WO2016140043A1 - ディップ成形用合成イソプレン重合体ラテックス、ディップ成形用組成物およびディップ成形体 - Google Patents
ディップ成形用合成イソプレン重合体ラテックス、ディップ成形用組成物およびディップ成形体 Download PDFInfo
- Publication number
- WO2016140043A1 WO2016140043A1 PCT/JP2016/054213 JP2016054213W WO2016140043A1 WO 2016140043 A1 WO2016140043 A1 WO 2016140043A1 JP 2016054213 W JP2016054213 W JP 2016054213W WO 2016140043 A1 WO2016140043 A1 WO 2016140043A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- isoprene polymer
- synthetic isoprene
- dip
- latex
- weight
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F36/00—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds
- C08F36/02—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds
- C08F36/04—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds conjugated
- C08F36/08—Isoprene
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
- B29C41/02—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of definite length, i.e. discrete articles
- B29C41/14—Dipping a core
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J3/00—Processes of treating or compounding macromolecular substances
- C08J3/02—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques
- C08J3/03—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques in aqueous media
- C08J3/05—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques in aqueous media from solid polymers
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J3/00—Processes of treating or compounding macromolecular substances
- C08J3/02—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques
- C08J3/03—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques in aqueous media
- C08J3/07—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques in aqueous media from polymer solutions
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/30—Sulfur-, selenium- or tellurium-containing compounds
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/0008—Organic ingredients according to more than one of the "one dot" groups of C08K5/01 - C08K5/59
- C08K5/0025—Crosslinking or vulcanising agents; including accelerators
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/36—Sulfur-, selenium-, or tellurium-containing compounds
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L9/00—Compositions of homopolymers or copolymers of conjugated diene hydrocarbons
- C08L9/10—Latex
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2007/00—Use of natural rubber as moulding material
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2309/00—Characterised by the use of homopolymers or copolymers of conjugated diene hydrocarbons
Definitions
- the present invention relates to a synthetic isoprene polymer latex for dip molding, a composition for dip molding, and a dip molded body. More specifically, the present invention relates to a synthetic isoprene polymer latex for dip molding having a specific particle size distribution, a dip molding composition containing the latex, and a dip molded body obtained by dip molding the composition.
- a dip molding composition containing a latex of natural rubber is dip-molded to obtain a dip-molded body used in contact with a human body such as a nipple, a balloon, a glove, a balloon, and a sack.
- natural rubber latex contains a protein that causes allergic symptoms in the human body
- studies using synthetic isoprene polymers in place of natural rubber have been conducted, and the amount used has been increasing year by year.
- Patent Document 1 discloses a method for producing a synthetic isoprene polymer latex in which a synthetic isoprene polymer is dissolved in a solvent, emulsified with a surfactant, further desolvated, and centrifuged.
- a synthetic isoprene polymer is dissolved in a solvent, emulsified with a surfactant, further desolvated, and centrifuged.
- the latex produced by this method has a high viscosity when the concentration is increased, there is a possibility that troubles such as the latex not flowing in the apparatus may occur.
- An object of the present invention is to provide a synthetic isoprene polymer latex for dip molding that can suppress an increase in viscosity even when the concentration is increased. It is another object of the present invention to provide a dip-forming composition containing the latex and a dip-molded body obtained by dip-molding the composition.
- the present inventors have found that a synthetic isoprene polymer latex containing a synthetic isoprene polymer solution-polymerized using an alkyllithium polymerization catalyst, the particle size distribution of which falls within a predetermined range.
- the latex thus controlled has been found to be able to suppress an increase in viscosity to a predetermined value or less even when the concentration is increased, and the present invention has been completed.
- the present invention it is possible to provide a synthetic isoprene polymer latex for dip molding that can suppress an increase in viscosity even when the concentration is increased. Furthermore, the composition for dip molding containing this latex and the dip molding obtained by dip molding this composition can be provided.
- the synthetic isoprene polymer latex for dip molding of the present invention is a synthetic isoprene polymer latex for dip molding containing a synthetic isoprene polymer solution-polymerized using an alkyllithium polymerization catalyst, and the mode diameter of the latex particle diameter is Brookfield viscosity (V 56 ) when the ratio to the median diameter (mode diameter / median diameter) is 0.8 or more and the solid concentration is 56% and Brookfield viscosity when the solid concentration is 66% (V the difference between V 66) (V 66 -V 56 ) is not more than 200 mPa ⁇ s.
- V 56 Brookfield viscosity
- the synthetic isoprene polymer used in the present invention is obtained by polymerizing isoprene. Further, the synthetic isoprene polymer used in the present invention may be a copolymer of another ethylenically unsaturated monomer copolymerizable with isoprene.
- the content of isoprene units in the synthetic isoprene polymer is flexible, and it is easy to obtain a dip-molded product excellent in tensile strength. Therefore, it is preferably 70% by weight or more, more preferably 90%, based on all monomer units. % By weight or more, more preferably 95% by weight or more, particularly preferably 100% by weight (homopolymer of isoprene).
- Examples of other ethylenically unsaturated monomers copolymerizable with isoprene include conjugated diene monomers other than isoprene such as butadiene, chloroprene and 1,3-pentadiene; acrylonitrile, methacrylonitrile, fumaronitrile, ⁇ - Ethylenically unsaturated nitrile monomers such as chloroacrylonitrile; vinyl aromatic monomers such as styrene and alkylstyrene; methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, (meth) And ethylenically unsaturated carboxylic acid ester monomers such as 2-ethylhexyl acrylate; crosslinkable monomers such as divinylbenzene, diethylene glycol di (meth) acrylate, and pentaerythritol (meth) acrylate.
- the other ethylenically unsaturated monomer copolymerizable with these isoprenes may be used individually by 1 type, and may use multiple types together.
- (meth) acrylate means both “acrylate” and “methacrylate”.
- the isoprene unit in the synthetic isoprene polymer includes a cis bond unit (1,4-cis structure), a trans bond unit (1,4-trans structure), a 1,2-vinyl bond unit, 3 depending on the bond state of isoprene.
- a cis bond unit (1,4-cis structure
- a trans bond unit (1,4-trans structure
- a 1,2-vinyl bond unit 3 depending on the bond state of isoprene.
- 4-vinyl bond units There are four types of 4-vinyl bond units.
- the content (cis content) of the cis bond units (1,4-cis structure) in the isoprene units contained in the synthetic isoprene polymer is all from the viewpoint of improving the tensile strength of the resulting dip-molded product. It is 60% by weight or more, preferably 70% by weight or more based on the isoprene unit.
- the weight average molecular weight of the synthetic isoprene polymer is 10,000 to 5,000,000, preferably 500,000 to 5,000,000, particularly preferably 800 in terms of standard polystyrene by gel permeation chromatography analysis. , 4,000 to 4,000,000.
- the weight average molecular weight of the synthetic isoprene polymer is in the above range, the phenomenon that the tensile strength of the dip-molded product is reduced because the weight average molecular weight is excessively small, and the weight average molecular weight is The phenomenon that the latex of the synthetic isoprene polymer becomes difficult to produce due to being excessively large can be suppressed.
- the polymer Mooney viscosity [ML 1 + 4 , 100 ° C.] of the synthetic isoprene polymer is preferably 50 to 80, more preferably 60 to 80, and still more preferably 70 to 80.
- the synthetic isoprene polymer can be obtained by solution polymerization of isoprene in an inert polymerization solvent using a polymerization catalyst.
- a polymerization catalyst such as n-butyllithium or sec-butyllithium is used as the polymerization catalyst. Of these, n-butyllithium is preferably used.
- an alkyl lithium polymerization catalyst By using an alkyl lithium polymerization catalyst, the polymerization reaction can be carried out at a high polymerization conversion rate.
- a polymerization accelerator in addition to the polymerization catalyst in the polymerization of the synthetic isoprene polymer.
- the polymerization accelerator tetramethylethylenediamine (TMEDA), hexamethylphosphoramide (HMPA), N, N′-dimethylpropylene urea (DMPU), dimethyl sulfoxide (DMSO), or the like can be used.
- TMEDA tetramethylethylenediamine
- HMPA hexamethylphosphoramide
- DMPU N, N′-dimethylpropylene urea
- DMSO dimethyl sulfoxide
- the synthetic isoprene polymer latex for dip molding of the present invention (hereinafter sometimes simply referred to as “synthetic isoprene polymer latex”) comprises the synthetic isoprene polymer.
- a synthetic isoprene polymer having a high content of cis-bond units in the isoprene unit can be used, and from the viewpoint of obtaining a dip-molded article having excellent tensile strength, for example, organic
- a synthetic isoprene polymer solution or fine suspension dissolved or finely dispersed in a solvent is emulsified in water in the presence of a surfactant, and an organic solvent is removed as necessary to produce a synthetic isoprene polymer latex. The method is preferred.
- the synthetic isoprene polymer used in the present invention can be obtained by solution polymerization of isoprene in an inert polymerization solvent using an alkyllithium polymerization catalyst such as n-butyllithium or sec-butyllithium as described above. . And it is preferable to use the polymer solution of the obtained synthetic isoprene polymer as it is.
- impurities such as a residue of the polymerization catalyst remaining in the polymer solution may be removed.
- organic solvent used in the above production method examples include aromatic hydrocarbon solvents such as benzene, toluene, and xylene; alicyclic hydrocarbon solvents such as cyclopentane, cyclopentene, cyclohexane, and cyclohexene; and pentane, hexane, and heptane.
- aromatic hydrocarbon solvents such as benzene, toluene, and xylene
- alicyclic hydrocarbon solvents such as cyclopentane, cyclopentene, cyclohexane, and cyclohexene
- pentane, hexane, and heptane examples include aromatic hydrocarbon solvents such as benzene, toluene, and xylene; alicyclic hydrocarbon solvents such as cyclopentane, cyclopentene, cyclohexane, and cyclohexene; and pentane, hexan
- aromatic hydrocarbon solvents alicyclic hydrocarbon solvents, and aliphatic hydrocarbon solvents are preferable, and cyclohexane, toluene, n-hexane, and pentane are particularly preferable.
- the amount of the organic solvent used is preferably 2,000 parts by weight or less, more preferably 20 to 1,500 parts by weight with respect to 100 parts by weight of the synthetic isoprene polymer.
- the synthetic isoprene polymer latex of the present invention has a ratio of mode diameter to median diameter (mode diameter / median diameter) of 0.8 or more, preferably 0.9 or more and 1.8 or less, in the particle diameter.
- mode diameter / median diameter 0.8 or more, preferably 0.9 or more and 1.8 or less, in the particle diameter.
- it is 1.0 or more and 1.5 or less, Most preferably, it is 1.0 or more and 1.1 or less.
- this value is less than 0.8, the viscosity becomes too high when the solid content concentration of the latex is 66% or more.
- this value exceeds 2.0 the large particle diameter side tends to become unstable.
- the mode diameter means a particle diameter having the highest particle existence probability, and shows a maximum value in a particle diameter distribution curve in which the frequency of the existence of individual particle diameters is plotted against the logarithm of the particle diameter. It is the particle size.
- the median diameter is a particle diameter at a cumulative 50% point in a particle diameter distribution obtained on a volume basis from the small particle diameter side (oversize). Sometimes referred to as 50% average particle size.
- the method for adjusting the ratio of mode diameter to median diameter (mode diameter / median diameter) to 0.8 or more is not particularly limited.
- the interface during emulsification Examples include the type of activator, the amount used, the addition method (collective addition, divided addition, etc.) and the method of changing the emulsification conditions of the emulsifier.
- the type of surfactant during emulsification is not particularly limited, but sodium or potassium salts of fatty acids such as lauric acid, myristic acid, palmitic acid, oleic acid, linolenic acid, and rosin acid are preferred. Among these, rosinate is most preferable from the viewpoint of ease of handling, availability, safety, and the like.
- Anionic surfactants such as alkylbenzene sulfonates such as sodium dodecylbenzenesulfonate, higher alcohol sulfates and alkylsulfosuccinates; Cations such as alkyltrimethylammonium chloride, dialkyldimethylammonium chloride and alkylbenzyldimethylammonium chloride
- Surfactant ⁇ , ⁇ -unsaturated carboxylic acid sulfoester, ⁇ , ⁇ -unsaturated carboxylic acid sulfate ester, Copolymerizable surfactants such as sulfo alkyl aryl ether; and the like.
- These surfactants may be used individually by 1 type, and may use 2 or more types together.
- the amount of surfactant used is not particularly limited.
- the amount is preferably 3 to 30 parts by weight, more preferably 5 to 20 parts by weight, particularly preferably 7 to 15 parts by weight, most preferably 100 parts by weight of the synthetic isoprene polymer. 8 to 10 parts by weight.
- the amount of the surfactant used is in the above range, the phenomenon that the amount of agglomerates increases because the amount used is excessively small, and foaming easily occurs because the amount used is excessively large. It is possible to suppress the phenomenon that problems occur during dip molding.
- the addition method of the surfactant is not particularly limited, and even if it is added to water and / or an organic solvent solution or fine suspension of the synthetic isoprene polymer in advance, it is added to the emulsion during the emulsification operation. They may be added, or they may be added all at once or dividedly. Examples of the method of adding the surfactant in a divided manner include a method in which the amount of the surfactant used is reduced at the initial stage of emulsification and the surfactant is increased during the emulsification.
- the method of reducing the amount of surfactant used in the initial stage of emulsification and increasing the amount of surfactant in the middle of emulsification is a mode diameter method in which a latex is obtained by gradually adding an isoprene polymer solution to an aqueous surfactant solution to obtain an emulsion. / This is an effective means to make the median diameter a preferable category.
- the method for changing the emulsification conditions of the emulsifier is not particularly limited, and a method for selecting an optimal combination of the teeth of the emulsifier (generator), a method for changing the hole diameter and gap of the rotor / stator of the emulsifier , A method of changing the shearing force during emulsification, a method of blending one having a short emulsification time and one having a long emulsification time, and changing the ratio of water and the synthetic isoprene polymer.
- a method of selecting an optimal combination of the teeth (generator) of the emulsifier and a method of changing the hole diameter and gap of the rotor / stator of the emulsifier are preferable.
- any one of these types of surfactant during emulsification, amount used, addition method (batch addition, divided addition, etc.) and change in emulsification conditions may be performed, or two or more may be performed in combination. Also good.
- the amount of water used in the method for producing the synthetic isoprene polymer latex is preferably 50 to 5,000 parts by weight, more preferably 100 to 3,000 parts by weight with respect to 100 parts by weight of the synthetic isoprene polymer.
- Examples of the water used include hard water, soft water, ion exchange water, distilled water, and zeolite water.
- An apparatus for emulsifying an organic solvent solution or fine suspension of a synthetic isoprene polymer in water in the presence of a surfactant is not particularly limited as long as it is generally commercially available as an emulsifier or a disperser. .
- emulsifier examples include a batch type emulsifier such as trade name: homogenizer (manufactured by IKA), trade name: polytron (manufactured by Kinematica), trade name: TK auto homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), etc.
- a batch type emulsifier such as trade name: homogenizer (manufactured by IKA), trade name: polytron (manufactured by Kinematica), trade name: TK auto homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), etc.
- TK Pipeline Homomixer manufactured by Koki Kogyo Kogyo Co., Ltd.
- Product Name: Trigonal Wet Fine Crusher Product name: Cavitron (manufactured by Eurotech), product name: Milder (manufactured by Taiheiyo Kiko Co., Ltd.), product name: Fine Flow Mill (manufactured by Taiheiyo Kiko Co., Ltd.), etc.
- Microfluidizer manufactured by Mizuho Kogyo Co., Ltd.
- Nanomizer manufactured by Nanomizer Co., Ltd.
- APV Gaurin manufactured by Gaulin Co., Ltd.
- Membrane emulsifiers such as an emulsifier (made by Chilling Industries Co., Ltd.)
- the conditions of the emulsification operation by the emulsification apparatus are not particularly limited, and the treatment temperature, the treatment time, and the like may be appropriately selected so as to obtain a desired dispersion state.
- a synthetic isoprene polymer latex by removing the organic solvent from the emulsion obtained through the emulsification operation.
- the method for removing the organic solvent from the emulsion is not particularly limited, and methods such as vacuum distillation, atmospheric distillation, steam distillation, and centrifugation can be employed.
- a concentration operation may be performed by a method such as vacuum distillation, atmospheric distillation, centrifugation, membrane concentration, etc. .
- the solid content concentration of the synthetic isoprene polymer latex is preferably 30 to 70% by weight, more preferably 40 to 70% by weight.
- the solid content concentration is in the above range, since the solid content concentration is excessively low, the phenomenon that the synthetic isoprene polymer particles are separated when the synthetic isoprene polymer latex is stored can be suppressed. Further, since the solid content concentration is excessively high, it is possible to suppress the phenomenon that the synthetic isoprene polymer particles are aggregated to generate a coarse aggregate.
- the synthetic isoprene polymer latex of the present invention has a difference (V 66 ⁇ ) between the Brookfield viscosity (V 56 ) when the solid content concentration is 56% and the Brookfield viscosity (V 66 ) when the solid content concentration is 66%.
- V 56 is 200 mPa ⁇ s or less, more preferably 150 mPa ⁇ s or less.
- this difference (V 66 -V 56 ) exceeds 200 mPa ⁇ s, the latex becomes difficult to flow in the concentrator, and it is necessary to stop the concentration at a low concentration.
- the viscosity in the present invention is a viscosity value measured at 25 ° C. using a Brookfield viscometer (hereinafter sometimes referred to as “B-type viscometer”).
- the method include a method for adjusting the type and amount of a water-soluble substance such as a surfactant and a thickener, and a method for adjusting the pH of the latex.
- the surfactants exemplified in the description of the particle diameter control described above can be used.
- these surfactants sodium or potassium salts of fatty acids such as lauric acid, myristic acid, palmitic acid, oleic acid, linolenic acid and rosin acid are preferred.
- the amount of these surfactants used the optimum amount varies depending on the type of the surfactant, so it cannot be generally stated, but in the case of sodium rosinate and potassium rosinate, for 100 parts by weight of the synthetic isoprene polymer. 3 parts by weight or less is preferable, and 2 parts by weight or less is more preferable.
- the thickener is not particularly limited, and examples thereof include cellulosic polymers such as carboxymethylcellulose, methylcellulose, and hydroxypropylcellulose, and ammonium salts and alkali metal salts thereof; (modified) poly (meth) acrylic acid and ammonium salts thereof.
- (modified) polyvinyl alcohols such as polyvinyl alcohol, acrylic acid or copolymers of acrylate and vinyl alcohol, maleic anhydride or maleic acid or copolymers of fumaric acid and vinyl alcohol; polyethylene glycol, Examples thereof include polyethylene oxide, polyvinyl pyrrolidone, modified polyacrylic acid, oxidized starch, phosphate starch, casein, various modified starches, acrylonitrile-butadiene copolymer hydride, and the like. Among these, it is preferable to use carboxymethylcellulose, ammonium salt of carboxymethylcellulose, and alkali metal salt.
- “(modified) poly” means “unmodified poly” or “modified poly”.
- the amount of thickener used is preferably 1 part by weight or less, more preferably 0.1 part by weight or less, based on 100 parts by weight of the synthetic isoprene polymer.
- Examples of the pH adjuster for adjusting the pH of the latex include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide; alkali metal carbonates such as sodium carbonate and potassium carbonate; alkali metals such as sodium hydrogen carbonate. Ammonium; organic amine compounds such as trimethylamine and triethanolamine; and the like, and alkali metal hydroxides or ammonia are preferred.
- the pH value of the latex is preferably 7 to 12, more preferably 8 to 11, and most preferably 9 to 10. In addition, what is necessary is just to adjust to the optimal pH value according to the characteristic of water-soluble substances, such as surfactant used and a thickener.
- the volume average particle diameter of latex particles (synthetic isoprene polymer particles) in the synthetic isoprene polymer latex is preferably 0.5 to 10 ⁇ m, more preferably 0.5 to 3 ⁇ m, and particularly preferably 0.5 to 2 ⁇ m. It is.
- the volume average particle diameter of the latex particles is in the above range, the volume average particle diameter is excessively small, and thus the phenomenon that the latex viscosity becomes too high and difficult to handle can be suppressed. Since the diameter is excessively large, a phenomenon that a film is formed on the surface of the latex when the synthetic isoprene polymer latex is stored can be suppressed.
- the maximum particle size of the latex particles is usually 30 ⁇ m or less, preferably 10 ⁇ m or less, more preferably 8 ⁇ m or less, and most preferably 7 ⁇ m or less.
- the ratio of the maximum particle size to all particles is usually 1% or less, preferably 0 0.5% or less, more preferably 0.1% or less, and most preferably 0.01% or less.
- the electrical conductivity of the synthetic isoprene polymer latex is preferably 0.5 mS / cm to 2.0 mS / cm.
- the electrical conductivity is excessively small, so that a phenomenon that a large amount of aggregates are generated at the time of emulsification or concentration can be suppressed, and since the electrical conductivity is excessively large, It is possible to suppress the phenomenon that foaming becomes intense at the time of solvent removal, or foaming is intense at the time of transferring or blending the dip molding composition, and defects such as pinholes are generated in the resulting dip molding.
- the conductivity is a value measured at a measurement temperature of 25 ° C. using a conductivity meter (trade name: SG78-FK2) manufactured by METLER TOLEDO.
- the total content of the alicyclic hydrocarbon solvent, the aliphatic hydrocarbon solvent, and the aromatic hydrocarbon solvent in the synthetic isoprene polymer latex is preferably 500 ppm by weight or less.
- cyclohexane is preferable as the alicyclic hydrocarbon solvent
- normal pentane is preferable as the aliphatic hydrocarbon solvent
- toluene is preferable as the aromatic hydrocarbon solvent. If the total content of the alicyclic hydrocarbon solvent, aliphatic hydrocarbon solvent and aromatic hydrocarbon solvent, especially the total content of cyclohexane, pentane and toluene, is too high, the odor of the composition for dip molding tends to be tight. is there.
- the total content of the alicyclic hydrocarbon solvent, the aliphatic hydrocarbon solvent and the aromatic hydrocarbon solvent can be measured by a generally usable measurement method such as a gas chromatography method.
- the synthetic isoprene polymer latex usually contains a pH adjuster, an antifoaming agent, a preservative, a crosslinking agent, a chelating agent, an oxygen scavenger, a dispersant, an anti-aging agent, etc.
- An agent may be blended.
- the dip molding composition of the present invention comprises the above-described synthetic isoprene polymer latex for dip molding, a vulcanizing agent, and a vulcanization accelerator. Moreover, the other component may be included as needed.
- vulcanizing agent examples include powdered sulfur, sulfur white, precipitated sulfur, colloidal sulfur, surface-treated sulfur, insoluble sulfur, and the like; sulfur chloride, sulfur dichloride, morpholine disulfide, alkylphenol disulfide, N, N'- Sulfur-based vulcanizing agents such as dithio-bis (hexahydro-2H-azepinone-2), phosphorus-containing polysulfide, polymer polysulfide, 2- (4′-morpholinodithio) benzothiazole and the like can be used. Of these, sulfur is preferably used. These vulcanizing agents may be used alone or in combination of two or more.
- the use amount of the vulcanizing agent is not particularly limited, but is preferably 0.1 to 10 parts by weight, more preferably 0.2 to 3 parts by weight with respect to 100 parts by weight of the synthetic isoprene polymer.
- the amount of the vulcanizing agent is within the above range, the phenomenon that the tensile strength of the dip-molded product is reduced because the amount of the vulcanizing agent is excessively small or excessively large can be suppressed. it can.
- vulcanization accelerator As the vulcanization accelerator, those usually used in dip molding can be used. For example, diethyldithiocarbamic acid, dibutyldithiocarbamic acid, di-2-ethylhexyldithiocarbamic acid, dicyclohexyldithiocarbamic acid, diphenyldithiocarbamic acid, dibenzyldithiocarbamic acid, etc.
- These vulcanization accelerators may be used alone or in combination of two or more.
- the amount of the vulcanization accelerator used is 1.2 parts by weight or more, preferably 1.3 parts by weight or more, preferably 1.5 parts by weight or less with respect to 100 parts by weight of the synthetic isoprene polymer. .
- the amount of the vulcanization accelerator used is in the above range, the phenomenon that the tensile strength of the dip-molded product is reduced due to the excessive use of the vulcanization accelerator can be suppressed. Since the amount of the accelerator used is excessively large, it is possible to suppress the phenomenon that the elongation and tensile strength of the dip-molded product are reduced.
- the dip molding composition of the present invention may further contain zinc oxide as necessary.
- the content of zinc oxide is not particularly limited, but is preferably 0.1 to 5 parts by weight, more preferably 0.2 to 2 parts by weight with respect to 100 parts by weight of the synthetic isoprene polymer.
- the zinc oxide content is in the above range, the phenomenon that the tensile strength of the dip-molded product is lowered due to the excessively small zinc oxide content can be suppressed, and the zinc oxide content is low. Since the amount is excessively large, it is possible to suppress the phenomenon that the stability of the synthetic isoprene polymer particles in the dip molding composition is reduced and coarse aggregates are generated.
- the dip molding composition of the present invention may contain a dispersant as necessary.
- the dispersant include fatty acids such as lauric acid, myristic acid, palmitic acid, oleic acid, linolenic acid, and rosin acid.
- anionic surfactants such as alkyl alcohol sulfonates such as sodium dodecylbenzene sulfonate, higher alcohol sulfates and alkyl sulfosuccinates, sodium dodecyl benzene sulfonate is particularly preferable.
- these surfactants may be used individually by 1 type, and may use 2 or more types together.
- the amount of the dispersant used is preferably 0.01 to 5 parts by weight, more preferably 0.05 to 3 parts by weight with respect to 100 parts by weight of the synthetic isoprene polymer.
- the amount of the dispersant used is in the above range, so that the blending stability of the dip molding composition is reduced, or the aggregate is increased during pre-vulcanization.
- the amount of the dispersant used is excessively large, it is possible to suppress the phenomenon that the dip-forming composition is easily foamed and pinholes are easily generated.
- the dip molding composition further includes an anti-aging agent; a reinforcing agent such as carbon black, silica and talc; a filler such as calcium carbonate and clay; an ultraviolet absorber; a plasticizer; Can be blended.
- an anti-aging agent such as carbon black, silica and talc
- a filler such as calcium carbonate and clay
- an ultraviolet absorber such as ultraviolet absorber
- a plasticizer such as silicone wax
- Antiaging agents include 2,6-di-4-methylphenol, 2,6-di-t-butylphenol, butylhydroxyanisole, 2,6-di-t-butyl- ⁇ -dimethylamino-p-cresol, Octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, styrenated phenol, 2,2′-methylene-bis (6- ⁇ -methyl-benzyl-p-cresol), 4, Butylation of 4'-methylenebis (2,6-di-tert-butylphenol), 2,2'-methylene-bis (4-methyl-6-tert-butylphenol), alkylated bisphenol, p-cresol and dicyclopentadiene Phenol-based antioxidants containing no sulfur atom such as reaction products; 2,2′-thiobis- (4-methyl-6-t-butylphenol) 4,4′-thiobis- (6-tert-butyl-o-cresol), 2,6-
- Sulfur ester anti-aging agents of: phenyl- ⁇ -naphthylamine, phenyl- ⁇ -naphthylamine, p- (p-toluenesulfonylamido) -diphenylamine, 4,4 ′-( ⁇ , ⁇ -dimethylbenzyl) diphenylamine, N, N -Diphenyl-p-phenylenediamine, N-isopropyl-N'-phenyl- -Amine-based antioxidants such as phenylenediamine and butyraldehyde-aniline condensates; Quinoline-based antioxidants such as 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline; 2,5-di- And hydroquinone anti-aging agents such as (t-amyl) hydroquinone. These anti-aging agents may be used alone or in combination of two or more.
- the amount of the antiaging agent used is preferably 0.05 to 10 parts by weight, more preferably 0.1 to 5 parts by weight with respect to 100 parts by weight of the synthetic isoprene polymer.
- the amount of the anti-aging agent is within the above range, so that the phenomenon that the synthetic isoprene polymer is deteriorated can be suppressed, and the amount of the anti-aging agent is used. Therefore, the phenomenon that the tensile strength of the dip-molded product is lowered can be suppressed.
- the method for preparing the dip molding composition is not particularly limited.
- the preparation method using a dispersing machine such as a ball mill, a kneader, a disper, etc., the latex of the synthetic isoprene polymer is mixed with a vulcanizing agent, a vulcanization accelerator, the above-described dispersing agent, and other components as required.
- the aqueous dispersion is mixed with the synthetic isoprene polymer latex. The method of doing is mentioned.
- the pH of the dip molding composition is preferably 7 or more, more preferably in the range of pH 8-12.
- the solid content concentration of the dip molding composition is, for example, in the range of 15 to 65% by weight.
- composition for dip molding is preferably aged (also referred to as pre-vulcanization) before being subjected to dip molding.
- the pre-curing time is not particularly limited and depends on the pre-curing temperature, but is preferably 1 to 14 days, and more preferably 1 to 7 days. If the pre-curing time is in the above range, it is possible to suppress the phenomenon that the tensile strength of the resulting dip-molded product is reduced because the pre-curing time is excessively short or excessively long. it can.
- pre-vulcanization After pre-vulcanization, it is preferably stored at a temperature of 10 ° C. to 30 ° C. until it is used for dip molding.
- the temperature to be stored is in the above range, it is possible to suppress the phenomenon that the tensile strength of the resulting dip-formed product is reduced by storing at an excessively high temperature.
- the dip-molded body of the present invention can be obtained by dip-molding the dip-molding composition of the present invention.
- Dip molding is a method in which a mold is immersed in a dip molding composition, the composition is deposited on the surface of the mold, the mold is then lifted from the composition, and the composition deposited on the mold surface is dried. is there.
- the mold before dipping in the dip molding composition may be preheated.
- a coagulant can be used as necessary before the mold is immersed in the dip molding composition or after the mold is pulled up from the dip molding composition.
- the method of using the coagulant include a method in which a mold before dipping in a dip molding composition is immersed in a coagulant solution to attach the coagulant to the mold (anode coagulation dipping method), a dip molding composition
- anode coagulation dipping method a method in which a mold before dipping in a dip molding composition is immersed in a coagulant solution to attach the coagulant to the mold
- a dip molding composition This is a method of immersing the mold in which the material is deposited in a coagulant solution.
- the anode coagulation dipping method is preferable in that a dip-formed body with little thickness unevenness can be obtained.
- coagulants include metal halides such as barium chloride, calcium chloride, magnesium chloride, zinc chloride and aluminum chloride; nitrates such as barium nitrate, calcium nitrate and zinc nitrate; acetates such as barium acetate, calcium acetate and zinc acetate Water-soluble polyvalent metal salts such as calcium sulfate, magnesium sulfate, and sulfates such as aluminum sulfate; Of these, calcium salts are preferable, and calcium nitrate is more preferable. These water-soluble polyvalent metal salts can be used alone or in combination of two or more, and are preferably used in the form of an aqueous solution.
- This aqueous solution may further contain a water-soluble organic solvent such as methyl alcohol and ethyl alcohol, and a nonionic surfactant.
- concentration of the coagulant varies depending on the type of the water-soluble polyvalent metal salt, but is preferably 5 to 50% by weight, more preferably 8 to 30% by weight.
- the heating conditions during vulcanization are not particularly limited, but are preferably 60 to 150 ° C., more preferably 100 to 130 ° C., and preferably 10 to 120 minutes.
- the heating method is not particularly limited, and examples thereof include a method of heating with warm air in an oven and a method of heating by irradiating infrared rays.
- the mold may be washed with water or warm water to remove water-soluble impurities (eg, excess surfactant, coagulant) before or after heating the mold on which the dip molding composition is deposited. preferable.
- water-soluble impurities eg, excess surfactant, coagulant
- the dip-formed body after vulcanization is desorbed from the mold.
- the desorption method include a method of peeling from a mold by hand, a method of peeling by water pressure or compressed air pressure. If the dip-molded product being formed has sufficient strength against desorption, it may be desorbed in the middle step and then the subsequent processing may be continued.
- the dip-molded body is a glove
- organic fine particles such as talc and calcium carbonate or starch particles are used as gloves. It may be dispersed on the surface, an elastomer layer containing fine particles may be formed on the surface of the glove, or the surface layer of the glove may be chlorinated.
- the synthetic isoprene polymer latex obtained in Examples and Comparative Examples was dissolved in tetrahydrofuran so that the solid content concentration was 0.1% by weight. This solution was subjected to gel permeation chromatography analysis and calculated as a weight average molecular weight in terms of standard polystyrene of the synthetic isoprene polymer.
- Mode diameter, median diameter The mode diameter and median diameter of the synthetic isoprene polymer latex obtained in the examples and comparative examples were measured using a laser diffraction particle size distribution analyzer (SALD-2200, manufactured by Shimadzu Corporation). The mode diameter and median diameter were read from the displayed particle diameter measurement results.
- Example 1 (Production of synthetic isoprene polymer latex) 1250 parts of the above-mentioned synthetic isoprene polymer in cyclohexane solution (100 parts of synthetic isoprene polymer, 1150 parts of cyclohexane) and sodium rosinate (trade name “Rondis N-18”, manufactured by Arakawa Chemical Co., Ltd.) as a surfactant 1245 parts of a surfactant aqueous solution containing 8% by weight was prepared.
- cyclohexane solution 100 parts of synthetic isoprene polymer, 1150 parts of cyclohexane
- sodium rosinate trade name “Rondis N-18”, manufactured by Arakawa Chemical Co., Ltd.
- the total amount of the above-mentioned synthetic isoprene polymer in cyclohexane solution and the total amount of the above-mentioned surfactant aqueous solution are stirred and mixed in a SUS304 container, followed by homogenizer (trade name “Milder MDN-303V”, Taiheiyo Kiko Co., Ltd.).
- Emulsified dispersion treatment was performed by a product of Co., Ltd. to obtain an emulsified mixed solution.
- the synthetic isoprene polymer latex from which the aggregates have been removed is centrifuged by a closed disk type continuous centrifuge (SGR509 manufactured by Alfa Laval) at a solid content concentration of 56% at a flow rate of 1600 L / hr at 9000 G. separated.
- SGR509 closed disk type continuous centrifuge
- a synthetic isoprene polymer latex was obtained. This was re-concentrated to a solid content concentration of 66%, and the Brookfield viscosity (V 66 ) was measured. As a result, the viscosity was 112 mPa ⁇ s, and the difference between V 66 and V 56 (V 66 ⁇ V 56 ) was 95 mPa ⁇ It was s. The results are shown in Table 1.
- Example 2 As a surfactant, sodium rosinate (trade name “Londis N-18”, manufactured by Arakawa Chemical Co., Ltd.) 1.2% by weight, and sodium dodecylbenzenesulfonate (trade name “Neoperex G-15”, Kao Corporation A synthetic isoprene polymer latex was obtained in the same manner as in Example 1 except that 1245 parts of an aqueous surfactant solution containing 0.08% by weight was used. Using this, the particle diameter and Brookfield viscosity of the latex were measured in the same manner as in Example 1, and the results are shown in Table 1.
- Example 1 As a surfactant, sodium rosinate (trade name “Longis N-18”, manufactured by Arakawa Chemical Co., Ltd.) 0.8% by weight, and sodium dodecylbenzenesulfonate (trade name “Neoperex G-15”, Kao Corporation A synthetic isoprene polymer latex was obtained in the same manner as in Example 1 except that 1245 parts of an aqueous surfactant solution containing 0.6% by weight was used. Using this, the particle diameter and Brookfield viscosity of the latex were measured in the same manner as in Example 1, and the results are shown in Table 1.
- a synthetic isoprene polymer latex for dip molding containing a synthetic isoprene polymer solution-polymerized using n-butyllithium as a polymerization catalyst, the mode diameter and median diameter of the latex particle diameter, When the ratio (mode diameter / median diameter) is 0.8 or more, the Brookfield viscosity (V 56 ) when the solid content concentration is 56% and the Brookfield viscosity (V 66 ) when the solid content concentration is 66%. (V 66 -V 56 ) was 200 mPa ⁇ s or less (Examples 1 and 2).
- the ratio of the obtained latex particle diameter mode diameter to median diameter is 0.8 or more. Even so, when the amount of sodium dodecylbenzenesulfonate used as a surfactant is large, Brookfield viscosity (V 56 ) when the solid concentration is 56% and Brookfield when the solid concentration is 66% The difference (V 66 -V 56 ) from the viscosity (V 66 ) exceeded 200 mPa ⁇ s (Comparative Example 1).
- a synthetic isoprene polymer obtained using a Ziegler-Natta catalyst instead of n-butyllithium as a polymerization catalyst is used, and the ratio of the obtained latex particle diameter to the mode diameter / median diameter (mode diameter / median diameter) is If less than 0.8, the difference (V 66 -V 56 ) between the Brookfield viscosity (V 56 ) when the solid concentration is 56% and the Brookfield viscosity (V 66 ) when the solid concentration is 66% was much higher than 200 mPa ⁇ s (Comparative Example 3).
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Dispersion Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Processes Of Treating Macromolecular Substances (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
- Manufacture Of Macromolecular Shaped Articles (AREA)
Abstract
Description
(1) アルキルリチウム重合触媒を用いて溶液重合された合成イソプレン重合体を含むディップ成形用合成イソプレン重合体ラテックスであって、該ラテックス粒子径のモード径とメディアン径との比(モード径/メディアン径)が、0.8以上であって、固形分濃度が56%時のブルックフィールド粘度(V56)と固形分濃度が66%時のブルックフィールド粘度(V66)との差(V66-V56)が200mPa・s以下であるディップ成形用合成イソプレン重合体ラテックス、
(2) (1)に記載のディップ成形用合成イソプレン重合体ラテックス、硫黄系加硫剤、および加硫促進剤を含有してなるディップ成形用組成物、
(3) (2)に記載のディップ成形用組成物をディップ成形してなるディップ成形体
が提供される。
本発明で用いる合成イソプレン重合体は、イソプレンを重合して得られる。また、本発明で用いる合成イソプレン重合体は、イソプレンと共重合可能な他のエチレン性不飽和単量体を共重合したものであってもよい。合成イソプレン重合体のイソプレン単位の含有量は、柔軟で、引張強さに優れるディップ成形体が得られ易いことから、全単量体単位に対して、好ましくは70重量%以上、より好ましくは90重量%以上、さらに好ましくは95重量%以上、特に好ましくは100重量%(イソプレンの単独重合体)である。
本発明のディップ成形用合成イソプレン重合体ラテックス(以下、単に「合成イソプレン重合体ラテックス」ということがある。)は、上記合成イソプレン重合体を含んでなる。合成イソプレン重合体ラテックスの製造方法としては、イソプレン単位中のシス結合単位の含有率が高い合成イソプレン重合体を用いることができ、引張強さに優れるディップ成形体が得られる観点から、例えば、有機溶媒に溶解または微分散した合成イソプレン重合体の溶液または微細懸濁液を、界面活性剤の存在下に、水中で乳化し、必要により有機溶媒を除去して、合成イソプレン重合体ラテックスを製造する方法が好ましい。
なお、有機溶媒の使用量は、合成イソプレン重合体100重量部に対して、好ましくは2,000重量部以下、より好ましくは20~1,500重量部である。
使用する水の種類としては、硬水、軟水、イオン交換水、蒸留水、ゼオライトウォーターなどが挙げられる。また、メタノールなどのアルコールに代表される極性溶媒を水と併用してもよい。
なお、有機溶媒の除去操作の前後において、凝集物を除去する操作を行ってもよい。
なお、本発明における粘度は、ブルックフィールド粘度計(以下、「B型粘度計」ということがある。)を用いて測定された、液温が25℃での粘度の値である。
これらの界面活性剤の使用量としては、界面活性剤の種類により最適な量は異なるので一概には言えないが、ロジン酸ナトリウム、ロジン酸カリウムの例では、合成イソプレン重合体100重量部に対して、3重量部以下が好ましく、2重量部以下が更に好ましい。
増粘剤の使用量としては、合成イソプレン重合体100重量部に対して、1重量部以下が好ましく、0.1重量部以下が更に好ましい。
なお、電導度は、METTLER TOLEDO社製導電率計(商品名:SG78-FK2)を使用し、測定温度25℃で測定した値である。
本発明のディップ成形用組成物は、上記ディップ成形用合成イソプレン重合体ラテックス、加硫剤、および加硫促進剤を含んでなる。また、必要に応じてその他の成分を含んでいてもよい。
加硫剤としては、例えば、粉末硫黄、硫黄華、沈降硫黄、コロイド硫黄、表面処理硫黄、不溶性硫黄等の硫黄;塩化硫黄、二塩化硫黄、モルホリン・ジスルフィド、アルキルフェノール・ジスルフィド、N,N'-ジチオ-ビス(ヘキサヒドロ-2H-アゼピノン-2)、含りんポリスルフィド、高分子多硫化物、2-(4'-モルホリノジチオ)ベンゾチアゾール等の硫黄系加硫剤等を用いることができる。なかでも、硫黄が好ましく使用できる。これらの加硫剤は、1種を単独で用いてもよいし、2種以上を併用してもよい。
加硫促進剤としては、ディップ成形において通常用いられるものが使用でき、例えば、ジエチルジチオカルバミン酸、ジブチルジチオカルバミン酸、ジ-2-エチルヘキシルジチオカルバミン酸、ジシクロヘキシルジチオカルバミン酸、ジフェニルジチオカルバミン酸、ジベンジルジチオカルバミン酸などのジチオカルバミン酸類およびそれらの亜鉛塩;2-メルカプトベンゾチアゾール、2-メルカプトベンゾチアゾール亜鉛、2-メルカプトチアゾリン、ジベンゾチアジル・ジスルフィド、2-(2,4-ジニトロフェニルチオ)ベンゾチアゾール、2-(N,N-ジエチルチオ・カルバイルチオ)ベンゾチアゾール、2-(2,6-ジメチル-4-モルホリノチオ)ベンゾチアゾール、2-(4′-モルホリノ・ジチオ)ベンゾチアゾール、4-モルホリニル-2-ベンゾチアジル・ジスルフィド、1,3-ビス(2-ベンゾチアジル・メルカプトメチル)ユリアなどが挙げられるが、ジエチルジチオカルバミン酸亜鉛、2-メルカプトベンゾチアゾール、2-メルカプトベンゾチアゾール亜鉛が好ましい。これらの加硫促進剤は、1種を単独で用いてもよいし、2種以上を併用してもよい。
(酸化亜鉛)
本発明のディップ成形用組成物は、さらに酸化亜鉛を必要に応じて含有してもよい。酸化亜鉛の含有量は、特に限定されないが、合成イソプレン重合体100重量部に対して、好ましくは0.1~5重量部、より好ましくは0.2~2重量部である。酸化亜鉛の含有量が上記範囲であると、酸化亜鉛の含有量が過度に少ないためにディップ成形体の引張強さが低下する、という現象を抑えることができ、また、酸化亜鉛の含有量が過度に多いために、ディップ成形用組成物中の合成イソプレン重合体粒子の安定性が低下して粗大な凝集物が発生する、という現象を抑えることができる。
本発明のディップ成形用組成物は、分散剤を必要に応じて含有してもよく、分散剤としては、例えば、ラウリン酸、ミリスチン酸、パルミチン酸、オレイン酸、リノレン酸及びロジン酸などの脂肪酸のナトリウムまたはカリウム塩、ドデシルベンゼンスルホン酸ナトリウムなどのアルキルベンゼンスルホン酸塩、高級アルコール硫酸エステル塩、アルキルスルホコハク酸塩等のアニオン性界面活性剤等が挙げられるが、ドデシルベンゼンスルホン酸ナトリウムが特に好ましい。なお、これらの界面活性剤は、1種を単独で用いてもよいし、2種以上を併用してもよい。
ディップ成形用組成物には、さらに、老化防止剤;カーボンブラック、シリカ、タルク等の補強剤;炭酸カルシウム、クレー等の充填剤;紫外線吸収剤;可塑剤;等の配合剤を必要に応じて配合することができる。
ディップ成形用組成物のpHは7以上であることが好ましく、pH8~12の範囲であることがより好ましい。
また、ディップ成形用組成物の固形分濃度は、例えば、15~65重量%の範囲である。
本発明のディップ成形体は、本発明のディップ成形用組成物をディップ成形することにより得られる。
型をディップ成形用組成物から引き上げた後、例えば、加熱して型上に形成された沈着物を乾燥させる。乾燥条件は適宜選択する。
次いで、加熱して、型上に形成された沈着物を加硫する。
実施例および比較例で得られた合成イソプレン重合体ラテックスを固形分濃度で0.1重量%となるように、テトラヒドロフランに溶解した。この溶液をゲル・パーミエーション・クロマトグラフィー分析し、合成イソプレン重合体の標準ポリスチレン換算の重量平均分子量として算出した。
実施例および比較例で得られた合成イソプレン重合体ラテックスにメタノールを添加し、凝固した。得られた凝固物を乾燥した後、1H-NMR分析して、合成イソプレン重合体中の全イソプレン単位に対するシス結合単位(1,4-シス構造)の含有率を示した。
実施例および比較例で得られた合成イソプレン重合体ラテックスのモード径およびメディアン径は、レーザー回折式粒度分布測定装置(SALD-2200、島津製作所製)を使用して測定した。表示される粒子径測定結果から、モード径とメディアン径を読み取った。
実施例及び比較例において、合成イソプレン重合体ラテックスの粘度は、B型粘度計(ブルックフィールド粘度計、型式BL、東京計器社製)を用いて、液温25℃で測定を行った。
(合成イソプレン重合体の製造)
乾燥され、窒素置換された撹拌付きオートクレーブに、シクロヘキサン1150部とイソプレン100部とテトラメチルエチレンジアミン0.0029部を仕込んだ。オートクレーブ内の温度を60℃にし、撹拌しながら、n-ブチルリチウム15wt%ヘキサン触媒溶液0.0273部を加えて1時間反応させた。重合反応率は99%であった。得られたポリマー溶液に重合停止剤としてメタノール0.0031部を添加し、反応を停止させた。得られた合成イソプレン重合体は、重量平均分子量(Mw)176万、Mw/Mn=1.24、シス結合単位(1,4-シス構造)の含有率は82%であった。
(合成イソプレン重合体ラテックスの製造)
上記の合成イソプレン重合体のシクロヘキサン溶液1250部(合成イソプレン重合体100部、シクロヘキサン1150部)と、界面活性剤としてロジン酸ナトリウム(商品名「ロンヂスN-18」、荒川化学(株)製)0.8重量%を含有してなる界面活性剤水溶液1245部を準備した。
界面活性剤としてロジン酸ナトリウム(商品名「ロンヂスN-18」、荒川化学(株)製)1.2重量%、およびドデシルベンゼンスルホン酸ナトリウム(商品名「ネオペレックスG-15」、花王(株)製)0.08重量%を含有してなる界面活性剤水溶液1245部を用いたこと以外は、実施例1と同様にして合成イソプレン重合体ラテックスを得た。これを用いて実施例1と同様に、ラテックスの粒子径およびブルックフィールド粘度を測定し、結果を表1に示した。
界面活性剤としてロジン酸ナトリウム(商品名「ロンヂスN-18」、荒川化学(株)製)0.8重量%、およびドデシルベンゼンスルホン酸ナトリウム(商品名「ネオペレックスG-15」、花王(株)製)0.6重量%を含有してなる界面活性剤水溶液1245部を用いたこと以外は、実施例1と同様にして合成イソプレン重合体ラテックスを得た。これを用いて実施例1と同様に、ラテックスの粒子径およびブルックフィールド粘度を測定し、結果を表1に示した。
合成イソプレン重合体ラテックスの製造において、用いる合成イソプレン重合体を、チーグラナッタ触媒を用いてイソプレンを溶液重合することにより得られた重量平均分子量が1,300,000の合成イソプレン重合体(商品名「IR2200L」、日本ゼオン(株)製、シス結合単位(1,4-シス構造)の含有率98%)に変更した。更に、界面活性剤としてロジン酸ナトリウム(商品名「ロンヂスN-18」、荒川化学(株)製)0.6重量%、およびドデシルベンゼンスルホン酸ナトリウム(商品名「ネオペレックスG-15」、花王(株)製)0.2重量%を含有してなる界面活性剤水溶液1245部を用いたこと以外は、実施例1と同様にして合成イソプレン重合体ラテックスを得た。これを用いて実施例1と同様に、ラテックスの粒子径およびブルックフィールド粘度を測定し、結果を表1に示した。
界面活性剤としてロジン酸ナトリウム(商品名「ロンヂスN-18」、荒川化学(株)製)0.8重量%、およびドデシルベンゼンスルホン酸ナトリウム(商品名「ネオペレックスG-15」、花王(株)製)0.4重量%を含有してなる界面活性剤水溶液1245部を用いたこと以外は、比較例2と同様にして合成イソプレン重合体ラテックスを得た。これを用いて実施例1と同様に、ラテックスの粒子径およびブルックフィールド粘度を測定し、結果を表1に示した。
次に、実施例1~2および比較例1~3で得られた固形分濃度66%のラテックスを用いて、ダイヤフラム式ポンプ(ウィルデン社)での移送テストを実施した。実施例1および2のラテックスでは全く問題なく全量を移送できたが、比較例1~3においては半量程度の移送時に詰りが発生し、移送できなくなった。ダイヤフラム部を分解して内部を点検したところ、大量の凝集物が生成しており、移送配管を閉塞させていた。
実施例1~2および比較例1~3で得られた固形分濃度66%のラテックスを用いて、ブルックフィールド粘度が60mPa・sになるように各々を蒸留水で希釈した。これらのラテックスに、凝固剤で被覆されたガラス型を、表2に示す時間浸漬してから取り出し、室温で60分間乾燥した後、60℃の温水中に2分間浸漬し、室温で30分間風乾した。次いで、ガラス型表面に形成されたフィルムを剥離し、得られたフィルムの上部、中間部、下部の膜厚を測定した結果を表2に示した。比較例1~3においては、実施例1~2と同程度の膜厚を得るのに長い浸漬時間を要すと共に、膜厚の均一性が悪化する結果となった。
Claims (3)
- アルキルリチウム重合触媒を用いて溶液重合された合成イソプレン重合体を含むディップ成形用合成イソプレン重合体ラテックスであって、
該ラテックス粒子径のモード径とメディアン径との比(モード径/メディアン径)が、0.8以上であって、
固形分濃度が56%時のブルックフィールド粘度(V56)と固形分濃度が66%時のブルックフィールド粘度(V66)との差(V66-V56)が200mPa・s以下である
ディップ成形用合成イソプレン重合体ラテックス。 - 請求項1に記載のディップ成形用合成イソプレン重合体ラテックス、硫黄系加硫剤、および加硫促進剤を含有してなるディップ成形用組成物。
- 請求項2に記載のディップ成形用組成物をディップ成形してなるディップ成形体。
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2017503397A JP6729549B2 (ja) | 2015-03-03 | 2016-02-15 | ディップ成形用合成イソプレン重合体ラテックスの製造方法、ディップ成形用組成物の製造方法およびディップ成形体の製造方法 |
US15/546,597 US10519258B2 (en) | 2015-03-03 | 2016-02-15 | Dip-forming synthetic isoprene polymer latex, dip-forming composition, and dip-formed article |
BR112017017294-1A BR112017017294B1 (pt) | 2015-03-03 | 2016-02-15 | Látex de polímero de isopreno sintético de formação por imersão, composição de formação por imersão, e, artigo formado por imersão |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2015041011 | 2015-03-03 | ||
JP2015-041011 | 2015-03-03 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2016140043A1 true WO2016140043A1 (ja) | 2016-09-09 |
Family
ID=56849361
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2016/054213 WO2016140043A1 (ja) | 2015-03-03 | 2016-02-15 | ディップ成形用合成イソプレン重合体ラテックス、ディップ成形用組成物およびディップ成形体 |
Country Status (5)
Country | Link |
---|---|
US (1) | US10519258B2 (ja) |
JP (1) | JP6729549B2 (ja) |
BR (1) | BR112017017294B1 (ja) |
TW (1) | TW201634490A (ja) |
WO (1) | WO2016140043A1 (ja) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2018092603A1 (ja) * | 2016-11-15 | 2018-05-24 | 日本ゼオン株式会社 | 合成ポリイソプレンラテックスの製造方法 |
WO2018155113A1 (ja) * | 2017-02-24 | 2018-08-30 | 日本ゼオン株式会社 | 合成ポリイソプレンラテックスの製造方法 |
EP3587462A4 (en) * | 2017-02-24 | 2020-11-25 | Zeon Corporation | MANUFACTURING PROCESS FOR MODIFIED POLYMER LATEX |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS3920430B1 (ja) * | 1960-10-24 | 1964-09-19 | ||
JP2009533501A (ja) * | 2006-12-21 | 2009-09-17 | クレイトン・ポリマーズ・リサーチ・ベー・ベー | 人工ラッテクスの調製方法 |
WO2013099501A1 (ja) * | 2011-12-27 | 2013-07-04 | 日本ゼオン株式会社 | ラテックス、ディップ成形用組成物およびディップ成形体 |
WO2014157034A1 (ja) * | 2013-03-28 | 2014-10-02 | 日本ゼオン株式会社 | 合成イソプレン重合体ラテックスの製造方法 |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5234248B2 (ja) | 2008-01-30 | 2013-07-10 | 日本ゼオン株式会社 | ポリマーエマルジョンの製造方法 |
JP6206482B2 (ja) | 2013-02-22 | 2017-10-04 | 日本ゼオン株式会社 | ディップ成形用ラテックス、ディップ成形用組成物およびディップ成形体 |
-
2016
- 2016-02-15 JP JP2017503397A patent/JP6729549B2/ja active Active
- 2016-02-15 WO PCT/JP2016/054213 patent/WO2016140043A1/ja active Application Filing
- 2016-02-15 US US15/546,597 patent/US10519258B2/en active Active
- 2016-02-15 BR BR112017017294-1A patent/BR112017017294B1/pt active IP Right Grant
- 2016-02-23 TW TW105105211A patent/TW201634490A/zh unknown
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS3920430B1 (ja) * | 1960-10-24 | 1964-09-19 | ||
JP2009533501A (ja) * | 2006-12-21 | 2009-09-17 | クレイトン・ポリマーズ・リサーチ・ベー・ベー | 人工ラッテクスの調製方法 |
WO2013099501A1 (ja) * | 2011-12-27 | 2013-07-04 | 日本ゼオン株式会社 | ラテックス、ディップ成形用組成物およびディップ成形体 |
WO2014157034A1 (ja) * | 2013-03-28 | 2014-10-02 | 日本ゼオン株式会社 | 合成イソプレン重合体ラテックスの製造方法 |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2018092603A1 (ja) * | 2016-11-15 | 2018-05-24 | 日本ゼオン株式会社 | 合成ポリイソプレンラテックスの製造方法 |
JPWO2018092603A1 (ja) * | 2016-11-15 | 2019-10-17 | 日本ゼオン株式会社 | 合成ポリイソプレンラテックスの製造方法 |
EP3543289A4 (en) * | 2016-11-15 | 2020-04-29 | Zeon Corporation | METHOD FOR PRODUCING SYNTHETIC POLYISOPRENE LATEX |
WO2018155113A1 (ja) * | 2017-02-24 | 2018-08-30 | 日本ゼオン株式会社 | 合成ポリイソプレンラテックスの製造方法 |
JPWO2018155113A1 (ja) * | 2017-02-24 | 2019-12-12 | 日本ゼオン株式会社 | 合成ポリイソプレンラテックスの製造方法 |
EP3587462A4 (en) * | 2017-02-24 | 2020-11-25 | Zeon Corporation | MANUFACTURING PROCESS FOR MODIFIED POLYMER LATEX |
Also Published As
Publication number | Publication date |
---|---|
JPWO2016140043A1 (ja) | 2017-12-14 |
BR112017017294A2 (ja) | 2018-04-10 |
BR112017017294B1 (pt) | 2022-01-18 |
TW201634490A (zh) | 2016-10-01 |
JP6729549B2 (ja) | 2020-07-22 |
US20180022841A1 (en) | 2018-01-25 |
US10519258B2 (en) | 2019-12-31 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5999103B2 (ja) | ラテックス、ディップ成形用組成物およびディップ成形体 | |
JP5472286B2 (ja) | ディップ成形用組成物及びディップ成形体 | |
WO2014129547A1 (ja) | ディップ成形用ラテックス、ディップ成形用組成物およびディップ成形体 | |
JP5488137B2 (ja) | ディップ成形用組成物及びディップ成形体 | |
WO2017130889A1 (ja) | ラテックス組成物 | |
JP6358262B2 (ja) | ディップ成形用組成物およびディップ成形体 | |
JP6229853B2 (ja) | 合成イソプレン重合体ラテックスの製造方法 | |
JP6191528B2 (ja) | 合成イソプレン重合体ラテックスの製造方法、合成イソプレン重合体ラテックス、ディップ成形用組成物およびディップ成形体 | |
JP6614159B2 (ja) | ディップ成形用合成ポリイソプレンラテックス、ディップ成形用組成物およびディップ成形体 | |
WO2017135144A1 (ja) | 重合体ラテックスの製造方法 | |
JP6879218B2 (ja) | 重合体ラテックスの製造方法 | |
WO2014181714A1 (ja) | 医療用品成形用ポリイソプレンラテックス、ディップ成形用組成物、医療用品およびその成形方法 | |
WO2016140043A1 (ja) | ディップ成形用合成イソプレン重合体ラテックス、ディップ成形用組成物およびディップ成形体 | |
JP6459564B2 (ja) | ディップ成形用合成イソプレン重合体ラテックス、ディップ成形用組成物およびディップ成形体 | |
JP6572902B2 (ja) | ディップ成形体の製造方法 | |
JP2016150946A (ja) | ディップ成形用合成イソプレン重合体ラテックス、ディップ成形用組成物およびディップ成形体 | |
JP2016141691A (ja) | ディップ成形用組成物およびディップ成形体 | |
JP2016160365A (ja) | 合成イソプレン重合体ラテックスの製造方法、合成イソプレン重合体ラテックス、ディップ成形用組成物、およびディップ成形体 | |
JP2016160366A (ja) | ディップ成形用合成イソプレン重合体ラテックス | |
WO2021171994A1 (ja) | ディップ成形体の製造方法 | |
US20230295385A1 (en) | Film molded body | |
JP2016132761A (ja) | ディップ成形体の製造方法およびディップ成形体 | |
WO2023026782A1 (ja) | ラテックス組成物およびディップ成形体 | |
WO2022172696A1 (ja) | 成形体の製造方法 | |
WO2021166725A1 (ja) | ラテックス組成物の製造方法 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 16758737 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 2017503397 Country of ref document: JP Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 15546597 Country of ref document: US |
|
REG | Reference to national code |
Ref country code: BR Ref legal event code: B01A Ref document number: 112017017294 Country of ref document: BR |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 16758737 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 112017017294 Country of ref document: BR Kind code of ref document: A2 Effective date: 20170811 |