JP2013173829A - Solid natural rubber, natural rubber composition using the same, and crosslinked material - Google Patents
Solid natural rubber, natural rubber composition using the same, and crosslinked material Download PDFInfo
- Publication number
- JP2013173829A JP2013173829A JP2012038436A JP2012038436A JP2013173829A JP 2013173829 A JP2013173829 A JP 2013173829A JP 2012038436 A JP2012038436 A JP 2012038436A JP 2012038436 A JP2012038436 A JP 2012038436A JP 2013173829 A JP2013173829 A JP 2013173829A
- Authority
- JP
- Japan
- Prior art keywords
- natural rubber
- composition
- solid
- crosslinking
- crosslinked
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L7/00—Compositions of natural rubber
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08C—TREATMENT OR CHEMICAL MODIFICATION OF RUBBERS
- C08C1/00—Treatment of rubber latex
- C08C1/02—Chemical or physical treatment of rubber latex before or during concentration
- C08C1/04—Purifying; Deproteinising
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L15/00—Compositions of rubber derivatives
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Processes Of Treating Macromolecular Substances (AREA)
- Manufacture Of Macromolecular Shaped Articles (AREA)
Abstract
Description
本発明は、ゴム製品の製造原料となる固形天然ゴムに関する。 The present invention relates to a solid natural rubber that is a raw material for producing rubber products.
天然ゴムは、引張り強さが大きく、振動による発熱が少ない等の優れた性質を有している。このため、従来より、タイヤ、防振ゴム、ベルト、ゴム手袋等、様々なゴム製品の原料として用いられている。ゴム製品の製造原料として流通している固形の天然ゴムは、視覚格付けゴム（ＶＧＲ）と、技術的格付けゴム（ＴＳＲ）と、に大別される。ＶＧＲの中では、「天然ゴム各種等級品の国際品質包装規格（通称グリーンブック）」に基づく格付けによる燻煙シート（ＲＳＳ）が代表的である。例えば、ＲＳＳは、次のようにして製造される。まず、フィールドラテックスにギ酸や酢酸等の酸を加えて凝固させた後、作業台の上に載せ、棒で伸ばして厚さを調整する。続いて、波形（リブ形状）ロールで伸ばしながら水分を絞り、シート状に成形する。次に、成形したシートを数日間吊して乾燥させる。そして、乾燥後の未燻煙シート（ＵＳＳ）を水洗し、数日間燻煙、乾燥させる。また、ＴＳＲは、カップランプ（フィールドラテックスが収集カップ中で自然凝固したもの）等の原料を粉砕しながら水洗し、粉砕物を繰り返しロールに通して水分を絞り出した後、熱風乾燥させて製造される。 Natural rubber has excellent properties such as high tensile strength and low heat generation due to vibration. For this reason, it has been conventionally used as a raw material for various rubber products such as tires, anti-vibration rubber, belts and rubber gloves. Solid natural rubber distributed as a raw material for producing rubber products is roughly classified into visual rating rubber (VGR) and technical rating rubber (TSR). A representative example of VGR is a smoke sheet (RSS) based on a rating based on “International Quality Packaging Standard for Natural Rubber Grades (commonly called Green Book)”. For example, RSS is manufactured as follows. First, after adding acid such as formic acid or acetic acid to the field latex and coagulating it, it is placed on a work table and stretched with a stick to adjust the thickness. Subsequently, the water is squeezed while being stretched by a corrugated (rib-shaped) roll, and formed into a sheet shape. Next, the molded sheet is hung for several days and dried. Then, the dried smokeless sheet (USS) is washed with water, smoked and dried for several days. TSR is manufactured by rinsing raw materials such as cup lamps (field latex naturally solidified in a collection cup) while pulverizing, repeatedly passing the pulverized product through a roll and squeezing out moisture, and then drying with hot air. The
上述したように、固形の天然ゴムを製造する場合には、ラテックスの酸による凝固、水分を絞りながらのシート成形、およびシートの水洗といった工程が必要である。一方、天然ゴムには、ゴム成分の他に、タンパク質、脂質等の非ゴム成分が含まれる。これらの非ゴム成分のうち、タンパク質等の水溶性のものは、ロールで伸ばしてシート化する際や、水洗の際に、水分と共に流出する。このため、水溶性の非ゴム成分を含む排水の処理が、問題になる。また、本発明者が検討した結果、タンパク質の流出は、天然ゴムが本来有する機能を低下させ、それから製造されるゴム製品の特性にも影響を及ぼす、という知見が得られた。 As described above, in the case of producing solid natural rubber, processes such as coagulation of latex with acid, sheet molding while squeezing moisture, and washing of the sheet with water are necessary. On the other hand, natural rubber includes non-rubber components such as proteins and lipids in addition to rubber components. Among these non-rubber components, water-soluble ones such as proteins flow out together with moisture when stretched with a roll to form a sheet or when washed with water. For this reason, the process of the waste_water | drain containing a water-soluble non-rubber component becomes a problem. Further, as a result of investigation by the present inventor, it has been found that protein outflow lowers the natural function of natural rubber and affects the properties of rubber products produced therefrom.
本発明は、このような実情に鑑みてなされたものであり、天然ゴムに元々含まれるタンパク質の残存量が多い固形天然ゴム、およびそれを含む天然ゴム組成物を提供することを課題とする。また、架橋密度および強度が大きい天然ゴムの架橋物を提供することを課題とする。 This invention is made | formed in view of such a situation, and makes it a subject to provide the solid natural rubber with many residual amounts of the protein originally contained in natural rubber, and a natural rubber composition containing the same. It is another object of the present invention to provide a crosslinked product of natural rubber having a high crosslinking density and strength.
（１）本発明の固形天然ゴムは、天然ゴムラテックスを乾燥して製造され、窒素含有量が０．６質量％以上であることを特徴とする。本明細書においては、窒素含有量として、Ｐｅｒｋｉｎ Ｅｌｍｅｒ社の「２４００ＩＩ 全自動元素分析装置（ＣＨＮＳ／Ｏ）」により測定された値を採用している。 (1) The solid natural rubber of the present invention is produced by drying natural rubber latex and has a nitrogen content of 0.6% by mass or more. In this specification, the value measured by "2400II fully automatic elemental analyzer (CHNS / O)" of Perkin Elmer is adopted as nitrogen content.
上述したように、天然ゴムには、元々、タンパク質、脂質等の非ゴム成分が含まれる。架橋前の固形天然ゴム中の窒素は、主にタンパク質に由来する。このため、窒素含有量が多いほど、タンパク質が多く含まれると考えられる。本発明の固形天然ゴムにおいては、窒素含有量が多い。換言すると、残存たんぱく質量が多い。このため、本発明の固形天然ゴムによると、天然ゴムが本来有する機能を、充分発揮させることができる。 As described above, natural rubber originally contains non-rubber components such as proteins and lipids. Nitrogen in the solid natural rubber before crosslinking is mainly derived from proteins. For this reason, it is thought that more protein is contained, so that there is much nitrogen content. The solid natural rubber of the present invention has a high nitrogen content. In other words, the residual protein mass is high. For this reason, according to the solid natural rubber of this invention, the function which natural rubber originally has can be fully exhibited.
具体的には、本発明の固形天然ゴムを硫黄架橋した場合、架橋速度および架橋密度が大きくなる。この理由としては、次の二つが考えられる。一つは、タンパク質が加硫促進剤となり、ゴム成分と硫黄との反応を促進するからである。もう一つは、タンパク質自身が、架橋剤としての役割を果たし、タンパク質を介した新たな架橋構造が形成されるからである。また、本発明の固形天然ゴムを架橋して得られる架橋物の強度が、大きくなる。これは、タンパク質が天然ゴムの補強材として機能しているため、と考えられる。特に、本発明の固形天然ゴムに、補強材としてカーボンブラックを配合した場合には、タンパク質が、あたかもカップリング剤のように天然ゴムとカーボンブラックとの間を橋渡しして、両者の結合を促進すると考えられる。 Specifically, when the solid natural rubber of the present invention is sulfur cross-linked, the cross-linking speed and cross-linking density are increased. There are two possible reasons for this. One is that protein serves as a vulcanization accelerator and promotes the reaction between the rubber component and sulfur. The other is that the protein itself serves as a cross-linking agent and a new cross-linked structure is formed via the protein. In addition, the strength of the crosslinked product obtained by crosslinking the solid natural rubber of the present invention is increased. This is considered because protein functions as a reinforcing material for natural rubber. In particular, when carbon black is compounded as a reinforcing material in the solid natural rubber of the present invention, the protein bridges between natural rubber and carbon black as if it were a coupling agent and promotes the binding between the two. I think that.
このように、本発明の固形天然ゴムを用いると、水洗等によりタンパク質が流出した従来の固形天然ゴムと比較して、架橋物（ゴム製品）を製造する際の架橋時間を短縮することができる。すなわち、架橋に必要な加熱時間を、短縮することができる。これにより、架橋物の製造工程におけるエネルギー消費を低減し、製造コストを削減することができる。また、架橋密度および強度が大きい架橋物を製造することができる。 As described above, when the solid natural rubber of the present invention is used, the cross-linking time for producing a cross-linked product (rubber product) can be shortened as compared with the conventional solid natural rubber from which protein has flowed out by washing or the like. . That is, the heating time required for crosslinking can be shortened. Thereby, the energy consumption in the manufacturing process of a crosslinked product can be reduced, and manufacturing cost can be reduced. In addition, a crosslinked product having a high crosslinking density and strength can be produced.
（２）本発明の天然ゴム組成物は、上記（１）構成の固形天然ゴムを含む。本発明の天然ゴム組成物は、本発明の固形天然ゴムの他、架橋剤、加硫促進剤、酸化亜鉛、加工助剤、補強材、老化防止剤、軟化剤等を含んで構成すればよい。 (2) The natural rubber composition of the present invention includes the solid natural rubber having the structure (1). The natural rubber composition of the present invention may comprise a solid natural rubber of the present invention, a crosslinking agent, a vulcanization accelerator, zinc oxide, a processing aid, a reinforcing material, an antiaging agent, a softening agent, and the like. .
本発明の天然ゴム組成物によると、架橋物（ゴム製品）を製造する際の架橋時間を短縮することができる。これにより、架橋物の製造工程におけるエネルギー消費を低減し、製造コストを削減することができる。また、架橋密度および強度が大きい架橋物を製造することができる。 According to the natural rubber composition of the present invention, the crosslinking time when producing a crosslinked product (rubber product) can be shortened. Thereby, the energy consumption in the manufacturing process of a crosslinked product can be reduced, and manufacturing cost can be reduced. In addition, a crosslinked product having a high crosslinking density and strength can be produced.
（３）本発明の架橋物は、上記（２）の構成の天然ゴム組成物を架橋してなる。上記（１）、（２）において説明した通り、本発明の架橋物においては、架橋密度および強度が大きい。 (3) The crosslinked product of the present invention is obtained by crosslinking the natural rubber composition having the constitution (2). As explained in the above (1) and (2), the crosslinked product of the present invention has a high crosslinking density and strength.
以下、本発明の固形天然ゴム、天然ゴム組成物、および架橋物の実施形態について説明する。 Hereinafter, embodiments of the solid natural rubber, the natural rubber composition, and the crosslinked product of the present invention will be described.
＜固形天然ゴム＞
天然ゴムラテックスを酸により凝固して、水分を絞りながらのシート成形、およびシートの水洗を行う従来の方法によると、天然ゴムに含まれるタンパク質が、水分と共に流出する。このため、従来の方法により得られる固形天然ゴムの窒素含有量は、０．５質量％程度である。これに対して、本発明の固形天然ゴムの窒素含有量は、０．６質量％以上である。窒素含有量が０．７質量％以上であると、より好適である。
<Solid natural rubber>
According to a conventional method in which natural rubber latex is coagulated with an acid, and sheet forming while squeezing moisture and washing the sheet with water are performed, proteins contained in natural rubber flow out together with moisture. For this reason, the nitrogen content of the solid natural rubber obtained by the conventional method is about 0.5% by mass. On the other hand, the nitrogen content of the solid natural rubber of the present invention is 0.6% by mass or more. It is more preferable that the nitrogen content is 0.7% by mass or more.
本発明の固形天然ゴムは、天然ゴムラテックスを乾燥して製造される。天然ゴムラテックスとしては、タッピングにより採液されたフィールドラテックスや、それにアンモニアを加えて処理されたラテックス（ハイアンモニアラテックス）を用いればよい。すなわち、本発明の固形天然ゴムは、従来の方法とは異なり、天然ゴムラテックスの凝固、凝固物の水分絞り出しおよび水洗を行わずに、製造される。凝固物の水分の絞り出しや水洗を行わないため、水溶性の非ゴム成分であるタンパク質の流出が抑制される。つまり、天然ゴムに元々含まれるタンパク質を、残存させることができる。この場合、従来の方法において生じていた、水溶性の非ゴム成分を含む排水処理の問題も、解消される。 The solid natural rubber of the present invention is produced by drying natural rubber latex. As the natural rubber latex, a field latex collected by tapping or a latex (high ammonia latex) treated with ammonia added thereto may be used. That is, unlike the conventional method, the solid natural rubber of the present invention is produced without coagulating the natural rubber latex, squeezing the coagulated product, and washing with water. Since squeezing out the water of the coagulated product and washing with water are not performed, the outflow of protein which is a water-soluble non-rubber component is suppressed. That is, the protein originally contained in the natural rubber can be left. In this case, the problem of wastewater treatment including a water-soluble non-rubber component, which has occurred in the conventional method, is also solved.
天然ゴムラテックスの乾燥方法は、特に限定されない。例えば、天然ゴムラテックスをオーブン中で加熱して、乾燥すればよい。熱による天然ゴムの劣化や、生産性を考慮すると、加熱された基材に天然ゴムラテックスを塗布して、または吹き付けて、乾燥することが望ましい。こうすると、乾燥時間を短縮することができる。よって、天然ゴムの熱劣化を抑制することができると共に、生産性が向上する。なかでも、天然ゴムラテックスを吹き付ける方法が、望ましい。吹き付けられた天然ゴムラテックスは、基材表面にドット状に付着する。このため、基材表面に塗布した場合と比較して、比表面積が大きくなり、乾燥しやすい。したがって、天然ゴムラテックスを、より短時間で乾燥させることができる。 The method for drying the natural rubber latex is not particularly limited. For example, natural rubber latex may be heated in an oven and dried. In consideration of degradation of natural rubber due to heat and productivity, it is desirable to apply natural rubber latex to a heated substrate or to spray and dry it. In this way, the drying time can be shortened. Therefore, thermal degradation of natural rubber can be suppressed, and productivity is improved. Among these, a method of spraying natural rubber latex is desirable. The sprayed natural rubber latex adheres to the substrate surface in the form of dots. For this reason, compared with the case where it apply | coats to the base-material surface, a specific surface area becomes large and it is easy to dry. Therefore, the natural rubber latex can be dried in a shorter time.
基材の形状等は、特に限定されない。例えば、基材としてドラム等の回転部材を使用するとよい。この場合、回転部材の加熱された無端環状面（例えばドラムの外周面）に、天然ゴムラテックスを吹き付けて、無端環状面を回転させながら、塗液を乾燥する。そして、得られた固形天然ゴムを、順に無端環状面から剥離すればよい。こうすることにより、天然ゴムラテックスの吹き付け→乾燥→固形天然ゴムの剥離、という一連の工程の自動化が可能となる。したがって、生産性が格段に向上する。 The shape of the substrate is not particularly limited. For example, a rotating member such as a drum may be used as the base material. In this case, natural rubber latex is sprayed onto the heated endless annular surface (for example, the outer peripheral surface of the drum) of the rotating member, and the coating liquid is dried while rotating the endless annular surface. And what is necessary is just to peel the obtained solid natural rubber from an endless annular surface in order. By doing so, it is possible to automate a series of steps of spraying natural rubber latex → drying → peeling solid natural rubber. Therefore, productivity is greatly improved.
基材表面の温度は、１２０℃以上２００℃以下の範囲が望ましい。基材表面の温度が低すぎると、実用的な乾燥時間で、天然ゴムラテックスの乾燥を充分に行うことができない。反対に、基材表面の温度が高すぎると、付着した天然ゴムラテックスが過剰に加熱され、劣化するおそれがある。 The temperature of the substrate surface is desirably in the range of 120 ° C. or higher and 200 ° C. or lower. If the temperature of the substrate surface is too low, the natural rubber latex cannot be sufficiently dried in a practical drying time. On the other hand, if the temperature of the substrate surface is too high, the attached natural rubber latex may be excessively heated and deteriorated.
＜天然ゴム組成物＞
本発明の天然ゴム組成物は、上記本発明の固形天然ゴムを含んで調製される。本発明の固形天然ゴム以外の材料としては、架橋剤、加硫促進剤、酸化亜鉛、加工助剤、補強材、老化防止剤、軟化剤等が挙げられる。架橋剤としては、通常、天然ゴムの架橋に用いられる硫黄（粉末硫黄、沈降硫黄、不溶性硫黄等）、または有機過酸化物を用いればよい。架橋剤として硫黄を用いた場合、硫黄の配合量は、固形天然ゴムの１００質量部に対して、０．３質量部以上７質量部以下であるとよい。より好適には、１質量部以上５質量部以下である。硫黄の配合量が少ないと、架橋を充分に進行させることができない。反対に、硫黄の配合量が多いと、架橋点が多くなり、架橋密度が大きくなる。しかし、架橋点は熱により切断されやすい。このため、硫黄の配合量が多いと、架橋物の耐熱性が低下するおそれがある。この点、本発明の固形天然ゴムによると、残存タンパク質量が多い分、架橋密度が大きい架橋物を製造することができる。したがって、架橋密度を維持しながら、従来より硫黄の配合量を少なくして、架橋物の耐熱性を向上させることができる。
<Natural rubber composition>
The natural rubber composition of the present invention is prepared including the solid natural rubber of the present invention. Examples of materials other than the solid natural rubber of the present invention include a crosslinking agent, a vulcanization accelerator, zinc oxide, a processing aid, a reinforcing material, an antiaging agent, a softening agent, and the like. As the cross-linking agent, sulfur (powder sulfur, precipitated sulfur, insoluble sulfur, etc.) or organic peroxide usually used for cross-linking of natural rubber may be used. When sulfur is used as the crosslinking agent, the amount of sulfur is preferably 0.3 parts by mass or more and 7 parts by mass or less with respect to 100 parts by mass of the solid natural rubber. More preferably, it is 1 part by mass or more and 5 parts by mass or less. If the amount of sulfur is small, the crosslinking cannot proceed sufficiently. On the other hand, when the amount of sulfur is large, the number of crosslinking points increases and the crosslinking density increases. However, the crosslinking point is easily cut by heat. For this reason, when there is much compounding quantity of sulfur, there exists a possibility that the heat resistance of a crosslinked material may fall. In this regard, according to the solid natural rubber of the present invention, a cross-linked product having a high cross-linking density can be produced as the amount of residual protein is large. Therefore, while maintaining the crosslinking density, it is possible to improve the heat resistance of the crosslinked product by reducing the amount of sulfur compared to the conventional one.
本発明の天然ゴム組成物は、本発明の固形天然ゴムに、架橋剤、および必要に応じて加硫促進剤等の添加剤を配合して、バンバリーミキサー、ニーダー、ロール等を用いて混練りすることにより、調製すればよい。 The natural rubber composition of the present invention is kneaded with the solid natural rubber of the present invention using a banbury mixer, a kneader, a roll, or the like by blending a crosslinking agent and, if necessary, an additive such as a vulcanization accelerator. To be prepared.
＜架橋物＞
本発明の架橋物は、上記本発明の天然ゴム組成物を架橋してなる。すなわち、本発明の架橋物を製造するには、本発明の天然ゴム組成物を、例えば１４０〜１７０℃の温度下で５〜３０分間保持して、架橋させればよい。
<Crosslinked product>
The crosslinked product of the present invention is obtained by crosslinking the natural rubber composition of the present invention. That is, in order to produce the crosslinked product of the present invention, the natural rubber composition of the present invention may be crosslinked, for example, by holding at a temperature of 140 to 170 ° C. for 5 to 30 minutes.
次に、実施例を挙げて本発明をより具体的に説明する。 Next, the present invention will be described more specifically with reference to examples.
＜固形天然ゴムの製造＞
天然ゴムラテックスとして、パラゴムノキからタッピングにて採液したフィールドラテックスに、アンモニアを０．５質量％添加したものを使用した。まず、天然ゴムラテックスを、回転するドラムの外周面に吹き付けて、乾燥させた。ドラムの回転速度は、約１ｒｐｍ（１分間に約１回転）であり、ドラムの外周面は、予め約１８０℃に加熱されている。吹き付けられた天然ゴムラテックスの液滴は、ドラムの回転と共に乾燥しながら互いに結着して、シート状に固形化される。次に、ドラムが約３／４回転したところで、形成されたシートを、ドラムの外周面から剥離した。このように、天然ゴムラテックスの吹き付け→乾燥→固形天然ゴムシートの剥離、という一連の工程を繰り返して、固形天然ゴムを製造した。得られた固形天然ゴム中の窒素含有量を、Ｐｅｒｋｉｎ Ｅｌｍｅｒ社製「２４００ＩＩ 全自動元素分析装置（ＣＨＮＳ／Ｏ）」により測定したところ、０．７質量％であった。
<Manufacture of solid natural rubber>
As the natural rubber latex, one obtained by adding 0.5% by mass of ammonia to a field latex collected by tapping from para rubber tree was used. First, natural rubber latex was sprayed on the outer peripheral surface of a rotating drum and dried. The rotation speed of the drum is about 1 rpm (about 1 rotation per minute), and the outer peripheral surface of the drum is heated to about 180 ° C. in advance. The sprayed droplets of natural rubber latex are bonded together while being dried with the rotation of the drum, and are solidified into a sheet. Next, when the drum was rotated about 3/4, the formed sheet was peeled from the outer peripheral surface of the drum. Thus, solid natural rubber was manufactured by repeating a series of steps of spraying natural rubber latex → drying → peeling the solid natural rubber sheet. The nitrogen content in the obtained solid natural rubber was measured by “2400II fully automatic elemental analyzer (CHNS / O)” manufactured by Perkin Elmer, and found to be 0.7% by mass.
＜天然ゴム組成物の調製および架橋物の製造＞
（１）補強材無しの場合
［実施例１］
まず、製造した固形天然ゴムを用い、ＪＩＳ Ｋ６３５２（２００５）の５．１の表１に規定される標準配合に従って、天然ゴム組成物を調製した。すなわち、固形天然ゴム１００質量部と、酸化亜鉛２種（堺化学工業（株）製）６質量部と、加工助剤のステアリン酸（花王（株）製「ルナック（登録商標）Ｓ３０」）０．５質量部と、加硫促進剤（三新化学工業（株）製「サンセラー（登録商標）ＮＳ−Ｇ」）０．７質量部と、硫黄（鶴見化学工業（株）製「サルファックスＴ−１０」）３．５質量部と、をロールを用いて混練して、天然ゴム組成物を調製した。調製した天然ゴム組成物を、実施例１の組成物とした。
<Preparation of natural rubber composition and production of crosslinked product>
(1) When there is no reinforcing material [Example 1]
First, using the produced solid natural rubber, a natural rubber composition was prepared according to the standard composition defined in Table 1 of 5.1 of JIS K6352 (2005). That is, 100 parts by mass of solid natural rubber, 6 parts by mass of zinc oxide (produced by Sakai Chemical Industry Co., Ltd.) and stearic acid as a processing aid ("Lunac (registered trademark) S30" produced by Kao Corporation) 0 .5 parts by mass, 0.7 parts by mass of a vulcanization accelerator (“Sanseller (registered trademark) NS-G” manufactured by Sanshin Chemical Industry Co., Ltd.) and sulfur (“Sulfax T” manufactured by Tsurumi Chemical Industry Co., Ltd.) −10 ”) and 3.5 parts by mass were kneaded using a roll to prepare a natural rubber composition. The prepared natural rubber composition was used as the composition of Example 1.
次に、実施例１の組成物を１６０℃±０．３℃下で架橋して、架橋時間に対するトルクの変化（架橋曲線）を測定した。測定は、（株）東洋精機製作所製のロータレス式レオメータ試験機を使用して、ＪＩＳ Ｋ６３００−２（２００１）に準じて行った。振幅角度は１°とした。 Next, the composition of Example 1 was crosslinked at 160 ° C. ± 0.3 ° C., and the change in torque with respect to the crosslinking time (crosslinking curve) was measured. The measurement was performed according to JIS K6300-2 (2001) using a rotorless rheometer tester manufactured by Toyo Seiki Seisakusho. The amplitude angle was 1 °.
これとは別に、実施例１の組成物を、１４０℃下、四種類の時間（２０分、３０分、４０分、６０分）で架橋して、架橋物を製造した。そして、得られた架橋物から、ＪＩＳ Ｋ ６２５１（２０１０）に規定されるダンベル状５号形の試験片を作製し、同ＪＩＳに規定される引張試験を行った。 Separately from this, the composition of Example 1 was crosslinked at 140 ° C. for four types of time (20 minutes, 30 minutes, 40 minutes, 60 minutes) to produce a crosslinked product. And the dumbbell-shaped No. 5 type test piece prescribed | regulated to JISK6251 (2010) was produced from the obtained crosslinked material, and the tension test prescribed | regulated to the same JIS was done.
［比較例１−１］
製造した固形天然ゴムに代えて、従来の方法により製造された固形天然ゴム「ＲＳＳ＃３」を素練りしたものを用いた以外は、実施例１と同様にして、比較例１−１の組成物を調製した。使用した固形天然ゴム中の窒素含有量は、０．５質量％であった。そして、比較例１−１の組成物を、実施例１と同様に１６０℃±０．３℃下で架橋して、架橋時間に対するトルクの変化を測定した。また、比較例１−１の組成物を、１４０℃下、実施例１と同じ四種類の時間で架橋して、架橋物を製造した。そして、実施例１と同様に、得られた架橋物の引張試験を行った。
[Comparative Example 1-1]
The composition of Comparative Example 1-1 was the same as in Example 1, except that a solid natural rubber “
［比較例１−２］
製造した固形天然ゴムに代えて、従来の方法により製造された固形天然ゴム「ＣＶ（Ｃｏｎｓｔａｎｔ Ｖｉｓｃｏｓｉｔｙ）５０」を用いた以外は、実施例１と同様にして、比較例１−２の組成物を調製した。使用した固形天然ゴム中の窒素含有量は、０．５質量％であった。そして、比較例１−２の組成物を、実施例１と同様に１６０℃±０．３℃下で架橋して、架橋時間に対するトルクの変化を測定した。また、比較例１−２の組成物を、１４０℃下、実施例１と同じ四種類の時間で架橋して、架橋物を製造した。そして、実施例１と同様に、得られた架橋物の引張試験を行った。
[Comparative Example 1-2]
The composition of Comparative Example 1-2 was used in the same manner as in Example 1 except that the solid natural rubber “CV (Constant Viscosity) 50” produced by a conventional method was used instead of the produced solid natural rubber. Prepared. The nitrogen content in the solid natural rubber used was 0.5% by mass. And the composition of the comparative example 1-2 was bridge | crosslinked under 160 degreeC +/- 0.3 degreeC similarly to Example 1, and the change of the torque with respect to crosslinking time was measured. Moreover, the composition of Comparative Example 1-2 was crosslinked at 140 ° C. for the same four types of times as in Example 1 to produce a crosslinked product. And the tensile test of the obtained crosslinked material was done like Example 1. FIG.
（２）補強材有りの場合
［実施例２］
実施例１の組成物を調製した材料に、さらに、補強材のカーボンブラック（ＨＡＦ）３５質量部を加えて、実施例２の組成物を調製した。この場合、酸化亜鉛２種の配合量を５質量部、ステアリン酸の配合量を２質量部、硫黄の配合量を２．２５質量部に、変更した。本配合も、ＪＩＳ Ｋ６３５２（２００５）の５．１の表１に規定される標準配合に従うものである。そして、実施例１と同様に、実施例２の組成物を架橋して、架橋曲線の測定および架橋物の引張試験を行った。
(2) When there is a reinforcing material [Example 2]
The composition of Example 2 was prepared by adding 35 parts by mass of reinforcing material carbon black (HAF) to the material from which the composition of Example 1 was prepared. In this case, the amount of the two types of zinc oxide was changed to 5 parts by mass, the amount of stearic acid was changed to 2 parts by mass, and the amount of sulfur was changed to 2.25 parts by mass. This composition is also in accordance with the standard composition defined in Table 1 of 5.1 of JIS K6352 (2005). And like Example 1, the composition of Example 2 was bridge | crosslinked and the measurement of the crosslinking curve and the tensile test of the crosslinked material were done.
［比較例２−１］
比較例１−１の組成物を調製した材料に、さらに、補強材のカーボンブラック（ＨＡＦ）３５質量部を加えて、比較例２−１の組成物を調製した。この場合、実施例２と同様に、酸化亜鉛２種の配合量を５質量部、ステアリン酸の配合量を２質量部、硫黄の配合量を２．２５質量部に、変更した。そして、比較例１−１と同様に、比較例２−１の組成物を架橋して、架橋曲線の測定および架橋物の引張試験を行った。
[Comparative Example 2-1]
To the material from which the composition of Comparative Example 1-1 was prepared, 35 parts by mass of reinforcing material carbon black (HAF) was further added to prepare the composition of Comparative Example 2-1. In this case, similarly to Example 2, the blending amount of the two types of zinc oxide was changed to 5 parts by mass, the blending amount of stearic acid was changed to 2 parts by mass, and the blending amount of sulfur was changed to 2.25 parts by mass. And like the comparative example 1-1, the composition of the comparative example 2-1 was bridge | crosslinked, the measurement of the crosslinking curve and the tensile test of the crosslinked material were performed.
［比較例２−２］
比較例１−２の組成物を調製した材料に、さらに、補強材のカーボンブラック（ＨＡＦ）３５質量部を加えて、比較例２−２の組成物を調製した。この場合、実施例２と同様に、酸化亜鉛２種の配合量を５質量部、ステアリン酸の配合量を２質量部、硫黄の配合量を２．２５質量部に、変更した。そして、比較例１−２と同様に、比較例２−２の組成物を架橋して、架橋曲線の測定および架橋物の引張試験を行った。
[Comparative Example 2-2]
To the material from which the composition of Comparative Example 1-2 was prepared, 35 parts by mass of reinforcing material carbon black (HAF) was further added to prepare the composition of Comparative Example 2-2. In this case, similarly to Example 2, the blending amount of the two types of zinc oxide was changed to 5 parts by mass, the blending amount of stearic acid was changed to 2 parts by mass, and the blending amount of sulfur was changed to 2.25 parts by mass. And like the comparative example 1-2, the composition of the comparative example 2-2 was bridge | crosslinked and the measurement of the crosslinking curve and the tensile test of the crosslinked material were done.
＜架橋特性の評価＞
まず、補強材を含まない組成物の架橋特性について説明する。図１に、補強材無しの各組成物を架橋した場合の架橋曲線を示す。図１に示す架橋曲線からわかるように、本発明の固形天然ゴムを用いた実施例１の組成物を架橋した場合、従来の固形天然ゴムを用いた比較例１−１、１−２の組成物を架橋した場合と比較して、トルクの上昇が速くなり、かつ、トルクの最大値も大きくなった。このことは、ｔｃ（１０）に対して最大トルク値をプロットした図２のグラフからも明らかである。ここで、ｔｃ（１０）は、１０％架橋時間（架橋開始点）である。図２に示すように、実施例１の組成物を架橋した場合において、ｔｃ（１０）が最も短くなり、かつ、最大トルク値が最も大きくなった。これより、実施例１の組成物の架橋速度は、比較例１−１、１−２の組成物の架橋速度よりも、大きいことがわかる。また、実施例１の架橋物の架橋密度は、比較例１−１、１−２の架橋物の架橋密度よりも、大きいことがわかる。
<Evaluation of cross-linking properties>
First, the cross-linking characteristics of a composition that does not contain a reinforcing material will be described. FIG. 1 shows a cross-linking curve when each composition without a reinforcing material is cross-linked. As can be seen from the cross-linking curve shown in FIG. 1, when the composition of Example 1 using the solid natural rubber of the present invention is cross-linked, the compositions of Comparative Examples 1-1 and 1-2 using the conventional solid natural rubber are used. Compared to the case where the product was cross-linked, the increase in torque was faster and the maximum value of torque was also increased. This is apparent from the graph of FIG. 2 in which the maximum torque value is plotted against t c (10). Here, t c (10) is 10% crosslinking time (crosslinking start point). As shown in FIG. 2, when the composition of Example 1 was crosslinked, t c (10) was the shortest and the maximum torque value was the largest. From this, it can be seen that the crosslinking rate of the composition of Example 1 is larger than the crosslinking rate of the compositions of Comparative Examples 1-1 and 1-2. Moreover, it turns out that the crosslinking density of the crosslinked material of Example 1 is larger than the crosslinking density of the crosslinked material of Comparative Examples 1-1 and 1-2.
次に、補強材を含む組成物の架橋特性について説明する。図３に、補強材有りの各組成物を架橋した場合の架橋曲線を示す。図４に、補強材有りの各組成物を架橋した場合のｔｃ（１０）に対して最大トルク値をプロットしたグラフを示す。図３、図４からわかるように、補強材を含む場合においても、本発明の固形天然ゴムを用いた実施例２の組成物を架橋した場合、従来の固形天然ゴムを用いた比較例２−１、２−２の組成物を架橋した場合と比較して、トルクの上昇が速くなった。換言すると、ｔｃ（１０）が短くなった。一方、実施例２の組成物を架橋した場合のトルクの最大値は、比較例２−２よりは大きくなったが、比較例２−１との間に差は見られなかった。これは、カーボンブラックによる補強性が発現されたためと考えられる。 Next, the crosslinking characteristics of the composition containing the reinforcing material will be described. FIG. 3 shows a cross-linking curve when each composition having a reinforcing material is cross-linked. FIG. 4 shows a graph in which the maximum torque value is plotted against t c (10) when each composition with a reinforcing material is crosslinked. As can be seen from FIGS. 3 and 4, when the composition of Example 2 using the solid natural rubber of the present invention is crosslinked even when the reinforcing material is included, Comparative Example 2 using the conventional solid natural rubber is used. Compared with the case where the composition of 1 and 2-2 was bridge | crosslinked, the raise of torque became quick. In other words, t c (10) was shortened. On the other hand, the maximum value of the torque when the composition of Example 2 was crosslinked was larger than that of Comparative Example 2-2, but no difference was observed between Comparative Example 2-1. This is thought to be due to the reinforcement of carbon black.
以上より、本発明の固形天然ゴムは、架橋特性に優れることが確認された。すなわち、本発明の固形天然ゴムを用いると、架橋速度が大きくなり、架橋密度が大きい架橋物を製造できることが確認された。 From the above, it was confirmed that the solid natural rubber of the present invention was excellent in cross-linking properties. That is, it was confirmed that when the solid natural rubber of the present invention is used, a crosslinked product having a high crosslinking rate and a high crosslinking density can be produced.
＜引張特性の評価＞
図５に、補強材無しの各架橋物における架橋時間と１００％伸び引張応力（１００％モジュラス）との関係を示す。図６に、補強材有りの各架橋物における架橋時間と１００％モジュラスとの関係を示す。
<Evaluation of tensile properties>
FIG. 5 shows the relationship between the crosslinking time and 100% elongation tensile stress (100% modulus) in each crosslinked product without a reinforcing material. FIG. 6 shows the relationship between the crosslinking time and 100% modulus in each crosslinked product with a reinforcing material.
図５、図６に示すように、補強材の有無に関わらず、実施例１、２の架橋物においては、架橋時間が短くても、１００％モジュラスが大きくなった。また、同じ架橋時間で比較した場合、実施例１の架橋物は比較例１−１、１−２の架橋物よりも、実施例２の架橋物は比較例２−１、２−２の架橋物よりも、１００％モジュラスが大きくなった。このように、本発明の固形天然ゴムを用いると、架橋時間が短くても、強度が大きい架橋物を得られることが確認された。 As shown in FIGS. 5 and 6, regardless of the presence or absence of the reinforcing material, the crosslinked products of Examples 1 and 2 had a large 100% modulus even when the crosslinking time was short. In addition, when compared at the same crosslinking time, the crosslinked product of Example 1 was compared with the crosslinked products of Comparative Examples 1-1 and 1-2, and the crosslinked product of Example 2 was crosslinked with Comparative Examples 2-1 and 2-2. 100% modulus was larger than the product. Thus, it was confirmed that when the solid natural rubber of the present invention is used, a crosslinked product having a high strength can be obtained even if the crosslinking time is short.
本発明の固形天然ゴムによると、架橋時間を短縮することができ、架橋密度および強度が大きい架橋物を製造することができる。したがって、本発明の固形天然ゴムは、ゴム製品の製造原料として有用である。 According to the solid natural rubber of the present invention, the crosslinking time can be shortened, and a crosslinked product having a high crosslinking density and strength can be produced. Therefore, the solid natural rubber of the present invention is useful as a raw material for producing rubber products.
Claims (5)
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2012038436A JP5876322B2 (en) | 2012-02-24 | 2012-02-24 | Solid natural rubber, natural rubber composition and cross-linked product using the same |
| MYPI2014701025A MY167863A (en) | 2012-02-24 | 2013-02-13 | Solid natural rubber, natural rubber composition using the same, and cross-linked product |
| PCT/JP2013/053424 WO2013125416A1 (en) | 2012-02-24 | 2013-02-13 | Solid natural rubber, natural rubber composition using same, and crosslinking product |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2012038436A JP5876322B2 (en) | 2012-02-24 | 2012-02-24 | Solid natural rubber, natural rubber composition and cross-linked product using the same |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2015181764A Division JP5977413B2 (en) | 2015-09-15 | 2015-09-15 | Method for producing solid natural rubber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2013173829A true JP2013173829A (en) | 2013-09-05 |
| JP5876322B2 JP5876322B2 (en) | 2016-03-02 |
Family
ID=49005603
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2012038436A Active JP5876322B2 (en) | 2012-02-24 | 2012-02-24 | Solid natural rubber, natural rubber composition and cross-linked product using the same |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JP5876322B2 (en) |
| MY (1) | MY167863A (en) |
| WO (1) | WO2013125416A1 (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0489847A (en) * | 1990-08-03 | 1992-03-24 | Japan Synthetic Rubber Co Ltd | Production of natural rubber composition |
| JP2004514009A (en) * | 2000-11-07 | 2004-05-13 | 株式会社ブリヂストン | Natural rubber from latex and compositions containing it |
| JP2008263806A (en) * | 2007-04-17 | 2008-11-06 | Bridgestone Corp | Enzyme-treated latex, enzyme-treated natural rubber, enzyme-treated natural rubber composition and method for producing enzyme-treated latex |
-
2012
- 2012-02-24 JP JP2012038436A patent/JP5876322B2/en active Active
-
2013
- 2013-02-13 WO PCT/JP2013/053424 patent/WO2013125416A1/en active Application Filing
- 2013-02-13 MY MYPI2014701025A patent/MY167863A/en unknown
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0489847A (en) * | 1990-08-03 | 1992-03-24 | Japan Synthetic Rubber Co Ltd | Production of natural rubber composition |
| JP2004514009A (en) * | 2000-11-07 | 2004-05-13 | 株式会社ブリヂストン | Natural rubber from latex and compositions containing it |
| JP2008263806A (en) * | 2007-04-17 | 2008-11-06 | Bridgestone Corp | Enzyme-treated latex, enzyme-treated natural rubber, enzyme-treated natural rubber composition and method for producing enzyme-treated latex |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2013125416A1 (en) | 2013-08-29 |
| JP5876322B2 (en) | 2016-03-02 |
| MY167863A (en) | 2018-09-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2007049460A1 (en) | Process for producing natural rubber reduced in viscosity, natural rubber reduced in viscosity obtained by the process, and rubber composition containing the same | |
| CN102719025B (en) | High temperature resistance odorless peroxide rubber composition and preparation method thereof | |
| CN104313880B (en) | Heat-resistant dipping treatment liquid for polyester canvas and preparation method and application thereof | |
| CN110832024A (en) | Rubber compound for pneumatic tire containing regenerated carbon black | |
| CN103146084A (en) | Composition as well as preparation method and application thereof | |
| BE1001175A3 (en) | Dynamically cured thermoplastic elastomer. | |
| JP5977413B2 (en) | Method for producing solid natural rubber | |
| JP5876322B2 (en) | Solid natural rubber, natural rubber composition and cross-linked product using the same | |
| CN105639777A (en) | Wear-resistant flannelette nitrile gloves and preparation technology thereof | |
| CN1568342A (en) | Mold release and anti-blocking coating for powder-free natural or synthetic rubber articles | |
| JP2012121946A (en) | Solid natural rubber, and method for producing the same | |
| TW201905059A (en) | Vulcanizable composition comprising hxnbr latex and polyfunctional epoxide | |
| CN104610665B (en) | Rubber plastic blend compositionss, dynamic vulcanization thermoplastic elastomer and preparation method | |
| CN102975321A (en) | Method for preparing condom by using polyisoprene rubber latex | |
| JPS6024131B2 (en) | Method of adhering fibers and hydrogenated nitrile rubber compounds | |
| JP2006232880A (en) | Rubber composition | |
| JP6278847B2 (en) | Method for producing rubber composition, rubber composition, cushion rubber and retreaded tire | |
| CN105542245A (en) | High-performance rubber produced through rubber refining of high-thermal-stability insoluble sulfur and preparation method | |
| US1098882A (en) | Manufacture of rubber compounds. | |
| JP2006199142A (en) | Tire steel cord coating compound | |
| JP2009001774A (en) | Method for producing natural rubber | |
| TWI787840B (en) | Emulsion auxiliary composition for producing emulsion solution | |
| JP5759399B2 (en) | Anti-vibration rubber composition and anti-vibration rubber member | |
| CN106634236A (en) | Formula of non asphalt-based non-cured coating and preparation process of non asphalt-based non-cured coating | |
| CN108440871A (en) | A kind of antistatic bamboo moulding material and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20140318 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20141028 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20141217 |
|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20150616 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20150915 |
|
| A911 | Transfer of reconsideration by examiner before appeal (zenchi) |
Free format text: JAPANESE INTERMEDIATE CODE: A911 Effective date: 20150925 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20151124 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20160105 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20160121 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 5876322 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |