KR101288780B1 - Hydrogenated nitirle-based product, method for hydrogenation of the same - Google Patents

Abstract

The present invention relates to a hydrogenated nitrile-based molding obtained by hydrogenating a carbon-carbon unsaturated double bond on the surface of a nitrile-based molding, and to a method of hydrogenating the same, using a nitrile-based molding prepared by dip molding rather than nitrile-based latex. In addition, the carbon-carbon unsaturated double bond on the surface of the nitrile-based molded product is hydrogenated to change into a single bond, thereby eliminating the sticky property, thereby facilitating the wearability of the nitrile gloves, and improving the chemical resistance.

Description

Hydrogenated nitrile-based moldings, and hydrogenation method thereof

The present invention is hydrogenated nitrile-based molding, specifically, nitrile-based molding prepared by dip molding Acrylonitrile-Butadiene (NBR, Acrylonitrile-Butadiene) latex resin composition, the hydrogenation reaction treatment glove not sticky without conventional chlorination reaction The present invention relates to a hydrogenated nitrile-based molding having excellent chemical resistance and a method for hydrogenation thereof.

Molded products using nitrile rubber are widely used in various fields. Among them, gloves are used in a wide range of fields such as household, food, electronics, and medical fields. In the meantime, rubber gloves made by dip molding natural rubber latex have been used a lot, but the protein contained in the natural rubber causes problems in some users due to allergic reactions such as pain or rash.

In addition, in the existing process, to prevent the gloves from sticking to each other or sticking to each other, the glove is made of halogenated inner and outer surfaces separately, and then washed with water until chlorine residues are removed. The glove was manufactured by the process.

In general, the nitrile gloves before the chlorination process tends to stick due to the carbon-carbon double bonds of butadiene, and tend to stick together, so that the double bonds are replaced by chlorine groups to eliminate the sticky property. It did not stick together.

However, this chlorination process can reduce the shelf life, grip and durability of the glove. In addition, if the chlorination above the optimum point causes a skin tingling, causing a bad odor, and above all damage the gloves by causing defects such as pinholes in the gloves. In addition, there is a disadvantage in that the chemical resistance is weak, and when the organic solvent is handled for a long time there is a problem that the glove is torn and tearing is not preferable.

In order to avoid such a chlorination process, US Patent US 2005/0127552 A1 proposes a method of coating gloves with a hydrogel.

The present inventors have repeatedly studied and surface treated nitrile gloves prepared by a method other than the chlorination process, to provide a method to prevent the sticking of the gloves, which was a problem in the prior art, and to further improve chemical resistance. have.

Accordingly, the present inventors have carried out the nitrile-based molded article prepared by dip molding to convert the carbon-carbon unsaturated double bonds on the surface of the nitrile-based molded article into a single bond by using a hydrogenation method rather than a chlorination process, thereby converting them into single bonds. It is possible to provide a nitrile-based molding having improved chemical resistance as well as facilitating wearability of the nitrile-based molding.

The present invention provides a glove that is easy to wear because it can eliminate the stickiness of the nitrile-based molded product, specifically, the nitrile-based glove by performing hydrogenation rather than a chlorination process as in the present invention, and does not have problems such as skin tingling and chemical resistance. can do.

The hydrogenated nitrile-based molding according to the present invention is characterized by being obtained by substituting a single bond by hydrogenating a carbon-carbon unsaturated double bond on the surface of the molding.

In addition, the hydrogenation method of the nitrile-based molding according to the present invention is characterized in that it comprises the step of hydrogenating the carbon-carbon unsaturated double bond on the surface of the nitrile-based molding to substitute a single bond.

Hereinafter, the present invention will be described in more detail.

The present invention provides a nitrile-based molded product from a nitrile-based rubber latex resin composition, and hydrogenated nitrile-based molded product and its preparation by hydrogenating carbon-carbon double bonds in the unsaturated nitrile-based polymer included in the nitrile-based molded product to hydrogenation. It is about a method.

In the present invention, the hydrogenation treatment may include a diimidization catalyst, the diimide hydrogenation method using the diimidization catalyst can be easily used to hydrogenate the unsaturated polymer as an active hydrogen source, it is simpler than the conventional hydrogenation reaction It is an economical way.

The diimidation catalyst used in the hydrogenation method of the present invention is 0.1 to 20 moles, preferably 0.3 to 10 moles, more preferably 0.5 to 5 moles relative to the moles of carbon-carbon unsaturated double bonds contained in the nitrile-based molding. Reducing agent; 0.1 to 20 moles, preferably 0.3 to 10 moles, more preferably 0.5 to 5 moles of oxidant and 0.001 to 3 moles to moles of carbon-carbon unsaturated double bonds, preferably It is composed of 0.005 ~ 1 mol, more preferably 0.01 ~ 0.5 mol of the reaction accelerator, when the ratio of each component of the catalyst is out of the range, the hydrogenation efficiency is lowered or the gel content is out of the proper range, It is not preferable because of the problem of stickiness and inferior chemical resistance.

The diimide catalyst obtained from the reaction of the reducing agent and the oxidant plays a role of hydrogenating the carbon-carbon double bond included in the nitrile-based molded product of the present invention to convert it into a single bond, as shown in the following Scheme 1.

(Scheme 1)

N ₂ H ₄ + H ₂ O ₂ + -HC = CH- → N ₂ + -H ₂ C-CH _2- + 2H ₂ O

The diimidation catalyst is composed of a reducing agent / oxidant / reaction accelerator, it can be used in the form of an aqueous solution dissolved in water, in the case of the oxidant solution may be added in a batch, or continuously in the form of droplets droplets.

In addition, the reducing agent constituting the diimidization catalyst includes hydrazine and hydrazine derivatives, for example, at least one similar group selected from the group consisting of hydrazine, hydrazine hydrate, hydrazine acetate, hydrazine sulfate and hydrazine hydrochloride. It also includes materials that can exhibit properties. Preferably hydrazine and hydrazine hydrate are used.

In addition, the oxidizing agent constituting the diimidization catalyst can exhibit properties similar to those of the hydrogen peroxide such as air, oxygen, ozone, PEROXIDE, HYDROPEROXIDE, iodine, iodide, hypochlorite, etc. Includes up to Preferably, suitable oxidants can be selected and used among peroxides and hydroperoxides. Most preferably HYDROGEN PEROXIDE is used.

In addition, the reaction accelerator constituting the diimidation catalyst serves to promote the hydrogenation reaction, and may be selected from the group consisting of borate, peroxyborate, and boric acid (H ₃ BO ₃ ). Preferably boric acid is used.

In the present invention, the nitrile-based molded article prepared by the dip coating method, specifically, a nitrile-based glove is applied to hydrogenated unsaturated carbon-carbon double bonds located on the surface of the nitrile glove to be converted into a single bond. Hydrogenation of the nitrile gloves by the diimide method in the same manner as described above eliminates the sticky properties without using the usual chlorination process to improve the wearability, prevent them from sticking together, and to obtain nitrile gloves with increased chemical resistance. Can be.

Hereinafter, the process of preparing the hydrogenated nitrile-based molding according to the present invention will be described in detail.

First, carboxylic acid-modified nitrile copolymer latex is prepared by adding an emulsifier, a polymerization initiator, a molecular weight modifier, and other additives to a conjugated diene monomer, an ethylenically unsaturated nitrile monomer, an ethylenically unsaturated acid monomer, and other monomers. do.

Specific examples of the conjugated diene monomer include a group consisting of 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-butadiene, 1,3-pentadiene and isoprene At least one selected from among them, of which 1,3-butadiene and isoprene are preferable, and 1,3-butadiene is most preferably used.

The ethylenically unsaturated nitrile monomer is at least one selected from the group consisting of acrylonitrile, methacrylonitrile, fumaronitrile, α-chloronitrile, and α-cyano ethyl acrylonitrile, wherein acrylonitrile and Preference is given to methacrylonitrile, in particular acrylonitrile being most preferably used.

In addition, the ethylenically unsaturated acid monomer is an ethylenically unsaturated monomer containing at least one acidic group selected from the group consisting of a carboxyl group, a sulfonic acid group, and an acid anhydride group, for example, acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, or the like. Ethylenically unsaturated carboxylic acid monomers; Polycarboxylic acid anhydrides such as maleic anhydride and citraconic anhydride; Ethylenically unsaturated sulfonic acid monomers such as styrene sulfonic acid; And ethylenically unsaturated polycarboxylic acid partial ester monomers such as monobutyl fumarate, monobutyl maleate, and mono-2-hydroxypropyl maleate. Of these, ethylenically unsaturated carboxylic acid monomers are preferably used, and methacrylic acid is particularly preferable. Such ethylenically unsaturated acid monomers may be used in the form of alkali metal salts or ammonium salts.

The carboxylic acid-modified nitrile copolymer according to the present invention may optionally further include other ethylenically unsaturated monomers copolymerizable with the ethylenically unsaturated nitrile monomer and the ethylenically unsaturated acid monomer, specifically styrene and alkyl styrene. And vinyl aromatic monomers selected from the group consisting of vinyl naphthalene; Fluoroalkyl vinyl ethers such as fluoro ethyl vinyl ether; (Meth) acrylamide, N-methylol (meth) acrylamide, N, N-dimethylol (meth) acrylamide, N-methoxy methyl (meth) acrylamide, and N-propoxy methyl (meth) acrylamide Ethylenically unsaturated amide monomers selected from the group consisting of: Vinyl pyridine; Vinylnorbornene; Non-conjugated diene monomers such as dicyclopentadiene and 1,4-hexadiene; Methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, trifluoroethyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, dibutyl maleate, difumaric acid Butyl, diethyl maleate, methoxy methyl (meth) acrylate, ethoxy ethyl (meth) acrylate, methoxy ethoxy ethyl (meth) acrylate, cyano methyl (meth) acrylate, 2-cyano ethyl (meth) acrylate, (Meth) acrylic acid 1-cyanopropyl, (meth) acrylic acid 2-ethyl-6-cyanohexyl, (meth) acrylic acid 3-cyanopropyl, (meth) acrylic acid hydroxyethyl, (meth) acrylic acid hydroxyethyl, Group consisting of ethylenically unsaturated carboxylic ester monomers selected from the group consisting of (meth) acrylic acid hydroxy propyl, glycidyl (meth) acrylate, and dimethylamino ethyl (meth) acrylate Use one or more selected from.

The monomer composition as described above and emulsion polymerization by adding an emulsifier, a polymerization initiator, a molecular weight regulator, and the like are prepared by emulsion polymerization. The emulsifier, the polymerization initiator, the molecular weight regulator, and the like are used for preparing a carboxylic acid-modified nitrile copolymer latex. In general, examples thereof are omitted.

Then, the carboxylic acid-modified nitrile-based copolymer latex is included in the latex composition for dip molding to dip molding to prepare a nitrile-based molding as a final product.

In the present invention, the process of preparing a nitrile-based molded product by dip molding from the latex composition for dip molding does not significantly deviate from the conventional method, and thus a detailed description thereof will be omitted.

The nitrile-based molded product obtained as described above is hydrogenated using the diimidation catalyst of the present invention to produce a hydrogenated nitrile-based molded product.

The diimidation catalyst used in the hydrogenation process has a catalyst configuration as described above, the hydrogenation method is 0 ℃ to 250 ℃, preferably 20 ℃ to 150 ℃, more preferably 40 ℃ to 100 ℃ 30 minutes It is preferable to carry out for 24 hours, preferably 40 minutes-18 hours, more preferably 50 minutes-12 hours, since it can improve the hydrogenation reaction efficiency. The hydrotreated dip molding is washed with excess water to obtain a non-sticky hydrogenated nitrile based molding.

The process according to the invention can be used for any latex article which can be produced by the technically known dip-molding methods. Specifically, it can be applied to dip molded latex articles selected from health care products such as surgical gloves, inspection gloves, condoms, catheters or various kinds of industrial and household gloves.

Hereinafter, the present invention will be described in detail with reference to examples.

≪ Example 1 >

(Preparation of latex resin composition)

21 parts by weight of acrylonitrile, 74 parts by weight of 1,4-butadiene, 5 parts by weight of methacrylic acid, 0.5 parts by weight of tert-dodecyl mercaptan, 2.3 parts by weight of sodium dodecylbenzenesulfonate, 140 parts by weight of water After the addition, the temperature was raised to 40 ° C. to initiate polymerization. When the conversion reached 65%, the temperature was elevated to 70 ° C to proceed the polymerization. When the conversion reached 94%, 0.2 part by weight of sodium dimethyldithiocarbamate was added to terminate the polymerization. The unreacted monomer was removed through a deodorizing process, and ammonia water, an antioxidant, an antifoaming agent, and the like were added to obtain a carboxylic acid-modified nitrile copolymer latex having a solid content of 44.5% and pH 8.0.

A 5% potassium hydroxide solution and an appropriate amount of secondary distilled water were added to the latex to obtain a composition for dip molding having a solid concentration of 30% and a pH of 9.5.

(Manufacture of deep moldings)

A coagulant solution was prepared by mixing 22 parts by weight calcium nitrate, 69.5 parts by weight methanol, 8 parts by weight calcium carbonate, and 0.5 parts by weight wetting agent (Teric 320 produced by Huntsman Corporation, Australia). The hand-shaped ceramic mold was immersed in this solution for 1 minute, taken out, and dried at 70 ° C. for 3 minutes to apply a coagulant to the hand-shaped mold.

Next, the mold to which the coagulant was applied was immersed in the dip molding composition for 1 minute, pulled up, dried at 70 ° C. for 1 minute, and leached for 3 minutes in water or hot water. The mold was dried at 70 ° C. for 3 minutes and crosslinked at 125 ° C. for 20 minutes.

(Hydrogenation reaction)

The cross-linked dip molding layer contains 24 g of hydrazine (1.5 moles per mole of C = C in NBR latex), 25.5 g of hydrogen peroxide (1.5 moles per mole of C = C in NBR latex), 1.9 g of boric acid (per mole of C = C in NBR latex) 0.06 mol) was immersed in an aqueous solution dissolved in water at 60 ° C to hydrogenate the surface of the glove for 2 hours. The glove surface was washed with excess water and then the crosslinked dip molding layer was peeled off from the hand-shaped mold to obtain a glove-shaped dip molding.

<Example 2>

In Example 1, 57.6 g of hydrazine (3.6 mol of C = C moles in NBR latex), 69.7 g of hydrogen peroxide (4.1 moles of C = C moles in NBR latex), 6.2 g of boric acid (0.2 moles of C = C moles in NBR latex) The dip molding in the form of a glove was prepared in the same manner except that moles) were used.

&Lt; Comparative Example 1 &

Dip moldings in the form of gloves were prepared in the same manner except that the hydrogenation process was not performed in Example 1.

Comparative Example 2

In the same manner as in Example 1, except that the chlorination reaction was performed for 30 min in a 500 ppm solution of chlorine concentration prepared by mixing HCl solution and NaOCl solution instead of the hydrogenation reaction, a dip-shaped molded article was prepared in the same manner.

The physical properties of the dip moldings obtained in Examples and Comparative Examples were evaluated as follows, and the results are shown in Table 1 below.

1) C = C bond strength change

Changes in C = C bond strength with time of hydrogenation were analyzed by FT-IR spectroscopy. This is because, as the hydrogenation reaction proceeds, the carbon-carbon double bond is changed into a single bond, and the degree of the hydrogenation reaction can be inferred as the strength of the double bond is weakened.

2) Glove Stickiness

The prepared gloves were stored at 70 ° C. for one week, and then measured by the five-point method from 1 (non-sticky) to 5 (sticky) to determine whether the gloves can be easily worn without stickiness and sticking to each other.

3) chemical resistance

Each glove was cut to a diameter of 2.5 cm and then immersed in a cyclohexanone solution for 30 minutes to measure the degree of change in diameter of the circular glove to measure the chemical resistance to the solvent.

Relative Intensity of C = C Peak Intensity Glove Stickiness Chemical resistance Example 1 10.9 One 5cm Example 2 10.7 One 5.2 cm Comparative Example 1 12.7 5 15cm Comparative Example 2 10.8 One 13 cm

As shown in the results of Table 1 above, the carbon-carbon unsaturated double bonds on the surface of the nitrile-based molded product were replaced with hydrogen and changed into a single bond through hydrogenation as in Examples 1 and 2 of the present invention so that the C = C peak intensity was relatively high. It was confirmed that it was weakened, almost no glove stickiness, and excellent chemical resistance.

However, in the case of Comparative Example 1, which did not undergo the hydrogenation reaction as in the present invention, the gloves were sticky, and the chemical resistance was also poor. In addition, the glove of Comparative Example 2 manufactured by the conventional chlorination process has a small C = C bond strength and little glove stickiness, but chemical resistance was not good.

Therefore, when performing the hydrogenation reaction as in the present invention, it can be confirmed that both excellent in terms of wearing and safety of the glove without various problems generated in the conventional chlorination process.

Claims (11)

Preparing a nitrile-based molding by dip molding from a nitrile-based resin composition; And
A method for producing a hydrogenated nitrile-based molding comprising the step of hydrogenating a carbon-carbon unsaturated double bond on the surface of the nitrile-based molding to substitute a single bond,
The hydrogenation step may include a reducing agent comprising a hydrazine and a hydrazine derivative; At least one oxidizing agent selected from the group consisting of air, oxygen, ozone, PEROXIDE, HYDROPEROXIDE, iodine, iodide, hypochlorite; And a hydrogenated nitrile-based molding product characterized in that it is hydrogenated using a diimidation catalyst comprising at least one reaction promoter selected from the group consisting of borate, peroxyborate, and boric acid (H ₃ BO ₃ ). Manufacturing method. delete delete delete delete The method of claim 1,
The hydrogenation step comprises a diimidation catalyst comprising 0.1 to 20 moles of reducing agent, 0.1 to 20 moles of oxidant, and 0.001 to 3 moles of reaction promoter relative to the moles of carbon-carbon unsaturated double bonds in the nitrile-based molding. A process for producing a hydrogenated nitrile molded article, characterized in that it is subjected to a hydrogenation treatment. The method of claim 1,
The hydrogenation treatment is a method for producing a hydrogenated nitrile-based molding, characterized in that carried out at 0 ℃ ~ 250 ℃. The method of claim 1,
The hydrogenation process is a method for producing a hydrogenated nitrile-based molding, characterized in that carried out for 30 minutes to 24 hours. The method of claim 1,
The nitrile-based molding is a method for producing a hydrogenated nitrile-based molding, characterized in that the nitrile-based gloves. delete delete