TWI729077B - Blooming/exudation inhibitors, compositions containing them, and elastomer moldings - Google Patents

Abstract

The present invention is a blooming/exudation inhibitor, which is characterized by containing powder composed of amorphous inorganic materials. The above-mentioned amorphous inorganic material is preferably a compound represented by the following general formula (1).

aM ¹ ₂ O. bM ² O. cM ³ ₂ O ₃ . dM ⁴ O ₂ . eP ₂ O ₅ . fH ₂ O (1)

(In the formula, M ¹ is an alkali metal atom, M ² is a divalent metal atom, M ³ is a trivalent metal atom, and M ⁴ is a tetravalent metal atom. Among a, b, c, d and e, At least one is a positive number, the rest is 0 or a positive number, and f is a positive number.)

Description

Blooming/exudation inhibitors, compositions containing them, and elastomer moldings

The present invention relates to a molded product (hereinafter also referred to as "elastomer molded product") obtained by using a raw material composition that also contains rubber, elastomer, etc., and blooming/bleeding suppression that can suppress the bleeding or blooming of the compounding agent Agent.

In the past, the raw material composition used in the formation of elastomer molded products, in addition to rubber and elastomer, is also compounded with various additives depending on the required performance. For example, when rubber is the main ingredient, processing oils, processing aids, anti-aging agents, vulcanization accelerators, etc. are combined, and when elastomer is the main ingredient, antioxidants, light stabilizers, and plasticizers are combined.

In recent years, although the various properties of elastomer molded products have been gradually improved, the phenomenon of additives oozing out over time can be seen. Such blooming/bleeding phenomenon not only causes deterioration of appearance, but also fails to maintain initial physical properties. It also leads to poor adhesion between elastomer molded products, or elastomer molded products and packaging materials. Therefore, in order to suppress these disadvantages, attempts have been made to incorporate new additives into the raw material composition.

In Japanese Patent Laid-Open No. 57-18749, a sulfur-vulcanized high-hardness rubber composition is disclosed, which is composed of ethylene, propylene, and non-conjugated dienes. 100 parts by weight of the rubber base material of propylene rubber, containing 0~150 parts by weight of process oil and sufficient carbon black with a vulcanized rubber hardness of 70 or more, or a filler with carbon black as the main body, and use 0.01~10 parts by weight The rubber composition of disulfate compound as a vulcanization accelerator is characterized by adding 0.1 to 15 parts by weight of non-reactive phenol formaldehyde resin or polyethylene glycol.

In Japanese Patent Application Laid-Open No. 2-41345, a rubber composition with improved blooming phenomenon is disclosed, which is characterized by sulfur-based vulcanizing agent and optionally added ethylene containing vulcanization accelerator. Propylene. The diene terpolymer is the base rubber, each 100 parts by weight of the base rubber compounded with 0.2 to 10.0 parts by weight of a zinc dithiophosphate compound with a specific structure.

In Japanese Patent Application Laid-Open No. 3-119044, a rubber product that inhibits blooming with an anti-aging agent is disclosed. The characteristic is that in the rubber compounding, a porous glass with an anti-aging agent attached to the surface and the pores of the rubber product is disclosed. fiber.

In Japanese Patent Application Laid-Open No. 3-139541, an exudation/blooming preventive agent is disclosed, which is compounded with natural rubber, diene-based synthetic rubber or ethylene. A raw material composition mainly composed of propylene rubber, which is composed of a quaternary ammonium salt compound with a specific structure.

In Japanese Patent Laid-Open No. 2000-265049, a bloom inhibitor is disclosed, which is compounded with a raw material composition mainly composed of natural rubber or synthetic rubber, and which is made of ethylene. Saturated carboxylic acid vinyl ester copolymer saponified alkylene oxide adduct and polyether compound.

In addition, Japanese Patent Laid-Open No. 2003-105202 discloses a weather-resistant resin composition characterized by containing 100 parts by weight of polyolefin resin-containing resin, 0.1-20 parts by weight of layered silicate, and hindered amine Light stabilizer and/or ultraviolet absorber 0.01~5 parts by weight, layered silicate, which makes at least part of the single layers of the layered crystals overlap each other so that the center of the single layer surface is staggered, and the appearance is , The system is dispersed into a flat plate with a thickness of 5-50nm and a length of 500nm or more.

The subject of the present invention is to provide a blooming/extrusion inhibitor that is excellent in the bleeding or blooming suppression effect of a compounding agent, a composition containing the same, and an elastomer molded product from an elastomer molded product.

The inventors of the present invention found that if a raw material composition containing a powder composed of an amorphous inorganic material is used, the resulting elastomer molded article can suppress the occurrence of blooming/exudation related to additives and other additives, and complete this invention.

The present invention is as follows.

1. A blooming/exudation inhibitor, which is a material that can inhibit the exudation or blooming of a compounding agent from an elastomer molded product, and is characterized by containing a powder composed of an amorphous inorganic material.

2. The blooming/exudation inhibitor according to the above item 1, wherein the inorganic material is a compound represented by the following general formula (1).

aM ¹ ₂ O. bM ² O. cM ³ ₂ O ₃ . dM ⁴ O ₂ . eP ₂ O ₅ . fH ₂ O (1)

(In the formula, M ¹ is an alkali metal atom, M ² is a divalent metal atom, M ³ is a trivalent metal atom, and M ⁴ is a tetravalent metal atom. Among a, b, c, d and e, At least one is a positive number, the rest is 0 or a positive number, and f is a positive number.)

3. The blooming/exudation inhibitor as described in the above item 2, wherein the M ² O in the above general formula (1) is ZnO.

4. The blooming/exudation inhibitor as described in item 2 above, wherein M ³ ₂ O ₃ in the above general formula (1) is Al ₂ O ₃ .

5. The blooming/exudation inhibitor according to any one of the above items 1 to 4, wherein the specific surface area of the powder is 30 g/m ² or more.

6. A composition comprising the blooming/exudation inhibitor described in any one of the above items 1 to 5, and a composition with an elastomer or uncrosslinked rubber, wherein the blooming/exudation inhibitor The content is 0.5-10% by mass relative to the entire composition.

7. An elastomer molded product obtained from the composition described in the above item 6.

8. A method for inhibiting the blooming/exudation inhibitor as described in any one of items 1 to 5 above to inhibit the exudation or blooming of the compounding agent from the elastomer molded article.

In the present invention, elastomer molded products are mainly elastomers or uncrosslinked rubbers, and are molded products obtained by using a raw material composition (the composition of the present invention) that may contain resin as necessary. The types of compounding agents are divided into elastomer molded products composed of cross-linked products and elastomer molded products composed of non-cross-linked products.

With the blooming/exudation inhibitor of the present invention, it is possible to provide an elastomer molded product capable of suppressing the occurrence of blooming/exudation phenomenon.

Since the composition of the present invention contains a blooming/exudation inhibitor composed of amorphous inorganic powder, it is suitable for the formation of elastomer moldings in which the occurrence of blooming/exudation phenomena is suppressed. In addition, when the composition is used to produce an elastomer molded product, it does not cause deterioration, decomposition, etc., and does not react with other components, so that an elastomer molded product of a predetermined shape can be efficiently manufactured.

Since the elastomer molded article of the present invention contains blooming/exudation inhibitor composed of amorphous inorganic powder, it is not easy to produce blooming/exudation phenomenon caused by time during use or storage, and has excellent appearance over a long period of time. .

Figure 1 shows an example of obtaining an amorphous inorganic powder of 0.01Al ₂ O ₃ . ZnO. Diagram of the method of the half-value width H of the X-ray diffraction peak of _{0.05H 2 O powder.}

Hereinafter, the present invention will be described in detail.

The blooming/exudation inhibitor of the present invention contains a powder composed of an amorphous inorganic material (hereinafter, also referred to as "amorphous inorganic powder"). The blooming/exudation inhibitor of the present invention may be composed only of amorphous inorganic powder, and as long as it can suppress the occurrence of blooming/exudation, it may also be composed of amorphous inorganic powder or other powders.

In the present invention, the term “amorphous” refers to those with low crystallinity in which no peak is detected in the X-ray diffraction image obtained by powder X-ray diffraction measurement, and even if it is detected, the half-value width of the peak is 0.5 degree or more. _{Figure 1 shows the 0.01Al 2} O ₃ used to find an amorphous inorganic material. ZnO. The schematic diagram of the method of the half-value width H of the characteristic diffraction peak at 31.7 degree in the X-ray diffraction image of the powder composed of 0.05H _{2 O shows that H is about 0.8 degree.}

The above-mentioned amorphous inorganic material is not particularly limited. It is preferably an oxide or an oxide containing at least one metal atom selected from alkali metal atoms, divalent metal atoms, trivalent metal atoms, and tetravalent metal atoms. The complex thereof is preferably a compound represented by the following general formula (1), for example.

aM ¹ ₂ O. bM ² O. cM ³ ₂ O ₃ . dM ⁴ O ₂ . eP ₂ O ₅ . fH ₂ O (1)

(In the formula, M ¹ is an alkali metal atom, M ² is a divalent metal atom, M ³ is a trivalent metal atom, and M ⁴ is a tetravalent metal atom. Among a, b, c, d and e, At least one is a positive number, the rest is 0 or a positive number, and f is a positive number.)

In the above general formula (1), M ¹ is an alkali metal atom, and examples thereof include Li, Na, K, Rb, Cs, and the like. Among these, Na is preferred. M ² is a divalent metal atom, and examples thereof include alkaline earth metal atoms such as Be, Mg, Ca, Ba, Cu, Zn, Fe, Co, Ni, Ru, Pd, Pt, Pb, Cd, and the like. Among them, Mg and Zn are preferred. M ³ is a trivalent metal atom, and examples thereof include Al, Fe, and the like. Among these, Al is preferred. In addition, M ⁴ is a tetravalent metal atom, and examples thereof include Si, Ti, Zr, and the like. Among these, Si is preferred.

^{In addition, M 1} , M ² , M ^3, and M ⁴ constituting the above-mentioned general formula (1) may be only one type or two or more types.

Specific examples of the compound represented by the above general formula (1) are represented by the following formulas (1-1) to (1-16). In the following formula, a, b, c, d, and e are 0 or positive numbers, f is a positive number, b=b ₁ +b ₂ , c=c ₁ +c ₂ , and d=d ₁ +d ₂ .

aM ¹ ₂ O. dSiO ₂ . fH ₂ O (1-1)

aM ¹ ₂ O. bM ² O. dSiO ₂ . fH ₂ O (1-2)

aM ¹ ₂ O. cM ³ ₂ O ₃ . dSiO ₂ . fH ₂ O (1-3)

aM ¹ ₂ O. d ₁ M ⁴ O ₂ . d ₂ SiO ₂ . fH ₂ O (1-4)

aM ¹ ₂ O. bM ² O. eP ₂ O ₅ . fH ₂ O (1-5)

aM ¹ ₂ O. cM ³ ₂ O ₃ . eP ₂ O ₅ . fH ₂ O (1-6)

aM ¹ ₂ O. dM ⁴ O ₂ . eP ₂ O ₅ . fH ₂ O (1-7)

aM ¹ ₂ O. bM ² O. cAl ₂ O ₃ . fH ₂ O (1-8)

aM ¹ ₂ O. c ₁ M ³ ₂ O ₃ . c ₂ Al ₂ O ₃ . fH ₂ O (1-9)

aM ¹ ₂ O. dM ⁴ O ₂ . cAl ₂ O ₃ . fH ₂ O (1-10)

aM ¹ ₂ O. bZnO. fH ₂ O (1-11)

cM ³ ₂ O ₃ . bZnO. fH ₂ O (1-12)

aM ¹ ₂ O. b ₁ M ² O. b ₂ ZnO. fH ₂ O (1-13)

aM ¹ ₂ O. cM ³ ₂ O ₃ . bZnO. fH ₂ O (1-14)

aM ¹ ₂ O. dZrO ₂ . fH ₂ O (1-15)

aM ¹ ₂ O. dTiO ₂ . fH ₂ O (1-16)

In the present invention, the compounds represented by the above general formulas (1-1), (1-2), (1-3), (1-11), (1-12) and (1-13), due to the opposite The effect of inhibiting the occurrence of frost/exudation is particularly excellent, so it is particularly good. Specific examples of compounds are as follows.

0.1Na ₂ O. SiO ₂ . 0.1H ₂ O

Na ₂ O. 0.01MgO. SiO ₂ . 0.1H ₂ O

Na ₂ O. 0.2Al ₂ O ₃ . SiO ₂ . 0.1H ₂ O

0.13Na ₂ O. Al ₂ O ₃ . 8.2SiO ₂ . 0.7H ₂ O

0.1Na ₂ O. ZnO. 0.1H ₂ O

ZnO. 0.27H ₂ O

0.2Na ₂ O. 0.1MgO. ZnO. 0.1H ₂ O

0.007Al ₂ O ₃ . ZnO. 0.02H ₂ O

0.007Al ₂ O ₃ . ZnO. 0.15H ₂ O

The shape and particle size of the above-mentioned amorphous inorganic powder are not particularly limited. The median particle size measured by a laser diffraction particle size distribution machine is preferably about 0.1-20μm. Since the dispersibility and processability of the raw material composition used in the manufacture of elastomer moldings, and the resulting elastomer moldings can indeed suppress blooming/exudation, it is particularly preferred to be 0.5~15μm .

Since the specific surface area of the above-mentioned amorphous inorganic powder can obtain sufficient suppression effect of blooming/exudation appearance of the elastomer molded article, it is preferably 30g/m ² or more, more preferably 50m ² /g or more. More preferably, it is 80 m ² /g or more, particularly ^{preferably 100 to 450 m 2} /g. In addition, the specific surface area of the above-mentioned amorphous inorganic powder can be measured by the BET method.

As mentioned above, the blooming/exudation inhibitor of the present invention may also contain powders (other powders) composed of other inorganic materials or organic materials. However, in this case, the blooming/exudation inhibitor of the present invention contains amorphous The lower limit of the content of the inorganic powder is preferably 50% by mass, more preferably 80% by mass.

The composition of the present invention (hereinafter referred to as "raw material composition") is characterized by containing the blooming/exudation inhibitor of the present invention, and an elastomer or uncrosslinked rubber. The raw material composition of the present invention may further contain resins, additives, solvents and the like. The resin may be any of thermoplastic resin and curable resin. Hereinafter, regardless of whether it may contain a resin, the elastomer or uncrosslinked rubber is collectively referred to as a "polymer component".

For the above-mentioned elastomers and uncrosslinked rubbers, (co)polymers containing structural units derived from diene compounds or their hydrogen additives (hereinafter referred to as "diene elastomers") can be used; olefin copolymers; Acrylic rubber; polyurethane-based elastomer; polyester-based elastomer; polyamide-based elastomer, etc.

The above-mentioned diamine-based elastomer may further contain a structural unit derived from an aromatic vinyl compound, a structural unit derived from a vinyl cyanide compound, and the like.

The above-mentioned diamine-based elastomers include, for example, polybutadiene rubber, polyisoprene rubber, and styrene. Butadiene copolymer rubber (SBR), chloroprene rubber (CR), acrylonitrile. Butadiene rubber (NBR), isoprene. Isobutylene copolymer rubber (IIR), styrene AB diblock copolymer, styrene ABA triblock copolymer, styrene ABAB tetrablock copolymer, styrene ABABA pentablock copolymer Compounds, styrene-based multi-block copolymers with AB repeating units above these.

The above-mentioned olefin copolymer includes, for example, a copolymer containing ethylene, a structural unit derived from α-olefin, and a structural unit derived from a non-conjugated diene compound or its carboxylic acid anhydride modified product (hereinafter referred to as "ethylene .Α-olefin copolymer rubber"); copolymers containing ethylene units and structural units derived from unsaturated carboxylic acids.

The above ethylene. The α-olefin of the α-olefin copolymer rubber includes, for example, propylene, 1-butene, 1-pentene, 1-hexene, etc., and the non-conjugated diene compound includes, for example, dicyclopentadiene, 5 -Ethylene-2-norbornene, 1,4-hexadiene, methyl tetrahydroindene, methyl norbornene, etc.

The above ethylene. α-olefin copolymer rubber, for example ethylene. Propylene copolymer rubber, ethylene. Butene copolymer rubber, ethylene. Hexene copolymer rubber, ethylene. Octene copolymer rubber, etc.

When the above-mentioned polymer component contains a resin, the resin is usually selected depending on the type of elastomer or uncrosslinked rubber. Examples of the above-mentioned resins include olefin resins, acrylic resins, and resins containing structural units derived from aromatic vinyl compounds.

In the production of the raw material composition of the present invention, since it is possible to efficiently produce a uniform composition of the elastomeric body, the moisture content of the blooming/exudation inhibitor used is preferably 1-15% by mass, more preferably It is 1-10% by mass. The above-mentioned moisture content can be determined by the Carl-Fisher method.

The content of the blooming/exudation inhibitor in the raw material composition of the present invention is 0.5-10% by mass, and more preferably, because it has sufficient inhibitory effect on the blooming/exudation phenomenon of the elastomer molded article. It is 1-8% by mass, and more preferably 2-6% by mass. If the content exceeds 10 parts by mass, it may cause disadvantages such as a decrease in the strength of the elastomer molded product and a change in color tone. In the present invention, only one type of blooming/exudation inhibitor may be used, or two or more types may be used in combination.

The raw material composition of the present invention usually contains compounding agents such as additives and solvents in order to improve processability and efficiently produce elastomer molded articles having desired shapes or characteristics.

Additives include, for example, antioxidants, ultraviolet absorbers, light stabilizers, anti-aging agents, plasticizers, flame retardants, antistatic agents, antifungal agents, colorants, crosslinking agents (vulcanizing agents), vulcanization accelerators, Vulcanization retarders, degelling agents, processing aids such as stearic acid, lubricants such as waxes, process oils, thickeners, fillers, methylene donors, methylene acceptor organic cobalt compounds, etc. Among these, the ingredients related to blooming/exudation phenomena are antioxidants, ultraviolet absorbers, light stabilizers, anti-aging agents, plasticizers, flame retardants, antistatic agents, antifungal agents, vulcanization accelerators, Processing aids, lubricants, operating oils, etc.

Examples of the antioxidants include hindered amine compounds, hydroquinone compounds, hindered phenol compounds, sulfur-containing compounds, and phosphorus-containing compounds.

Examples of the ultraviolet absorber include benzophenone-based compounds, benzotriazole-based compounds, and triazine-based compounds.

Examples of the above-mentioned light stabilizers include hindered amine compounds.

The aforementioned anti-aging agents include, for example, naphthylamine-based compounds, diphenylamine-based compounds, p-phenylenediamine-based compounds, quinoline-based compounds, hydroquinone derivative-based compounds, monophenol-based compounds, bisphenol-based compounds, Triphenol-based compounds, polyphenol-based compounds, thiobisphenol-based compounds, hindered phenol-based compounds, phosphite-based compounds, imidazole-based compounds, nickel dithiocarbamate-based compounds, phosphoric acid-based compounds, and the like.

The above-mentioned plasticizers include, for example, phthalic acid esters, trimellitates, pyromellitic acid esters, aliphatic monobasic acid esters, aliphatic dibasic acid esters, phosphoric acid esters, polyol esters, and epoxy-based plasticizers Agent, polymer plasticizer, chlorinated paraffin, etc.

Examples of the above-mentioned flame retardants include halogen-containing compounds, phosphorus-containing compounds, and silicone-based compounds.

啉硫代)苯并噻唑、二苯并噻唑-二硫化二苯并噻唑等噻唑系化合物；二苯胍、三苯胍、二鄰甲苯胍、鄰甲苯雙胍、二苯胍苯甲酸酯等胍系化合物；二苯硫脲、二乙硫脲、二丁硫脲、三甲硫脲、二鄰甲苯硫脲等硫脲系化合物；乙醛-苯胺縮合物、六甲甲基四胺、乙醛氨等醛胺或醛-氨系化合物；2-巰基咪唑啉等咪唑啉系化合物；黃原酸鋅等黃原酸鹽系化合物；鋅白等。 The above-mentioned vulcanization accelerators include, for example, zinc dimethyldithiocarbamate, zinc diethylenedithiocarbamate, zinc di-n-butanedithiocarbamate, zinc ethylphenyldithiocarbamate, and butylphenyl disulfide. Dithiocarbamic acid compounds such as zinc carbamate, sodium dimethyldithiacarbamate, selenium dimethyldithiacarbamate, and antimony diethylenedithiacarbamate; tetramethylthiuram monosulfide, tetramethylthiuram disulfide Thiuram, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, dipentylthiuram tetrasulfide and other thiuram compounds; N-cyclohexyl-2-benzothiazole sulfenamide , N-oxydiethylene-2-benzothiazolesulfenamide, N,N-diisopropyl-2-benzothiazolesulfenamide, 2-mercaptobenzothiazole, 2-(2,4- Dinitrophenyl) mercaptobenzothiazole, 2-(2,6-diethyl-4-

(Pholinothio) benzothiazole, dibenzothiazole-dibenzothiazole disulfide and other thiazole compounds; diphenylguanidine, triphenylguanidine, di-o-toluene guanidine, o-toluene biguanide, diphenylguanidine benzoate and other guanidines Series compounds; diphenylthiourea, diethylthiourea, dibutylthiourea, trimethylthiourea, di-o-toluenethiourea and other thiourea compounds; acetaldehyde-aniline condensate, hexamethylmethyltetramine, acetaldehyde ammonia, etc. Aldehyde or aldehyde-ammonia compounds; imidazoline compounds such as 2-mercaptoimidazoline; xanthate compounds such as zinc xanthate; zinc white, etc.

Examples of the above-mentioned process oils include naphthylamine-based oils and paraffin-based oils.

Examples of the above-mentioned filler include inorganic fillers such as silica, talc, calcium carbonate, and carbon black; and polymer fillers such as coumarone-indene resin, high styrene resin, and phenol resin.

When manufacturing elastomer molded articles with a crosslinked structure, crosslinking agents (vulcanizing agents) such as sulfur compounds and organic peroxides are used.

啉、二硫烷基酚、二硫化四甲基秋蘭姆、二硫胺甲酸硒等。 The above-mentioned sulfur compounds include, for example, sulfur, sulfur chloride, sulfur dichloride, and disulfide

Phosphine, disulfide alkylphenol, tetramethylthiuram disulfide, selenium dithiocarbamate, etc.

The above-mentioned organic peroxides include, for example, dicumyl peroxide, 2,5-dimethyl-2,5-bis(tertiarybutylperoxy)hexane, 2,5-dimethyl-2, 5-bis(benzyl peroxide) hexane, 2,5-dimethyl-2,5-bis(tertiary butyl peroxide) hexyne, di-tertiary butyl peroxide, two peroxide -Tertiary butyl-3,3,5-trimethylcyclohexane, tertiary butanol peroxide, etc.

In addition, when an organic peroxide is used as a crosslinking agent, it is preferable to use a crosslinking auxiliary agent in combination. Examples of crosslinking aids include sulfur; benzoquinone dioxime-based compounds such as p-benzoquinone dioxime; methacrylate-based compounds such as polyethylene glycol dimethacrylate; diallyl phthalate , Triallyl isocyanate and other allyl compounds; maleic amine compounds such as bismaleamide; divinylbenzene, etc.

In addition, when a sulfur-based compound is used as the vulcanizing agent, it is preferable to use the above-mentioned vulcanization accelerator in combination.

For the raw material composition of the present invention, for example, the raw material components can be kneaded with a closed kneader, open roll, extruder, etc., and then the resulting kneaded product may be mixed with a crosslinking agent (vulcanizing agent), Vulcanization accelerator, etc. are manufactured. Here, the method of using the raw materials includes the method of using the total amount at a time, and the method of mixing the blooming/exudation inhibitor and the compounding agent in advance, and then kneading the resulting mixture with elastomer or uncrosslinked rubber .

The elastomer molded article of the present invention is an article obtained by using the above-mentioned raw material composition of the present invention. Specific manufacturing methods include, for example, injection molding, extrusion molding, inflation molding, vacuum molding, foam molding, and hot pressing. Thereby, the elastomer molded article of the present invention can be made of a solid body or a foamed body, and in the solid part, it has the following structure: in a cross-linked polymer matrix or a non-cross-linked polymer matrix , Dispersely contain blooming/exudation inhibitors, and ingredients related to blooming/exudation phenomenon contained in the raw material composition as a compounding agent.

Although the reason why the formed elastomer product containing the blooming/exudation inhibitor of the present invention can effectively suppress the occurrence of blooming/exudation phenomenon is not clear, the inventors speculate that it is due to the effect of the blooming/exudation inhibitor and additives. Because of the high affinity.

[Example]

Hereinafter, examples are given to explain the present invention more specifically, but the present invention is not limited to these examples. Also, "%" refers to mass %.

1. Evaluation method

(1) Powder X-ray diffraction of blooming/exudation inhibitor

The X-ray diffraction device "RINT2400V" (model name) manufactured by Rigaku Corporation was used to measure powder X-ray diffraction with Cu Kα rays to obtain an X-ray diffraction image. The measurement conditions are a tube voltage of 40kV and a current of 150mA. Use the method shown in Figure 1 to obtain the half-value width of the diffraction peak at a specific position (2θ).

(2) Specific surface area of blooming/exudation inhibitor

According to JIS Z8830-2001, "Method for Measuring the Specific Surface Area of Powder (Solid) by Gas Adsorption", the measurement was carried out using a continuous flow surface area meter "SA-6200" (model name) manufactured by Horiba Manufacturing Co., Ltd.

(3) The median diameter of blooming/exudation inhibitor (d50)

The blooming/exudation inhibitor was measured using a laser diffraction particle size distribution analyzer "MS2000" (model name) manufactured by Malvern, and the median particle size (d50) was measured on a volume basis.

(4) Confirmation test of suppression effect of blooming/exudation phenomenon

70 parts by mass of the hydrogen additive of the styrene-based tetrablock copolymer, 30 parts by mass of the hydrogen additive of the styrene-based triblock copolymer, and 20 parts by mass of the polypropylene resin relative to the polymer components A total of 3% by mass or 6% by mass of blooming/exudation inhibitor and 0.5 parts by mass of carbon black were dry-mixed using a Henschel mixer. Next, 100 parts by mass of naphthenic oil was added and mixed thoroughly to obtain a raw material composition. After that, it was melt-kneaded at about 200°C using an extruder to produce raw material pellets. Next, an injection molding machine was used to prepare a plate-shaped test piece (11 mm×11 mm×1 mm) at 170°C. Then store at 50°C for two weeks. The surface of the plate-shaped test piece before and after the catheter was visually observed, and the evaluation was performed based on the following criteria.

○: No bleeding or rainbow color development is seen

×: Bleeding or rainbow color development is remarkable

2. Preparation of a composition containing blooming/exudation inhibitors, production and evaluation of test pieces (elastomer molded products) Examples 1 and 2

As a blooming/exudation inhibitor, the half-value width of the diffraction peak of 31.7deg. of X-ray diffraction image is about 0.8deg. of 0.007Al ₂ O ₃ . ZnO. 0.15H ₂ O powder (specific surface area: ^{104 m 2} /g, median particle size: 1.7 μm) is prepared into a raw material composition containing 3% by mass or 6% by mass relative to the total polymer components. After that, a confirmation test of the inhibitory effect of blooming/exudation phenomenon was carried out (refer to Table 1).

Example 3

As a blooming/exudation inhibitor, it is used in X-ray diffraction images for ZnO where no clear diffraction peak is detected. 0.27H ₂ O powder (specific surface area: 188 m ² /g, median particle size: 9.8 μm) was prepared into a raw material composition containing 3% by mass relative to the total polymer components. After that, a confirmation test of the inhibitory effect of blooming/exudation phenomenon was carried out (refer to Table 1).

Example 4

_{As a blooming/exudation inhibitor, 0.13Na 2} O was used in X-ray diffraction images where no clear diffraction peak was detected. Al ₂ O ₃ . 8.2SiO ₂ . 0.7H ₂ O powder (specific surface area: 245 m ² /g, median particle size: 7.9 μm) was prepared into a raw material composition containing 3% by mass of the total polymer components. After that, a confirmation test of the inhibitory effect of blooming/exudation phenomenon was carried out (refer to Table 1).

Comparative example 1

As a blooming/exudation inhibitor, a powder composed of zinc oxide (hereinafter referred to as "zinc oxide (I)") (hereinafter referred to as "zinc oxide (I)") whose half-value width of the diffraction peak of 31.7 deg. of X-ray diffraction image is 0.1 deg. Specific surface area: 0.4 m ² /g, median particle size: 0.3 μm), prepared into a raw material composition containing 3% by mass relative to the total polymer components. After that, a confirmation test of the inhibitory effect of blooming/exudation phenomenon was carried out (refer to Table 1).

Comparative example 2

As a blooming/exudation inhibitor, a powder composed of zinc oxide (hereinafter referred to as "zinc oxide (II)") whose half-value width of the diffraction peak of 31.7 deg. of X-ray diffraction image is 0.3 deg. (hereinafter referred to as "zinc oxide (II)") is used. Specific surface area: 20 m ² /g, median particle size: 0.2 μm), prepared into a raw material composition containing 3% by mass relative to the total polymer components. After that, a confirmation test of the inhibitory effect of blooming/exudation phenomenon was carried out (refer to Table 1).

Comparative example 3

^{As a blooming/exudation inhibitor, talc powder (specific surface area: 22m 2} /g, median particle size: 7.8μm) with the half-value width of the diffraction peak of 9.4deg. of X-ray diffraction image of 0.2deg. is used, Prepare a raw material composition containing 3% by mass relative to the total polymer components. After that, a confirmation test of the inhibitory effect of blooming/exudation phenomenon was carried out (refer to Table 1).

Comparative example 4

Using only the elastomer not compounded with the blooming/exudation inhibitor, a plate-shaped test piece was prepared, and a confirmation test of the inhibitory effect of blooming/exudation phenomenon was performed (see Table 1).

It can be understood from Table 1 that the blooming/exudation inhibitors used in Examples 1 to 4 can provide elastomer moldings that have the effect of inhibiting blooming/exudation appearance for a long time.

[Industrial Utilization]

By using the blooming/exudation inhibitor of the present invention or a composition containing the same, it is possible to suppress the appearance of various elastomer molded products such as poor appearance, so that the decrease in physical properties can be reduced. Therefore, the blooming/exudation inhibitor of the present invention or the composition containing the same is suitable for the formation of various components such as long-term use in the automobile field, OA home appliance field, electrical and electronic field, medical field, tools, and daily sundries. Specific elastomer molded products include, for example, gaskets, covers, tubes, silencer gears, tool fixtures, toothbrushes, pens, razors, knives, etc., grips, shoe soles, handbrake grips, shift knobs, Elbow rests, armrests, toys, etc.

Claims (5)

A blooming/exudation inhibitor, which is a material that can inhibit the exudation or blooming of a compounding agent from an elastomer molded product, and is characterized by containing a powder composed of an amorphous inorganic material. The above-mentioned amorphous inorganic material is The compound represented by the following general formula (1) has no peak detected in the X-ray diffraction image obtained by powder X-ray diffraction measurement, or even if detected, it is a low crystal with a peak half-value width of 0.5 degree or more The quality, aNa ₂ O. bZnO. cAl ₂ O ₃ . dSiO ₂ . eP ₂ O ₅ . fH ₂ O (1) (where a, b, c, d, and e are 0 or a positive number, at least one of b and c is an integer, and f is a positive number). Such as the blooming/exudation inhibitor of claim 1, wherein the specific surface area of the above-mentioned powder is 30 g/m ² or more. A composition containing the blooming/exudation inhibitor as described in claim 1 and an elastomer or uncrosslinked rubber composition, wherein the content of the blooming/exudation inhibitor is relative to the above composition The whole is 0.5-10% by mass. An elastomer molded product obtained from the composition described in claim 3. A method for inhibiting the blooming/exudation inhibitor as described in Claim 1 to inhibit the exudation or blooming of the compounding agent from the elastomer molded article.

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