JP2004091288A - Cement premix product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cement premix product in which a material containing a water soluble vinyl copolymer is blended as the powdery dispersant and the quantity of entrained air is controlled to be sufficiently low even when a powdery defoaming agent stored over days is blended in the cement premix product. <P>SOLUTION: A material containing a specific block copolymer, porous silica fine powder and an antioxidant in a prescribed ratio is used as the powdery defoaming agent. <P>COPYRIGHT: (C)2004,JPO

Description

【０００７】
式１において、
Ｒ^１：炭素数１２〜２２の脂肪族炭化水素基
Ａ^１：オキシエチレン単位の繰り返し数２〜１５のポリエチレングリコールから全ての水酸基を除いた残基
Ａ^２：オキシプロピレン単位の繰り返し数１０〜７０のポリプロピレングリコールから全ての水酸基を除いた残基
【０００８】
Ｂ成分：多孔質シリカ微粉末
Ｃ成分：酸化防止剤
【０００９】
本発明のセメントプレミックス製品は、少なくともセメント、水溶性ビニル共重合体を含有する粉末状分散剤及び特定の粉末状消泡剤を配合して成るものである。セメント及び水溶性ビニル共重合体を含有する粉末状分散剤それ自体は公知のものを用いることもできるので、これらについては後述することとし、ここでは先ず、特定の粉末状消泡剤について説明する。
【００１０】
本発明のセメントプレミックス製品に用いる粉末状消泡剤は、前記のＡ成分、Ｂ成分及びＣ成分からなるものである。粉末状消泡剤のＡ成分は、式１で示されるブロック共重合体である。かかるブロック共重合体は、脂肪族炭化水素基とポリオキシエチレン基とがエーテル結合で連結しており、該ポリオキシエチレン基にポリオキシプロピレン基がエーテル結合で連結していて、該ポリオキシプロピレン基の片末端に水酸基が結合した構造のものである。かかる構造のブロック共重合体は、例えば脂肪族アルコールにエチレンオキサイドを付加重合した後、更にプロピレンオキサイドを付加重合して得られる。
【００１１】
粉末状消泡剤のＡ成分において、式１中のＲ^１としては、１）ドデシル基、トリデシル基、テトラデシル基、ペンタデシル基、ヘキサデシル基、ヘプタデシル基、オクタデシル基、ノナデシル基、エイコシル基、ヘンエイコシル基、ドコシル基、イソトリデシル基、５−メチル−４−プロピルノニル基、２，７，８−トリメチルデシル基等の炭素数１２〜２２の飽和脂肪族炭化水素基、２）８−ヘキサデセニル基、９−オクタデセニル基、１０−エイコセニル基等の炭素数１２〜２２の不飽和脂肪族炭化水素基等が挙げられるが、なかでも不飽和脂肪族炭化水素基が好ましく、９−オクタデセニル基がより好ましい。
【００１２】
粉末状消泡剤のＡ成分において、式１中のＡ^１はオキシエチレン単位の繰り返し数２〜１５のポリエチレングリコールから全ての水酸基を除いた残基であるが、Ａ^１としてはオキシエチレン単位の繰り返し数４〜１０のポリエチレングリコールから全ての水酸基を除いた残基が好ましい。
【００１３】
粉末状消泡剤のＡ成分において、式１中のＡ^２はオキシプロピレン単位の繰り返し数１０〜７０のポリプロピレングリコールから全ての水酸基を除いた残基であるが、Ａ^２としてはオキシプロピレン単位の繰り返し数２０〜５０のポリプロピレングリコールから全ての水酸基を除いた残基が好ましい。
【００１４】
粉末状消泡剤のＡ成分としての式１で示されるブロック共重合体は、公知の方法で合成できる。例えば、脂肪族アルコールに、アルカリ触媒を用いた加温及び加圧下で、エチレンオキサイドを付加重合反応させた後、プロピレンオキサイドを付加重合反応させる方法で合成できる。
【００１５】
粉末状消泡剤のＢ成分は多孔質シリカ微粉末である。かかる多孔質シリカ微粉末としては、公知のものを利用できるが、なかでも比表面積が５０〜４５０ｍ^２／ｇであって、且つ平均粒径が０．１〜５００μｍの範囲のものが好ましく、更に平均粒径が１〜９９μｍのものがより好ましい。特に吸油量（ＪＩＳ−Ｋ５１０１−１９による吸油量）が１００ｍ^２／ｇを越えるものが好ましい。
【００１６】
粉末状消泡剤のＣ成分は酸化防止剤である。かかる酸化防止剤としては、公知のものを利用でき、これには例えばハイドロキノン、ハイドロキノンモノメチルエーテル、フェノチアジン、ジブチルヒドロキシトルエン、ブチルヒドロキシアニソール、亜リン酸トリブチル、亜リン酸トリフェニル等が挙げられるが、なかでもハイドロキノン、ジブチルヒドロキシトルエン、ブチルヒドロキシアニソールが好ましい。これらの酸化防止剤は一つ又は二つ以上を用いることができる。
【００１７】
本発明のセメントプレミックス製品に用いる粉末状消泡剤は、以上説明したようなＡ成分を１５〜７４重量％、Ｂ成分を２５〜８４重量％及びＣ成分を０．００１〜１重量％（合計１００重量％）含有してなるものであるが、Ａ成分を３０〜６９．５重量％、Ｂ成分を３０〜６９．５重量％、Ｃ成分を０．０５〜０．５重量％（合計１００重量％）含有してなるものが好ましい。
【００１８】
本発明のセメントプレミックス製品に用いる粉末状消泡剤は、例えば、攪拌羽根を備えたミキサーに、Ａ成分、Ｂ成分及びＣ成分が所定割合となるよう、先ずＢ成分を投入し、次に予めＡ成分とＣ成分とを混合しておいた混合物を攪拌しながら少しずつ投入して均一混合することにより製造できる。ここで得られた製造物は通常粒径が３０００μｍ以下の粉末状となるが、かかる粉末状消泡剤を本発明のセメントプレミックス製品に用いる場合には、その粒径を揃えたものとするのが好ましく、粒径が１〜２０００μｍで、且つ平均粒径が１〜１５００μｍとなるよう篩を用いて分級したものが好ましい。
【００１９】
本発明のセメントプレミックス製品に用いる粉末状分散剤は水溶性ビニル共重合体を含有するものである。かかる粉末状分散剤としては、公知のものも利用できるが、下記のＤ成分とＥ成分との水系混合物を乾燥し、粉砕したものが好ましい。
【００２０】
Ｄ成分：１）全構成単位中に、下記の式２で示されるビニル単量体から形成された構成単位Ａを４０〜８０モル％、下記の式３で示されるビニル単量体から形成された構成単位Ｂを１〜２５モル％、下記の式４で示されるビニル単量体から形成された構成単位Ｃを３〜２０モル％及び下記の式５で示されるビニル単量体から形成された構成単位Ｄを１〜４５モル％（合計１００モル％）有する数平均分子量２０００〜７００００の水溶性ビニル共重合体、２）全構成単位中に、下記の式２で示されるビニル単量体から形成された構成単位Ａを４０〜７０モル％、下記の式３で示されるビニル単量体から形成された構成単位Ｂを５〜３０モル％、下記の式４で示されるビニル単量体から形成された構成単位Ｃを１〜２０モル％、下記の式５で示されるビニル単量体から形成された構成単位Ｄを１〜３０モル％及び下記の式６で示されるビニル単量体から形成された構成単位Ｅを１〜３０モル％（合計１００モル％）有する数平均分子量２０００〜７００００の水溶性ビニル共重合体、以上の１）及び２）から選ばれる一つ又は二つ以上
【００２１】
Ｅ成分：亜硫酸アルカリ金属塩、亜硫酸アルカリ土類金属塩、チオ硫酸アルカリ金属塩、チオ硫酸アルカリ土類金属塩、アルカリ土類金属の水酸化物、硝酸アルカリ土類金属塩、硝酸金属塩、亜硝酸アルカリ土類金属塩及び亜硝酸金属塩から選ばれる一つ又は二つ以上
【００２２】
【式２】

【００２３】
【式３】

【００２４】
【式４】

【００２５】
【式５】

【００２６】
【式６】

【００２７】
式２〜式６において、
Ｒ^２，Ｒ^３，Ｒ^４，Ｒ^５，Ｒ^７：水素原子又はメチル基
Ｒ^６，Ｒ^８：炭素数１〜３のアルキル基
Ｍ^１：水素原子、アルカリ金属、アルカリ土類金属、アンモニウム又は有機アミン
Ｚ：−ＳＯ_３Ｍ^２又は−Ｏ−Ｃ_６Ｈ_４−ＳＯ_３Ｍ^３で示される有機基
（Ｍ^２，Ｍ^３；アルカリ金属、アルカリ土類金属、アンモニウム又は有機アミン）
Ａ^３：オキシエチレン単位のみ又はオキシエチレン単位とオキシプロピレン単位との双方からなるオキシアルキレン単位の繰り返し数が５〜１０９のポリアルキレングリコールから全ての水酸基を除いた残基
Ａ^４：オキシエチレン単位のみ又はオキシエチレン単位とオキシプロピレン単位との双方からなるオキシアルキレン単位の繰り返し数が５〜５０のポリアルキレングリコールから全ての水酸基を除いた残基
【００２８】
粉末状分散剤のＤ成分には、１）式２で示されるビニル単量体から形成された構成単位Ａ、式３で示されるビニル単量体から形成された構成単位Ｂ、式４で示されるビニル単量体から形成された構成単位Ｃ及び式５で示されるビニル単量体から形成された構成単位Ｄをそれぞれ所定割合で有する水溶性ビニル共重合体、２）式２で示されるビニル単量体から形成された構成単位Ａ、式３で示されるビニル単量体から形成された構成単位Ｂ、式４で示されるビニル単量体から形成された構成単位Ｃ、式５で示されるビニル単量体から形成された構成単位Ｄ及び式６で示されるビニル単量体から形成された構成単位Ｅをそれぞれ所定割合で有する水溶性ビニル共重合体、３）前記１）及び２）の混合物が包含される。かかる水溶性ビニル共重合体は、それぞれ構成単位Ａ〜Ｄ又は構成単位Ａ〜Ｅを形成することとなるビニル単量体をラジカル共重合することにより得られる。
【００２９】
構成単位Ａを形成することとなる式２で示されるビニル単量体としては、１）メタクリル酸、アクリル酸、２）メタクリル酸のアルカリ金属塩、アルカリ土類金属塩又は有機アミン塩、３）アクリル酸のアルカリ金属塩、アルカリ土類金属塩又は有機アミン塩等がある。なかでもメタクリル酸のナトリウムやカリウム等のアルカリ金属塩が好ましい。
【００３０】
構成単位Ｂを形成することとなる式３で示されるビニル単量体としては、１）（メタ）アリルスルホン酸のアルカリ金属塩、アルカリ土類金属塩又は有機アミン塩、２）ｐ−メタリルオキシベンゼンスルホン酸のアルカリ金属塩、アルカリ土類金属塩又は有機アミン塩等がある。なかでもメタリルスルホン酸のナトリウムやカリウム等のアルカリ金属塩が好ましい。
【００３１】
構成単位Ｃを形成することとなる式４で示されるビニル単量体としては、メチルアクリレート、メチルメタクリレートがある。
【００３２】
構成単位Ｄを形成することとなる式５で示されるビニル単量体としては、１）オキシエチレン単位の繰り返し数が５〜１０９である、炭素数１〜３のアルキル基を有するアルコキシポリエチレングリコール（メタ）アクリレート、２）オキシエチレン単位の繰り返し数とオキシプロピレン単位の繰り返し数の合計が５〜１０９である、炭素数１〜３のアルキル基を有するアルコキシポリアルキレングリコール（メタ）アクリレート、３）前記１）及び前記２）の混合物が挙げられる。これには例えば、メトキシポリエトキシエチル（メタ）アクリレート、エトキシポリエトキシエチル（メタ）アクリレート、ｎ−プロポキシポリエトキシエチル（メタ）アクリレート、イソプロポキシポリエトキシエチル（メタ）アクリレート等が挙げられるが、なかでもオキシエチレン単位の繰り返し数が７〜１００であるメトキシポリエトキシエチルメタクレートが好ましい。
【００３３】
構成単位Ｅを形成することとなる式６で示されるビニル単量体としては、１）オキシエチレン単位の繰り返し数が５〜５０である、炭素数１〜３のアルキル基を有するアルコキシポリエチレングリコール（メタ）アリルエーテル、２）オキシエチレン単位の繰り返し数とオキシプロピレン単位の繰り返し数の合計が５〜５０である、炭素数１〜３のアルキル基を有するアルコキシポリアルキレングリコール（メタ）アリルエーテル、３）前記１）及び前記２）の混合物が挙げられる。なかでもオキシエチレン単位の繰り返し数が７〜３５であるメトキシポリエチレングリコ―ルメタリルエーテルが好ましい。
【００３４】
粉末状分散剤に供する前記のような水溶性ビニル共重合体は、ラジカル開始剤の存在下に、構成単位Ａ〜Ｄ又は構成単位Ａ〜Ｅを形成することとなる前記したようなビニル単量体を所定の共重合比率となるようラジカル共重合することにより得られる。かかるラジカル共重合は通常、水を溶媒に用いた水溶液重合により行なう。より具体的には、先ず各ビニル単量体を水に溶解し、各ビニル単量体を合計量として１０〜４５重量％含む水溶液を調製する。次に窒素ガス雰囲気下において、調製した水溶液にラジカル開始剤を加え、５０〜７０℃で５〜８時間ラジカル共重合反応させて水溶性ビニル共重合体を得る。用いるラジカル開始剤としては、共重合反応温度下において分解し、ラジカル発生するものであればその種類は特に制限されないが、水溶性のラジカル開始剤を用いるのが好ましい。かかる水溶性のラジカル開始剤としては、過硫酸ナトリウム、過硫酸カリウム、過硫酸アンモニウム等の過硫酸塩等が挙げられる。
【００３５】
かくして得られる水溶性ビニル共重合体は、それが構成単位Ａ〜Ｄからなるものの場合、その全構成単位中に、構成単位Ａを４０〜８０モル％、好ましくは５５〜７２モル％、構成単位Ｂを１〜２５モル％、好ましくは３〜１８モル％、構成単位Ｃを３〜２０モル％、好ましくは４〜１５モル％及び構成単位Ｄを１〜４５モル％、好ましくは３〜２５モル％（合計１００モル％）有するものとする。またそれが構成単位Ａ〜Ｅからなるものの場合、その全構成単位中に、構成単位Ａを４０〜７０モル％、好ましくは５５〜６８モル％、構成単位Ｂを５〜３０モル％、好ましくは６〜１８モル％、構成単位Ｃを１〜２０モル％、好ましくは３〜１５モル％、構成単位Ｄを１〜３０モル％、好ましくは３〜１５モル％及び構成単位Ｅを１〜３０モル％、好ましくは２〜２５モル％（合計１００モル％）有するものとする。またその数平均分子量はいずれも２０００〜７００００（ＧＰＣ法、プルラン換算、以下同じ）の範囲内のものとするが、好ましくは３０００〜４５０００の範囲内のものとする。
【００３６】
セメント分散剤に供するＥ成分には、１）亜硫酸カリウム、亜硫酸ナトリウム等の亜硫酸アルカリ金属塩、２）亜硫酸カルシウム、亜硫酸マグネシウム等の亜硫酸アルカリ土類金属塩、３）チオ硫酸カリウム、チオ硫酸ナトリウム等のチオ硫酸アルカリ金属塩、４）チオ硫酸カルシウム、チオ硫酸マグネシウム等のチオ硫酸アルカリ土類金属塩、５）水酸化カルシウム（消石灰）、水酸化バリウム、水酸化ストロンチウム等のアルカリ土類金属の水酸化物、６）硝酸カルシウム、硝酸マグネシウム等の硝酸アルカリ土類金属塩、７）硝酸鉄、硝酸銅等の硝酸金属塩、８）亜硝酸カルシウム、亜硝酸マグネシウム等の亜硝酸アルカリ土類金属塩、９）亜硝酸鉄、亜硝酸銅等の亜硝酸金属塩、１０）前記１）〜９）から選ばれる二つ以上の混合物が挙げられるが、なかでも水酸化カルシウム（消石灰）、硝酸カルシウム、亜硝酸カルシウム、亜硫酸ナトリウム、チオ硫酸ナトリウムが好ましい。
【００３７】
本発明のセメントプレミックス製品に好ましいものとして用いる粉末状分散剤は、Ｄ成分としての前記した水溶性ビニル共重合体とＥ成分としての前記した無機化合物との水系混合物を乾燥し、粉砕したものである。
【００３８】
この場合の水系混合物とは、Ｄ成分としての水溶性ビニル共重合体とＥ成分としての無機化合物とを、水を主とする系、通常は水溶液の系で混合したものを意味する。したがって、Ｄ成分としての水溶性ビニル共重合体を前記した水溶液重合によりその水溶液として得る場合には、これをそのまま用いて、Ｅ成分としての無機化合物と混合することができる。
【００３９】
Ｄ成分とＥ成分とは、１）Ｅ成分が亜硫酸アルカリ金属塩、亜硫酸アルカリ土類金属塩、チオ硫酸アルカリ金属塩又はチオ硫酸アルカリ土類金属塩の場合、Ｄ成分／Ｅ成分＝９９．９９／０．０１〜９７／３（重量比）の割合となるよう水系混合するのが好ましく、Ｄ成分／Ｅ成分＝９９．５／０．５〜９７．５／２．５（重量比）の割合となるよう水系混合するのがより好ましい。また２）Ｅ成分がアルカリ土類金属の水酸化物、硝酸アルカリ土類金属塩、硝酸金属塩、亜硝酸アルカリ土類金属塩又は亜硝酸金属塩の場合、Ｄ成分／Ｅ成分＝１０／９０〜９０／１０（重量比）の割合となるよう水系混合するのが好ましく、Ｄ成分／Ｅ成分＝２５／７５〜７５／２５（重量比）の割合となるよう水系混合するのがより好ましい。
【００４０】
Ｄ成分とＥ成分との水系混合物を乾燥し、粉砕する手段には、１）双方を水系混合し、次いで乾燥した後、粉砕する場合、２）双方を水系混合しつつ乾燥した後、粉砕する場合、３）双方を水系混合した後、乾燥しつつ粉砕する場合、４）双方の水系混合、乾燥及び粉砕を並行して行なう場合がある。より具体的には例えば、Ｄ成分としての水溶性ビニル共重合体の水溶液とＥ成分としての無機化合物との混合物の固形分濃度が５〜４０重量％となる場合には、水溶性ビニル共重合体の水溶液に無機化合物を加え、６０〜１００℃の温度で混合し、次いでスプレードライヤーやフラッシュジェットドライヤー等を用いて乾燥した後、粉砕して粉末状分散剤を得る。また例えば、Ｄ成分としての水溶性ビニル共重合体の水溶液とＥ成分としての無機化合物との混合物の固形分濃度が４０重量％を超えることとなる場合には、水溶性ビニル共重合体の水溶液に無機化合物を加え、６０〜１２０℃の温度で撹拌混練型乾燥機やバンド型連続真空乾燥機を用いて混合しつつ乾燥した後、粉砕して粉末状分散剤を得る。
【００４１】
かくして得られる粉末状分散剤は、これをそのまま本発明のセメントプレミックス製品の製造に使用することもできるが、これを用いてセメントプレミックス製品を製造する際の利便性から、更に分級して、その粒径を揃えたものとするのが好ましい。この場合の分級は、粉砕しつつ分級してもよいし、或は粉砕した後に分級してもよい。Ｄ成分とＥ成分との水系混合物を乾燥し、粉砕する場合も、また更に分級する場合も、得られる粉末状分散剤の上記のような利便性から、その粒径が３０００μｍ以下で且つ平均粒径が５〜２０００μｍのものとするのが好ましく、その粒径が７００μｍ以下で且つ平均粒径が５〜５００μｍのものとするのがより好ましい。
【００４２】
本発明のセメントプレミックス製品において、セメントとしては、普通ポルトランドセメント、早強ポルトランドセメント、中庸熱ポルトランドセメント、高ビーライトポルトランドセメント等の各種ポルトランドセメントの他に、高炉セメント、フライアッシュセメント、シリカフュームセメント等の各種混合セメントやアルミナセメントを使用できるが、中でも施工時間の短縮を必要とする場面では、早強性のアルミナセメントや早強ポルトランドセメントが好ましい。
【００４３】
本発明のセメントプレミックス製品は、以上説明したような少なくともセメント、粉末状分散剤及び粉末状消泡剤を配合したものであるが、かかるセメントプレミックス製品としては、１）セメント、粉末状分散剤及び粉末状消泡剤を配合したセメントプレミックス製品、２）セメント、細骨材、粉末状分散剤及び粉末状消泡剤を配合したセメントプレミックス製品が挙げられる。
【００４４】
本発明のセメントプレミックス製品において、セメントに対する粉末状分散剤及び粉末状消泡剤の配合割合は、セメント１００重量部当たり、粉末状分散剤を０．１〜５重量部、また粉末状消泡剤を０．０００５〜０．０２重量部となるようにするのが好ましい。
【００４５】
なかでも、本発明のセメントプレミックス製品が細骨材を配合しないものの場合には、セメント１００重量部当たり、粉末状分散剤を０．２〜１重量部、また粉末状消泡剤を０．００１〜０．０１重量部となるようにするのがより好ましく、また本発明のセメントプレミックス製品が細骨材を配合したものの場合には、セメントと細骨材との合計量１００重量部当たり、粉末状分散剤を０．１〜０．５重量部、また粉末状消泡剤を０．０００５〜０．００５重量部となるようにするのがより好ましい。本発明のセメントプレミックス製品が細骨材を配合したものの場合、セメントと細骨材との割合は、セメント／細骨材＝２０／８０〜７０／３０（重量比）とするのが好ましく、３０／７０〜６０／４０（重量比）とするのがより好ましい。
【００４６】
本発明のセメントプレミックス製品には、合目的的に通常セメントプレミックス製品に用いられる添加剤を併用することができる。かかる添加剤としては防水剤、硬化促進剤、硬化遅延剤等が挙げられる。
【００４７】
【発明の実施の形態】
本発明のセメントプレミックス製品の実施形態としては、次の１）〜１６）が挙げられる。
１）セメント１００重量部、下記の粉末状分散剤（Ｐ−１）０．４重量部及び下記の粉末状消泡剤（Ｍ−１）０．００２重量部を配合したセメントプレミックス製品。
粉末状分散剤（Ｐ−１）：Ｄ成分として全構成単位中にメタクリル酸ナトリウムから形成された構成単位を６２モル％、メタリルスルホン酸ナトリウムから形成された構成単位を１２モル％、メチルアクリレートから形成された構成単位を１２モル％、メトキシポリエトキシエチル（エトキシ単位の繰り返し数６８、以下単に６８とする）メタクリレートから形成された構成単位を８モル％及びメトキシポリエトキシエチル（９）メタクリレートから形成された構成単位を６モル％（合計１００モル％）有する数平均分子量１４６００の水溶性ビニル共重合体（Ｄ−１）／Ｅ成分として亜硫酸ナトリウム塩（Ｅ−１）＝９９．５／０．５（重量比）の割合で含有する水系混合物を乾燥し、粉砕して、分級した粒径７００μｍ未満で、且つ平均粒径４５０μｍの粉末状分散剤
粉末状消泡剤（Ｍ−１）：下記のＡ成分を６０重量％、下記のＢ成分を３９．８重量％及び下記のＣ成分を０．２重量％（合計１００重量％）の割合で混合し、分級した粒径１〜５００μｍで、且つ平均粒径１６０μｍの粉末状消泡剤。
Ａ成分：式１中のＲ^１が９−オクタデセニル基、Ａ^１がオキシエチレン単位の繰り返し数６のポリエチレングリコールから全ての水酸基を除いた残基、Ａ^２がオキシプロピレン単位の繰り返し数４０のポリプロピレングリコールから全ての水酸基を除いた残基である場合の式１で示されるブロック共重合体（Ａ−１）
Ｂ成分：比表面積１６０ｍ^２／ｇで、且つ平均粒径８０μｍの多孔質シリカ微粉末（Ｂ−１）
Ｃ成分：ハイドロキノン（Ｃ−１）
【００４８】
２）セメント１００重量部、下記の粉末状分散剤（Ｐ−２）０．４重量部及び前記の粉末状消泡剤（Ｍ−１）０．００５重量部を配合したセメントプレミックス製品。
粉末状分散剤（Ｐ−２）：Ｄ成分として全構成単位中にメタクリル酸ナトリウムから形成された構成単位を５８モル％、ｐ−メタリルオキシベンゼンスルホン酸ナトリウムから形成された構成単位を１８モル％、メチルアクリレートから形成された構成単位を８モル％、メトキシポリエトキシエチル（９５）メタクリレートから形成された構成単位を１０モル％及びメトキシポリエトキシエチル（２３）メタクリレートから形成された構成単位を６モル％（合計１００モル％）有する数平均分子量９２００の水溶性ビニル共重合体（Ｄ−２）／Ｅ成分としてチオ硫酸ナトリウム塩（Ｅ−２）＝９８．５／１．５（重量比）の割合で含有する水系混合物を乾燥し、粉砕して、分級した粒径７００μｍ未満で、且つ平均粒径４９０μｍの粉末状分散剤
【００４９】
３）セメント１００重量部、下記の粉末状分散剤（Ｐ−３）０．６重量部及び下記の粉末状消泡剤（Ｍ−２）０．００３重量部を配合したセメントプレミックス製品。
粉末状分散剤（Ｐ−３）：Ｄ成分として全構成単位中にメタクリル酸ナトリウムから形成された構成単位を６２モル％、メタリルスルホン酸ナトリウムから形成された構成単位を８モル％、ｐ−メタリルオキシベンゼンスルホン酸ナトリウムから形成された構成単位を５モル％、メチルアクリレートから形成された構成単位を２モル％、メトキシポリエトキシエチル（２３）メタクリレートから形成された構成単位を１０モル％及びメトキシポリエチレングリコール（２４）アリルエーテルから形成された構成単位を１５モル％（合計１００モル％）有する数平均分子量６２００の水溶性ビニル共重合体（Ｄ−３）／Ｅ成分として消石灰／亜硝酸カルシウム＝６５／３５（重量比）の割合の混合物（Ｅ−３）＝４０／６０（重量比）の割合で含有する水系混合物を乾燥し、粉砕して、分級した粒径７００μｍ未満で、且つ平均粒径３７０μｍの粉末状分散剤
粉末状消泡剤（Ｍ−２）：Ａ成分として前記のブロック共重合体（Ａ−１）を６５重量％、Ｂ成分として前記の多孔質シリカ微粉末（Ｂ−１）を３４．９３重量％及び下記のＣ成分を０．０７重量％（合計１００重量％）の割合で混合し、分級した粒径１〜５００μｍで、且つ平均粒径１８０μｍの粉末状消泡剤
Ｃ成分：ジブチルヒドロキシトルエン（Ｃ−２）
【００５０】
４）セメント１００重量部、下記の粉末状分散剤（Ｐ−４）０．３重量部及び前記の粉末状消泡剤（Ｍ−２）０．００６重量部を配合したセメントプレミックス製品。
粉末状分散剤（Ｐ−４）：Ｄ成分として全構成単位中にメタクリル酸ナトリウムから形成された構成単位を５８モル％、メタリルスルホン酸ナトリウムから形成された構成単位を１７モル％、メチルアクリレートから形成された構成単位を８モル％、メトキシポリエトキシエチル（６８）メタクリレートから形成された構成単位を６モル％及びメトキシポリエチレングリコール（３２）アリルエーテルから形成された構成単位を１０モル％（合計１００モル％）有する数平均分子量１３０００の水溶性ビニル共重合体（Ｄ−４）／Ｅ成分として消石灰／亜硝酸カルシウム／硝酸カルシウム＝２５／４０／３５（重量比）の割合の混合物（Ｅ−４）＝２５／７５（重量比）の割合で含有する水系混合物を乾燥し、粉砕して、分級した粒径７００μｍ未満で、且つ平均粒径４１０μｍの粉末状分散剤
【００５１】
５）セメント１００重量部、前記の粉末状分散剤（Ｐ−１）０．３重量部及び下記の粉末状消泡剤（Ｍ−３）０．００３重量部を配合したセメントプレミックス製品。
粉末状消泡剤（Ｍ−３）：Ａ成分として前記のブロック共重合体（Ａ−１）を４０重量％、Ｂ成分として前記の多孔質シリカ微粉末（Ｂ−１）を５９．６重量％及び下記のＣ成分を０．４重量％（合計１００重量％）の割合で混合し、分級した粒径１〜５００μｍで、且つ平均粒径１４５μｍの粉末状消泡剤
Ｃ成分：ジブチルヒドロキシアニソール（Ｃ−３）
【００５２】
６）セメント１００重量部、前記の粉末状分散剤（Ｐ−２）０．６重量部及び前記の粉末状消泡剤（Ｍ−３）０．００９重量部を配合したセメントプレミックス製品。
【００５３】
７）セメント１００重量部、前記の粉末状分散剤（Ｐ−３）０．４重量部及び下記の粉末状消泡剤（Ｍ−４）０．００３重量部を配合したセメントプレミックス製品。
粉末状消泡剤（Ｍ−４）：下記のＡ成分を６０重量％、下記のＢ成分を３９．８重量％及びＣ成分として前記のハイドロキノン（Ｃ−１）を０．２重量％（合計１００重量％）の割合で混合し、分級した粒径１〜５００μｍで、且つ平均粒径１５５μｍの粉末状消泡剤
Ａ成分：式１中のＲ^１が９−オクタデセニル基、Ａ^１がオキシエチレン単位の繰り返し数８のポリエチレングリコールから全ての水酸基を除いた残基、Ａ^２がオキシプロピレン単位の繰り返し数３０のポリプロピレングリコールから全ての水酸基を除いた残基である場合の式１で示されるブロック共重合体（Ａ−２）
Ｂ成分：比表面積１８０ｍ^２／ｇで、且つ平均粒径８５μｍの多孔質シリカ微粉末（Ｂ−２）
【００５４】
８）セメント１００重量部、前記の粉末状分散剤（Ｐ−４）０．４重量部及び前記の粉末状消泡剤（Ｍ−４）０．００６重量部を配合したセメントプレミックス製品。
【００５５】
９）セメント３３重量部、細骨材６７重量部、前記の粉末状分散剤（Ｐ−１）０．２重量部及び前記の粉末状消泡剤（Ｍ−１）０．００２重量部を配合したセメントプレミックス製品。
【００５６】
１０）セメント３３重量部、細骨材６７重量部、前記の粉末状分散剤（Ｐ−２）０．２重量部及び前記の粉末状消泡剤（Ｍ−１）０．００３重量部を配合したセメントプレミックス製品。
【００５７】
１１）セメント３３重量部、細骨材６７重量部、前記の粉末状分散剤（Ｐ−３）０．３重量部及び前記の粉末状消泡剤（Ｍ−２）０．００２重量部を配合したセメントプレミックス製品
【００５８】
１２）セメント３３重量部、細骨材６７重量部、前記の粉末状分散剤（Ｐ−４）０．３重量部及び前記の粉末状消泡剤（Ｍ−２）０．００３重量部を配合したセメントプレミックス製品。
【００５９】
１３）セメント３３重量部、細骨材６７重量部、前記の粉末状分散剤（Ｐ−１）０．２重量部及び前記の粉末状消泡剤（Ｍ−３）０．００２重量部を配合したセメントプレミックス製品。
【００６０】
１４）セメント３３重量部、細骨材６７重量部、前記の粉末状分散剤（Ｐ−２）０．３重量部及び前記の粉末状消泡剤（Ｍ−３）０．００５重量部を配合したセメントプレミックス製品。
【００６１】
１５）セメント３３重量部、細骨材６７重量部、前記の粉末状分散剤（Ｐ−３）０．２重量部及び前記の粉末状消泡剤（Ｍ−４）０．００２重量部を配合したセメントプレミックス製品。
【００６２】
１６）セメント３３重量部、細骨材６７重量部、前記の粉末状分散剤（Ｐ−４）０．３重量部及び前記の粉末状消泡剤（Ｍ−４）０．００３重量部を配合したセメントプレミックス製品。
【００６３】
以下、本発明の構成及び効果をより具体的にするため、実施例等を挙げるが、本発明がこれらの実施例に限定されるというものではない。尚、以下の実施例及び比較例において、部は重量部を、また％は重量％を意味する。
【００６４】
【実施例】
試験区分１（ブロック共重合体の合成）
・ブロック共重合体（Ａ−１）の合成
オレイルアルコール２６９ｇ（１モル）をオートクレーブに仕込み、触媒として水酸化カリウム０．７ｇを加えた後、オートクレーブ内を充分に窒素で置換した。攪拌しながら、反応温度を１１５〜１２５℃に維持し、エチレンオキサイド２６４ｇ（６モル）を圧入して付加反応を行なった。圧入終了後、同温度で１時間熟成した後、反応温度を１２０〜１３５℃に維持し、プロピレンオキサイド２３２０ｇ（４０モル）を圧入して付加反応を行なった。圧入終了後、同温度で２時間熟成して反応を終了し、生成物を得た。この生成物を吸着材を用いて濾別精製した。これを分析したところ、式１中のＲ^１が９−オクタデセニル基、Ａ^１がオキシエチレン単位の繰り返し数６のポリエチレングリコールから全ての水酸基を除いた残基、Ａ^２がオキシプロピレン単位の繰り返し数４０のポリプロピレングリコールから全ての水酸基を除いた残基である場合の式１で示されるブロック共重合体（Ａ−１）であった。
【００６５】
・ブロック共重合体（Ａ−２）〜（Ａ−６）及び（ＡＲ−１）〜（ＡＲ−５）の合成
ブロック共重合体（Ａ−１）の合成と同様にして、ブロック共重合体（Ａ−２）〜（Ａ−６）及び（ＡＲ−１）〜（ＡＲ−５）を合成した。以上で合成したブロック共重合体（Ａ−１）〜（Ａ−６）及び（ＡＲ−１）〜（ＡＲ−５）の内容を表１にまとめて示した。
【００６６】
【表１】

【００６７】
試験区分２（粉末状消泡剤の製造）
・粉末状消泡剤（Ｍ−１）の製造
Ｂ成分としての多孔質シリカ微粉末（比表面積１６０ｍ^２／ｇ、平均粒径８０μｍ）７．９ｋｇをリボンミキサーに仕込んだ。別にＡ成分としてのブロック共重合体（Ａ−１）１２ｋｇとＣ成分としてのハイドロキノン０．０４ｋｇとを予め混合しておき、その混合物を前記のリボンミキサーに攪拌しながら少しずつ分割添加し、充分に混合したのち、篩を用いて分級し、粒径１〜５００μｍで、且つ平均粒子径１６０μｍの粉末状消泡剤（Ｍ−１）２０ｋｇを得た。
【００６８】
・粉末状消泡剤（Ｍ−２）〜（Ｍ−８）及び（Ｒ−１）〜（Ｒ−１４）の製造
粉末状消泡剤（Ｍ−１）の製造と同様にして、粉末状消泡剤（Ｍ−２）〜（Ｍ−８）及び（Ｒ−１）〜（Ｒ−１４）を得た。粉末状消泡剤（Ｍ−１）を含め、製造した各粉末状消泡剤の内容を表２にまとめて示した。
【００６９】
【表２】

【００７０】
表２において、
粒径：振動篩の篩目開きから求めた値
平均粒径：分級した粉末状消泡剤を走査型電子顕微鏡で写真撮影し、この写真撮影の画像から１００個の粒子を任意に選定して、選定した個々の粒子について長径（粒子の中心を通る最長の径ｄ１）と短径（粒子の中心を通る最短の径ｄ２）を測定し、（ｄ１＋ｄ２）／２から求めた平均値
【００７１】
Ａ−１〜Ａ−６，ＡＲ−１〜ＡＲ−５：表１に記載のブロック共重合体
ＡＲ−６：分子中のＲ^１、オキシエチレン単位の繰り返し数及びオキシプロピレン単位の繰り返し数はＡ−１と同じであるが、Ａ−１のようにオキシエチレン単位とオキシプロピレン単位とをブロック状に付加したものではなく、オキシエチレン単位とオキシプロピレン単位とをランダム状に付加したもの
【００７２】
Ｂ−１：比表面積１６０ｍ^２／ｇで、且つ平均粒径８０μｍの多孔質シリカ微粉末
Ｂ−２：比表面積１８０ｍ^２／ｇで、且つ平均粒径８５μｍの多孔質シリカ微粉末
Ｂ−３：比表面積１４０ｍ^２／ｇで、且つ平均粒径７５μｍの多孔質シリカ微粉末
Ｂ−４：比表面積２２０ｍ^２／ｇで、且つ平均粒径６０μｍの多孔質シリカ微粉末
Ｂ−５：比表面積１１０ｍ^２／ｇで、且つ平均粒径７０μｍの多孔質シリカ微粉末
【００７３】
Ｃ−１：ハイドロキノン
Ｃ−２：ジブチルヒドロキシトルエン
Ｃ−３：ジブチルヒドロキシアニソール
【００７４】
＊１：比表面積２０ｍ^２／ｇ、平均粒径０．３μｍのシリカフューム微粉末
＊２：比表面積０．８ｍ^２／ｇ、平均粒径２．５μｍの炭酸カルシウム微粉末
＊３：Ｒ−１及びＲ−１０〜Ｒ−１４は粉末状にならなかったので、粒径及び平均粒径を求めなかった。
【００７５】
試験区分３（経時処理した粉末状消泡剤の調製）
試験区分２で製造した粉末状消泡剤Ｍ−１〜Ｍ−８及びＲ−２〜Ｒ−９をシャーレに２０ｇ採取し、４０℃の熱風乾燥器に３０日間放置して、経時処理した粉末状消泡剤Ｍ−１〜Ｍ−８及びＲ−２〜Ｒ−９を調製した。
【００７６】
試験区分４（粉末状分散剤の製造）
・粉末状分散剤（Ｐ−１）の製造
メタクリル酸１０７部（１．２４モル）、メタリルスルホン酸ナトリウム３８部（０．２４モル）、メチルアクリレート２１部（０．２４モル）、メトキシポリエトキシエチル（６８）メタクリレート４９５部（０．１６モル）、メトキシポリエトキシエチル（９）メタクリレート６０部（０．１２モル）及び水８００部を反応容器に仕込み、水酸化ナトリウムの３０％水溶液１６５部を投入して中和し、均一に溶解した後，雰囲気を窒素置換した。反応系の温度を温水浴にて６０℃に保ち、過硫酸ナトリウムの２０％水溶液５５部を投入して重合を開始し、６時間重合反応を継続して重合を完結した。その後、酸性分解物の中和のために３０％水酸化ナトリウム水溶液６部を投入し、水溶性ビニル共重合体（Ｄ−１）の４２％水溶液を得た。この水溶性ビニル共重合体（Ｄ−１）をＮＭＲ測定、元素分析、滴定分析、ゲルパーミエイションクロマトグラフィー（ＧＰＣ）測定等で分析したところ、全構成単位中に、メタクリル酸ナトリウムから形成された構成単位／メタリルスルホン酸ナトリウムから形成された構成単位／メチルアクリレートから形成された構成単位／メトキシポリエトキシ（６８）メタクリレートから形成された構成単位／メトキシポリエトキシ（９）メタクリレートから形成された構成単位＝６２／１２／１２／８／６（モル％、合計１００モル％）の割合で有する数平均分子量１４６００の水溶性ビニル共重合体であった。水溶性ビニル共重合体（Ｄ−１）の４２％水溶液６００部に亜硫酸ナトリウム塩（Ｅ−１）１．３部を加え、ハンドミキサーで撹拌混合し、これを１Ｌのニーダ型混練機に入れて、８０〜１００℃の温度下、４０００Ｐａの減圧下に乾燥しながら粉砕し、更に篩目開き７００μｍの振動篩で分級して、粉末状分散剤（Ｐ−１）を得た。
【００７７】
・粉末状分散剤（Ｐ−２）〜（Ｐ−４）の製造
粉末状分散剤（Ｐ−１）と同様にして、粉末状分散剤（Ｐ−２）〜（Ｐ−４）を得た。粉末状分散剤（Ｐ−１）〜（Ｐ−４）の製造に用いた水溶性ビニル共重合体の内容を表３にまとめて示し、また粉末状分散剤（Ｐ−１）〜（Ｐ−４）の内容を表４にまとめて示した。
【００７８】
【表３】

【００７９】
表３において、
ａｍ−１：メタクリル酸ナトリウム
ｂｍ−１：メタリルスルホン酸ナトリウム
ｂｍ−２：ｐ−メタリルオキシベンゼンスルホン酸ナトリウム
ｃｍ−１：メチルアクリレート
ｄｍ−１：メトキシポリエトキシエチル（６８）メタクリレート
ｄｍ−２：メトキシポリエトキシエチル（９５）メタクリレート
ｄｍ−３：メトキシポリエトキシエチル（９）メタクリレート
ｄｍ−４：メトキシポリエトキシエチル（２３）メタクリレート
ｅｍ−１：メトキシポリエチレングリコール（２４）アリルエーテル
ｅｍ−２：メトキシポリエチレングリコール（３２）アリルエーテル
【００８０】
【表４】

【００８１】
表４において、
粒径及び平均粒径：粒径は振動篩の篩目開きから求めた。また平均粒径は、分級した粉末を走査型電子顕微鏡で写真撮影し、この写真撮影の画像から１００個の粒子を任意に選定して、選定した個々の粒子について長径（粒子の中心を通る最長の径＝ＤＬ）と短径（粒子の中心を通る最短の径＝ＤＳ）を計測し、（ＤＬ＋ＤＳ）／２の平均値で求めた。
Ｄ−１〜Ｄ−４：表３に記載の水溶性ビニル共重合体
Ｅ−１：亜硫酸ナトリウム塩
Ｅ−２：チオ硫酸ナトリウム塩
Ｅ−３：消石灰／亜硝酸カルシウム＝６５／３５（重量比）の混合物
Ｅ−４：消石灰／亜硝酸カルシウム／硝酸カルシウム＝２５／４０／３５（重量比）の混合物
【００８２】
試験区分５（セメントプレミックス製品の調製）
５Ｌのホバートミキサーにアルミナセメント（太平洋セメント社製、比重３．０、ブレーン値５０７０）又は早強ポルトランドセメント（太平洋セメント社製、比重３．１３、ブレーン値４３４０）と、試験区分４で製造した粉末状分散剤と、試験区分２で製造した粉末状消泡剤又は試験区分３で経時処理して調製した粉末状消泡剤とを、表５に記載の割合で乾式混合し、セメントプレミックス製品を調製した。内容を表５にまとめて示した。
【００８３】
【表５】

【００８４】
表５において、
Ｆ−１：アルミナセメント（太平洋セメント社製、比重３．０、ブレーン値５０７０）
Ｆ−２：早強ポルトランドセメント（太平洋セメント社製、比重３．１３、ブレーン値４３４０）
Ｍ−１〜Ｍ−８，Ｒ−２〜Ｒ−９：試験区分２で製造した表２に記載の粉末状消泡剤又は試験区分３で経時処理して調製した粉末状消泡剤
Ｐ−１〜Ｐ−４：試験区分４で製造した表４に記載の粉末状消泡剤
【００８５】
試験区分６（セメントペーストの調製と評価）
試験区分５で調製したセメントプレミックス製品１７００部に水４７０部を加え、２０℃の温度下で３分間混練してフロー値が２５０±２０ｍｍの範囲のセメントペーストを調製した。調製したセメントペーストの空気量及び圧縮強度を下記のように測定した。ここで粉末状消泡剤の消泡性能は空気量の少ないほど良好である。結果を表６にまとめて示した。
・空気量：ＪＩＳ−Ｒ５２０１に準拠して測定した。
・圧縮強度：材齢２８日において、ＪＩＳ−Ｒ５２０１に準拠して測定した。
【００８６】
【表６】

【００８７】
試験区分７（セメントプレミックス製品の調製）
５Ｌのホバートミキサーにアルミナセメント（太平洋セメント社製、比重３．０、ブレーン値５０７０）と、細骨材（ＪＩＳ−Ｒ５２０１の標準砂、比重２．６４）と、試験区分４で製造した粉末状分散剤と、試験区分２で製造した粉末状消泡剤又は試験区分３で経時処理して調製した粉末状消泡剤とを表７に記載の割合で乾式混合し、セメントプレミックス製品を調製した。内容を表７にまとめて示した。
【００８８】
【表７】

【００８９】
表７において、
Ｆ−１：アルミナセメント（太平洋セメント社製、比重３．０、ブレーン値５０７０）
Ｇ−１：ＪＩＳ−Ｒ５２０１の標準砂（比重２．６４）
Ｍ−１〜Ｍ−８，Ｒ−２〜Ｒ−９：試験区分２で製造した表２に記載の粉末状消泡剤又は試験区分３で経時処理して調製した粉末状消泡剤
Ｐ−１〜Ｐ−４：試験区分４で製造した表４に記載の粉末状消泡剤
【００９０】
試験区分８（モルタルの調製と評価）
試験区分７で調製したセメントプレミックス製品５０６７部に水５０５部を加え、２０℃の温度下で３分間混練してフロー値が２２０±２０ｍｍの範囲のモルタルを調製した。調製したモルタルの空気量及び圧縮強度を下記のように測定した。ここで粉末状消泡剤の消泡性能は空気量の少ないほど良好である。結果を表８にまとめて示した。
・空気量：ＪＩＳ−Ｒ５２０１に準拠して測定した。
・圧縮強度：材齢２８日において、ＪＩＳ−Ｒ５２０１に準拠して測定した。
【００９１】
【表８】

【００９２】
【発明の効果】
既に明らかなように、以上説明した本発明には、粉末状分散剤として水溶性ビニル共重合体を含有するものを配合したセメントプレミックス製品において、経日的に保存した粉末状消泡剤を配合した場合であっても、連行空気量を充分に低く制御できるという効果がある。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a cement premix product. A cement premix product in which at least cement, a powdery dispersant, and a powdery antifoaming agent are mixed with a grout filler, a self-leveling floor material, and the like is used. The present invention relates to an improvement in a cement premix product containing a cement premix product containing a water-soluble vinyl copolymer as a powdery dispersant.
[0002]
[Prior art]
Conventionally, as a cement premix product, a product containing at least cement, a powdery dispersant, a powdery defoamer, and the like has been generally used. In such a cement premix product, as the powdered defoaming agent, one composed of powdered silica and polyalkylene glycols (Japanese Patent Publication No. 1-34088), and one in which a polyoxyalkylene compound is absorbed in porous silica fine powder ( JP-A-10-226550) is known. However, among the cement premix products containing these powdered defoamers, in the case of cement premix products containing those containing a water-soluble vinyl copolymer as a powdery dispersant, the entrained air volume is low. In particular, when a powdered antifoaming agent stored over time is blended, there is a problem that the entrained air amount is further increased.
[0003]
[Problems to be solved by the invention]
The problem to be solved by the present invention is that a cement premix product containing a water-soluble vinyl copolymer as a powdery dispersant is blended with a powdered defoamer stored over time. Even so, there is a need to provide a cement premix product that can control the amount of entrained air sufficiently low.
[0004]
[Means for Solving the Problems]
The present inventors have studied to solve the above-mentioned problems, and as a result, at least cement, a powdery dispersant and a powdery antifoaming agent are blended, and a water-soluble vinyl copolymer is used as the powdery dispersant. It has been found that, in a cement premix product containing the components contained therein, a product containing a predetermined ratio of three specific components as a powdery antifoaming agent is correctly and suitably used.
[0005]
That is, the present invention relates to a cement premix product containing at least cement, a powdery dispersant and a powdery defoamer, and containing a water-soluble vinyl copolymer as the powdery dispersant. As an antifoaming agent, the following A component, B component and C component are used, and the A component is 15 to 74% by weight, the B component is 25 to 84% by weight, and the C component is 0.001 to 1% by weight. (Total 100% by weight).
[0006]
A component: block copolymer represented by the following formula 1
(Equation 1)

[0007]
In Equation 1,
R ¹ : An aliphatic hydrocarbon group having 12 to 22 carbon atoms
A ¹ : A residue obtained by removing all hydroxyl groups from polyethylene glycol having a repeating number of 2 to 15 oxyethylene units
A ² : Residue obtained by removing all hydroxyl groups from polypropylene glycol having a repeating number of 10 to 70 oxypropylene units
[0008]
Component B: porous silica fine powder
Component C: Antioxidant
[0009]
The cement premix product of the present invention comprises at least cement, a powdery dispersant containing a water-soluble vinyl copolymer, and a specific powdery defoamer. As a powdery dispersant itself containing cement and a water-soluble vinyl copolymer, a known dispersant itself can be used, and these will be described later. First, a specific powdery defoamer will be described. .
[0010]
The powdered defoamer used in the cement premix product of the present invention comprises the above-mentioned components A, B and C. The component A of the powdery antifoaming agent is a block copolymer represented by the formula 1. In such a block copolymer, an aliphatic hydrocarbon group and a polyoxyethylene group are connected by an ether bond, and a polyoxypropylene group is connected to the polyoxyethylene group by an ether bond. It has a structure in which a hydroxyl group is bonded to one end of the group. The block copolymer having such a structure can be obtained, for example, by subjecting an aliphatic alcohol to addition polymerization of ethylene oxide and then further adding propylene oxide.
[0011]
In the component A of the powdery defoamer, R in the formula 1 ¹ 1) dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, heneicosyl, docosyl, isotridecyl, 5-methyl-4-propylnonyl , A saturated aliphatic hydrocarbon group having 12 to 22 carbon atoms such as 2,7,8-trimethyldecyl group, and 2) an unsaturated hydrocarbon group having 12 to 22 carbon atoms such as 8-hexadecenyl group, 9-octadecenyl group and 10-eicosenyl group. Examples thereof include a saturated aliphatic hydrocarbon group, and among them, an unsaturated aliphatic hydrocarbon group is preferable, and a 9-octadecenyl group is more preferable.
[0012]
In the A component of the powdered defoamer, A in the formula 1 ¹ Is a residue obtained by removing all hydroxyl groups from polyethylene glycol having a repeating number of 2 to 15 oxyethylene units, ¹ Preferably, the residue is obtained by removing all hydroxyl groups from polyethylene glycol having 4 to 10 repeating oxyethylene units.
[0013]
In the A component of the powdered defoamer, A in the formula 1 ² Is a residue obtained by removing all hydroxyl groups from polypropylene glycol having a repeating number of 10 to 70 oxypropylene units, ² Preferably, the residue is obtained by removing all hydroxyl groups from polypropylene glycol having a repeating number of 20 to 50 oxypropylene units.
[0014]
The block copolymer represented by Formula 1 as the component A of the powdery antifoaming agent can be synthesized by a known method. For example, it can be synthesized by a method of subjecting an aliphatic alcohol to an addition polymerization reaction of ethylene oxide under heating and pressurization using an alkali catalyst, followed by an addition polymerization reaction of propylene oxide.
[0015]
The B component of the powdered defoaming agent is a porous silica fine powder. As such porous silica fine powder, known ones can be used, and among them, the specific surface area is 50 to 450 m. ² / G and an average particle size in the range of 0.1 to 500 µm, more preferably 1 to 99 µm. In particular, the oil absorption (oil absorption according to JIS-K5101-19) is 100 m. ² / G is preferable.
[0016]
The C component of the powdered defoamer is an antioxidant. As the antioxidant, known ones can be used, and examples thereof include hydroquinone, hydroquinone monomethyl ether, phenothiazine, dibutylhydroxytoluene, butylhydroxyanisole, tributyl phosphite, and triphenyl phosphite. Of these, hydroquinone, dibutylhydroxytoluene and butylhydroxyanisole are preferred. One or two or more of these antioxidants can be used.
[0017]
The powdered defoaming agent used in the cement premix product of the present invention contains 15 to 74% by weight of the component A, 25 to 84% by weight of the component B, and 0.001 to 1% by weight of the component C as described above ( (A total of 100% by weight), the component A being 30 to 69.5% by weight, the component B being 30 to 69.5% by weight, and the component C being 0.05 to 0.5% by weight (total). 100% by weight).
[0018]
The powdered defoaming agent used in the cement premix product of the present invention is, for example, a component equipped with a stirring blade, the A component, the B component and the C component at a predetermined ratio, first put the B component, then It can be manufactured by charging a mixture in which the component A and the component C are mixed in advance little by little with stirring and uniformly mixing. The product obtained here is usually in the form of a powder having a particle size of 3000 μm or less. When such a powdery antifoaming agent is used in the cement premix product of the present invention, the particle size should be uniform. It is preferable that the particles are classified using a sieve so that the particle diameter is 1 to 2000 μm and the average particle diameter is 1 to 1500 μm.
[0019]
The powdery dispersant used in the cement premix product of the present invention contains a water-soluble vinyl copolymer. As such a powdery dispersant, known ones can be used, but those obtained by drying and pulverizing an aqueous mixture of the following components D and E are preferable.
[0020]
Component D: 1) 40 to 80 mol% of the structural unit A formed from the vinyl monomer represented by the following formula 2 in all the structural units, and formed from the vinyl monomer represented by the following formula 3 The structural unit B is formed from 1 to 25 mol%, the structural unit C formed from the vinyl monomer represented by the following formula 4 is 3 to 20 mol%, and the vinyl monomer represented by the following formula 5 is formed. Water-soluble vinyl copolymer having a number average molecular weight of 2,000 to 70,000 having 1 to 45 mol% (total 100 mol%) of the structural units D, 2) a vinyl monomer represented by the following formula 2 in all the structural units 40 to 70 mol% of a structural unit A formed from the following, 5 to 30 mol% of a structural unit B formed from a vinyl monomer represented by the following formula 3, and a vinyl monomer represented by the following formula 4 1 to 20 mol% of a structural unit C formed from 1 to 30 mol% of the structural unit D formed from the vinyl monomer and 1 to 30 mol% of the structural unit E formed from the vinyl monomer represented by the following formula 6 (total 100 mol%). Water-soluble vinyl copolymer having a number average molecular weight of 2,000 to 70,000, one or more selected from the above 1) and 2)
[0021]
E component: alkali metal sulfite, alkaline earth metal sulfite, alkali metal thiosulfate, alkaline earth metal thiosulfate, hydroxide of alkaline earth metal, alkaline earth metal nitrate, metal nitrate, nitrite One or more selected from alkaline earth metal nitrates and metal nitrites
[0022]
[Equation 2]

[0023]
[Equation 3]

[0024]
(Equation 4)

[0025]
(Equation 5)

[0026]
(Equation 6)

[0027]
In Equations 2 to 6,
R ² , R ³ , R ⁴ , R ⁵ , R ⁷ : Hydrogen atom or methyl group
R ⁶ , R ⁸ : An alkyl group having 1 to 3 carbon atoms
M ¹ : Hydrogen atom, alkali metal, alkaline earth metal, ammonium or organic amine
Z: -SO ₃ M ² Or -OC ₆ H ₄ -SO ₃ M ³ Organic group represented by
(M ² , M ³ ; Alkali metals, alkaline earth metals, ammonium or organic amines)
A ³ : A residue obtained by removing all hydroxyl groups from a polyalkylene glycol having a repeating number of 5-109 oxyalkylene units consisting of only oxyethylene units or both oxyethylene units and oxypropylene units
A ⁴ : A residue obtained by removing all hydroxyl groups from a polyalkylene glycol having a repeating number of 5 to 50 of an oxyalkylene unit consisting of only an oxyethylene unit or both an oxyethylene unit and an oxypropylene unit
[0028]
The D component of the powdery dispersant includes 1) a structural unit A formed from a vinyl monomer represented by the formula 2, a structural unit B formed from a vinyl monomer represented by the formula 3, and 4 Water-soluble vinyl copolymer having a predetermined ratio of a structural unit C formed from a vinyl monomer to be formed and a structural unit D formed from a vinyl monomer represented by a formula 5 in a predetermined ratio; Structural unit A formed from a monomer, Structural unit B formed from a vinyl monomer represented by Formula 3, Structural unit C formed from a vinyl monomer represented by Formula 4, and represented by Formula 5 A water-soluble vinyl copolymer having a predetermined ratio of a structural unit D formed from a vinyl monomer and a structural unit E formed from a vinyl monomer represented by the formula 6; Mixtures are included. Such a water-soluble vinyl copolymer can be obtained by radical copolymerization of a vinyl monomer which forms the structural units A to D or the structural units A to E, respectively.
[0029]
Examples of the vinyl monomer represented by Formula 2 that forms the structural unit A include: 1) methacrylic acid, acrylic acid, 2) an alkali metal salt, an alkaline earth metal salt or an organic amine salt of methacrylic acid, 3) There are alkali metal salts, alkaline earth metal salts and organic amine salts of acrylic acid. Of these, alkali metal salts of methacrylic acid such as sodium and potassium are preferred.
[0030]
Examples of the vinyl monomer represented by the formula 3 which forms the structural unit B include 1) an alkali metal salt, an alkaline earth metal salt or an organic amine salt of (meth) allylsulfonic acid, and 2) p-methallyl. There are alkali metal salts, alkaline earth metal salts and organic amine salts of oxybenzenesulfonic acid. Among them, alkali metal salts of methallylsulfonic acid such as sodium and potassium are preferable.
[0031]
Examples of the vinyl monomer represented by Formula 4 that forms the structural unit C include methyl acrylate and methyl methacrylate.
[0032]
Examples of the vinyl monomer represented by the formula 5 that forms the structural unit D include: 1) an alkoxypolyethylene glycol having an alkyl group having 1 to 3 carbon atoms and having 5 to 109 repeating oxyethylene units ( 2) an alkoxypolyalkylene glycol (meth) acrylate having an alkyl group having 1 to 3 carbon atoms, wherein the total number of repeating oxyethylene units and repeating oxypropylene units is 5 to 109; The mixture of 1) and the above 2) is mentioned. Examples thereof include methoxypolyethoxyethyl (meth) acrylate, ethoxypolyethoxyethyl (meth) acrylate, n-propoxypolyethoxyethyl (meth) acrylate, and isopropoxypolyethoxyethyl (meth) acrylate. However, methoxypolyethoxyethyl methacrylate having a repeating number of oxyethylene units of 7 to 100 is preferable.
[0033]
Examples of the vinyl monomer represented by the formula 6 that forms the structural unit E include: 1) an alkoxypolyethylene glycol having an alkyl group having 1 to 3 carbon atoms and having 5 to 50 repeating oxyethylene units; (Meth) allyl ether, 2) alkoxypolyalkylene glycol (meth) allyl ether having an alkyl group having 1 to 3 carbon atoms, wherein the total number of repeating oxyethylene units and repeating oxypropylene units is 5 to 50; A) a mixture of the above 1) and 2). Among them, methoxypolyethylene glycol methallyl ether having a repeating number of oxyethylene units of 7 to 35 is preferable.
[0034]
The water-soluble vinyl copolymer as described above to be provided to the powdery dispersant is a vinyl monomer as described above, which forms the structural units A to D or the structural units A to E in the presence of a radical initiator. It can be obtained by subjecting the polymer to radical copolymerization so as to have a predetermined copolymerization ratio. Such radical copolymerization is usually carried out by aqueous solution polymerization using water as a solvent. More specifically, first, each vinyl monomer is dissolved in water to prepare an aqueous solution containing each vinyl monomer in a total amount of 10 to 45% by weight. Next, a radical initiator is added to the prepared aqueous solution under a nitrogen gas atmosphere, and a radical copolymerization reaction is performed at 50 to 70 ° C. for 5 to 8 hours to obtain a water-soluble vinyl copolymer. The type of the radical initiator used is not particularly limited as long as it decomposes at the temperature of the copolymerization reaction and generates a radical, but a water-soluble radical initiator is preferably used. Examples of such a water-soluble radical initiator include persulfates such as sodium persulfate, potassium persulfate, and ammonium persulfate.
[0035]
When the water-soluble vinyl copolymer thus obtained is composed of constitutional units A to D, the constitutional unit A is contained in 40 to 80 mol%, preferably 55 to 72 mol%, in all the constitutional units. B is 1 to 25 mol%, preferably 3 to 18 mol%, structural unit C is 3 to 20 mol%, preferably 4 to 15 mol%, and structural unit D is 1 to 45 mol%, preferably 3 to 25 mol%. % (Total 100 mol%). When it is composed of the structural units A to E, the structural unit A is 40 to 70 mol%, preferably 55 to 68 mol%, and the structural unit B is 5 to 30 mol%, preferably, in all the structural units. 6 to 18% by mole, 1 to 20% by mole, preferably 3 to 15% by mole of structural unit C, 1 to 30% by mole, preferably 3 to 15% by mole of structural unit D, and 1 to 30% by mole of structural unit E %, Preferably 2 to 25 mol% (total 100 mol%). The number-average molecular weight is in the range of 2,000 to 70,000 (GPC method, pullulan conversion, the same applies hereinafter), but preferably in the range of 3,000 to 45,000.
[0036]
The E component used for the cement dispersant includes 1) alkali metal sulfites such as potassium sulfite and sodium sulfite, 2) alkaline earth metal sulfites such as calcium sulfite and magnesium sulfite, 3) potassium thiosulfate, sodium thiosulfate and the like. 4) Alkaline earth metal thiosulfate such as calcium thiosulfate and magnesium thiosulfate 5) Water of alkaline earth metal such as calcium hydroxide (slaked lime), barium hydroxide and strontium hydroxide Oxides, 6) alkaline earth metal salts such as calcium nitrate and magnesium nitrate, 7) metal nitrates such as iron nitrate and copper nitrate, 8) alkaline earth metal salts such as calcium nitrite and magnesium nitrite , 9) metal nitrites such as iron nitrite and copper nitrite, 10) a mixture of two or more selected from the above 1) to 9) There may be mentioned, among others calcium hydroxide (slaked lime), calcium nitrate, calcium nitrite, sodium sulfite, sodium thiosulfate is preferred.
[0037]
The powdery dispersant used as a preferable material in the cement premix product of the present invention is obtained by drying and pulverizing an aqueous mixture of the water-soluble vinyl copolymer as the D component and the inorganic compound as the E component. It is.
[0038]
The aqueous mixture in this case means a mixture of a water-soluble vinyl copolymer as the D component and an inorganic compound as the E component in a system mainly containing water, usually an aqueous solution. Therefore, when the water-soluble vinyl copolymer as the component D is obtained as an aqueous solution by the above-described aqueous solution polymerization, it can be used as it is and mixed with the inorganic compound as the component E.
[0039]
The D component and the E component are as follows: 1) When the E component is an alkali metal sulfite, an alkaline earth metal sulfite, an alkali metal thiosulfate, or an alkaline earth metal thiosulfate, D component / E component = 99.99. It is preferable to carry out aqueous mixing so as to have a ratio of /0.01 to 97/3 (weight ratio), and D component / E component = 99.5 / 0.5 to 97.5 / 2.5 (weight ratio). It is more preferable to carry out aqueous mixing so as to obtain the ratio. 2) When the E component is a hydroxide of an alkaline earth metal, an alkaline earth metal nitrate, a metal nitrate, an alkaline earth metal nitrite or a metal nitrite, the D component / E component = 10/90. It is preferable to carry out aqueous mixing so as to have a ratio of ９０90/10 (weight ratio), and it is more preferable to carry out aqueous mixing such that the ratio of D component / E component = 25/75 to 75/25 (weight ratio).
[0040]
The means for drying and pulverizing the aqueous mixture of the component D and the E component is as follows: 1) when both are aqueously mixed and then dried and then pulverized; 2) when both are aqueously mixed and dried and then pulverized. In some cases, 3) when both are aqueous-mixed and then pulverized while drying, and 4) both aqueous-mixing, drying and pulverization may be performed in parallel. More specifically, for example, when the solid content concentration of the mixture of the aqueous solution of the water-soluble vinyl copolymer as the component D and the inorganic compound as the component E is 5 to 40% by weight, An inorganic compound is added to the combined aqueous solution, mixed at a temperature of 60 to 100 ° C., dried using a spray drier or a flash jet drier, and then pulverized to obtain a powdery dispersant. For example, when the solid content concentration of a mixture of the aqueous solution of the water-soluble vinyl copolymer as the component D and the inorganic compound as the component E exceeds 40% by weight, the aqueous solution of the water-soluble vinyl copolymer is used. An inorganic compound is added to the mixture, and the mixture is dried while being mixed at a temperature of 60 to 120 ° C. using a stirring and kneading dryer or a band-type continuous vacuum dryer, and then pulverized to obtain a powdery dispersant.
[0041]
The powdery dispersant thus obtained can be used as it is in the production of the cement premix product of the present invention, but from the convenience in producing the cement premix product using this, it is further classified. It is preferable that the particles have the same particle size. In this case, classification may be performed while pulverizing, or may be performed after pulverizing. When the aqueous mixture of the D component and the E component is dried and pulverized, or further classified, the particle size of the resulting powdery dispersant is 3000 μm or less and the average particle size is small. The diameter is preferably 5 to 2000 μm, more preferably 700 μm or less and the average particle diameter is 5 to 500 μm.
[0042]
In the cement premix product of the present invention, as the cement, in addition to various portland cements such as ordinary portland cement, early-strength portland cement, moderately heated portland cement, high belite portland cement, etc., blast furnace cement, fly ash cement, silica fume cement Various types of mixed cements and alumina cements can be used, and among them, in the case where the construction time is required to be shortened, early-strength alumina cement and early-strength Portland cement are preferable.
[0043]
The cement premix product of the present invention contains at least cement, a powdery dispersant, and a powdery defoamer as described above. Examples of such a cement premix product include 1) cement, powdery dispersion Premix product in which an agent and a powdery antifoaming agent are blended, 2) cement, a fine aggregate, a cement premix product in which a powdery dispersing agent and a powdery antifoaming agent are blended.
[0044]
In the cement premix product of the present invention, the mixing ratio of the powdery dispersant and the powdery defoamer to the cement is 0.1 to 5 parts by weight of the powdery dispersant per 100 parts by weight of the cement, and the powdery defoamer. It is preferred that the amount of the agent is 0.0005 to 0.02 parts by weight.
[0045]
In particular, when the cement premix product of the present invention does not contain fine aggregate, 0.2 to 1 part by weight of a powdery dispersant and 0.1 to 1 part by weight of a powdery defoamer per 100 parts by weight of cement. 001 to 0.01 parts by weight is more preferable, and when the cement premix product of the present invention contains fine aggregate, the total amount of cement and fine aggregate is 100 parts by weight. More preferably, the amount of the powdery dispersant is 0.1 to 0.5 part by weight, and the amount of the powdery defoamer is 0.0005 to 0.005 part by weight. When the cement premix product of the present invention contains fine aggregate, the ratio of cement and fine aggregate is preferably cement / fine aggregate = 20/80 to 70/30 (weight ratio), More preferably, the ratio is 30/70 to 60/40 (weight ratio).
[0046]
In the cement premix product of the present invention, additives normally used for cement premix products can be used in combination with the purpose. Such additives include a waterproofing agent, a curing accelerator, a curing retarder and the like.
[0047]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments of the cement premix product of the present invention include the following 1) to 16).
1) A cement premix product containing 100 parts by weight of cement, 0.4 parts by weight of the following powdery dispersant (P-1) and 0.002 parts by weight of the following powdery defoamer (M-1).
Powdery dispersant (P-1): D component: 62 mol% of a constituent unit formed from sodium methacrylate in all the constituent units, 12 mol% of a constituent unit formed by sodium methallyl sulfonate, methyl acrylate From methoxypolyethoxyethyl (repeating number of ethoxy units: 68, hereinafter simply referred to as 68) methacrylate, and 8 mol% of methoxypolyethoxyethyl (9) methacrylate. Sodium sulfite (E-1) = 99.5 / 0 as a water-soluble vinyl copolymer (D-1) / E component having a number average molecular weight of 14600 having 6 mol% (100 mol% in total) of the formed structural units. A water-based mixture containing a ratio of 0.5 (weight ratio) was dried, pulverized, and classified to a particle size of less than 700 μm and an average Powdery dispersant diameter 450μm
Powdered antifoaming agent (M-1): The following A component is 60% by weight, the following B component is 39.8% by weight, and the following C component is 0.2% by weight (total 100% by weight). A powdered antifoaming agent having a particle size of 1 to 500 μm, which is mixed and classified, and an average particle size of 160 μm.
A component: R in formula 1 ¹ Is a 9-octadecenyl group, A ¹ Is a residue obtained by removing all hydroxyl groups from polyethylene glycol having a repeating number of 6 of oxyethylene units, A ² Is a residue obtained by removing all hydroxyl groups from polypropylene glycol having a repetition number of oxypropylene units of 40, and the block copolymer represented by the formula (A-1).
B component: specific surface area 160 m ² / G and a porous silica fine powder having an average particle size of 80 μm (B-1)
C component: hydroquinone (C-1)
[0048]
2) A cement premix product containing 100 parts by weight of cement, 0.4 parts by weight of the following powdery dispersant (P-2) and 0.005 parts by weight of the above-mentioned powdery defoamer (M-1).
Powdered dispersant (P-2): 58 mol% of the structural unit formed from sodium methacrylate and 18 mol of the structural unit formed from sodium p-methallyloxybenzenesulfonate as the D component in all the structural units. %, A constitutional unit formed from methyl acrylate at 8 mol%, a constitutional unit formed from methoxypolyethoxyethyl (95) methacrylate at 10 mol%, and a constitutional unit formed from methoxypolyethoxyethyl (23) methacrylate at 6 mol%. Water-soluble vinyl copolymer (D-2) having a number average molecular weight of 9200 having a mole% (total of 100 mole%) / sodium thiosulfate (E-2) as an E component = 98.5 / 1.5 (weight ratio) The water-based mixture containing at a ratio of is dried, pulverized, and classified into a powdery dispersion having a particle size of less than 700 μm and an average particle size of 490 μm. Agent
[0049]
3) A cement premix product containing 100 parts by weight of cement, 0.6 parts by weight of the following powdery dispersant (P-3) and 0.003 parts by weight of the following powdery defoamer (M-2).
Powdery dispersant (P-3): As the D component, 62 mol% of the structural unit formed from sodium methacrylate and 8 mol% of the structural unit formed from sodium methallylsulfonate in all the structural units, p- 5 mol% of the structural unit formed from sodium methallyloxybenzenesulfonate, 2 mol% of the structural unit formed from methyl acrylate, 10 mol% of the structural unit formed from methoxypolyethoxyethyl (23) methacrylate, and Water-soluble vinyl copolymer having a number average molecular weight of 6200 (D-3) having 15 mol% (total 100 mol%) of structural units formed from methoxypolyethylene glycol (24) allyl ether / Slaked lime / calcium nitrite as an E component = 65/35 (weight ratio) mixture (E-3) = 40/60 (weight ratio) The aqueous mixture was dried with and pulverized, classified in particle size of less than 700 .mu.m, and an average particle size 370μm powdery dispersant
Powdered defoaming agent (M-2): 65% by weight of the block copolymer (A-1) as the A component, and 34.93% by weight of the porous silica fine powder (B-1) as the B component. % And the following C component are mixed at a ratio of 0.07% by weight (total 100% by weight) and classified, and the powdered defoaming agent having a particle size of 1 to 500 µm and an average particle size of 180 µm.
C component: dibutylhydroxytoluene (C-2)
[0050]
4) A cement premix product containing 100 parts by weight of cement, 0.3 parts by weight of the following powdery dispersant (P-4) and 0.006 parts by weight of the above powdery defoamer (M-2).
Powdered dispersant (P-4): as a D component, 58 mol% of a structural unit formed from sodium methacrylate in all the structural units, 17 mol% of a structural unit formed from sodium methallylsulfonate, methyl acrylate 8 mol% of the structural unit formed from methoxypolyethoxyethyl (68) methacrylate, and 10 mol% of the structural unit formed from methoxy polyethylene glycol (32) allyl ether. Water-soluble vinyl copolymer having a number average molecular weight of 13,000 (D-4) / a mixture of slaked lime / calcium nitrite / calcium nitrate = 25/40/35 (weight ratio) (E- 4) An aqueous mixture containing 25/75 (weight ratio) was dried, pulverized, and classified to a particle size of 700. Less than m, and an average particle size 410μm powdery dispersant
[0051]
5) A cement premix product containing 100 parts by weight of cement, 0.3 parts by weight of the above powdery dispersant (P-1) and 0.003 parts by weight of the following powdery defoamer (M-3).
Powdered defoaming agent (M-3): 40% by weight of the block copolymer (A-1) as the A component, and 59.6% by weight of the fine porous silica powder (B-1) as the B component. % And the following C component are mixed at a ratio of 0.4% by weight (total 100% by weight), and classified into a powdered defoaming agent having a particle size of 1 to 500 μm and an average particle size of 145 μm.
C component: dibutylhydroxyanisole (C-3)
[0052]
6) A cement premix product comprising 100 parts by weight of cement, 0.6 parts by weight of the powdery dispersant (P-2) and 0.009 parts by weight of the powdery defoamer (M-3).
[0053]
7) A cement premix product containing 100 parts by weight of cement, 0.4 parts by weight of the above powdery dispersant (P-3) and 0.003 parts by weight of the following powdery defoamer (M-4).
Powdered defoamer (M-4): The following component A is 60% by weight, the following component B is 39.8% by weight, and the above component is 0.2% by weight of hydroquinone (C-1) as component C (total). 100% by weight), and a classified anti-foaming agent having a particle size of 1 to 500 μm and an average particle size of 155 μm.
A component: R in formula 1 ¹ Is a 9-octadecenyl group, A ¹ Is a residue obtained by removing all hydroxyl groups from polyethylene glycol having a repeating number of 8 oxyethylene units, A ² Is a residue obtained by removing all hydroxyl groups from polypropylene glycol having a repetition number of 30 oxypropylene units, and the block copolymer represented by the formula 1 (A-2).
B component: specific surface area 180 m ² / G and a porous silica fine powder having an average particle size of 85 μm (B-2)
[0054]
8) A cement premix product containing 100 parts by weight of cement, 0.4 parts by weight of the powdery dispersant (P-4) and 0.006 parts by weight of the powdery defoamer (M-4).
[0055]
9) 33 parts by weight of cement, 67 parts by weight of fine aggregate, 0.2 parts by weight of the powdery dispersant (P-1) and 0.002 parts by weight of the powdery defoamer (M-1) Cement premix products.
[0056]
10) 33 parts by weight of cement, 67 parts by weight of fine aggregate, 0.2 parts by weight of the powdery dispersant (P-2) and 0.003 parts by weight of the powdery defoamer (M-1) Cement premix products.
[0057]
11) 33 parts by weight of cement, 67 parts by weight of fine aggregate, 0.3 parts by weight of the powdery dispersant (P-3) and 0.002 parts by weight of the powdery defoamer (M-2) Cement premix products
[0058]
12) 33 parts by weight of cement, 67 parts by weight of fine aggregate, 0.3 parts by weight of the powdery dispersant (P-4) and 0.003 parts by weight of the powdery defoamer (M-2) Cement premix products.
[0059]
13) 33 parts by weight of cement, 67 parts by weight of fine aggregate, 0.2 parts by weight of the powdery dispersant (P-1) and 0.002 parts by weight of the powdery defoamer (M-3) Cement premix products.
[0060]
14) 33 parts by weight of cement, 67 parts by weight of fine aggregate, 0.3 part by weight of the powdery dispersant (P-2) and 0.005 part by weight of the powdery defoamer (M-3) Cement premix products.
[0061]
15) 33 parts by weight of cement, 67 parts by weight of fine aggregate, 0.2 parts by weight of the powdery dispersant (P-3) and 0.002 parts by weight of the powdery defoamer (M-4) Cement premix products.
[0062]
16) 33 parts by weight of cement, 67 parts by weight of fine aggregate, 0.3 parts by weight of the powdery dispersant (P-4) and 0.003 parts by weight of the powdery defoamer (M-4) Cement premix products.
[0063]
EXAMPLES Hereinafter, examples and the like will be described in order to make the configuration and effects of the present invention more specific, but the present invention is not limited to these examples. In the following Examples and Comparative Examples, parts mean parts by weight, and% means% by weight.
[0064]
【Example】
Test Category 1 (Synthesis of block copolymer)
・ Synthesis of block copolymer (A-1)
After 269 g (1 mol) of oleyl alcohol was charged into the autoclave, 0.7 g of potassium hydroxide was added as a catalyst, and the inside of the autoclave was sufficiently purged with nitrogen. While stirring, the reaction temperature was maintained at 115 to 125 ° C., and 264 g (6 mol) of ethylene oxide was injected to perform an addition reaction. After completion of the injection, the mixture was aged at the same temperature for 1 hour, and the reaction temperature was maintained at 120 to 135 ° C., and 2,320 g (40 mol) of propylene oxide was injected to perform an addition reaction. After the completion of the injection, the mixture was aged at the same temperature for 2 hours to terminate the reaction, thereby obtaining a product. This product was filtered and purified using an adsorbent. When this was analyzed, R ¹ Is a 9-octadecenyl group, A ¹ Is a residue obtained by removing all hydroxyl groups from polyethylene glycol having a repeating number of 6 of oxyethylene units, A ² Is a residue obtained by removing all hydroxyl groups from polypropylene glycol having a repetition number of 40 oxypropylene units, which is the block copolymer (A-1) represented by the formula 1.
[0065]
-Synthesis of block copolymers (A-2) to (A-6) and (AR-1) to (AR-5)
Block copolymers (A-2) to (A-6) and (AR-1) to (AR-5) were synthesized in the same manner as in the synthesis of the block copolymer (A-1). Table 1 summarizes the contents of the block copolymers (A-1) to (A-6) and (AR-1) to (AR-5) synthesized above.
[0066]
[Table 1]

[0067]
Test Category 2 (Production of powdered antifoaming agent)
・ Production of powdered defoamer (M-1)
Porous silica fine powder as component B (specific surface area 160 m ² / G, average particle size 80 μm) was charged into a ribbon mixer. Separately, 12 kg of the block copolymer (A-1) as the component A and 0.04 kg of hydroquinone as the component C are mixed in advance, and the mixture is added in small portions while stirring to the ribbon mixer. After that, the mixture was classified using a sieve to obtain 20 kg of a powdery defoamer (M-1) having a particle size of 1 to 500 µm and an average particle size of 160 µm.
[0068]
-Production of powdered defoamers (M-2) to (M-8) and (R-1) to (R-14)
Powdered defoamers (M-2) to (M-8) and (R-1) to (R-14) were obtained in the same manner as in the production of the powdered defoamer (M-1). Table 2 summarizes the contents of each of the manufactured powdered antifoaming agents including the powdered antifoaming agent (M-1).
[0069]
[Table 2]

[0070]
In Table 2,
Particle size: Value obtained from the opening of the vibrating sieve
Average particle size: The classified powdery defoaming agent is photographed with a scanning electron microscope, and 100 particles are arbitrarily selected from the photographed image. The average value obtained by measuring the longest diameter d1 passing through and the short diameter (shortest diameter d2 passing through the center of the particle) and calculating from (d1 + d2) / 2
[0071]
A-1 to A-6, AR-1 to AR-5: Block copolymers described in Table 1
AR-6: R in the molecule ¹ , The number of repetitions of oxyethylene units and the number of repetitions of oxypropylene units are the same as A-1, except that oxyethylene units and oxypropylene units are not added in blocks as in A-1. Units and oxypropylene units added randomly
[0072]
B-1: Specific surface area 160 m ² / G and an average particle size of 80 μm porous silica fine powder
B-2: Specific surface area 180 m ² / G and porous silica fine powder having an average particle size of 85 μm
B-3: Specific surface area 140m ² / G and an average particle diameter of 75 μm porous silica fine powder
B-4: specific surface area 220 m ² / G and porous silica fine powder having an average particle size of 60 μm
B-5: Specific surface area 110 m ² / G and porous silica fine powder having an average particle size of 70 μm
[0073]
C-1: Hydroquinone
C-2: dibutylhydroxytoluene
C-3: dibutylhydroxyanisole
[0074]
* 1: Specific surface area 20m ² / G, silica fume fine powder with an average particle size of 0.3 μm
* 2: Specific surface area 0.8m ² / G, fine powder of calcium carbonate having an average particle size of 2.5 μm
* 3: Since R-1 and R-10 to R-14 did not become powder, the particle size and average particle size were not determined.
[0075]
Test Category 3 (Preparation of powdered defoamer treated with aging)
20 g of powdered antifoaming agents M-1 to M-8 and R-2 to R-9 produced in Test Category 2 were collected in a Petri dish, left in a 40 ° C. hot air drier for 30 days, and treated with time. Defoamers M-1 to M-8 and R-2 to R-9 were prepared.
[0076]
Test Category 4 (Production of powdered dispersant)
・ Production of powdered dispersant (P-1)
Methacrylic acid 107 parts (1.24 mol), sodium methallylsulfonate 38 parts (0.24 mol), methyl acrylate 21 parts (0.24 mol), methoxypolyethoxyethyl (68) methacrylate 495 parts (0.16 mol) Mol), 60 parts (0.12 mol) of methoxypolyethoxyethyl (9) methacrylate and 800 parts of water were charged into a reaction vessel, neutralized by charging 165 parts of a 30% aqueous solution of sodium hydroxide, and uniformly dissolved. Thereafter, the atmosphere was replaced with nitrogen. The temperature of the reaction system was maintained at 60 ° C. in a warm water bath, and 55 parts of a 20% aqueous solution of sodium persulfate was charged to start polymerization, and the polymerization reaction was continued for 6 hours to complete the polymerization. Thereafter, 6 parts of a 30% aqueous sodium hydroxide solution was added to neutralize the acidic decomposition product, to obtain a 42% aqueous solution of a water-soluble vinyl copolymer (D-1). When this water-soluble vinyl copolymer (D-1) was analyzed by NMR measurement, elemental analysis, titration analysis, gel permeation chromatography (GPC) measurement, etc., it was found that sodium methacrylate was formed in all the constituent units. Structural unit formed from sodium methallyl sulfonate / Structural unit formed from sodium methallyl sulfonate / Structural unit formed from methyl acrylate / Structural unit formed from methoxy polyethoxy (68) methacrylate / Methoxy acrylate (9) It was a water-soluble vinyl copolymer having a number average molecular weight of 14,600 and a constitutional unit of 62/12/12/8/6 (mole%, total 100 mol%). 1.3 parts of sodium sulfite (E-1) was added to 600 parts of a 42% aqueous solution of the water-soluble vinyl copolymer (D-1), and the mixture was stirred and mixed with a hand mixer, and the mixture was placed in a 1 L kneader-type kneader. Then, the mixture was pulverized while drying under a reduced pressure of 4000 Pa at a temperature of 80 to 100 ° C., and further classified with a vibration sieve having an opening of 700 μm to obtain a powdery dispersant (P-1).
[0077]
-Production of powdery dispersants (P-2) to (P-4)
Powdered dispersants (P-2) to (P-4) were obtained in the same manner as for powdered dispersant (P-1). The contents of the water-soluble vinyl copolymers used for the production of the powdery dispersants (P-1) to (P-4) are summarized in Table 3, and the powdery dispersants (P-1) to (P- Table 4 summarizes the contents of 4).
[0078]
[Table 3]

[0079]
In Table 3,
am-1: sodium methacrylate
bm-1: sodium methallylsulfonate
bm-2: sodium p-methallyloxybenzenesulfonate
cm-1: methyl acrylate
dm-1: Methoxypolyethoxyethyl (68) methacrylate
dm-2: Methoxypolyethoxyethyl (95) methacrylate
dm-3: Methoxypolyethoxyethyl (9) methacrylate
dm-4: Methoxypolyethoxyethyl (23) methacrylate
em-1: methoxy polyethylene glycol (24) allyl ether
em-2: methoxy polyethylene glycol (32) allyl ether
[0080]
[Table 4]

[0081]
In Table 4,
Particle size and average particle size: The particle size was determined from the opening of the vibrating sieve. The average particle diameter is determined by taking a photograph of the classified powder with a scanning electron microscope, arbitrarily selecting 100 particles from the photographed image, and selecting the long diameter of the selected individual particle (the longest diameter passing through the center of the particle). Of the particles = DL) and the minor axis (the shortest diameter passing through the center of the particles = DS) were measured, and the average value was (DL + DS) / 2.
D-1 to D-4: water-soluble vinyl copolymers described in Table 3
E-1: sodium sulfite
E-2: thiosulfate sodium salt
E-3: A mixture of slaked lime / calcium nitrite = 65/35 (weight ratio)
E-4: mixture of slaked lime / calcium nitrite / calcium nitrate = 25/40/35 (weight ratio)
[0082]
Test Category 5 (Preparation of cement premix products)
Alumina cement (manufactured by Taiheiyo Cement Corp., specific gravity 3.0, Blaine value 5070) or early-strength Portland cement (manufactured by Taiheiyo Cement Corp., specific gravity 3.13, Blaine value 4340) was produced in a 5 L Hobart mixer in test category 4. The powdery dispersant and the powdery antifoaming agent manufactured in Test Category 2 or the powdery antifoaming agent prepared by aging treatment in Test Category 3 were dry-mixed in the proportions shown in Table 5 to obtain a cement premix. The product was prepared. The contents are summarized in Table 5.
[0083]
[Table 5]

[0084]
In Table 5,
F-1: Alumina cement (manufactured by Taiheiyo Cement Co., specific gravity 3.0, Blaine value 5070)
F-2: Early strength Portland cement (manufactured by Taiheiyo Cement Corporation, specific gravity 3.13, Blaine value 4340)
M-1 to M-8, R-2 to R-9: powdered antifoaming agents described in Table 2 manufactured in Test Category 2 or powdered antifoaming agents prepared by aging treatment in Test Category 3
P-1 to P-4: powdered defoamers described in Table 4 manufactured in Test Category 4
[0085]
Test Category 6 (Preparation and evaluation of cement paste)
470 parts of water was added to 1700 parts of the cement premix product prepared in Test Category 5, and kneaded at a temperature of 20 ° C. for 3 minutes to prepare a cement paste having a flow value in a range of 250 ± 20 mm. The air content and compressive strength of the prepared cement paste were measured as follows. Here, the defoaming performance of the powdered defoamer is better as the amount of air is smaller. The results are summarized in Table 6.
-Air volume: Measured according to JIS-R5201.
-Compressive strength: Measured in accordance with JIS-R5201 at a material age of 28 days.
[0086]
[Table 6]

[0087]
Test Category 7 (Preparation of cement premix products)
A 5L Hobart mixer, alumina cement (manufactured by Taiheiyo Cement Co., specific gravity 3.0, Blaine value 5070), fine aggregate (standard sand of JIS-R5201, specific gravity 2.64), and powder produced in test category 4 The dispersant and the powdered antifoaming agent manufactured in Test Category 2 or the powdered antifoaming agent prepared by aging treatment in Test Category 3 are dry-mixed in the proportions shown in Table 7 to prepare a cement premix product. did. The contents are summarized in Table 7.
[0088]
[Table 7]

[0089]
In Table 7,
F-1: Alumina cement (manufactured by Taiheiyo Cement Co., specific gravity 3.0, Blaine value 5070)
G-1: JIS-R5201 standard sand (specific gravity 2.64)
M-1 to M-8, R-2 to R-9: powdered antifoaming agents described in Table 2 manufactured in Test Category 2 or powdered antifoaming agents prepared by aging treatment in Test Category 3
P-1 to P-4: powdered defoamers described in Table 4 manufactured in Test Category 4
[0090]
Test Category 8 (Mortar preparation and evaluation)
505 parts of water was added to 5067 parts of the cement premix product prepared in Test Category 7, and kneaded at a temperature of 20 ° C. for 3 minutes to prepare a mortar having a flow value of 220 ± 20 mm. The air content and compressive strength of the prepared mortar were measured as follows. Here, the defoaming performance of the powdered defoaming agent is better as the amount of air is smaller. The results are summarized in Table 8.
-Air volume: Measured according to JIS-R5201.
Compressive strength: Measured in accordance with JIS-R5201 at a material age of 28 days.
[0091]
[Table 8]

[0092]
【The invention's effect】
As already clear, in the present invention described above, a powdered defoaming agent stored over time in a cement premix product containing a water-soluble vinyl copolymer-containing one as a powdery dispersant. Even if it is blended, there is an effect that the entrained air amount can be controlled to be sufficiently low.

Claims (11)

In a cement premix product containing at least cement, a powdery dispersant and a powdery defoamer, and containing a water-soluble vinyl copolymer as the powdery dispersant, as a powdery defoamer, It is composed of the following components A, B and C, and the component A is 15 to 74% by weight, the component B is 25 to 84% by weight and the component C is 0.001 to 1% by weight (total 100% by weight). ) A cement premix product characterized by comprising what it contains.
Component A: block copolymer represented by the following formula 1 [Formula 1]

(In Equation 1,
R ¹ : an aliphatic hydrocarbon group having 12 to 22 carbon atoms A ¹ : a residue obtained by removing all hydroxyl groups from polyethylene glycol having a repeating number of oxyethylene units of 2 to 15 A ² : a repeating number of 10 to 70 of oxypropylene units Residue from which all hydroxyl groups have been removed from polypropylene glycol)
B component: fine porous silica powder C component: antioxidant A component of the pulverulent antifoam agent is a residue A ¹ in the formula 1 is obtained by removing all hydroxyl groups from polyethyleneglycol repeated several 4-10 oxyethylene units and repetition A ² is oxypropylene units The cement premix product according to claim 1, which is a block copolymer represented by the formula 1 when the residue is a residue obtained by removing all hydroxyl groups from polypropylene glycol of several 20 to 50. A component of the pulverulent antifoam, cement premix product of claim 1 or 2, wherein a block copolymer of formula 1 where R ¹ in formula 1 is a 9-octadecenyl group. B component of powdered defoamer, a specific surface area ranging from 50 to 450 ² / g, and an average particle size 0.1~500μm of porous silica fine powder cement of any one of claims 1 to 3 which is Premix products. The cement premix product according to any one of claims 1 to 4, wherein the B component of the powdered defoaming agent is a porous silica fine powder having an average particle size of 1 to 99 µm. The cement premix according to any one of claims 1 to 5, wherein the C component of the powdered defoamer is one or more antioxidants selected from hydroquinone, dibutylhydroxytoluene, and butylhydroxyanisole. Product. The cement premix product according to any one of claims 1 to 6, wherein the powdered antifoaming agent has a particle size of 1 to 2000 µm and an average particle size of 1 to 1500 µm. A powdered defoamer containing 30 to 69.5% by weight of component A, 30 to 69.5% by weight of component B, and 0.05 to 0.5% by weight of component C (100% by weight in total). The cement premix product according to any one of claims 1 to 7, which is: The cement premix product according to any one of claims 1 to 8, wherein the powdered antifoaming agent is blended at a ratio of 0.0005 to 0.02 parts by weight per 100 parts by weight of the cement. The cement premix product according to any one of claims 1 to 9, wherein the powdery dispersant is obtained by drying and pulverizing an aqueous mixture of the following D component and E component.
Component D: 1) 40 to 80 mol% of the structural unit A formed from the vinyl monomer represented by the following formula 2 in all the structural units, and formed from the vinyl monomer represented by the following formula 3 The structural unit B is formed from 1 to 25 mol%, the structural unit C formed from the vinyl monomer represented by the following formula 4 is 3 to 20 mol%, and the vinyl monomer represented by the following formula 5 is formed. Water-soluble vinyl copolymer having a number average molecular weight of 2,000 to 70,000 having 1 to 45 mol% (total 100 mol%) of the structural units D, 2) a vinyl monomer represented by the following formula 2 in all the structural units 40 to 70 mol% of a structural unit A formed from the following, 5 to 30 mol% of a structural unit B formed from a vinyl monomer represented by the following formula 3, and a vinyl monomer represented by the following formula 4 1 to 20 mol% of a structural unit C formed from 1 to 30 mol% of the structural unit D formed from the vinyl monomer and 1 to 30 mol% of the structural unit E formed from the vinyl monomer represented by the following formula 6 (total 100 mol%). Water-soluble vinyl copolymer having a number average molecular weight of 2,000 to 70,000, one or more selected from the above 1) and 2) E component: alkali metal sulfite, alkaline earth metal sulfite, alkali metal thiosulfate , One or more selected from alkaline earth metal thiosulfate, hydroxide of alkaline earth metal, alkaline earth metal nitrate, metal nitrate, alkaline earth metal nitrite and metal nitrite [Equation 2]

[Equation 3]

(Equation 4)

(Equation 5)

(Equation 6)

に お い て In Equations 2 to 6,
R ² , R ³ , R ⁴ , R ⁵ , R ⁷ : hydrogen atom or methyl group R ⁶ , R ⁸ : alkyl group having 1 to 3 carbon atoms M ¹ : hydrogen atom, alkali metal, alkaline earth metal, ammonium or organic amine Z: organic group represented by _-SO 3 ^{M 2} or _{-O-C 6 H 4 -SO 3} M 3 (M 2, M 3; alkali metal, alkaline earth metal, ammonium or organic amine)
A ³ : A residue obtained by removing all hydroxyl groups from a polyalkylene glycol having a repeating number of 5 to 109 of only an oxyethylene unit or an oxyalkylene unit composed of both an oxyethylene unit and an oxypropylene unit A ⁴ : Only an oxyethylene unit Or a residue obtained by removing all hydroxyl groups from a polyalkylene glycol having a repeating number of 5 to 50 of an oxyalkylene unit composed of both an oxyethylene unit and an oxypropylene unit. The cement premix product according to any one of claims 1 to 10, wherein the powdery dispersant is blended in an amount of 0.1 to 5 parts by weight per 100 parts by weight of the cement.