tear strength.

  The rubber glove of the present invention is formed from the above-described rubber glove composition and has a high tear strength.

  BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out the present invention will be described below, but the present invention is not limited to the following embodiment, and is based on the ordinary knowledge of those skilled in the art without departing from the gist of the present invention. It should be understood that modifications and improvements as appropriate to the following embodiments also fall within the scope of the present invention.

1. Rubber gloves composition:
One embodiment of the rubber glove composition of the present invention is obtained by polymerizing at least (a-1) an unsaturated nitrile monomer and (a-2) a conjugated diene monomer. (A) Unsaturation In the presence of a nitrile / conjugated diene copolymer, (b-1) an unsaturated nitrile monomer, (b-2) a (meth) acrylic acid monomer, and (b-3) an aromatic vinyl monomer It is a composition containing (C) copolymer obtained by polymerizing the monomer component (B) containing at least 1 type selected from the group which consists of a body.

  And this rubber glove composition WHEREIN: The value of (alpha) represented by following formula (1) of the said (C) copolymer is 1.0 or less.

  α = [tan δ (150 ° C.) − tan δ (60 ° C.)] / tan δ (60 ° C.) (1)

  In the formula (1), tan δ (150 ° C.) indicates a loss coefficient at 150 ° C., and tan δ (60 ° C.) indicates a loss coefficient at 60 ° C.

  The rubber glove composition of this embodiment can be used to form rubber gloves that can be used in a wide range of applications such as housework, food-related industry, precision industry, and medical care. It is suitable for use in forming rubber gloves with high tear strength used for work such as cleaning, precision work in a clean room, and medical (surgery) operations such as surgery and treatment in the medical field. it can.

1A. (A) Unsaturated nitrile / conjugated diene copolymer:
(A) Unsaturated nitrile / conjugated diene copolymer (hereinafter also referred to as “component (A)”) includes at least (a-1) an unsaturated nitrile monomer and (a-2) a conjugated diene monomer. (A-1) a structural unit derived from an unsaturated nitrile monomer (i) and (a-2) a structural unit derived from a conjugated diene monomer ( and ii). The (C) copolymer described above is a copolymer obtained by modifying the (A) unsaturated nitrile / conjugated diene copolymer with the monomer component (B). By using such a component (A), excellent rubber elasticity and flexibility are imparted to the resulting rubber glove.

1A-1. (A-1) Unsaturated nitrile monomer:
The term “unsaturated nitrile monomer” as used herein refers to a compound having a polymerizable double bond and a nitrile group (cyano group) in one molecule.

  (A-1) Specific examples of the unsaturated nitrile monomer include (meth) acrylonitriles such as acrylonitrile, methacrylonitrile, α-ethylacrylonitrile, methyl α-isopropylacrylonitrile, methyl α-n-butylacrylonitrile; 2 -Cyanoethyl (meth) acrylate, 2- (2-cyanoethoxy) ethyl (meth) acrylate, 3- (2-cyanoethoxy) propyl (meth) acrylate, 4- (2-cyanoethoxy) butyl (meth) acrylate, 2 In addition to cyano group-containing (meth) acrylic esters such as-[2- (2-cyanoethoxy) ethoxy] ethyl (meth) acrylate, fumaronitrile, 2-methyleneglutaronitrile, and the like can be given.

  (A-1) Although there is no restriction | limiting in particular about the kind of unsaturated nitrile monomer, Acrylonitrile is preferable. The component (A) may be a copolymer containing only one type of structural unit (i) derived from the (a-1) unsaturated nitrile monomer, or two or more types of structural units (i ).

1A-2. (A-2) Conjugated diene monomer:
As used herein, “conjugated diene monomer” refers to a compound including a structure in which two carbon-carbon double bonds are connected by one carbon-carbon single bond. (A-2) Specific examples of the conjugated diene monomer include 1,3-butadiene, isoprene (2-methyl-1,3-butadiene), 2,3-dimethyl-1,3-butadiene, and chloroprene (2 -Chloro-1,3-butadiene) and the like.

  (A-2) Although there is no restriction | limiting in particular about the kind of conjugated diene monomer, 1,3-butadiene, isoprene and 1,3-pentadiene are preferable and 1,3-butadiene and isoprene are more preferable. The component (A) may be a copolymer containing only one type of structural unit (ii) derived from the (a-2) conjugated diene monomer, or two or more types of structural units (ii). It may be a copolymer containing

1A-3. (A-3) Other monomers:
The component (A) comprises (a-1) an unsaturated nitrile monomer and (a-2) a structural unit (iii) derived from other monomers other than the conjugated diene monomer (a-3). It may be included. This (a-3) other monomer has a polymerizable double bond and can be copolymerized with (a-1) an unsaturated nitrile monomer and (a-2) a conjugated diene monomer. If it is.

  Specific examples of such (a-3) other monomers include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-tert-butylstyrene, o- Examples thereof include aromatic vinyl compounds such as methoxystyrene, m-methoxystyrene, and p-methoxystyrene; (b-2) (meth) acrylic acid monomers described later. The component (A) may be a copolymer containing only (a-3) one type of structural unit (iii) derived from another monomer, or two or more types of structural units (iii). It may be a copolymer containing

  In the case where the component (A) is composed of only the structural unit (i) and the structural unit (ii), the content ratio of the structural unit (i) in all the structural units is 10 to 60% by mass. Preferably, it is 10-55 mass%. When the content ratio of the structural unit (i) is 10% by mass or more, chemical resistance can be imparted to the resulting rubber glove. On the other hand, when the content of the structural unit (i) is 60% by mass or less, the proportion of the structural unit (ii) is increased correspondingly, and flexibility can be imparted to the resulting rubber glove.

  Moreover, when (A) component is comprised only by the structural unit (i) and the structural unit (ii), the content rate of the structural unit (ii) in all the structural units is 40-90 mass%. It is preferably 50 to 90% by mass, more preferably 50 to 85% by mass. By setting the content ratio of the structural unit (ii) to 40% by mass or more, flexibility can be imparted to the obtained rubber glove. Moreover, if the content rate of structural unit (ii) shall be 90 mass% or less, the content rate of structural unit (i) will increase correspondingly, and chemical resistance can be provided to the rubber glove obtained. .

  Thus, when the component (A) is composed only of the structural unit (i) and the structural unit (ii), (a-1) acrylonitrile as the unsaturated nitrile monomer, and (a-2) a conjugated diene unit. It is preferable to select butadiene as the monomer. That is, the component (A) is preferably acrylonitrile-butadiene rubber (NBR).

  In the case where the component (A) includes the structural unit (iii) in addition to the structural unit (i) and the structural unit (ii), the content ratio of the structural unit (iii) in all the structural units is 80% by mass or less is preferable. When the content ratio of the structural unit (iii) is 80% by mass or less, the properties derived from the structural unit (iii) can be imparted without deteriorating the workability of the rubber glove composition.

  In the case where the component (A) includes the structural unit (iii) in addition to the structural unit (i) and the structural unit (ii), the structure in all the structural units is used from the viewpoint of chemical resistance. The content ratio of the unit (i) is preferably 10 to 60% by mass, and more preferably 10 to 55% by mass. Moreover, it is preferable that the content rate of the structural unit (ii) in all the structural units is 10-90 mass%, and it is still more preferable that it is 10-80 mass%.

  Thus, when (A) component is comprised by structural unit (i), structural unit (ii), and structural unit (iii), (a-1) acrylonitrile as an unsaturated nitrile monomer, (a -2) It is preferable to select butadiene as the conjugated diene monomer and (a-3) (meth) acrylic acid ester as the other monomer. That is, the component (A) is preferably acrylonitrile / butadiene / (meth) acrylate rubber.

1A-4. (A) Preparation of unsaturated nitrile / conjugated diene copolymer:
Component (A) is, for example, polymerized (a-1) unsaturated nitrile monomer, (a-2) conjugated diene monomer, and (a-3) other monomer as required. Can be prepared. There is no restriction | limiting in particular about the polymerization reaction at the time of preparing this (A) component, A conventionally well-known polymerization method is employable. For example, radical polymerization, cationic polymerization, anionic polymerization and the like can be mentioned, and radical polymerization prepared by copolymerization in the presence of a radical polymerization initiator is particularly preferable. Hereinafter, the method for preparing the component (A) will be specifically described by taking radical polymerization as an example.

  As radical polymerization initiators used for radical polymerization, azo compounds such as azobisisobutyronitrile; benzoyl peroxide, lauroyl peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, paramentane hydroperoxide, di- organic peroxides such as tert-butyl peroxide and dicumyl peroxide; inorganic peroxides such as potassium persulfate; redox catalysts combining the peroxide and a reducing agent (such as ferrous sulfate) Can be mentioned. These radical polymerization initiators can be used singly or in combination of two or more.

  It is preferable that the usage-amount of a radical polymerization initiator shall be 0.001-2 mass parts with respect to 100 mass parts of whole quantity of a monomer. As the polymerization method, known methods such as bulk polymerization, solution polymerization, suspension polymerization, and emulsion polymerization can be employed. Of these, emulsion polymerization is particularly preferred.

  Examples of the emulsifier used in the emulsion polymerization include an anionic surfactant, a nonionic surfactant, a cationic surfactant, an amphoteric surfactant, and the like, and a fluorine-based surfactant may be used. . Among the emulsifiers, an anionic surfactant can be preferably used. More specifically, it is preferable to use a sulfonate, a long-chain fatty acid salt having 10 or more carbon atoms, a rosinate, and the like. Among these salts, a potassium salt, a sodium salt, or a combination thereof is used. Further preferred. Other emulsifiers can be used alone or in combination of two or more.

  In the polymerization, a chain transfer agent can also be used to adjust the molecular weight of the component (A) to be obtained. Examples of the chain transfer agent include alkyl mercaptans such as tert-dodecyl mercaptan and n-dodecyl mercaptan, carbon tetrachloride, thioglycols, diterpenes, terpinolene, and γ-terpinenes.

  (A-1) Monomers such as unsaturated nitrile monomers and (a-2) conjugated diene monomers, emulsifiers, radical polymerization initiators, chain transfer agents, etc. are charged all at once into the reaction vessel. Then, the polymerization may be started, or may be added continuously or intermittently while the reaction is continued. The polymerization method may be a continuous method or a batch method. The polymerization reaction is preferably performed using a reactor from which oxygen is removed. The polymerization reaction temperature is preferably 0 to 100 ° C, and more preferably 0 to 80 ° C. During the polymerization reaction, the raw material addition method, temperature, conditions such as stirring, and the like may be appropriately changed.

  The polymerization reaction time is usually about 0.01 to 30 hours. The polymerization reaction can be stopped by adding a polymerization terminator when a predetermined polymerization conversion rate is reached. Examples of the polymerization terminator include amine compounds such as hydroxylamine and N, N-diethylhydroxylamine; quinone compounds such as hydroquinone.

  After the polymerization reaction is stopped, the unreacted monomer can be removed from the resulting emulsion (latex) by a method such as steam distillation as necessary to obtain the desired component (A).

  In addition, when the (B) monomer component is polymerized in the presence of the (A) component to modify the (A) component, it can be performed in an aqueous dispersion of the (A) component. . Accordingly, the emulsion (latex) of the component (A) described above can be used as it is as the component (A).

1B. (B) Monomer component:
The monomer component (B) is a monomer component for modifying the component (A) into a copolymer (C). This (B) monomer component (hereinafter also referred to as “(B) component”) includes (b-1) an unsaturated nitrile monomer, (b-2) a (meth) acrylic acid monomer, And (b-3) at least one selected from the group consisting of aromatic vinyl monomers. In addition, (B) monomer component includes the above-mentioned (b-1) unsaturated nitrile monomer, (b-2) (meth) acrylic acid monomer, and (b-3) aromatic vinyl. Other than the monomers, (b-4) other monomers copolymerizable with these monomers may further be included.

1B-1. (B-1) Unsaturated nitrile monomer:
Specific examples of the (b-1) unsaturated nitrile monomer include those similar to the specific examples of the “(a-1) unsaturated nitrile monomer” exemplified above. Of these, acrylonitrile is preferable.

1B-2. (B-2) (Meth) acrylic acid monomer:
(B-2) Specific examples of (meth) acrylic acid monomers include (meth) acrylic acid and alcohol esters ((meth) acrylic acid esters). “(Meth) acrylic acid” means “acrylic acid or methacrylic acid”. Specific examples of this (meth) acrylic acid ester are shown below.

  Methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, sec-butyl (meth) Acrylate, t-butyl (meth) acrylate, n-amyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, lauryl (meth) acrylate, stearyl ( Alkyl (meth) acrylates such as (meth) acrylate;

  2,2,2-trifluoroethyl (meth) acrylate, 3,3,3,2,2-pentafluoropropyl (meth) acrylate, 4,4,4,3,3,2,2-heptafluorobutyl ( Fluoroalkyl (meth) acrylates such as (meth) acrylate;

  2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-methoxypropyl (meth) acrylate, 2-ethoxypropyl (meth) acrylate, 3-methoxypropyl (meth) acrylate, 3-ethoxypropyl ( Alkoxyalkyl (meth) acrylates such as (meth) acrylate;

  (Meth) acrylates of alkoxypolyalkylene glycols (number of alkylene glycol units: about 2 to 23) such as methoxypolyethylene glycol, ethoxypolyethylene glycol, methoxypolypropylene glycol, ethoxypolypropylene glycol; 2-phenoxyethyl (meth) acrylate, 2- Aryloxyalkyl (meth) acrylates such as phenoxypropyl (meth) acrylate and 3-phenoxypropyl (meth) acrylate;

  Mono (meth) acrylates of aryloxypolyalkylene glycol (number of alkylene glycol units: usually 2 to 23) such as phenoxy polyethylene glycol and phenoxy polypropylene glycol; 2-cyanoethyl (meth) acrylate, 2-cyanopropyl (meth) acrylate, Cyanoalkyl (meth) acrylates such as 3-cyanopropyl (meth) acrylate; ethylene glycol, 1,2-propanediol, 1,3-propanediol, 3-chloro-1,2-propanediol, 1,2- Mono- (meth) acrylates or di- (meth) acrylates of alkylene glycols such as butanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol ;

  Mono- or di- (meth) acrylates of polyalkylene glycols (number of alkylene glycol units: usually 2 to 23) such as polyethylene glycol and polypropylene glycol; glycerin, 1,2,4-butanetriol, pentaerythritol, trimethylolalkane Mono- or oligo- (meth) acrylates of trihydric or higher polyhydric alcohols such as (alkane carbon number: usually 1 to 3), tetramethylolalkane (alkane carbon number: usually 1 to 3); Mono- (meth) acrylates or oligo- (meth) acrylates of polyalkylene glycol adducts of polyhydric alcohols having a valence or higher (number of alkylene glycol units: usually 2 to 23);

  Mono- (meth) acrylates or oligo- (meth) acrylates of cyclic polyols such as 4-cyclohexanediol, 1,4-benzenediol, 1,4-di- (2-hydroxyethyl) benzene; dimethylaminomethyl (Meth) acrylate, diethylaminomethyl (meth) acrylate, 2-dimethylaminoethyl (meth) acrylate, 2-diethylaminoethyl (meth) acrylate, 2-dimethylaminopropyl (meth) acrylate, 2-diethylaminopropyl (meth) acrylate, 2- (di-n-propylamino) propyl (meth) acrylate, 3-dimethylaminopropyl (meth) acrylate, 3-diethylaminopropyl (meth) acrylate, 3- (di-n-propylamino) propyl (meth) acrylate Dialkylaminoalkyl (meth) acrylate and the like;

  Esterified carboxyl groups such as (dialkylaminoalkoxy) alkyl (meth) acrylates such as 2- (dimethylaminoethoxy) ethyl (meth) acrylate and 2- (diethylaminoethoxy) ethyl (meth) acrylate; lactone modification (Meth) acrylate.

  Especially, the alkoxy alkyl (meth) acrylate which has a C1-C4 alkoxy group, a C2-C6 alkyl (meth) acrylate is preferable, and a C2-C6 alkyl (meth) acrylate is still more preferable. These (b-2) (meth) acrylic acid monomers can be used singly or in combination of two or more.

1B-3. (B-3) Aromatic vinyl monomer:
(B-3) Specific examples of the aromatic vinyl monomer include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-tert-butylstyrene, and o-methoxystyrene. , M-methoxystyrene, p-methoxystyrene and the like. Of these, styrene is preferable. These (b-3) aromatic vinyl monomers can be used singly or in combination of two or more. In addition, it is preferable to use acrylonitrile as the (b-1) unsaturated nitrile monomer and to use styrene as the (b-3) aromatic vinyl monomer.

1C. (C) Copolymer:
The (C) copolymer is a copolymer obtained by polymerizing the (B) component in the presence of the (A) component. This (C) copolymer has a value of α represented by the above formula (1) of 1.0 or less. In addition, the value of α indicates a measured value in solid rubber. Specifically, in the presence of the component (A), the component (A) and the component (B) are polymerized, and then sodium chloride Salt in calcium chloride, potassium chloride, etc .; acid in hydrochloric acid, nitric acid, sulfuric acid etc. is added to coagulate the copolymer, and then the copolymer is washed and dried to obtain α in the copolymer. Is a value of 1.0 or less.

  Thus, when the value of α is 1.0 or less, the stability of the latex can be improved, and the tear strength of the resulting rubber glove can be increased. Note that the value of α is more preferably 0.8 or less, and particularly preferably 0.6 or less. Moreover, the lower limit of the value of α is not particularly limited. The rubber glove composition containing such a copolymer (C) can reduce deformation during vulcanization in a glove shape. That is, since the shape retention is good, it is possible to form an extremely thin glove.

1C-1. (C) Preparation method of copolymer:
Such a copolymer (C) is obtained by emulsion polymerization of the component (A), for example, (a-1) an unsaturated nitrile monomer and (a-2) a conjugated diene monomer ( It can be obtained by adding the component (B) to the emulsion (latex A) of component A) and polymerizing it (hereinafter also referred to as “reforming reaction”). In addition, as this latex A, what removed the unreacted monomer by steam distillation etc. may be used, and what has not removed the unreacted monomer (with the unreacted monomer remaining) May be used.

  This modification reaction includes, for example, radical polymerization, cationic polymerization, anionic polymerization and the like. Examples of the modification method include bulk polymerization, solution polymerization, suspension polymerization, and emulsion polymerization.

  When this reforming reaction is performed, the ratio of the conjugated diene monomer to the total monomer existing in the system is 10 mol% or less with the component (B) added to the component (A). It is preferable to carry out the reforming reaction in such a state, and it is more preferable to carry out the reforming reaction in a state of 5 mol% or less. When this ratio exceeds 10 mol%, the modification of the component (A) becomes insufficient, and the value of α of the (C) copolymer may exceed 1.0. In addition, the ratio of the conjugated diene monomer to the total monomer existing in the system (within the reaction system) is, for example, that of the unreacted conjugated diene monomer in the emulsion (latex A) at the end of the emulsion polymerization reaction. It can be calculated from the residual amount and the amount of the conjugated diene monomer contained in the component (B) added to the emulsion.

  Here, the “all monomers present in the system” include, in addition to the component (B) added to the component (A), unreacted monomers remaining in the system of the component (A). Including. By precisely controlling the ratio of the conjugated diene monomer during the modification reaction in this way, the stability of the emulsion (latex B) obtained at the end of the modification reaction to obtain the (C) copolymer is improved. Can be improved.

  As described above, in order to control the ratio of the conjugated diene monomer to 10 mol% or less, for example, from the emulsion (latex A) of the component (A) obtained by emulsion polymerization, steam distillation or the like The method of removing an unreacted monomer by the method of can be mentioned. Thus, by reducing the amount of unreacted conjugated diene monomer in component (A), the amount of conjugated diene monomer is controlled to 10 mol% or less when component (A) is added. be able to.

  The (C) copolymer is obtained by polymerizing 20 to 98 parts by mass of the component (A) and 2 to 80 parts by mass of the component (B) (however, (A) + (B) = 100 parts by mass). Preferably, it is a polymer of 50 to 95 parts by mass of component (A) and 5 to 50 parts by mass of component (B) (provided that (A) + (B) = 100 parts by mass). Further preferred. (B) By setting a component to 2 mass parts or more, it can be set as the rubber glove comprised from the rubber | gum of the intensity | strength (specifically tear strength) to anticipate. On the other hand, the stability of latex B can be maintained by setting it as 80 mass parts or less.

  The reaction of the component (A) and the component (B) can be performed by ordinary emulsion polymerization, and is preferably performed in a reactor from which oxygen has been removed under a temperature condition of 0 to 50 ° C. The polymerization method may be either a continuous type or a batch type. Monomers, emulsifiers, initiators, molecular weight regulators and other polymerization agents may be added in total before the start of the reaction, or may be arbitrarily added after the start of the reaction. The operation conditions can be arbitrarily changed.

  As described above, the (C) copolymer obtained by modifying the copolymer as the (A) component with the (B) component can be prepared. In addition, the (C) copolymer constituting the rubber glove composition of the present invention has a value of α represented by the above formula (1) of 1.0 or less. The ratio of the monomer is controlled to 10 mol% or less so that the α value of the obtained (C) copolymer is 1.0 or less.

  In this specification, loss factors at 60 ° C. and 150 ° C. (tan δ (60 ° C.) and tan δ (150 ° C.)) are measured on a copolymer (raw rubber, uncrosslinked rubber), frequency 10 Hz, strain 5.02 % Is a value measured at each temperature using a predetermined rubber processability analyzer. The tan δ can be measured under the above conditions using, for example, a rubber processability analyzer (trade name “RPA2000”) manufactured by Alpha Technologies.

(C) The Mooney viscosity (ML _{1 + 4} , 100 ° C.) of the copolymer is preferably 10 to 200, and more preferably 20 to 200. By setting the Mooney viscosity to 10 or more, sufficient strength can be imparted to the rubber composition obtained using this (C) copolymer. On the other hand, by setting the Mooney viscosity to 200 or less, a rubber composition obtained by immersing a glove mold in the rubber glove composition of the present invention, and then pulling up the soaked mold, drying, and vulcanizing. A rubber glove having a uniform and beautiful appearance can be obtained.

  In the rubber glove composition of the present invention, the (C) copolymer preferably contains a crosslinking agent, a crosslinking aid and the like. By comprising in this way, it can be set as the material for rubber gloves with high intensity | strength.

1D. (D) Other polymer components:
The composition for rubber gloves of the present invention may contain (D) another polymer component (hereinafter also referred to as “component (D)”). Specific examples of the component (D) include natural rubber, butadiene rubber, isoprene rubber, chloroprene rubber, styrene / butadiene copolymer rubber, butadiene / isoprene copolymer rubber, butadiene / styrene / isoprene copolymer rubber, and acrylonitrile. -Butadiene copolymer rubber, acrylic rubber, butyl rubber, etc. can be mentioned. (D) It is preferable that the content rate of a component is 0-30 mass parts with respect to 100 mass parts of compositions for rubber gloves, and it is still more preferable that it is 0-10 mass parts.

1E. (E) Additive:
Examples of the (E) additive that can be contained in the rubber glove composition of the present invention include a crosslinking agent, a reinforcing agent, a thickener, and a plasticizer. In addition, these additives may be contained individually by 1 type, and may be contained in combination of 2 or more types. Moreover, as this (E) additive, you may use a pigment, a ultraviolet absorber, an anti-aging agent, a flame retardant, antibacterial and antifungal agent, etc.

1E-1. Cross-linking agent:
Examples of the crosslinking agent include crosslinking agents (vulcanizing agents) generally used for rubber crosslinking (vulcanization). Specific examples of the crosslinking agent include sulfur and organic peroxides, among which sulfur is preferable. Specific examples of sulfur include powdered sulfur, precipitated sulfur, colloidal sulfur, surface-treated sulfur, insoluble sulfur and the like.

  In addition, when using sulfur as a crosslinking agent, it is preferable that the compounding quantity of sulfur is 0.05-5 mass parts with respect to 100 mass parts of (C) copolymers, 0.1-3 mass parts More preferably. By setting the crosslinking agent to 0.05 parts by mass or more, a preferable effect of high strength can be obtained. On the other hand, deterioration of the workability of the rubber obtained by setting it as 5 mass parts or less can be suppressed.

  In addition, when sulfur is used as the crosslinking agent, it is preferable to use a crosslinking aid (hereinafter also referred to as “vulcanization accelerator”) in combination.

  Examples of the vulcanization accelerator include N-cyclohexyl-2-benzothiazolylsulfenamide, N-oxydiethylene-2-benzothiazolylsulfenamide, N, N-diisopropyl-2-benzothiazolylsulfen Sulfenamide compounds such as amides; thiazoles such as 2-mercaptobenzothiazole, 2- (2 ′, 4′-dinitrophenyl) mercaptobenzothiazole, 2- (4′-morpholinodithio) benzothiazole, dibenzothiazyl disulfide Compounds;

  Guanidine compounds such as diphenylguanidine, diorthotolylguanidine, diorthonitrile guanidine, orthonitrile biguanide, diphenylguanidine phthalate; acetaldehyde-aniline reactant, butyraldehyde-aniline condensate, aldehyde amine such as hexamethylenetetramine, acetaldehyde ammonia Or an aldehyde-ammonia compound; an imidazoline compound such as 2-mercaptoimidazoline; a thiourea compound such as thiocarbanilide, diethylthiourea, dibutylthiourea, trimethylthiourea, diortholylthiourea; tetramethylthiuram monosulfide, tetramethyl Thiuram disulfide, tetraethyl thiuram disulfide, tetrabutyl thiuram disulfide, tetraoctyl Ulam disulfide, thiuram-based compounds such as pentamethylene thiuram tetrasulfide;

  Dithioacid salts such as zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc di-n-butyldithiocarbamate, zinc ethylphenyldithiocarbamate, zinc butylphenyldithiocarbamate, sodium dimethyldithiocarbamate, selenium dimethyldithiocarbamate, and tellurium dimethyldithiocarbamate Zanthate compounds such as zinc dibutylxanthate; inorganic zinc compounds such as zinc white, active zinc white, surface-treated zinc white, zinc carbonate, composite zinc white, composite active zinc white, and the like. These crosslinking agents can be used singly or in combination of two or more.

  Specific examples of the organic peroxide include t-butyl hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, p-menthane hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, di-t-butylperoxide, t-butylcumylper Oxide, dicumyl peroxide, 1,1-bis (t-butylperoxy) cyclododecane, 2,2-bis (t-butylperoxy) octane, 1,1-di-t-butylperoxycyclohexane, 2 , 5-dimethyl-2,5-di- (t-butylperoxy) hexane, 2, -Dimethyl-2,5-di- (t-butylperoxy) hexyne 1,3-bis (t-butylperoxy-isopropyl) benzene, 2,5-dimethyl-2,5-di- (benzoylperoxy) hexane Besides,

  1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-bis (t-butylperoxy) valerate, bazoyl peroxide, m-toluyl peroxide P-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, t-butylperoxyisobutyrate, t-butylperoxy-2-ethylhexanoate, t-butylperoxybenzoate, t-butylperoxide Examples thereof include oxy-isopropyl carbonate and t-butyl peroxyallyl carbonate. These organic peroxides can be used alone or in combination of two or more.

  When the organic peroxide is used as the crosslinking agent, the amount of the organic peroxide is preferably 0.2 to 5 parts by mass with respect to 100 parts by mass of the copolymer (C). More preferably, it is -4 mass parts. When the crosslinking agent is 0.2 parts by mass or more, high strength can be imparted to the resulting rubber (glove rubber). On the other hand, when the amount is 5 parts by mass or less, deterioration of workability of the obtained rubber (glove rubber) can be suppressed.

2. Rubber gloves:
Next, one embodiment of the rubber glove of the present invention will be specifically described. One embodiment of the rubber glove of the present invention is a rubber glove made of a rubber composition obtained by crosslinking the above-described rubber glove composition of the present invention. Thus, the rubber composition obtained by crosslinking the rubber glove composition containing the copolymer (C) is excellent in strength, particularly tear strength. For this reason, the rubber glove of this embodiment is a rubber glove having high strength and excellent rubber elasticity.

  The shape of the rubber glove of the present embodiment is not particularly limited. For example, as shown in FIG. 1, a hand covering portion 2 that covers the user's hand, and a wrist of the user that is molded integrally with the hand covering portion. The rubber glove 1 provided with the wrist covering part 4 to cover can be mentioned.

  Here, FIG. 1 is a plan view showing an embodiment of the rubber glove of the present invention. In addition, there is no restriction | limiting in particular about the magnitude | size etc. of a rubber glove, It can determine suitably according to a use purpose, the magnitude | size of a user's hand, etc.

  Further, the rubber glove of the present embodiment may be a left-right rubber glove that does not distinguish between left and right hands. For example, the left and right hands having unevenness such as non-slip on the palm side, etc. There may be rubber gloves.

  In the rubber glove of the present embodiment, for example, a rubber glove having a good fit at the time of use can be obtained by collecting an actual human hand mold and using it as a base for molding.

  The thickness of the rubber glove (that is, the thickness of the rubber film) is not particularly limited, and can be appropriately adjusted depending on the type of rubber glove and the purpose of use. For example, in the case of rubber gloves used for precision work, the thickness is preferably 0.1 mm or more, and more preferably 0.8 mm or less. If it is used for housework or chemical handling, the thickness is preferably 0.5 mm to 2 mm.

2-1. Manufacturing method of rubber gloves:
As a method for producing the rubber glove of the present invention, various conventionally known methods such as a direct method (direct dipping method), a heat-sensitive method (heat-sensitive coagulation method), and an anode adhesion method can be employed. Therefore, when producing rubber gloves, (C) latex compound (rubber) for forming gloves by blending the aforementioned various additives into the emulsion (latex) obtained at the end of the polymerization reaction to obtain a copolymer. Glove composition) is prepared.

  Next, the obtained latex compound is dipped with a preheated glove mold or a coagulant applied to the surface of the latex compound, and then the dipped mold is pulled up, dried and vulcanized. Rubber gloves made of the composition can be obtained.

  As the above-described glove mold, for example, a pottery or ceramic one can be used. The preheating temperature of the mold can be appropriately determined according to the heat-sensitive agent used and the quality of the rubber material. Specifically, the surface of the mold is preferably preheated at a temperature of 80 to 100 ° C, and more preferably preheated at a temperature of 85 to 95 ° C.

  The vulcanization conditions are not particularly limited and can be appropriately determined according to the quality of the heat-sensitive agent and the rubber material to be used. For example, the vulcanization is performed at 100 to 120 ° C. for about 30 to 90 minutes. preferable.

  Further, it is preferable that the above-described glove mold is once immersed in a coagulation liquid before being immersed in the latex compound. As this coagulating liquid, for example, a coagulating liquid used for forming a conventional rubber glove such as a 30% calcium nitrate methanol solution can be used.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples. In the examples and comparative examples, “parts” and “%” are based on mass unless otherwise specified. Moreover, the measuring method of various physical-property values and the evaluation method of various characteristics are shown below.

  [Content Ratio of Structural Unit Derived from Monomer Component]: A 0.25% calcium chloride aqueous solution was added to the latex after completion of polymerization (latex B) to coagulate the copolymer, thereby obtaining a coagulated product. The obtained solidified product was sufficiently washed with water, and then dried at about 90 ° C. for 3 hours to obtain a copolymer (C). The copolymer was measured as the content ratio of acrylonitrile units (AN content ratio) and the content ratio of styrene units (ST content ratio).

  The AN content ratio (%) was calculated from the nitrogen content measured by elemental analysis. The ST content (%) was measured by pyrolysis gas chromatography.

  [Tan δ]: A 0.25% calcium chloride aqueous solution was added to the latex after completion of polymerization (latex B) to coagulate the copolymer to obtain a coagulated product. The obtained solidified product was sufficiently washed with water, and then dried at about 90 ° C. for 3 hours to obtain a copolymer (C). Using a rubber processability analyzer (model number “RPA2000”, manufactured by Alpha Technologies), tan δ (tan δ (60) of (C) copolymer at 60 ° C. and 150 ° C. under conditions of frequency 10 Hz and strain 5.02%. ° C) and tan δ (150 ° C).

  [Value of α]: α was calculated from the value of tan δ (tan δ (60 ° C.) and tan δ (150 ° C.)) obtained by the measurement of tan δ according to the above formula (1).

  [Tear Strength Test]: A test piece of a dip-molded product punched with a dumbbell (JIS B type) was torn at a tear speed of 500 mm / min, and the tear strength just before the break was measured.

  [Latex stability]: After completion of the polymerization reaction, the latex (latex B) with less coagulum was defined as “stable”, and the one with frequent coagulation was defined as “unstable”.

Example 1
(A-1) 70 parts of acrylonitrile as an unsaturated nitrile monomer, (a-2) 30 parts of butadiene as a conjugated diene monomer, 4 parts of sodium lauryl sulfate (emulsifier), 0.2 part of potassium persulfate ( Polymerization initiator) and 200 parts of water were charged into a nitrogen-substituted stainless steel reactor and polymerized at 40 ° C.

  When the polymerization conversion rate reached approximately 60%, 0.5 part of N, N-diethylhydroxylamine was added to the reaction system to stop the reaction, and latex (latex A) was obtained (reaction time: 8 hours). .

  Steam was added to the obtained latex A, and the remaining monomer was distilled off. After nitrogen substitution, (b-1) 16.8 parts of acrylonitrile as an unsaturated nitrile monomer, (b-3) 8.4 parts of styrene as an aromatic vinyl monomer, and 0.2% potassium persulfate Part (polymerization initiator) was added and polymerized at 40 ° C. When the polymerization conversion rate reached approximately 60%, 0.5 part of N, N-diethylhydroxylamine was added to the reaction system to stop the reaction, and latex (latex B) was obtained (reaction time: 4 hours). . Table 1 shows the formulation of polymerized latexes A and B. Further, a 0.25% calcium chloride aqueous solution was added to latex B to coagulate the copolymer, thereby obtaining a coagulated product. The obtained solidified product was sufficiently washed with water and then dried at about 90 ° C. for 3 hours to obtain a copolymer (C). Table 2 shows the AN content, ST content, tan δ (60 ° C.), tan δ (150 ° C.), and α of the copolymer.

  In Example 1, the (C) copolymer has an AN content of 50%, an ST content of 10%, tan δ (60 ° C.) of 0.50, tan δ (150 ° C.) of 0.30, and α of −0. .4.

To latex B (100 parts of (C) copolymer) obtained by the above method, 1.2 parts of zinc oxide, 1 part of zinc di-n-butylthiocarbamate, 1 part of sulfur, 0.5 part of NH ₄ OH, 0.2 parts of KOH, 0.2 parts of surfactant (trade name “Demol”, manufactured by Kao), 0.15 parts of heat-sensitive agent (trade name “Coagulant WS”, manufactured by Bayer), pigment (trade name “ PSM5272 ", produced by Mikuni Dye Co., Ltd.) 0.3 parts, antifoaming agent (trade name" SM5512, "manufactured by Toray Dow Corning Silicone Co., Ltd.) 0.01 part, and thickener (trade name" A-7070 ", 0.14 part (manufactured by Toagosei Chemical Industry Co., Ltd.) was added to prepare a rubber glove composition (latex compound).

  Thereafter, a ceramic glove mold was prepared, and this glove mold was immersed in a methanol solution of 30% calcium nitrate and then immersed in the rubber glove composition. After the elapse of 30 seconds, the glove mold is pulled up, heat-treated at 80 ° C. × 30 min, 90 ° C. × 10 min, 130 ° C. × 20 min, reversed from the glove mold, and then the rubber glove composition is crosslinked. A rubber glove (Example 1) comprising the prepared rubber composition was produced.

The tear strength of the test piece cut out from the obtained rubber glove was 100 kg / cm ² . Moreover, latex B at the time of rubber glove manufacture had few coagulum and was excellent in latex stability.

(Example 2)
As shown in Table 1, (a-1) 46 parts of acrylonitrile as an unsaturated nitrile monomer, (a-2) 54 parts of butadiene as a conjugated diene monomer, 4 parts of sodium lauryl sulfate, potassium persulfate 0 .2 parts and 200 parts of water were charged into a stainless steel reactor purged with nitrogen and polymerized at 40.degree.

  When the polymerization conversion rate reached approximately 70%, 0.5 part of N, N-diethylhydroxylamine was added to the reaction system to stop the reaction, and latex (latex A) was obtained (reaction time: 8 hours). .

  Steam was added to the obtained latex A, and the remaining monomer was distilled off. After nitrogen substitution, (b-1) 19.5 parts of acrylonitrile as an unsaturated nitrile monomer, (b-3) 9.7 parts of styrene as an aromatic vinyl monomer, and 0.2% potassium persulfate Part was added and polymerized at 40 ° C. When the polymerization conversion rate reached approximately 60%, 0.5 part of N, N-diethylhydroxylamine was added to the reaction system to stop the reaction, and latex (latex B) was obtained (reaction time: 4 hours). . Table 2 shows the AN content, ST content, tan δ (60 ° C.), tan δ (150 ° C.), and α of the coagulated product ((C) copolymer) obtained by the same method as in Example 1.

  Further, rubber gloves were produced by the same method as in Example 1 using the obtained latex B. Table 2 shows the evaluation results of the tear strength and latex stability of the test pieces cut out from the rubber gloves.

(Example 3)
As shown in Table 1, (a-1) 70 parts of acrylonitrile as an unsaturated nitrile monomer, (a-2) 30 parts of butadiene as a conjugated diene monomer, 4 parts of sodium lauryl sulfate, potassium persulfate 0 .2 parts and 200 parts of water were charged into a stainless steel reactor purged with nitrogen and polymerized at 40.degree.

  When the polymerization conversion rate reached approximately 70%, 0.5 part of N, N-diethylhydroxylamine was added to the reaction system to stop the reaction, and latex (component (A)) was obtained (reaction time: 8). time).

  Steam was added to the obtained latex A to distill off the remaining monomer. After nitrogen substitution, (b-1) 13.5 parts of acrylonitrile as an unsaturated nitrile monomer, (b-3) 6.7 parts of styrene as an aromatic vinyl monomer, (b-4) other 5 parts of butadiene as a monomer and 0.2 part of potassium persulfate were added and polymerized at 40 ° C. When the polymerization conversion rate reached approximately 60%, 0.5 part of N, N-diethylhydroxylamine was added to the reaction system to stop the reaction, and latex (latex B) was obtained (reaction time: 4 hours). . Table 2 shows the AN content, ST content, tan δ (60 ° C.), tan δ (150 ° C.), and α of the coagulated product ((C) copolymer) obtained by the same method as in Example 1.

  Moreover, the glove was manufactured by the method similar to Example 1 using obtained latex B. FIG. Table 2 shows the evaluation results of the tear strength and latex stability of the test pieces cut out from the rubber gloves.

(Comparative Example 1)
70 parts of acrylonitrile, 30 parts of butadiene, 4 parts of sodium lauryl sulfate, 0.2 part of potassium persulfate, and 200 parts of water were charged into a nitrogen-substituted stainless steel reactor and polymerized at 40 ° C. When the polymerization conversion rate reached approximately 60%, 0.5 part of N, N-diethylhydroxylamine was added to the reaction system to stop the reaction, thereby obtaining a latex (reaction time: 8 hours). Table 1 shows the AN content, ST content, tan δ (60 ° C.), tan δ (150 ° C.), and α of the coagulated product ((C) copolymer) obtained by the same method as in Example 1.

  Further, rubber gloves were produced by the same method as in Example 1 using the obtained latex. Table 2 shows the evaluation results of the tear strength and latex stability of the test pieces cut out from the rubber gloves.

(Comparative Example 2)
80 parts of acrylonitrile, 20 parts of butadiene, 4 parts of sodium lauryl sulfate, 0.2 part of potassium persulfate, and 200 parts of water were charged into a nitrogen-substituted stainless steel reactor and polymerized at 40 ° C. When the polymerization conversion rate reached approximately 70%, 0.5 part of N, N-diethylhydroxylamine was added to the reaction system to stop the reaction, and latex was obtained (reaction time: 8 hours).

  In Comparative Example 2, coagulated material was frequently generated in the latex after completion of the reaction, and it was impossible to form a rubber glove. Table 1 shows the AN content, ST content, tan δ (60 ° C.), tan δ (150 ° C.), and α of the rubber coagulated with the calcium chloride aqueous solution including the coagulated product.

(result)
In the rubber glove of Comparative Example 1, the stability of the latex after the completion of the reaction was good (stable), but because the (B) monomer was not used, the tear strength was low when the rubber glove was used, For example, if it is strongly stretched at the time of wearing, or if it is caught on a pointed tip during use, it is easily broken.

  On the other hand, in Comparative Example 2, since the stability of the latex after the completion of the reaction was poor and unstable, it was impossible to form a rubber glove itself.

  In the rubber gloves of Examples 1 to 3, the stability of the latex after completion of the reaction was good (stable), and rubber gloves having excellent quality could be obtained. Furthermore, this rubber glove has high tear strength, and it was possible to obtain a good result that it was difficult to tear when worn or used.

  The rubber glove of the present invention can be used in a wide range of applications such as housework, food-related industry, precision industry, and medical care. It can be suitably used for medical purposes (for surgery) such as surgery and treatment at medical sites and for handling organic solvents. Moreover, the composition for rubber gloves of this invention can be used suitably in order to manufacture the above-mentioned rubber glove of this invention.

It is a top view which shows one Embodiment of the rubber glove of this invention.

Explanation of symbols

1: Rubber gloves, 2: Hand covering part, 4: Wrist covering part.

Claims (7)

In the presence of (A) an unsaturated nitrile / conjugated diene copolymer obtained by polymerizing at least (a-1) an unsaturated nitrile monomer and (a-2) a conjugated diene monomer,
(B-1) includes at least one selected from the group consisting of unsaturated nitrile monomers, (b-2) (meth) acrylic acid monomers, and (b-3) aromatic vinyl monomers. (B) containing a copolymer (C) obtained by polymerizing monomer components,
The composition for rubber gloves whose value of (alpha) represented by following formula (1) of the said (C) copolymer is 1.0 or less.
α = [tan δ (150 ° C.) − tan δ (60 ° C.)] / tan δ (60 ° C.) (1)
(In the formula (1), tan δ (150 ° C.) represents the loss coefficient of the (C) copolymer at 150 ° C., and tan δ (60 ° C.) represents the loss of the (C) copolymer at 60 ° C. (Indicates coefficient) The (C) copolymer is
To the aqueous dispersion of the (A) unsaturated nitrile / conjugated diene copolymer, the monomer component (B) is added, and the ratio of the conjugated diene monomer to the total monomers present in the system is as follows: The rubber glove composition according to claim 1, wherein the composition is polymerized in a state of 10 mol% or less.   The rubber glove composition according to claim 1 or 2, wherein the (b-1) unsaturated nitrile monomer is acrylonitrile and the (b-3) aromatic vinyl monomer is styrene.   The (C) copolymer comprises 20 to 98 parts by mass of the (A) unsaturated nitrile / conjugated diene copolymer and 2 to 80 parts by mass of the monomer component (B) (provided that (A) + The composition for rubber gloves according to any one of claims 1 to 3, wherein (B) = 100 parts by mass) is polymerized. The (a-1) unsaturated nitrile monomer is acrylonitrile, the (a-2) conjugated diene monomer is butadiene,
The (A) unsaturated nitrile / conjugated diene copolymer comprises 10 to 60% by mass of the structural unit (i) derived from the (a-1) unsaturated nitrile monomer, and the (a-2) conjugate. 10 to 90% by mass of the structural unit (ii) derived from a diene monomer, and (a-3) 0 to 80% by mass of the structural unit (iii) derived from another monomer (provided that (i) + (Ii) + (iii) = 100% by mass) The composition for rubber gloves according to any one of claims 1 to 4.   The composition for rubber gloves as described in any one of Claims 1-5 which further contains a crosslinking agent.   The rubber glove which consists of a rubber composition obtained by bridge | crosslinking the composition for rubber gloves as described in any one of Claims 1-6.

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