JP2004300271A - Member for fluid piping - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a member for fluid(e.g. water) piping, particularly a member for jointing use, causing neither breakage, burst, nor the like, on freezing even if the piping is exposed to very-low-temperature outside air, thus high in low-temperature breakage resistance. <P>SOLUTION: This member for the fluid piping comprises a resin composition comprising (A) a polyarylene sulfide resin and (B) a thermoplastic elastomer such as a polyolefin elastomer or a nitrile elastomer, wherein the tensile elongation percentage of the resin composition is 25-300% at 25°C. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００１０】
前記ＰＡＳ樹脂（Ａ）には、他の共重合体構成単位を含有させることができる。この含有可能な共重合体構成単位の具体例としては、特に制限されるものではないが、例えば、下記構造式（２）で表されるメタ結合、下記構造式（３）で表されるエ−テル結合、下記構造式（４）で表されるスルホン結合、下記構造式（５）で表される、スルフィドケトン結合、下記構造式（６）で表されるビフェニル結合、下記構造式（７）で表される置換フェニルスルフィド結合、下記構造式（８）で表される３官能フェニルスルフィド結合及びナフチル結合等が挙げられる。
【００１１】
【化２】

（式中、Ｒはアルキル基、ニトロ基、アミノ基、フェニル基、アルコキシ基、を示す。）
【００１２】
本発明で用いるＰＡＳ樹脂（Ａ）は、前記一般式（１）で表される繰り返し単位を７０モル％以上含有するＰＰＳ樹脂であることが、耐熱性、機械特性に優れたポリマーとしての特徴が発揮されやすいため好ましい。
【００１３】
前記ＰＡＳ樹脂（Ａ）を得る方法としては、特に限定されないが、ＰＰＳ樹脂を例にとると、（１）ジハロゲン芳香族化合物類を硫黄と炭酸ソーダの存在下に重合させる方法、（２）ジハロゲン芳香族化合物類を極性溶媒中でスルフィド化剤の存在下に重合させる方法、（３）ｐ−クロルチオフェノールを自己縮合させる方法、（４）有機極性溶媒とジハロゲノ芳香族化合物を混合し加熱しておき、その中に含水スルフィド化剤を加えてジハロゲノ芳香族化合物とスルフィド化剤とを反応させ、このとき、含水スルフィド化剤を反応混合物中の水分量が有機極性溶媒の２〜５０モル％の範囲内になる様な速度で加える製造方法（特開平０７−２２８６９９号公報）等が挙げられる。
【００１４】
これらの中でも前記（４）の製造方法が分子量の大きなＰＰＳ樹脂を得ること容易で、そのため樹脂組成物の引張伸び率が２５〜３００％にとなりやすい点から好ましい。
【００１５】
本発明に用いるＰＡＳ樹脂（Ａ）の分子量は、１−クロロナフタレンを溶媒として、ゲル浸透クロマトグラフィーにより求めることが出来る。前記ＰＡＳ樹脂（Ａ）は、低温での耐衝撃性、強靭性の向上が顕著であることからそのピーク分子量が、３５０００以上が好ましく、さらに成形時の流動性が良好であることから２０００００以下が好ましく、中でも、４００００〜１０００００が特に好ましい。
【００１６】
前記ＰＡＳ樹脂（Ａ）の分子量は、一般に分子量分布が非常に大きく、さらにピーク分子量の左右のテーリングが製造条件で大きく振れる傾向がある。その為、数平均分子量と重量平均分子量の差が大きくどちらを用いても実情を表さない場合があり、分子量分布の中で最も多数の分子が集まった分子量を示すピーク分子量が、比較的性能に直接反映される事を知り、ピーク分子量で評価する事にした。このピーク分子量の測定法は実施例で詳述する。
【００１７】
前記ＰＡＳ樹脂（Ａ）の分子量は高い程、後述する熱可塑エラストマー（Ｂ）との均一混合を容易にする。この均一分散性は耐衝撃性や強靭性の向上に不可欠であり、より好ましい方向になる。
【００１８】
本発明に使用される熱可塑性エラストマー（Ｂ）は、ＰＡＳ樹脂（Ａ）を混練する温度で、溶融し混合分散可能であることが好ましい。その点から、融点が３００℃以下であり、室温でゴム弾性を有するエラストマーが好ましい。また、耐熱性、混合の容易さ、耐衝撃性の向上の点で、ポリオレフィン系エラストマー類またはニトリル系エラストマー類が好ましい。
【００１９】
前記ポリオレフィン系エラストマーとしては、水酸基、カルボキシル基、アミノ基、メルカプト基、エポキシ基、酸無水物基、イソシアネート基、エステル基、ビニル基等の官能基を有するものが好ましい、
【００２０】
また、更にこれらの中でも、酸無水物、酸、エステル等のカルボン酸に起因する官能基又はエポキシ基が特に好ましい。
【００２１】
前記ポリオレフィン系エラストマーとしては、例えば、α−オレフィン類と前記官能基を有するビニル重合性化合物類との共重合で得ることが出来る。前記α−オレフィン類としては、例えば、エチレン、プロピレン、ブテン−等の炭素数２〜８のα−オレフィン類等が挙げられる。また、前記官能基を有するビニル重合性化合物類としては、例えば、アクリル酸、メタクリル酸、アクリル酸エステル、メタクリル酸エステル類等のα，β―不飽和カルボン酸類及びそのアルキルエステル類、マレイン酸、フマル酸、イタコン酸、その他炭素数４〜１０の不飽和ジカルボン酸とそのモノ及びジエステル類、及びその酸無水物等のα，β―不飽和ジカルボン酸及びその無水物、グリシジル（メタ）アクリレート等が挙げられる。
【００２２】
これらの官能基類を複数個、同時に含有した共重合体を用いることができる。これらの好ましい例としては、α−オレフィン類、無水マレイン酸、アクリル酸グリシジルの三元共重合体が挙げられる。
【００２３】
前記ニトリル系エラストマーがある。アクリロニトリル、メタクリロニトリル等の様な不飽和結合を有するニトリルと共役二重結合を有するブタジエン、メチルブタジエン等との共重合により得ることが出来る。この共重合体は二重結合の一部または全部を水素添加して耐熱性を高めたタイプは更に好ましい。
【００２４】
これらの官能基を含んだ熱可塑性エラストマー（Ｂ）は、ＰＡＳ樹脂（Ａ）との分散性が良好になり、均一混合された樹脂組成物を得ることが容易になり、耐低温破断性などが向上する。
【００２５】
前記ＰＡＳ樹脂（Ａ）と熱可塑性エラストマー（Ｂ）との配合割合は、（Ａ）／（Ｂ）＝５０／５０〜９９／１（重量比）であることが、組成物の引張伸び率が２５〜３００％の範囲に入ることから好ましく、８０／２０〜９７／３が特に好ましい。
【００２６】
本発明に用いる樹脂組成物には、樹脂組成物の引張伸び率が２５〜３００％となる範囲で各種強化材、充填材、潤滑剤、安定剤などの添加成分を添加使用することが出来る。これらの添加成分の添加量は、特に限定されないが、組成物１００重量部当たり、それぞれ５重量部以下が好ましい。
【００２７】
本発明に用いる樹脂組成物は、例えば、次の方法で調製することができる。
前記ＰＡＳ樹脂（Ａ）と熱可塑性エラストマー（Ｂ）とをヘンシェルミキサー、又はタンブラー等のミキサーで予め混合しておき、１軸又は２軸の押出混練機に挿入して２００〜３５０℃で混練りし、造粒しペレット化して調製する。この樹脂組成物の調整法は特に限定された物でなく、材料の添加時期、順序、混合機、押出機の種類、大きさ等限定されるものではない。
【００２８】
本発明の流体配管用部材は、前記樹脂組成物を成形して得る。これら流体配管部材としては、例えばパイプ、ライニング管、袋ナット類、管継ぎ手類（エルボー、ヘッダー、チーズ、レデューサ、ジョイント、カプラー、等）、各種バルブ、流量計、ガスケット（シール、パッキン類）、など流体を搬送する為の配管及び配管に付属する各種の部品が挙げられる。
【００２９】
又、本発明の流体配管用部材は樹脂組成物単独で成形され使用することが出来るが、他の材料と複合化したり、共押し出し等の様な同時成形を取ったり、又接着、カシメ等により、他材料と合わせて、又その一部として使用することも出来、その使用形態は限定されない。
【００３０】
本発明の課題である低温氷結時の配管部材の耐破断性評価は−２０℃で内部の水を氷結させて破断の有無を確認して行うが、具体的方法は実施例に記載する。又、その性能に大きく影響する引張伸び率は、ＡＳＴＭ Ｄ−６３８に従い測定し評価した。
【００３１】
以下、本発明に関して、実施例及び比較例により説明する。
【００３２】
〈測定方法及び評価方法〉
１．ピーク分子量の測定
測定対象のＰＰＳ樹脂をゲル浸透クロマトグラフにて測定した。
装置；超高温ポリマー分子量分布測定装置（センシュウ科学社製ＳＳＣ−７０００）
カラム ；ＵＴ−８０５Ｌ（昭和電工社製）
カラム温度；２１０℃
溶媒 ；１−クロロナフタレン
ＵＶ検出器（３６０ｎｍ）で６種類の単分散ポリスチレンを校正に用いて分子量分布とピーク分子量を測定した。
【００３３】
２．引張特性−伸び率の測定
測定対象樹脂配合物の試験片をＡＳＴＭ４号ダンベル形状で作成し、ＡＳＴＭＤ６３８に従って、島津製作所製“オートグラフ ＡＧ−５０００Ｃ”にて測定し、引張強さ及び引張破断伸びを測定した。
【００３４】
３．耐充満水凍結試験−耐低温破断性の測定
評価対象樹脂配合物から、両端部がフランジ及びネジ構造で密閉出来る内径２２ｍｍ、外径２８ｍｍ、の円筒形状の管継ぎ手を射出成形で作成した。
この中に空気層を含まない様、水中にて水を充填し、両端を密閉した後、水から出して、−２０℃の冷凍庫に入れ、２時間放置し、内部の水を完全に凍らせた。その後冷凍庫より取り出して、管継ぎ手の割れを調べて耐低温破断性の評価を行った。
４．ムーニー粘度の測定
ＪＩＳ Ｋ−６３００ に従い測定した。
測定条件；ローター Ｌ型 予備 １分、作動 ４分、１００℃
５．ＭＦＲの測定
ＪＩＳ Ｋ−６７００ に従い測定した。
【００３５】
合成例１
［含水スルフィド化剤の作成］
以下材料を混合して含水スルフィド化剤を作成した。
（１）含水フレーク状硫化ナトリウム（ナガオ製） ；１．５ｋｇ［純度／Ｎａ_２Ｓ（５８．９重量％）、ＮａＳＨ（１．３重量％）］
（２）含水フレーク状水硫化ナトリウム（ナガオ製）；０．２２５ｋｇ［純度／ＮａＳＨ（７１．２重量％）、Ｎａ２Ｓ（２．７重量％）］
（３）水 ；０．４２５ｋｇ
以上３種類を混合して含水スルフィド化剤 ２．１５ｋｇを作成した。
【００３６】
［ＰＰＳ樹脂の合成］
温度センサー、冷却器、滴下槽、溜出物分離槽、攪拌翼を備えた反応槽にパラジクロロベンゼン（１．８３８ｋｇ）、Ｎ−メチル−２−ピロリドン（４．９５８ｋｇ）、水（０．０９ｋｇ）を仕込み、窒素雰囲気下で攪拌しながら１００℃迄昇温する。反応槽を密封した後２２０℃、内圧を０．２２ＭＰａとして、上記含水スルフィド化剤（２．１５ｋｇ）を滴下した。滴下反応中に脱水を行い、共出するパラジクロロベンゼンは反応槽に戻し、水を系外に出す事によって、系中の水量がＮ−メチル−２−ピロリドン１モルに対し０．０２〜０．５モルとなるよう調節して反応させた。反応は昇温により、２４０℃になる迄行い、その後、２４０℃で１時間保持して反応を終了した。反応終了時に水は極性溶剤（Ｎ−メチル−２−ピロリドン）の０．１７モル％であることを確認した。当ポリマーは反応中及び反応終了時も水は極性溶剤１モルに対し、０．０２〜０．５モル範囲であった事を確認した。得られた反応物を水洗し、乾燥して白色粉末のポリマーを得た。このポリマーを“ＰＰＳ−１”とする。ＰＰＳ−１はピーク分子量４０７００であった。
【００３７】
実施例１〜５、及び比較例１
樹脂配合物ペレットは表１中の材料を均一に混合した後、３５ｍｍφの２軸押出機を用い２９０〜３３０℃で混練りした後、ペレット化して得た。次いで、このペレットをインラインスクリュー式射出成型機で、シリンダー温度２９０〜３２０℃、金型温度１３０℃、射出圧力８０〜１００ＭＰａ、で引っ張り試験用試験片及び低温耐破断性を評価する為の管継ぎ手を成形した。次いで、前述の評価方法で低温耐破断性を評価した。得られた結果を表１に示す。
【００３８】
【表１】

【００３９】
表中の各成分は下記のものを使用した。
ＰＰＳ−２；ＰＰＳ（ピーク分子量３４，２００［大日本インキ化学工業社製（ＬＲ−２Ｇ）］）
ＰＰＳ−３；ＰＰＳ（ピーク分子量１６，０００［大日本インキ化学工業社製（Ｂ−１００−Ｃ）］）
ＥＬＡ−１；グリシジルメタアクリレート（３重量％）、アクリル酸メチル（３０重量％）、エチレン（６７重量％）から成るポリオレフィン系エラストマー。ＭＦＲ＝９
ＥＬＡ−２；熱可塑性エラストマー；無水マレイン酸（２重量％）、アクリル酸エチル（３１重量％）、エチレン（６７重量％）から成るポリオレフィン系エラストマー。ＭＦＲ＝７
ＥＬＡ−３；ヨウ素価が４ｇ／１００ｇのアクリルニトリル含有量（３６重量％）、カルボキシル基含有モノマー（５重量％）から成る水素添加アクリロニトリルーブタジエン共重合体。（日本ゼオン社製）ムーニー粘度＝８５
【００４０】
【発明の効果】
本発明によれば、極低温の屋外での低温耐破断性が良好な配管用部材を提供できる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to various organic / inorganic fluids, various solvents, fuels, various gases, liquefied gases, fluids having fluidity such as raw materials, intermediates, and products for producing various polymers, or drinking water, Fluid piping members useful for conveying mainly water-containing fluids, such as warm water via hot water heaters, floor heating systems based on warm water, and fertilizer blended water supply systems for plant grown vegetables, etc., especially joint members About.
[0002]
[Prior art]
Recently, plastics have been used for piping members instead of metal materials. For the plastic material, for example, high-density polyethylene, cross-linked polyethylene, or the like is used as a pipe member such as a pipe, but these plastics lack heat resistance, and in a structure having a joint particularly due to heat of a fluid. There have been problems such as loosening of the joint and breakage or rupture of the piping due to freezing. In order to improve this, a technique using a polyphenylene sulfide resin composition has been proposed (for example, see Patent Document 1). However, even with this method, the effect of improving the above-mentioned breakage, rupture and the like due to icing was insufficient.
[0003]
[Patent Document 1]
JP 2001-11520 A (pages 2 to 5)
[0004]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to provide a fluid pipe member having good low-temperature rupture resistance, particularly a joint member, which does not cause breakage or rupture due to icing even when the pipe is exposed to cryogenic outside air. is there.
[0005]
[Means for Solving the Problems]
As a result of intensive studies to solve the above problems, the following findings were obtained. A fluid piping member using a composition in which the elongation of a molded article of a resin composition containing a polyarylene sulfide resin (A) and a thermoplastic elastomer (B) is controlled to 25 to 300% (25 ° C.) The low temperature rupture resistance is improved. The present invention is based on such findings.
[0006]
That is, the present invention relates to a fluid piping member comprising a resin composition containing a polyarylene sulfide resin (A) and a thermoplastic elastomer (B), wherein the tensile elongation of the resin composition at 25 ° C. Is 25 to 300%.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
It is essential that the resin composition used in the present invention has a tensile elongation at 25 ° C. of 25 to 300%. Here, when the tensile elongation is less than 25%, the low-temperature rupture resistance described below is undesirably reduced. On the other hand, if the tensile elongation is more than 300%, there is a possibility of deformation due to a strong local external force, which is not preferable.
[0008]
The polyarylene sulfide resin (A) (hereinafter abbreviated as PAS resin) (A) used in the present invention is a so-called polyphenylene sulfide resin (hereinafter, referred to as PPS resin) having a repeating unit represented by the following general formula (1). Is abbreviated.) From the viewpoint of good heat resistance, mechanical properties and chemical resistance.
[0009]
Embedded image

[0010]
The PAS resin (A) may contain another copolymer constituent unit. Specific examples of the copolymer constituent units that can be contained are not particularly limited, but examples thereof include a meta bond represented by the following structural formula (2) and an epoxy group represented by the following structural formula (3). -A ter bond, a sulfone bond represented by the following structural formula (4), a sulfide ketone bond represented by the following structural formula (5), a biphenyl bond represented by the following structural formula (6), and a following structural formula (7) ), A trifunctional phenyl sulfide bond and a naphthyl bond represented by the following structural formula (8).
[0011]
Embedded image

(In the formula, R represents an alkyl group, a nitro group, an amino group, a phenyl group, or an alkoxy group.)
[0012]
The PAS resin (A) used in the present invention is a PPS resin containing the repeating unit represented by the general formula (1) in an amount of 70 mol% or more, and has a characteristic as a polymer having excellent heat resistance and mechanical properties. It is preferable because it is easily exhibited.
[0013]
The method for obtaining the PAS resin (A) is not particularly limited. For example, in the case of a PPS resin, (1) a method of polymerizing a dihalogen aromatic compound in the presence of sulfur and sodium carbonate, (2) a dihalogen compound A method of polymerizing aromatic compounds in a polar solvent in the presence of a sulfidizing agent, (3) a method of self-condensing p-chlorothiophenol, and (4) a method of mixing and heating an organic polar solvent and a dihalogeno aromatic compound. The dihalogeno-aromatic compound is reacted with the sulfidizing agent by adding a hydrous sulfidizing agent therein. At this time, the water content of the reaction mixture is 2 to 50 mol% of the organic polar solvent. (JP-A-07-228699).
[0014]
Among these, the production method (4) is preferable because it is easy to obtain a PPS resin having a large molecular weight, and thus the tensile elongation of the resin composition tends to be 25 to 300%.
[0015]
The molecular weight of the PAS resin (A) used in the present invention can be determined by gel permeation chromatography using 1-chloronaphthalene as a solvent. The PAS resin (A) has a peak molecular weight of preferably 35,000 or more because the impact resistance and toughness at low temperatures are remarkably improved, and further has a peak molecular weight of 200,000 or less because of good fluidity during molding. It is preferable, and especially, 40,000 to 100,000 is particularly preferable.
[0016]
The molecular weight of the PAS resin (A) generally has a very large molecular weight distribution, and the tailing of the peak molecular weight on the right and left tends to fluctuate greatly under manufacturing conditions. Therefore, the difference between the number-average molecular weight and the weight-average molecular weight is so large that either of them may not represent the actual situation, and the peak molecular weight indicating the molecular weight where the largest number of molecules are gathered in the molecular weight distribution is relatively high. Was determined to be reflected directly in the sample, and the evaluation was made based on the peak molecular weight. The method for measuring the peak molecular weight will be described in detail in Examples.
[0017]
The higher the molecular weight of the PAS resin (A), the easier the uniform mixing with the thermoplastic elastomer (B) described later. This uniform dispersibility is indispensable for improvement of impact resistance and toughness, and is a more preferable direction.
[0018]
It is preferable that the thermoplastic elastomer (B) used in the present invention can be melted and mixed and dispersed at a temperature at which the PAS resin (A) is kneaded. From that point, an elastomer having a melting point of 300 ° C. or less and having rubber elasticity at room temperature is preferable. In addition, polyolefin-based elastomers or nitrile-based elastomers are preferable from the viewpoint of improving heat resistance, ease of mixing, and impact resistance.
[0019]
As the polyolefin-based elastomer, those having a functional group such as a hydroxyl group, a carboxyl group, an amino group, a mercapto group, an epoxy group, an acid anhydride group, an isocyanate group, an ester group, and a vinyl group are preferable.
[0020]
Further, among these, a functional group or an epoxy group derived from a carboxylic acid such as an acid anhydride, an acid, or an ester is particularly preferable.
[0021]
The polyolefin-based elastomer can be obtained, for example, by copolymerizing an α-olefin and a vinyl polymerizable compound having the functional group. Examples of the α-olefins include α-olefins having 2 to 8 carbon atoms, such as ethylene, propylene, and butene. Examples of the vinyl polymerizable compounds having a functional group include, for example, acrylic acid, methacrylic acid, acrylic acid ester, α, β-unsaturated carboxylic acids such as methacrylic acid esters, and alkyl esters thereof, maleic acid, Α, β-unsaturated dicarboxylic acids and their anhydrides such as fumaric acid, itaconic acid, other unsaturated dicarboxylic acids having 4 to 10 carbon atoms and their mono- and diesters, and their anhydrides; glycidyl (meth) acrylate; Is mentioned.
[0022]
A copolymer containing a plurality of these functional groups at the same time can be used. Preferred examples thereof include terpolymers of α-olefins, maleic anhydride, and glycidyl acrylate.
[0023]
There is the nitrile elastomer. It can be obtained by copolymerizing a nitrile having an unsaturated bond such as acrylonitrile or methacrylonitrile with butadiene or methylbutadiene having a conjugated double bond. This copolymer is more preferably of the type in which part or all of the double bonds are hydrogenated to increase the heat resistance.
[0024]
The thermoplastic elastomer (B) containing these functional groups has a good dispersibility with the PAS resin (A), makes it easier to obtain a uniformly mixed resin composition, and has a low temperature rupture resistance and the like. improves.
[0025]
The mixing ratio of the PAS resin (A) and the thermoplastic elastomer (B) is (A) / (B) = 50/50 to 99/1 (weight ratio), and the tensile elongation of the composition is It is preferable because it falls within the range of 25 to 300%, and 80/20 to 97/3 is particularly preferable.
[0026]
In the resin composition used in the present invention, additives such as various reinforcing materials, fillers, lubricants, and stabilizers can be added and used within a range where the tensile elongation of the resin composition is 25 to 300%. The amount of these additives is not particularly limited, but is preferably 5 parts by weight or less per 100 parts by weight of the composition.
[0027]
The resin composition used in the present invention can be prepared, for example, by the following method.
The PAS resin (A) and the thermoplastic elastomer (B) are mixed in advance by a mixer such as a Henschel mixer or a tumbler, and inserted into a single-screw or twin-screw extruder and kneaded at 200 to 350 ° C. Then, granulate and pelletize to prepare. The method for preparing the resin composition is not particularly limited, and there is no limitation on the timing of addition of the materials, the order, the type and size of the mixer and the extruder.
[0028]
The member for fluid piping of the present invention is obtained by molding the resin composition. Examples of these fluid piping members include pipes, lining pipes, cap nuts, pipe joints (elbows, headers, cheeses, reducers, joints, couplers, etc.), various valves, flow meters, gaskets (seal, packings), And various parts attached to the piping for transporting the fluid.
[0029]
Further, the fluid pipe member of the present invention can be used by being molded alone with the resin composition, but can be combined with other materials, or can be simultaneously molded such as co-extrusion, or can be bonded, caulked, etc. , Can be used together with or as a part of other materials, and the form of use is not limited.
[0030]
The evaluation of the rupture resistance of the pipe member at the time of low-temperature freezing, which is the subject of the present invention, is performed by freezing the internal water at −20 ° C. and checking for the presence or absence of breakage. The specific method is described in Examples. The tensile elongation, which greatly affects the performance, was measured and evaluated according to ASTM D-638.
[0031]
Hereinafter, the present invention will be described with reference to Examples and Comparative Examples.
[0032]
<Measurement method and evaluation method>
1. Measurement of peak molecular weight The PPS resin to be measured was measured by gel permeation chromatography.
Apparatus: Ultra high temperature polymer molecular weight distribution measuring apparatus (SSC-7000 manufactured by Senshu Kagaku)
Column: UT-805L (manufactured by Showa Denko KK)
Column temperature; 210 ° C
Solvent: 1-chloronaphthalene UV detector (360 nm) was used to calibrate six types of monodisperse polystyrene for calibration, and the molecular weight distribution and peak molecular weight were measured.
[0033]
2. Measurement of Tensile Property-Elongation Rate A test piece of the resin composition to be measured was prepared in ASTM No. 4 dumbbell shape, and measured according to ASTM D638 by "Autograph AG-5000C" manufactured by Shimadzu Corporation, and the tensile strength and tensile elongation at break were measured. It was measured.
[0034]
3. Filling Water Freezing Test-Measurement of Low Temperature Rupture Resistance A cylindrical pipe joint having an inner diameter of 22 mm and an outer diameter of 28 mm that can be hermetically sealed with a flange and a screw structure at both ends was formed by injection molding from the resin composition to be evaluated.
Fill with water in water so as not to contain an air layer, close both ends, take out of the water, put in a freezer at -20 ° C, leave for 2 hours, and completely freeze the water inside. Was. Thereafter, the tube was taken out of the freezer and examined for cracks in the pipe joint to evaluate low-temperature rupture resistance.
4. Measurement of Mooney viscosity Measured according to JIS K-6300.
Measurement conditions: Rotor L-type preliminary 1 minute, operation 4 minutes, 100 ° C
5. Measurement of MFR Measured according to JIS K-6700.
[0035]
Synthesis Example 1
[Preparation of hydrous sulfidizing agent]
The following materials were mixed to prepare a hydrous sulfidizing agent.
(1) Hydrous flake sodium sulfide (Nagao); 1.5 kg [purity / Na ₂ S (58.9% by weight), NaSH (1.3% by weight)]
(2) Hydrous flake sodium bisulfide (manufactured by Nagao); 0.225 kg [purity / NaSH (71.2% by weight), Na2S (2.7% by weight)]
(3) Water; 0.425 kg
The above three types were mixed to prepare 2.15 kg of a hydrous sulfidizing agent.
[0036]
[Synthesis of PPS resin]
Paradichlorobenzene (1.838 kg), N-methyl-2-pyrrolidone (4.958 kg), water (0.09 kg) were placed in a reaction tank equipped with a temperature sensor, a cooler, a dropping tank, a distillate separation tank, and a stirring blade. And heated to 100 ° C. while stirring under a nitrogen atmosphere. After sealing the reaction tank, the above-mentioned hydrosulfide agent (2.15 kg) was added dropwise at 220 ° C. and an internal pressure of 0.22 MPa. Dehydration is performed during the dropping reaction, paradichlorobenzene co-emitted is returned to the reaction tank, and water is discharged out of the system, whereby the amount of water in the system is 0.02 to 0. 0 to 1 mol of N-methyl-2-pyrrolidone. The reaction was adjusted to 5 mol. The reaction was carried out by raising the temperature until the temperature reached 240 ° C., and then kept at 240 ° C. for 1 hour to terminate the reaction. At the end of the reaction, it was confirmed that water was 0.17 mol% of the polar solvent (N-methyl-2-pyrrolidone). During the reaction and at the end of the reaction, it was confirmed that water was in the range of 0.02 to 0.5 mol per mol of the polar solvent. The obtained reaction product was washed with water and dried to obtain a white powdery polymer. This polymer is referred to as “PPS-1”. PPS-1 had a peak molecular weight of 40,700.
[0037]
Examples 1 to 5 and Comparative Example 1
The resin compound pellets were obtained by uniformly mixing the materials in Table 1, kneading at 290 to 330 ° C. using a 35 mmφ twin screw extruder, and then pelletizing. Then, the pellets are subjected to a tensile test specimen and a pipe joint for evaluating low-temperature fracture resistance at an in-line screw type injection molding machine at a cylinder temperature of 290 to 320 ° C, a mold temperature of 130 ° C, and an injection pressure of 80 to 100 MPa. Was molded. Next, the low-temperature rupture resistance was evaluated by the above-described evaluation method. Table 1 shows the obtained results.
[0038]
[Table 1]

[0039]
The following components were used for each component in the table.
PPS-2; PPS (peak molecular weight 34,200 [manufactured by Dainippon Ink and Chemicals, Inc. (LR-2G)])
PPS-3; PPS (peak molecular weight 16,000 [manufactured by Dainippon Ink and Chemicals, Inc. (B-100-C)])
ELA-1: a polyolefin elastomer comprising glycidyl methacrylate (3% by weight), methyl acrylate (30% by weight), and ethylene (67% by weight). MFR = 9
ELA-2: a thermoplastic elastomer; a polyolefin-based elastomer comprising maleic anhydride (2% by weight), ethyl acrylate (31% by weight), and ethylene (67% by weight). MFR = 7
ELA-3: A hydrogenated acrylonitrile-butadiene copolymer comprising an acrylonitrile content (36% by weight) and a carboxyl group-containing monomer (5% by weight) having an iodine value of 4 g / 100 g. Moonlight viscosity = 85 (manufactured by Zeon Corporation)
[0040]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the member for piping which has favorable low temperature rupture resistance outdoors at very low temperature can be provided.

Claims (5)

A fluid piping member comprising a resin composition containing a polyarylene sulfide resin (A) and a thermoplastic elastomer (B), wherein the resin composition has a tensile elongation at 25 ° C of 25 to 300%. A member for a fluid pipe, characterized by being provided. The member for fluid piping according to claim 1, wherein the thermoplastic elastomer (B) is a polyolefin-based elastomer or a nitrile-based elastomer. The fluid piping member according to claim 1 or 2, wherein the polyarylene sulfide resin (A) has a peak molecular weight of a molecular weight distribution determined by gel permeation chromatography of 35,000 to 200,000. While heating the mixture containing the organic polar solvent and the dihalogen aromatic compound, the polyarylene sulfide resin (A) adjusts the water content in the reaction system to 0.02 to 0.5 mol per 1 mol of the organic polar solvent. The fluid according to claim 1, which is obtained by supplying a hydrous sulfidizing agent while controlling to within the range described above, and reacting the dihalogen aromatic compound with the sulfidizing agent in the organic polar solvent. Piping member. The fluid pipe member according to any one of claims 1 to 4, which is a joint member.