WO2017126660A1 - Glove - Google Patents

Abstract

A glove in which the polymer main chain includes a structural unit derived from acrylonitrile, a structural unit derived from an unsaturated carboxylic acid, a structural unit derived from butadiene, and a structural unit derived from a self-crosslinking compound or from an organic crosslinking agent and in which a sulfur-free crosslinked structure has been formed.

Description

gloves

Embodiments of the present invention do not use a sulfur cross-linking agent or a sulfur-based vulcanization accelerator, but instead add a glove made of an elastomer cross-linked with a self-cross-linking compound or a non-polymerizable polyfunctional organic compound, and further with metal cross-linking. The present invention relates to gloves made of elastomer.

Rubber gloves are widely used in various industrial and medical fields such as the electronic component manufacturing industry and the pharmaceutical industry. Conventionally, as a rubber glove having excellent tensile strength and oil resistance, a latex composition obtained by crosslinking a carboxylated acrylonitrile-butadiene copolymer with a sulfur-based vulcanization accelerator such as sulfur and thiazole is dip-molded. The resulting gloves are used (International Publication No. 2001/053388). However, since sulfur and sulfur-based vulcanization accelerators cause various problems, particularly type IV allergy, various gloves using non-sulfur-based crosslinking have been proposed.

JP 2007-153948 A discloses a dip molding composition used for rubber gloves, and a predetermined amount of zinc oxide is added to acrylonitrile-butadiene rubber (NBR) latex obtained by using a specific pH adjuster. And a technique for increasing the mechanical strength of the dip-molded product is disclosed.

Japanese Patent Application Laid-Open No. 2007-177091 discloses an acid in which the dry film has a methyl ethyl ketone (hereinafter also referred to as “MEK”) insoluble content of 50 to 90% by weight and the MEK swelling degree of the insoluble content is 3 to 15. A composition for dip molding of modified nitrile rubber latex is described, and gloves obtained from this composition have disclosed sufficient mechanical properties such as tensile strength, elongation, tensile stress (300%) and excellent durability. Has been.

On the other hand, Japanese Patent Application Laid-Open No. 5-247266 discloses that the texture of the dip-molded product becomes hard when the MEK insoluble content is 50% by weight or more.
Japanese Patent Application Laid-Open No. 2010-144163 discloses a carboxylic acid-modified nitrile copolymer latex containing an unsaturated monomer having a crosslinkable functional group.

The applicant previously proposed a latex composition for gloves obtained by adding methacrylic acid and zinc oxide to carboxylated acrylonitrile butadiene (International Publication No. 2011/068394). The present applicant further found that the viscosity characteristics of this latex composition correlate with the tensile characteristics of the glove obtained as a dip-formed product, and proposed that the Mooney viscosity at 100 ° C. be defined as 100 to 220. (International Publication No. 2012/043894).

International Publication No. 2001/053388 JP 2007-153948 A JP 2007-177091 A JP-A-5-247266 JP 2010-144163 A International Publication 2011/068394 International Publication No. 2012/043894

As described above, a nitrile glove that has no mechanical problems (flexibility, tensile strength at break, elongation, etc.) and that does not use a sulfur crosslinking agent or sulfur vulcanization accelerator has been obtained. Already commercialized. However, in order to improve quality such as thinning, it is required to achieve even better characteristics.
Therefore, the present invention provides a glove obtained by using a latex (emulsion composition) that does not use a sulfur crosslinking agent and a sulfur-based vulcanization accelerator, which can produce a glove having excellent mechanical properties even if it is thin. The task is to do.

The solution of the present invention is a glove comprising an elastomer containing a structural unit derived from acrylonitrile, a structural unit derived from an unsaturated carboxylic acid, and a structural unit derived from butadiene in the polymer main chain, and a non-sulfur cross-linked structure is formed. The crosslinked structure is made of an elastomer having a crosslinked structure containing a structural unit derived from a self-crosslinkable compound in the polymer main chain or a crosslinked structure of a crosslinking agent that is a non-polymerizable polyfunctional organic compound. Regarding gloves.
The inventors have examined a self-crosslinking compound for self-crosslinking without sulfur in carboxylated nitrile butadiene rubber (hereinafter referred to as “XNBR”), and further, a similar effect can be obtained by using a general organic crosslinking agent. We found out that it was possible to complete the invention.

Another solution of the present invention further relates to a glove characterized by having a crosslinked structure with an aluminum complex or zinc.
It has been found that the tensile strength and chemical resistance can be increased by adding metal crosslinks to the cross-linked gloves.

Another solution of the present invention is that the self-crosslinkable compound is a polymerizable monomer containing a polymerizable unsaturated bond and any one functional group selected from an epoxy group, a silanol group, and an isocyanate group. About.
The inventors have identified a compound suitable for glove crosslinking in a further broad examination of the range of self-crosslinking compounds already found.

Another solving means of the present invention relates to a glove, wherein the non-polymerizable polyfunctional organic compound contains any one functional group selected from an epoxy group, a silanol group, an isocyanate group and an oxazoline group.
The inventors have examined and identified an organic crosslinking agent suitable for glove crosslinking.

Another solving means of the present invention relates to a glove wherein the non-polymerizable polyfunctional organic compound is any one compound selected from polyepoxide, polyisocyanate, polyoxazoline and silane coupling agent.
The inventors have identified the organic crosslinking agent in more detail.

Another solution of the present invention is that the structural unit derived from acrylonitrile is 20 to 35% by weight, the structural unit derived from unsaturated carboxylic acid is 3 to 8% by weight, and the structural unit derived from butadiene is 52 to 76.9% by weight. The present invention relates to a glove having a residual structural unit derived from a self-crosslinkable compound or a crosslinking agent of 0.1 to 5.0% by weight.
The inventors specified the weight ratio of each component in XNBR.

Another solution of the present invention relates to a glove having a tensile strength of 25 MPa to 50 MPa, an elongation at break of 400% to 750%, and a 100% modulus of 1.5 MPa to 10 MPa.
The above are physical properties of the obtained gloves.

Another solution of the present invention relates to a glove that does not include a crosslinked structure of sulfur as a crosslinking agent and a sulfur compound as a vulcanization accelerator.
This is the greatest problem itself of the present invention, which prevents type IV allergy due to sulfur crosslinking.

Another solution of the present invention relates to a glove having a crosslink density calculated from a measured value of dynamic viscoelasticity of 1.4 × 10 ⁻³ to 5.0 × 10 ⁻³ mol / cm ³ .
The above is the crosslink density of the glove obtained.

Another solution of the present invention relates to a glove having a toluene swelling ratio of 240-400%.
The above is the toluene swelling ratio of the obtained glove.

Another solution of the present invention relates to a glove having a thickness of 0.04 to 0.15 mm.
The above is the thickness of the glove obtained.

According to the embodiment of the present invention, since no sulfur crosslinking agent / sulfur vulcanization accelerator is used, there is no practical problem with type IV (delayed type) allergy (flexibility, tensile strength at break) XNBR gloves equipped with a stretch, etc.). In addition, a new self-crosslinking compound for self-crosslinking was identified, and a non-polymerizable polyfunctional organic compound as an organic crosslinking agent was also identified. Furthermore, in addition to the conventionally known zinc which is a metal bridge | crosslinking to this, the glove which increased tensile strength and chemical resistance was able to be made using the aluminum complex.

FIG. 1 shows the ¹ H-NMR spectrum measurement result of the methanol-soluble part of the elastomer contained in the emulsion composition of one embodiment of the present invention. FIG. 2 shows the result of FT-IR transmittance spectrum measurement of the CD ₃ OD soluble part of the elastomer contained in the emulsion composition of one embodiment of the present invention. FIG. 3 shows the results of FT-IR absorbance spectrum measurement of a dry elastomer film contained in the emulsion composition of one embodiment of the present invention. FIG. 4 is a schematic diagram showing self-crosslinking in an elastomer molecule and crosslinking by a crosslinking agent. FIG. 5 shows the measurement results of the dynamic viscoelasticity of an elastomer dry film contained in the emulsion composition of one embodiment of the present invention. FIG. 6 shows the measurement results of the dynamic viscoelasticity of a glove obtained using the emulsion composition of one embodiment of the present invention.

1. Glove Embodiments In the present invention, there are three embodiments described below.

A. XNBR is polymerized with a self-crosslinkable compound to form a covalent bond, and further dip-molded into a glove (first embodiment, in the case of the structural unit derived from the self-crosslinkable compound of claim 1)
The elastomer includes at least a structural unit derived from acrylonitrile, a structural unit derived from an unsaturated carboxylic acid, a structural unit derived from butadiene, and a structural unit derived from a self-crosslinkable compound.

The ratio of each structural unit is not particularly limited. In the elastomer, 20 to 35% by weight of an acrylonitrile-derived structural unit (acrylonitrile residue) and an unsaturated carboxylic acid-derived structural unit (unsaturated carboxylic acid residue) are contained. 3 to 8% by weight, butadiene-derived structural unit (butadiene residue) is 52 to 76.9% by weight, and derived from a self-crosslinkable compound as the remaining structural unit derived from a non-sulfur-based crosslinked structure The structural unit is preferably 0.1 to 5.0% by weight. When the self-crosslinking compound is less than 0.1% by weight, there is a possibility that sufficient tensile strength and elongation at break cannot be obtained. If it exceeds 5.0% by weight, the detailed cause is unknown, but good film formation may not be possible.
The ratio of these structural units can be simply determined from the weight ratio of the raw materials used for producing the elastomer.

More specifically, XNBR preferably contains 20 to 35% by weight of acrylonitrile residue, more preferably 23 to 30% by weight, from the viewpoint of ensuring strength and flexibility.
The amount of the unsaturated carboxylic acid residue is preferably 3 to 8% by weight and preferably 4 to 7% by weight in order to maintain the physical properties of the rubber glove as a final product having an appropriate cross-linked structure. Is more preferable.
The amount of acrylonitrile residues can be determined by converting the amount of nitrile groups from the amount of nitrogen atoms determined by elemental analysis. The amount of the unsaturated carboxylic acid residue can be determined by quantifying the carboxyl group and the carbonyl group derived from the carboxyl group by infrared spectroscopy (IR) or the like.

The amount of butadiene residues is preferably 52 to 76.9% by weight, more preferably 62 to 74% by weight, and still more preferably 66 to 72% by weight. When the amount of butadiene residues is within the above range, a final product having excellent physical properties can be obtained.
The amount of the self-crosslinking compound is more preferably 0.5 to 4% by weight, and more preferably 1.5 to 4% by weight, which is about half of the content of the unsaturated carboxylic acid.

The structural unit derived from butadiene is preferably a structural unit derived from 1,3-butadiene.
The unsaturated carboxylic acid that forms the structural unit derived from the unsaturated carboxylic acid is not particularly limited, and may be a monocarboxylic acid or a polycarboxylic acid.
More specifically, acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid and the like can be mentioned. Especially, acrylic acid and / or methacrylic acid (henceforth "(meth) acrylic acid") are used preferably, More preferably, methacrylic acid is used.

The self-crosslinking compound is a polymerizable compound contained in the polymer chain of the elastomer, and is a monomer having a functional group capable of forming intramolecular crosslinking or intermolecular crosslinking (hereinafter also simply referred to as “crosslinking”). means.
That is, the self-crosslinkable compound is a compound (polymerizable monomer) having a polymerizable unsaturated bond (polymerizable unsaturated bond) and one or more functional groups capable of forming a crosslink. Although not particularly limited, preferably, the polymerizable unsaturated bond is a vinylene group (carbon-carbon double bond), and examples of the reactive functional group include a methylol group, an acetyl group, a hydroxyl group, an epoxy group, a silanol group, One or more functional groups selected from the group consisting of an alkoxysilyl group, an isocyanate group, and an amino group are preferred.
In the present invention, the inventors focused on the epoxy group, silanol group and isocyanate group among the above.

This polymerizable monomer may be a monofunctional monomer containing one of these specific functional groups, or may be a polyfunctional monomer containing two or more functional groups. In the case of a polyfunctional monomer, the plurality of functional groups may be the same or different from each other.
Examples of the crosslinks formed include ester bonds, amide bonds, amide ester bonds, imide bonds, vinyl bonds, etc., between the carboxyl group of an unsaturated carboxylic acid and the functional group of the polymerizable monomer, or of the polymerizable monomer. Examples thereof include bonds generated by elimination reaction or substitution reaction between functional groups.

Examples of self-crosslinkable compounds include 2-hydroxyalkyl (meth) acrylate (eg, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, etc.), N-methylol Acrylamide, N- (isobutoxymethyl) acrylamide, hydroxymethylated diacetone acrylamide, N-formyl-N'-acryloylmethylenediamide, 4-hydroxybutyl acrylate glycidyl ether, 2-isocyanatoethyl methacrylate, vinyltrimethoxysilane, vinyltri Ethoxysilane, vinyltris (2-methoxyethoxy) silane, acrylamide, glycerin triacrylate, trimethylolpropane triacrylate, N- (1,1-di Chill 3-oxobutyl) like acrylamide (diacetone acrylamide) and the like.

The elastomer may further contain a structural unit derived from another polymerizable compound. Examples of other polymerizable compounds include aromatic vinyl monomers such as styrene, α-methylstyrene, and dimethylstyrene; Ethylenically unsaturated carboxylic acid amides such as acrylamide and N, N-dimethylacrylamide; ethylene such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate Unsaturated unsaturated carboxylic acid alkyl ester monomer; and vinyl acetate. Any one of these or a combination of a plurality of these can be used arbitrarily.

The elastomer of the present embodiment includes a non-sulfur-based crosslinked structure formed by a crosslinked structure of the self-crosslinkable compound formed between carboxyl groups derived from unsaturated carboxylic acid. Due to the presence of the self-crosslinking compound, crosslinking is formed in the polymer chain of the elastomer, for example, by dehydration by heating, without adding a separate crosslinking agent. That is, while the self-crosslinking compound constitutes the polymer main chain, one or more functional groups thereof react with a carboxyl group derived from an unsaturated carboxylic acid (see FIG. 4B), or the functional group It is considered that a cross-linked structure is formed by reacting between groups (see FIG. 4A).

4 (a) and 4 (b) schematically show crosslinking when the self-crosslinking compound is N-methylolacrylamide. FIG. 4 (a) shows that functional groups derived from N-methylolacrylamide in the XNBR molecule form a crosslinked structure. FIG. 4 (b) shows that the carboxyl group of the unsaturated carboxylic acid in the XNBR molecule forms a crosslinked structure with the functional group derived from N-methylolacrylamide.

As described above, the elastomer of the present embodiment includes a cross-linked structure of a self-crosslinkable compound as a characteristic configuration.
A self-crosslinking compound such as N-methylolacrylamide can be added to an acrylonitrile-butadiene-unsaturated carboxylic acid elastomer having a relatively low degree of polymerization to allow the elastomer to self-crosslink, and have a Mooney viscosity in an appropriate range. It was found that a glove having excellent mechanical properties such as tensile strength at break and 100% modulus was obtained.

Here, since the Mooney viscosity corresponds to the molecular weight of the polymer, that the Mooney viscosity is the same and the crosslinking density is large means that the molecular weight between the crosslinking points is small. Also, the high crosslink density means that the polymer has many branches and the molecular chain network is dense.
The crosslink density n can be obtained from the storage elastic modulus E ′ in the rubber-like region near room temperature, and the crosslink density n increases as the storage elastic modulus E ′ increases. Further, regarding the storage elastic modulus E ′, the slope of the storage elastic modulus E ′ on the high temperature region side is known as an index of the molecular weight, and the molecular weight (molecular) is determined by the slope (temperature dependence) of the storage elastic modulus E ′. It is known that the chain length is different.

In general, the latex for forming a glove is subjected to first-stage crosslinking and second-stage crosslinking. Specifically, the glove is manufactured using the elastomer subjected to the first stage cross-linking as a dipping solution. At that time, the second stage cross-linking is further performed on the surface of the mold or former for forming the glove. Thus, a glove having sufficient mechanical strength as a glove is formed.
The glove in the present embodiment is characterized in that the second-stage crosslinking is performed with calcium as a coagulant.

The elastomer of this embodiment is the one after the first stage crosslinking. That is, the elastomer of the present embodiment includes crosslinking by a self-crosslinking compound as the first step crosslinking, but in addition to this, crosslinking by autoxidation of carboxyl groups, crosslinking by Michael reaction of acetoacetoxy groups and unsaturated bonds. Etc. may be included.

As the elastomer, an unsaturated carboxylic acid such as acrylonitrile, (meth) acrylic acid, butadiene such as 1,3-butadiene, and a self-crosslinking compound are used. According to a conventional method, an emulsifier, a polymerization initiator, a molecular weight modifier, etc. It can be prepared by the emulsion polymerization used. Water at the time of emulsion polymerization is preferably contained in an amount such that the solid content is 30 to 60% by weight, and more preferably contained in an amount such that the solid content is 35 to 55% by weight.

Examples of the emulsifier include anionic surfactants such as dodecylbenzene sulfonate and aliphatic sulfonate; cationic surfactants such as polyethylene glycol alkyl ether and polyethylene glycol alkyl ester; and amphoteric surfactants. An anionic surfactant is preferably used.

The polymerization initiator is not particularly limited as long as it is a radical initiator, but inorganic peroxides such as ammonium persulfate and potassium perphosphate; t-butyl peroxide, cumene hydroperoxide, p-menthane hydroperoxide, diester Organic peroxides such as t-butyl peroxide, t-butyl cumyl peroxide, dibenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, t-butyl peroxyisobutyrate; azobisisobuty Examples include azo compounds such as rhonitrile, azobis-2,4-dimethylvaleronitrile, azobiscyclohexanecarbonitrile, methyl azobisisobutyrate.

Examples of the molecular weight modifier include mercaptans such as t-dodecyl mercaptan and n-dodecyl mercaptan, and halogenated hydrocarbons such as carbon tetrachloride, methylene chloride and methylene bromide. T-dodecyl mercaptan; n-dodecyl mercaptan, etc. The mercaptans are preferred.

The Mooney viscosity (ML (1 + 4) (100 ° C.)) of the obtained elastomer is preferably 100 or more, preferably 220 or less, more preferably 100 to 200, in order to obtain sufficient strength. . The upper limit value (220) of the Mooney viscosity is an actual measurement limit of the Mooney viscosity. If the Mooney viscosity exceeds the upper limit (220), the viscosity is high and molding processing becomes difficult.

Moreover, in this elastomer, it is preferable that the content of elemental sulfur detected by a combustion gas neutralization titration method is 1% by weight or less of the weight of the elastomer.
Quantification is performed by absorbing a combustion gas generated by burning 0.01 g of a XNBR sample in air at 1350 ° C. for 10 to 12 minutes in H ₂ O ₂ water to which a mixed indicator is added, and adding a 0.01 N NaOH aqueous solution. It can carry out by the method of Japanese titration.

I. Gloves formed by covalent bonding with an organic cross-linking agent by dip molding to ordinary XNBR (second embodiment, in the case of the structural unit derived from the polyfunctional organic compound of claim 1)
In the above A, a covalent bond was formed by a self-crosslinking compound instead of sulfur crosslinking at the time of XNBR polymerization. Type) Since the same effect of preventing allergy is obtained, various studies have been made on organic crosslinking agents.

The organic crosslinking agent will be described. An organic crosslinking agent is a compound that does not contain a polymerizable functional group, contains two or more functional groups in the molecule, and thereby crosslinks the polymer chain. The crosslinking agent is not particularly limited as long as it is a non-polymerizable polyfunctional organic compound (that is, having no polymerizable unsaturated bond). For example, hydroxyl group, epoxy group, silanol group, alkoxysilyl group, isocyanate group , An oxazoline group, a hydrazide group, an amino group, and an aziridine group, and preferably include two or more functional groups that are the same or different. This polyfunctional organic compound may contain a functional group other than these, for example, an ether group.
The inventors paid particular attention to epoxy groups, silanol groups, isocyanate groups and oxazoline groups.

Here, the amino group includes both the amino group (—NH ₂ ) of the primary amine and the substituted amino group (—NHR, R is a hydrocarbon group) of the secondary amine.
The cross-linking bond between carboxyl groups by these cross-linking agents is typically, for example, an ester bond, an amide bond, or an imide bond.

Specifically, polyhydric alcohol, polyhydric phenol, polyhydric amine, amino alcohol, aminophenol, polyepoxide, silane coupling agent, polyisocyanate such as diisocyanate, polyoxazoline, polyhydrazide and polyaziridine are used as the crosslinking agent. It is possible to arbitrarily combine a plurality of organic compounds.
The inventors paid particular attention to polyepoxides, silane coupling agents, polyisocyanates such as diisocyanates and polyoxazolines.
In addition, as the crosslinking agent, various polymers containing the above functional group containing a main chain or a side chain can be used, and some of them are exemplified below.

The polyhydric alcohol is an aliphatic hydrocarbon compound having two or more hydroxyl groups in the molecule. Either a chain type or an alicyclic type may be used, and an unsaturated bond, an ether bond or the like may be included. Further, the number of hydroxyl groups is not particularly limited, but dihydric alcohol (diol) and trihydric alcohol (triol) can be preferably used.
More specifically, the divalent or trivalent alcohol having 2 to 6 carbon atoms is ethylene glycol, diethylene glycol, triethylene glycol, propanediol, butanediol, pentanediol, hexanediol, glycerin, butenediol (2-butenediol). 1,4-diol, etc.), pentenediol (2-pentene-1,5-diol, etc.), cyclopentanediol, cyclohexanediol and the like. The position of the hydroxyl group in the carbon chain is not particularly limited.

Polyhydric alcohol and polyhydric phenol are concepts including a methylol compound. Examples of the methylol compound include trimethylolpropane, various methylol-formyl compounds (2,6-dihydroxymethyl-4-methylphenol and the like) commercially available from Asahi Organic Materials Co., Ltd., and Nippon Car. Examples include melamine / formaldehyde initial condensate (methylol melamine) commercially available from Bite Industries Co., Ltd.

As the diol, ethylene glycol, diethylene glycol, and triethylene glycol (repetition number n = 1 to 3) can be preferably used, but polyethylene glycol (or oligomer) having an average molecular weight of about 400 to 6,000 is preferably used. You can also. As the polyethylene glycol oligomer, those having a repeating number n of about 2 to 15 can be preferably used, and for example, those having a molecular weight of 400 to 700 can be preferably used. In addition, ethylene glycol or polyethylene glycol having a repeating number n of 1 to 15 can be used in combination, and an elastomer having almost the same tetrahydrofuran-insoluble component content can be obtained even if the number of n varies within this range. A glove having substantially the same physical properties can be obtained using the elastomer.

The polyhydric phenol is an aromatic hydrocarbon compound having two or more hydroxyl groups bonded to an aromatic ring in the molecule. The structure is not particularly limited, and may be phenols having one benzene nucleus, divalent bisphenols having two benzene nuclei, and binaphthols having a naphthalene nucleus.
Specific examples include dihydroxybenzene (hydroquinone, resorcinol, catechol), trihydroxybenzene (benzenetriol), dihydroxynaphthalene, naphthalenetriol, and the like.

The polyvalent amine is a compound having two or more primary or secondary amino groups in the molecule, and may be either aliphatic or aromatic. The amino group is preferably a primary amine from the viewpoint of reactivity, but a secondary amine can also be used.
Specifically, examples of the alkylene diamine having 2 to 6 carbon atoms include ethylene diamine, cadaverine, and hexamethylene diamine, and examples of the aromatic diamine include paraphenylene diamine. Examples of the triamine include propane-1,2,3-triamine, pentanetriamine and the like. The substitution position of the amino group in the molecule is not particularly limited. A polymer containing a plurality of amino groups (primary or secondary) such as aminoethylated acrylic polymer and polyallylamine can also be used.

An amino alcohol is a compound having an amino group and a hydroxyl group in the molecule.
Specific examples include methanolamine, ethanolamine, propanolamine, diethanolamine, triethanolamine, and N-methylethanolamine, but are not limited thereto.

Aminophenol is an aromatic compound having an amino group and a phenolic hydroxyl group in the molecule. Specific examples include 4-aminophenol, 3-amino-2-naphthol, 1-amino-2-naphthol, and the like, but are not limited thereto.

A polyepoxide is a compound containing two or more epoxy groups in a molecule. The epoxy group is opened by hydrolysis during cross-linking, and the resulting hydroxyl group reacts with the carboxyl group.
Specific examples include 1,5-hexadiene diepoxide, 1,7-octadiene diepoxide, diethylene glycol diglycidyl ether, and the like, but are not limited thereto.

A polyisocyanate is a compound containing two or more isocyanate groups. Preferably, a diisocyanate can be used, and the diisocyanate may be either an aliphatic (acyclic or alicyclic) diisocyanate or an aromatic diisocyanate, and specifically, p-phenylene diisocyanate, p-tolyl diisocyanate, hexa Examples include methylene diisocyanate.
Polyisocyanate compounds containing blocked isocyanate groups such as “Elastolon BN” series manufactured by Daiichi Kogyo Seiyaku Co., Ltd. can also be used.

A polyoxazoline is a compound containing two or more oxazoline groups in the molecule (that is, an atomic group obtained by removing one hydrogen atom from oxazoline). The oxazoline group is opened at the time of crosslinking formation and reacts with a carboxyl group to form a crosslinked structure (amide ester bond).
The polyoxazoline is preferably a polymer containing an oxazoline group. The oxazoline group-containing polymer is not particularly limited as long as it is a compound containing two or more oxazoline groups. For example, a commercially available product having a molecular weight of about 10,000 or less (“Epocross” manufactured by Nippon Shokubai Co., Ltd.) can be used.

Polyhydrazide is a compound containing _two or more hydrazide groups (or acid hydrazide groups; —CONHNH ₂ ) in the molecule. Hydrazide is a compound corresponding to a dehydration condensation product between the amino group of hydrazines and the carboxyl group of carboxylic acid.
As the polyhydrazide, a dihydrazide containing two hydrazide groups can be preferably used, and examples thereof include adipic acid hydrazide, sebacic acid hydrazide, and isophthalic acid dihydrazide. As a dihydrazide, the commercial item marketed from Otsuka Chemical Co., Ltd. can be used, for example.
Here, since the hydrazide group reacts with the carbonyl group, when polyhydrazide is used as the crosslinking agent, a carbonyl group-containing polymerizable compound such as diacetone acrylamide or 2-acetoxyethyl methacrylate is used as the self-crosslinking compound. It is preferable to form a crosslinked structure by reacting the carbonyl group of the self-crosslinkable compound incorporated in the polymer chain with a hydrazide group. The hydrazide group is considered to react with the carbonyl group of the polymer chain to form a crosslinked structure with a bond of “—CO—NH—N═C <”.

Polyaziridine is a compound containing two or more aziridine groups (aziridine rings). For example, “Chemite” (2,2-bishydroxymethylbutanol-tris [3- (1-aziridinyl) propionate], 4,4-bis (ethyleneiminocarboxyl) commercially available from Nippon Shokubai Co., Ltd. as a polyfunctional aziridine Amino) diphenylmethane) can be preferably used.

A silane coupling agent is a silane compound having both a hydrolyzable group and an organic functional group. The hydrolyzable group is typically a lower alkoxy group such as a methoxy group or an ethoxy group, or an acyl group such as an acetyl group. The organic functional group is preferably an amino group, an epoxy group, or the like, and the silane coupling agent having these functional groups is also called aminosilane or epoxysilane.
More specifically, for example, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropylmethyldimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-aminopropyltrimethoxysilane, A methoxysilane etc. are mentioned, A commercially available silane coupling agent can be used.

Since the crosslinked structure by the organic crosslinking agent can include various crosslinked structures, the degree of freedom in production increases, and various physical properties of the elastomer can be easily changed depending on the type of crosslinking.

While XNBR self-crosslinks at the time of polymerization, an organic crosslinking agent reacts with two or more carboxyl groups derived from unsaturated carboxylic acid (see FIG. 4 (c)) to form a crosslinked structure. It is thought to form.
FIG. 4 (c) shows that when the crosslinking agent is polyethylene glycol (however, the description of the leftmost OH group and the rightmost H is omitted), the carboxyl group of the unsaturated carboxylic acid in the XNBR molecule is It schematically shows that a crosslinked structure is formed by an ester bond.

C. A glove obtained by adding a cross-linked structure obtained by further ion-bonding with an aluminum complex or zinc to the cross-links of (a) and (b) (third embodiment, claim 2)
The above gloves (a) and (b) are covalently bonded by a self-crosslinkable compound at the time of polymerization of XNBR and a polyfunctional organic compound at the time of non-polymerization, but both are ultimately combined with an ionic bond of calcium as a coagulant. Has a cross-linked structure.
Calcium is easily eluted in artificial sweat, so the tensile strength is likely to decrease, and the ionic radius is large compared to other metal cross-linking agents such as zinc or aluminum complexes, and the organic solvent impermeability is insufficient. It was considered effective to partially replace the calcium bridge with an aluminum complex or zinc bridge. Further, the tensile strength and chemical resistance can be controlled by increasing the amount of zinc or aluminum complex.

The polyvalent metal compound used as a metal crosslinking agent ion-crosslinks functional groups such as unreacted carboxyl groups in XNBR. As the polyvalent metal compound, zinc which is a divalent metal oxide is most commonly used. Moreover, aluminum which is a trivalent metal can be used as a crosslinking agent by making this a complex. Aluminum has the smallest ionic radius and is optimal for chemical resistance and tensile strength, but if it is added too much, it becomes too hard to handle.
The content of the divalent metal oxide is 0.5 to 4.0 parts by weight, preferably 0.7 to 3.0 parts by weight with respect to 100 parts by weight of XNBR.

As the aluminum complex, aluminum polybasic hydroxycarboxylate is used. A 10% aqueous solution of polybasic hydroxycarboxylic acid (hydroxycarboxylic acid (citric acid, malic acid, tartaric acid) was prepared.
[(AlCit) ₃ (OH) ₄ ] ^7- obtained from water-soluble aluminum citrate complex [(AlCit) ₃ (OH) (H ₂ O ₄ )] ^4- has four hydroxyl groups and is a cross-linked carboxyl group ("Synthesis and application to rubber latex", Chiba Prefectural Industrial Technology Research Institute Report No. 8, pages 22-27 (October 2010).

D. Other components A dip solution for dip-molding a glove contains at least the above-mentioned elastomer or ordinary XNBR and water. Hereinafter, the dip solution is also referred to as “emulsion composition”. As will be described later, when this emulsion composition is used as a dipping liquid or the like during the production of gloves, the amount of water is preferably such that the solid content concentration is 18 to 30% by weight.

The emulsion composition further includes a dispersant. As the dispersant, an anionic surfactant is preferable. For example, carboxylate, sulfonate, phosphate, polyphosphate ester, polymerized alkylarylsulfonate, polymerized sulfonated naphthalene, polymerized naphthalene / formaldehyde A condensation polymer etc. are mentioned, Preferably a sulfonate is used.
A commercial item can be used for a dispersing agent. For example, TamolNN9104 can be used. The amount used is preferably about 0.5 to 2.0 parts by weight with respect to 100 parts by weight of the elastomer (or solid content of the emulsion composition) in the emulsion composition.

The emulsion composition contains a pH adjuster. As the pH adjuster, potassium hydroxide is preferably used, and the amount used is usually 0.1 to 2.0 weights per 100 parts by weight of the elastomer (or the solid content of the emulsion composition) in the emulsion composition. Part of the pH adjuster can be used.

The emulsion composition can further contain various other additives. Examples of the additive include an antioxidant, a pigment, and a chelating agent. As the antioxidant, a hindered phenol type antioxidant, such as Wingstay L, can be used. As the pigment, for example, titanium dioxide is used. As the chelating agent, sodium ethylenediaminetetraacetate or the like can be used.

In a preferred embodiment, the composition comprises 100 parts by weight of the elastomer, 0.5 to 4.0 parts by weight of a divalent metal ion and a cross-linking agent, and a pH adjusting agent for adjusting the pH to 9 to 10 0.1-2. It consists of 0 part by weight, 0.5 to 2.0 parts by weight of a dispersant, and water. An emulsion composition of the XNBR can be prepared by adding water so that the concentration of the total solid phase material (TSC) is 18 to 30% by weight.

The emulsion composition of the present embodiment can be prepared by mixing the XNBR component, additives as necessary, such as a dispersant and an antioxidant, and water using a conventional mixing means such as a mixer.

2. Physical Properties of Glove The glove of the present embodiment is obtained using the above emulsion composition.
Its properties include tensile strength of 25 MPa to 50 MPa, elongation at break of 400% to 750%, more preferably elongation at break of 400% to 700% or 400% to 650%, 100% modulus (elongation of 100 %, More preferably 100% modulus of 2 MPa to 10 MPa. Here, 100% modulus is a characteristic used as an index value of the hardness (rigidity) of a glove.
More preferably, the tensile stress is 35 to 50 MPa, the elongation at break is 400 to 480%, and the 100% modulus is 4 to 10 MPa. The glove swelling ratio at the time of glove formation is preferably 200 to 400%. Here, the glove swelling ratio at the time of glove formation means the toluene swelling ratio as a characteristic of the dry film of the elastomer in the emulsion composition, and is a numerical value that is a measure of the cross-linking density of the glove.

The crosslink density (value calculated from the measured dynamic viscoelasticity) indicating the density of the non-sulfur-containing crosslinked structure of the rubber of the glove is 1.4 × 10 ⁻³ to 5.0 × 10 ⁻³ mol / cm ³ . It is preferably 1.5 to 4.5 × 10 ⁻³ mol / cm ³ .
The crosslink density of the rubber of the glove can be calculated from the toluene swelling rate described later, and the crosslink density of the glove calculated from the toluene swelling rate is preferably 0.10 to 1.5 mol / cm ^3. More preferably, it is 15 to 1.0 mol / cm ³ .
The toluene swelling ratio of the glove is preferably 240% or more from the viewpoint of ensuring flexibility, and preferably 400% or less from the viewpoint of ensuring strength.
The thickness of the glove is not particularly limited, but is preferably 0.04 to 0.15 mm.

In addition, the characteristic of these gloves is a characteristic obtained by further performing the second-stage crosslinking during the production of the gloves on the above-mentioned elastomer or ordinary XNBR subjected to the first-stage crosslinking. In the glove of this embodiment, it is preferable not to use sulfur as a second-stage cross-linking agent and not to use a sulfur compound that is a vulcanization accelerator.
That is, the glove is preferably a glove that does not contain both sulfur as a crosslinking agent and sulfur compound as a vulcanization accelerator, and the content of elemental sulfur detected by the neutralization titration method of combustion gas is It is preferably 1% by weight or less of the glove weight.

3. Manufacturing method of glove The glove of this embodiment can be preferably manufactured with the following manufacturing methods.
That is,
(1) a step of immersing the glove forming mold in a coagulant solution and attaching the coagulant to the glove forming mold;
(2) a step of immersing the glove forming die attached with the coagulant in the emulsion composition of the present embodiment; and (3) a step of heating the glove forming die attached with the emulsion composition.
Is a manufacturing method by dipping method.

In more detail, a glove can be manufactured as follows.
(A) A step of immersing a mold or a former (glove mold) in a coagulant solution containing 5 to 20% by weight, preferably 8 to 17% by weight of Ca ²⁺ ions as a coagulant and a gelling agent. Here, the time for attaching the coagulant or the like to the surface of the mold or former is appropriately determined, and is usually about 10 to 20 seconds. As the coagulant solution, for example, an aqueous solution containing 5 to 20% by weight of a coagulant such as calcium nitrate or calcium chloride or an aggregating agent such as an inorganic salt having an effect of precipitating an elastomer is used.

(B) A step of drying the entire surface or part of the surface by drying the mold or former to which the coagulant is adhered at 50 to 70 ° C.
(C) A step of immersing the mold or former after drying in the step (b) in the emulsion composition at a temperature of 25 to 35 ° C. for 1 to 60 seconds. Here, the emulsion composition is attached to the mold or former to which the coagulant is attached.

(D) The mold or former to which the emulsion composition is adhered in the step (c) is dried at 80 to 120 ° C., usually for 20 to 70 seconds, and then the mold or former to which the elastomer is adhered is washed with water. Removing. Here, the partially dried elastomer-coated mold or former is leached in hot or warm water (30-70 ° C.) for 90-140 seconds.

(E) A step of drying the mold or former washed in the step (d) in the furnace at 80 to 120 ° C. A beading (sleeve winding) process may be performed after the leaching process is completed, and the mold or former is dried in an oven at 80 to 120 ° C. for 250 to 300 seconds.

(F) A step in which the mold or former dried in the step (e) is heated at 120 ° C. to 150 ° C. for 20 to 30 minutes to post-heat (crosslink and cure) the elastomer.
In this step (f), the second stage of crosslinking of the elastomer is performed, whereby a rigid molecular chain is formed, and the above-mentioned various desirable properties can be imparted to the glove.

This second-stage crosslinking is performed by calcium crosslinking alone, organic crosslinking agent and calcium crosslinking, or organic crosslinking agent and calcium and polyvalent metal crosslinking. Thus, the resulting glove is formed by covalent bonding by organic crosslinking and ionic crosslinking by metal crosslinking.

The content of the polyfunctional organic compound as the crosslinking agent in the second stage is preferably 1 part by weight or more with respect to 100 parts by weight of XNBR, and when an excessive amount is added, the number of crosslinking points increases and the crosslinking density is high. Since it becomes too much and film formation may be difficult at the time of film formation, it is preferably 10 parts by weight or less, and more preferably 5 parts by weight or less.

<Production of emulsion composition a)
In a pressure-resistant polymerization reactor equipped with a stirrer, ion-exchanged water, acrylonitrile, 1,3-butadiene, methacrylic acid, N-methylolacrylamide, 2-hydroxyethyl methacrylate, sodium dodecylbenzenesulfonate, diethylene glycol, in amounts shown in Table 1, respectively, An emulsion composed of potassium persulfate and sodium ethylenediaminetetraacetate was added, and the mixture was allowed to react for 12 to 24 hours while maintaining at 50 ° C. After removing unreacted monomers from the obtained copolymer latex, the pH and concentration of the copolymer latex were adjusted to obtain an elastomer latex (emulsion composition) of Example 1.

In the same manner as in Example 1, the raw materials shown in Tables 1 and 2 were used and polymerized under the polymerization conditions shown in the same table to produce emulsion compositions of Examples 2 to 15.
In Table 2, etc., the “diepoxy compound” used as the polyfunctional organic compound is diethylene glycol diglycidyl ether (Epolite 100E, manufactured by Kyoeisha Chemical Co., Ltd.) containing an epoxy group at both ends.

Further, as shown in Table 6, the emulsion compositions of Comparative Examples 1 to 3 and Comparative Example 5 were produced in the same manner as the emulsion composition of Example 1 without adding HEMA and diethylene glycol.
Furthermore, Nippon Polon 550 manufactured by Nippon Zeon Co., Ltd., which is a commercially available NBR elastomer, was used as Comparative Example 4.

The properties of each elastomer latex were measured as follows.
<Acrylonitrile (AN) residue amount and unsaturated carboxylic acid residue>
Each elastomer latex was dried to form a film. The film was measured by FT-IR, and the absorbance (Abs) was determined at an absorption wavelength of 1699 cm ⁻¹ derived from a carboxylic acid group and an absorption wavelength of 2237 cm ⁻¹ derived from an acrylonitrile group, and the amount of acrylonitrile residue and the amount of unsaturated carboxylic acid residue were determined. The basis weight was determined. The amount of acrylonitrile residue was determined from a calibration curve prepared from a sample in which polyacrylic acid was added as an internal standard substance to each elastomer in advance and the acrylonitrile group amount was known. The amount of unsaturated carboxylic acid residue was determined from the following formula.
Unsaturated carboxylic acid residue amount (wt%) = [Abs (1699 cm ⁻¹ ) / Abs (2237 cm ⁻¹⁾ ] /0.2661
In the above formula, the coefficient 0.2661 is a conversion value obtained by creating a calibration curve from a plurality of samples in which the ratio between the amount of unsaturated carboxylic acid groups and the amount of acrylonitrile groups is known.

<Mooney viscosity (ML _{(1 + 4)} )>
Each elastomer latex was dropped with a pipette while 200 ml of a saturated aqueous solution of a 4: 1 mixture of calcium nitrate and calcium carbonate was stirred at room temperature to precipitate a solid rubber. Take out the resulting solid rubber, repeat stirring and washing with about 1000 ml of ion-exchanged water 10 times, then squeeze and dehydrate the solid rubber and vacuum dry (60 ° C, 72 hours) to prepare a rubber sample for measurement did. The obtained rubber for measurement was passed through a 6-inch roll with a roll temperature of 50 ° C. and a roll gap of about 0.5 mm several times until the rubber was collected. JIS K6300-1: 2001 “Unvulcanized rubber—physical properties The viscosity was measured at 100 ° C. using a large-diameter rotating body in accordance with “Part 1: Determination of viscosity and scorch time using Mooney viscometer”. In addition, the viscosity of the latex of Comparative Example 5 exceeded the measurement upper limit (220) at a measurement temperature of 100 ° C.

<Sulfur content>
0.1 g of solid in the elastomer latex is burned in a combustion furnace at 1350 ° C for 12 minutes, and the generated combustion gas is absorbed into the absorption liquid (H ₂ O ₂ water mixture with one to several drops of dilute sulfuric acid). After that, neutralization titration with 0.01N NaOH water was performed for quantification.

<1H-NMR spectrum>
FIG. 1 shows a ¹ H-NMR spectrum measured using the elastomer latex of Example 1.
Specifically, ¹ H-NMR spectrum of the MeOH soluble part was measured using an elastomer latex using a measuring apparatus: EX400 type manufactured by JEOL Ltd. Measurement conditions are observation nucleus: ¹ H, solvent: CD ₃ OD.

<FT-IR spectrum>
FIG. 2 shows an FT-IR transmission spectrum measured using the elastomer latex of Example 1.
Specifically, the FT-IR transmittance spectrum of the CD ₃ OD soluble part of the elastomer latex was measured with a measuring device: FT / IR Continuous type manufactured by Thermo Fisher Scientific. The measurement conditions are a microscopic transmission method and a resolution of 4 cm ⁻¹ .
FIG. 3 shows the measurement results of the FT-IR absorbance spectrum of the dry film of the elastomer latex of Example 1. The measurement apparatus used was FT / IR-4200 manufactured by JASCO Corporation, and the measurement conditions were a single reflection ATR method and a resolution of 4 cm ⁻¹ .

As shown in the measurement example of ¹ H-NMR spectrum of the elastomer latex in FIG. 1, a decomposition spectrum of ethylene glycol oligomer was observed in the vicinity of 3.5 and 3.6 ppm.
As shown in the measurement example of the FT-IR absorbance spectrum of the elastomer latex in FIG. 3, peaks indicating unreacted carboxyl groups and carboxylate esters were observed near 1700 cm ⁻¹ and 1730 cm ⁻¹ , respectively. In the measurement example of the FT-IR transmittance spectrum of the elastomer latex in FIG. 2, no peak was observed in the vicinity of 1730 cm ⁻¹ .

From the results shown in FIGS. 1 to 3, in the acrylonitrile butadiene elastomer molecule in which the unsaturated carboxylic acid is introduced, the carboxyl group of the unsaturated carboxylic acid in the acrylonitrile butadiene elastomer molecule is different from that in the acrylonitrile butadiene elastomer molecule that is the same or different. As schematically shown in FIG. 4, in addition to self-crosslinking with n-methylolacrylamide, the carboxyl group of the saturated carboxylic acid is cross-linked with each other by dehydration condensation with an ethylene glycol oligomer and esterification. I guess that.

<Manufacture of gloves>
With respect to 100 parts by weight of each elastomer latex (in terms of solid content), as shown in “(3) Glove production conditions” in Tables 1 and 2, respectively, zinc oxide was added as a second-stage cross-linking agent with a mixer. The mixture was stirred to prepare the dipping liquids (emulsion compositions) of Examples 1 to 11 and Example 15. Examples 12 to 14 are examples in which the second-stage crosslinking agent was not added. Here, the amount of zinc in the table is the amount obtained by ICP-AES analysis of the dissolved glove.
Although not shown in the table, at the time of glove production, in addition to the second-stage crosslinking agent described in the table, 1.35 parts by weight of a pH adjuster (potassium hydroxide), pigment (titanium oxide) 0. 5 parts by weight, dispersant (sodium alkylbenzenesulfonate) 0.5 parts by weight, antioxidant (2,4,6-tri-tertbutylphenol) 0.25 parts by weight, and colorant (titanium oxide) 0.05 parts by weight Part was further added to the dipping solution.

As shown in Tables 3 and 4, as Examples 16 to 30, the emulsion composition of Example 1 was used, and the second-stage crosslinking agent was changed from zinc oxide to a polyfunctional organic compound. A liquid was prepared. However, Example 17 in which “diacetone acrylamide / dihydrazide” is blended in Table 3 is an emulsion composition obtained by adding 2 parts by weight of diacetone acrylamide as a self-crosslinking compound to the emulsion composition of Example 1. In Example 18, in which 1 part by weight of dihydrazide was added and “2-acetoxyethyl methacrylate / dihydrazide” was blended in Table 3, the emulsion composition of Example 1 was further added with 2-acetoxyethyl methacrylate 2 as a self-crosslinking compound. 1 part by weight of dihydrazide is added to the emulsion composition obtained by adding parts by weight.
Furthermore, as shown in Table 5, as Examples 31 to 39, dipping solutions were prepared by combining various self-crosslinking compounds and various polyfunctional organic compounds, and gloves were prepared.

In Tables 3 and 4, details of each compound are as follows.
Polyoxazoline: “Epocross K-2020E” manufactured by Nippon Shokubai Co., Ltd.
Dihydrazide: “Adipic acid dihydrazide” manufactured by Nippon Kasei Co., Ltd.
Phenol-based methylol compound: “26DMPC” (2,6-dihydroxymethyl-4-methylphenol) manufactured by Asahi Organic Materials Co., Ltd.
Diepoxy compound: “Epolite 100E” (diethylene glycol diglycidyl ether) manufactured by Kyoeisha Chemical Co., Ltd.
Reactive water-based urethane compound: “Elastolon BN69” manufactured by Daiichi Kogyo Seiyaku Co., Ltd. (blocked isocyanate group-containing aqueous polyisocyanate crosslinking agent)
Modified polyamide: “AQ nylon P-95” manufactured by Toray Industries, Inc.
Polyallylamine: “PAA-HCL-01” (allylamine hydrochloride polymer) manufactured by Nitto Bo Medical Co., Ltd.
Acrylic amine polymer: “Polyment NK series, NK-100PM” manufactured by Nippon Shokubai Co., Ltd. (aminoethylated acrylic polymer)
Aziridine compound: “Chemite PZ-33” manufactured by Nippon Shokubai Co., Ltd.
Aqueous methylol melamine compound: “Nikaresin S-176” manufactured by Nippon Carbide Industries Co., Ltd. (melamine-formaldehyde initial condensate)
Silane coupling agent: “A1110” (3-aminopropyltrimethoxysilane) manufactured by Momentive Performance Ateliers Japan

Using each of the above dipping solutions, a glove having a thickness of 0.04 to 0.15 mm was produced by the following dipping method.
That is, the former, which is a glove mold, is washed with a cleaning liquid and then with cold water and dried, and then the coagulant calcium nitrate is dissolved in water in such an amount that the Ca ²⁺ ion concentration is 10% by weight. Soaked for 15 seconds. The former to which the coagulant was adhered was partially dried at 60 ° C. for about 1 minute, and then immersed in each dipping solution at 30 ° C. for 20 seconds. The former was removed from the dipping solution, washed with water, and then immersed in hot water (50 ° C.) for 140 seconds. The former covered with the film of the dipping solution was dried at 120 ° C. for 300 seconds and then maintained at 60 ° C. for 80 seconds, and the resulting gloves were removed from the former.

Tables 1 to 6 show the details of the emulsion compositions of the examples and comparative examples, the glove manufacturing conditions, and the characteristics of the gloves.

Each characteristic of the obtained glove was calculated | required with the following method.
<Acetone soluble component amount>
The gloves were cut and 0.4 g was used as a sample. After precisely weighing the weight (W0) of the sample, it was immersed in a flask containing 70 ml of acetone and heated in a boiling state for 5 hours. Subsequently, the insoluble component which does not melt | dissolve in acetone was taken out, the soluble component melt | dissolved in acetone was moved to another beaker with acetone, it was made to dry in nitrogen atmosphere, and the weight (W1) was measured. The amount of acetone-soluble component was determined from the following formula.
Acetone-soluble component amount (% by weight) = (W1 / W0) × 100

<Toluene weight swelling ratio>
The gloves were immersed in toluene at room temperature, and the weight after 72 hours was divided by the initial weight to determine the weight swelling ratio (%). The calculation method of the weight swelling ratio is as follows.
Sample weight after swelling × 100 / sample weight before swelling (unit:%)

<Crosslink density (calculated from toluene swelling ratio)>
The glove was cut to about 0.2 g, immersed in toluene for 72 hours, and the crosslinking density was calculated by the following formula.
v = V _gom × v ′ = (− V _gom / V) × [ln (1−V _R ) + V _R + μV _R ² ] /
[V _gom ^2/3 × V _R ¹ / _3- (V _R / 2)]
Where v: crosslink density of sample before swelling (mol / cm ³ ), V _gom : rubber volume fraction in sample, v ′: crosslink density of swollen specimen (mol / cm ³ ), V: molecular volume of toluene , V _R : volume fraction of rubber in swollen gel, μ: rubber solvent interaction constant = 0.350.

<Crosslinking density (calculated from measured dynamic viscoelasticity)>
In accordance with JIS K7244-4: 1999 “Plastics—Testing method for dynamic mechanical properties—Part 4: Tensile vibration—Non-resonance method”, the crosslink density of the glove was measured. The measuring apparatus used the viscoelasticity measuring apparatus: RSA-3 by TAINSTRUMENTS, and calculated | required dynamic storage elastic modulus E '(MPa) in 23 degreeC of a glove. By substituting the obtained dynamic storage elastic modulus E ′ (MPa) into the following formula, the crosslinking density n was calculated.
n = E '/ 3RT
Here, n: crosslink density (mol / cm ³ ), R: gas constant (8.314 J / (K · mol)), T: absolute temperature (K), E ′: storage elastic modulus (MPa).

<Molecular weight between cross-linking points (calculated from toluene swelling ratio)>
The molecular weight Mc between crosslinking points of the elastomer of the glove calculated from the toluene swelling rate was calculated by the following Flory-Rehner equation.
Mc = ρν ₁ (ν ₂ / 2−3ν ₂ ^1/2 ) / [ln (1-ν ₂ ) + ν ₂ + χ ₁ ν ₂ ² ]
However, Mc: Molecular weight between cross-linking points (g / mol), ρ: Density (g / cm ³ ), ν ₁ : Molar volume (cm ³ / mol) of solvent (toluene), ν ₂ : Volume swelling ratio (−) , Χ ₁ : represents sp value parameter of solvent and elastomer, respectively.

<Molecular weight between cross-linking points (calculated from measured values of dynamic viscoelasticity)>
The molecular weight Mc between the crosslinking points of the elastomer of the glove, calculated from the dynamic viscoelasticity measurement value, was calculated by the following elastic modulus formula of the crosslinked rubber.
Mc = 2 (1 + μ) ρRT / E
However, Mc: Molecular weight between cross-linking points (g / mol), μ: Poisson's ratio (assuming 0.5), ρ: Density (g / m ³ ), R: Gas constant (8.314 J / K / mol) , T: Absolute temperature (K), E: Elastic modulus (Pa), respectively.

<Flexibility>
The flexibility of the glove was evaluated by tensile properties. Cut a dumbbell No. 5 specimen from the glove and use A &D's TENSILON universal tensile testing machine RTC-1310A, with a test speed of 500 mm / min, a chuck distance of 75 mm, and a gauge distance of 25 mm, tensile strength (MPa), fracture The time elongation (%) and 100% modulus (MPa) were measured.

<Dynamic viscoelasticity measurement>
5 and 6 show measurement examples of the dynamic viscoelasticity of the dry elastomer film in the emulsion composition of Example 1 and the glove obtained in Example 1, respectively. The measurement device is a viscoelasticity measurement device RSA-3 manufactured by TAINSTRUMENTS. The measurement conditions are: measurement mode: tension mode, distance between clamps: 10 mm, measurement frequency: 1 Hz, measurement temperature: −130 to 150 ° C., temperature rise temperature: 2 ° C./min, dynamic strain: 0.1%.

As shown in the table, all of the gloves of the examples were excellent in tensile strength indicating strength and modulus indicating rigidity (stress at 100% elongation). In Example 8, when the amount of added zinc oxide was reduced to half and diethylene glycol was added as much as the polyfunctional organic compound, the tensile strength and rigidity were both excellent.
On the other hand, in Comparative Examples 1 to 3, since XNBR having a small amount of gel component was used, the tensile strength was small and the modulus value was insufficient. A glove (Comparative Example 4) obtained from a commercial product having a small Mooney viscosity and a small amount of gel component was greatly inferior in both tensile strength and modulus value. In the glove (Comparative Example 5) obtained using XNBR with increased Mooney viscosity, the tensile strength and modulus were inferior.

According to the embodiment of the present invention, it is possible to provide a glove that is excellent in strength and rigidity and has no IV type (delay type) allergy.

Claims (11)

1. A glove composed of an elastomer in which a structural unit derived from acrylonitrile, a structural unit derived from an unsaturated carboxylic acid, and a structural unit derived from butadiene are included in the polymer main chain, and a non-sulfur cross-linked structure is formed,
   The glove characterized in that the crosslinked structure is made of an elastomer having a crosslinked structure containing a structural unit derived from a self-crosslinkable compound in a polymer main chain or a crosslinked structure of a non-polymerizable polyfunctional organic compound.
2. The glove according to claim 1, further comprising a cross-linked structure of an aluminum complex or zinc.
3. The glove according to claim 1 or 2, wherein the self-crosslinking compound is a polymerizable monomer containing a polymerizable unsaturated bond and any one functional group selected from an epoxy group, a silanol group, and an isocyanate group.
4. The glove according to any one of claims 1 to 3, wherein the non-polymerizable polyfunctional organic compound includes any one functional group selected from an epoxy group, a silanol group, an isocyanate group, and an oxazoline group.
5. The glove according to claim 4, wherein the non-polymerizable polyfunctional organic compound is any one compound selected from polyepoxide, polyisocyanate, polyoxazoline, and silane coupling agent.
6. The acrylonitrile-derived structural unit is 20 to 35% by weight, the unsaturated carboxylic acid-derived structural unit is 3 to 8% by weight, and the butadiene-derived structural unit is 52 to 76.9% by weight. The glove according to any one of claims 1 to 5, comprising an elastomer having a residual structural unit derived from an agent of 0.1 to 5.0% by weight.
7. The glove according to any one of claims 1 to 6, which has a tensile strength of 25 MPa to 50 MPa, an elongation at break of 400% to 750%, and a 100% modulus of 1.5 MPa to 10 MPa.
8. The glove according to any one of claims 1 to 7, wherein the glove is made of an elastomer that does not contain a crosslinked structure of sulfur as a crosslinking agent and a sulfur compound as a vulcanization accelerator.
9. The glove according to any one of claims 1 to 8, wherein a crosslinking density calculated from a measured value of dynamic viscoelasticity is 1.4 × 10 ^-3 to 5.0 × 10 ^-3 mol / cm ³ .
10. The glove according to any one of claims 1 to 9, wherein the toluene swelling ratio is 240 to 400%.
11. The glove according to any one of claims 1 to 10, wherein the thickness is 0.04 to 0.15 mm.

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