JPS58154708A - Production of highly water-absorptive resin - Google Patents
Production of highly water-absorptive resinInfo
- Publication number
- JPS58154708A JPS58154708A JP3591482A JP3591482A JPS58154708A JP S58154708 A JPS58154708 A JP S58154708A JP 3591482 A JP3591482 A JP 3591482A JP 3591482 A JP3591482 A JP 3591482A JP S58154708 A JPS58154708 A JP S58154708A
- Authority
- JP
- Japan
- Prior art keywords
- water
- acrylic acid
- acrylamide
- weight
- polymerization
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Compositions Of Macromolecular Compounds (AREA)
- Polymerisation Methods In General (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は水溶性単量体をジビニル′化合物と共重合させ
て、水不溶性で自重の数百倍の水を吸収する高吸水性樹
脂の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a water-insoluble superabsorbent resin that absorbs several hundred times its own weight of water by copolymerizing a water-soluble monomer with a divinyl' compound.
従来、水を吸収し保持するものとしてはパルプ製品が使
われて米た。しかしなから、パルプの吸水量は自重の１
０倍稈に必要とし、大変かさ高いものとなってしまい、
又、吸水したものに圧力を加えると簡単に水を分離する
欠点を有していた。Traditionally, pulp products have been used to absorb and retain water. However, the amount of water absorbed by pulp is 1 of its own weight.
It is necessary for 0x culm, and it becomes very bulky.
Furthermore, it has the disadvantage that water is easily separated when pressure is applied to something that has absorbed water.
そこで、わずかな重量で多量の水を吸収し、保持する高
吸水性樹脂の開発か種々なされて来た。この高吸水性樹
ｌＩトは自重の数百倍の水を吸収、保持し、しかも、吸
水した状聾で安定なゲルとなり多少の圧力を加えても水
を分離しない特徴を有している。このような高吸水性樹
脂は使い捨ておむつ、ナプキン、微生物の借地、園芸用
保水剤等、巾広い用途を持つている。すでに開発された
高吸水性樹脂としては、澱粉クラフト重合体（特公昭５
３−４６１９９）セルロース変成物（特開昭５Ｏ−８０
３７６）などがあるが、澱粉グラフト重合体は含水ゲル
として長期間使用した場合、澱粉が腐敗するおそれがあ
り、また、セルロース変成物では吸水量がセルロースに
比較してそれほど多々はないという欠点を有している。Therefore, various efforts have been made to develop super absorbent resins that absorb and retain large amounts of water with a small weight. This highly water-absorbent tree absorbs and retains several hundred times its own weight in water, and when it absorbs water, it forms a stable gel and does not separate water even when a certain amount of pressure is applied. Such superabsorbent resins have a wide range of uses, including disposable diapers, napkins, microorganisms, and water retention agents for gardening. As super absorbent resins that have already been developed, starch kraft polymers
3-46199) Cellulose modified product (JP-A-5O-80
376), but starch graft polymers have the disadvantage that if they are used as hydrogels for a long period of time, the starch may rot, and cellulose modified products do not absorb much water compared to cellulose. have.
本発明者らはこの欠点を克服すべく鋭意研究をした結果
、本発明に到達した。The present inventors conducted extensive research to overcome this drawback, and as a result, they arrived at the present invention.
すなわち、本発明は、アクリル酸とアクリルアミドをモ
ル比で７０：３０〜ｔｏｏ ：ｏの範囲で、かつアクリ
ル酸の７０モル％以上が、アンモニウム、アミン又はア
ルカリ金属塩である単量体（Ａ） と、アクリル酸とア
クリルアミド１００重量部に対して０．００５〜０．０
５重量部の水混和性乃至水溶性ジビニル化合物（Ｂ）と
、０．５〜１０重量部のメチルセルロース（Ｃ）を必須
成分として水溶液重合を行うことを特徴とする高吸水性
樹脂の製造方法に関するものである。That is, the present invention provides a monomer (A) in which the molar ratio of acrylic acid and acrylamide is in the range of 70:30 to too:o, and 70 mol% or more of the acrylic acid is ammonium, amine, or alkali metal salt. and 0.005 to 0.0 per 100 parts by weight of acrylic acid and acrylamide.
A method for producing a super-absorbent resin characterized by carrying out aqueous solution polymerization using 5 parts by weight of a water-miscible or water-soluble divinyl compound (B) and 0.5 to 10 parts by weight of methylcellulose (C) as essential components. It is something.
本発明の必須成分である単量体（Ａ）については、この
範囲外、すなわちアクリル酸が７０モル％未満でアクリ
ルアミドのモル比を高めると、含水ゲルの強度は高くな
るが、吸水能が低下してしまい、また、中和度を７０モ
ル％未満にすると、カルボキシル基の解離が充分でな畷
、吸水能の低下が見られる。中和に要する塩基について
は特に限定しないが、好ましくは一価陽イオンが良い。Regarding monomer (A), which is an essential component of the present invention, if the molar ratio of acrylamide is increased outside this range, that is, when the acrylic acid content is less than 70 mol%, the strength of the hydrogel increases, but the water absorption capacity decreases. Furthermore, if the degree of neutralization is less than 70 mol %, the dissociation of carboxyl groups is insufficient and the water absorption capacity is decreased. The base required for neutralization is not particularly limited, but monovalent cations are preferred.
水混和性乃至水溶性ジビニル化合物（Ｂ）としては、例
えば、Ｎ、Ｎ−メチレンビス（メタ）アクリルアミド、
ジ（メタ）アクリル酸テトラエチレングリコール、ジ（
メタ）アクリル酸デカエチレングリコール等があげられ
るが、Ｎ、Ｎ−メチレンビスアクリルアミドが工業的に
好ましい。ジビニル化合物（Ｂ）の量は、アクリル酸と
アクリルアミドの重量のましく、この範囲より少ないと
含水ゲルが半溶解状態となり、又、多いと架橋度が増加
し、いずれも吸水能が′低下し工しまう。Examples of the water-miscible or water-soluble divinyl compound (B) include N,N-methylenebis(meth)acrylamide,
Tetraethylene glycol di(meth)acrylate, di(meth)acrylate
Examples include decaethylene glycol meth)acrylate, but N,N-methylenebisacrylamide is industrially preferred. The amount of divinyl compound (B) should be determined by the weight of acrylic acid and acrylamide; if it is less than this range, the water-containing gel will be in a semi-dissolved state, and if it is too much, the degree of crosslinking will increase, and in both cases the water absorption capacity will decrease. I will put away the work.
更に、本発明の重要な特徴は、前述の単量体（Ａ）とジ
ビニル化合物（Ｂ）を水溶液重合するにあたり、メチル
セルロース（Ｃ）を必須成分として共存させることであ
る。重合時にメチルセルロース（Ｃ）を共存させること
によって得られた高吸水性樹脂は著しい吸水能の上昇が
見られた。この吸水能の向上の理由は明らかではないが
、メチルセルロースが重合の場を提供し、より高性能の
高吸水性樹脂が合成されたのではないかと推測される。Furthermore, an important feature of the present invention is that methylcellulose (C) is allowed to coexist as an essential component during aqueous solution polymerization of the monomer (A) and divinyl compound (B). The superabsorbent resin obtained by coexisting methylcellulose (C) during polymerization showed a significant increase in water absorption capacity. The reason for this improvement in water absorption capacity is not clear, but it is speculated that methylcellulose provides a site for polymerization, and a higher performance superabsorbent resin is synthesized.
共存させるメチルセルロースの量は、アクリル酸とアク
リルアミド１００重１部に対し０．５〜１０重篭部の範
囲が好ましく、この範囲外では吸水能の向、トが期待で
きない、メチルセルロースの置換度については、特に限
定するものではないが、通常市販されている置換度１．
６〜２．０の物で充分である。The amount of methylcellulose to be allowed to coexist is preferably in the range of 0.5 to 10 parts by weight per 1 part by weight of acrylic acid and acrylamide; outside this range, no improvement in water absorption capacity can be expected, and the degree of substitution of methylcellulose is Although not particularly limited, the degree of substitution 1. which is usually commercially available.
6 to 2.0 is sufficient.
重合にあたってはメチルセルロースを所定量、単衆体水
溶液に均一に分散あるいは溶解させておけばよい。For polymerization, a predetermined amount of methylcellulose may be uniformly dispersed or dissolved in an aqueous monomer solution.
本発明品を重合するにあたって開始剤は一般的に使用さ
れているレドックス系、アゾ系など、どのような物を使
用しても良く、特定の開始剤に限定されるものではな（
１゜また重合濃度に関しては、特に限定せず任意の濃度
範囲で選択できるが、乾燥工程を考慮すると、できるだ
け高濃度で行う方カイ有利である。例えば、７０％程度
の高濃度水溶液で重合を行し）発生する重合熱によって
水分を蒸発させてしまし）、そのまま乾燥り稈を経ずに
直接粉砕工程へ持って行４方法も選択できる。また、開
始温度については開始剤の種類４こよって重合を開始さ
せる温度が異なるために開始剤が機能する温度以上で重
合を開始させれば良（、特に限定されるもので１よなし
）。In polymerizing the products of the present invention, any commonly used initiator, such as redox type or azo type, may be used, and the initiator is not limited to a specific initiator.
The polymerization concentration is not particularly limited and can be selected within any concentration range; however, in consideration of the drying process, it is advantageous to carry out the polymerization at a concentration as high as possible. For example, 4 methods can be selected, in which polymerization is carried out with a highly concentrated aqueous solution of about 70% (the water is evaporated by the generated heat of polymerization), and the product is directly taken to the pulverization process without passing through the drying process. Regarding the initiation temperature, since the temperature at which polymerization is initiated differs depending on the type of initiator, it is sufficient to initiate polymerization at a temperature higher than the temperature at which the initiator functions (although there are no particular limitations).
次に本発明を実施例に基づいて更に具体的に説明する力
Ｓ、本発明はその要旨を超えない限り以下の実施例も二
制約されるものではない。Next, the present invention will be explained in more detail based on examples, but the present invention is not limited to the following examples as long as they do not go beyond the gist of the invention.
実施例１
アクリル酸５２７ｇとアクリルアミド１７．３ ｇを蒸
留水２０ｇに溶解し、これに水酸化カリウム３２．８ｇ
を加え、アクリル酸の８０モル％を部分中和した。これ
番こ、Ｎ、Ｎ−メチレンビスアク・リルアミドを０．０
０７，９加え、さら番こ、メチルセルロースを２．５ｇ
加えて攪拌して均一にした。Example 1 527 g of acrylic acid and 17.3 g of acrylamide were dissolved in 20 g of distilled water, and 32.8 g of potassium hydroxide was added to this.
was added to partially neutralize 80 mol% of acrylic acid. This number is 0.0 N,N-methylenebisac-lylamide.
07.9 plus Sarabanko and 2.5g methylcellulose
Add and stir to make it homogeneous.
次に開始剤として、２．２′−アゾヒスイソブチロニト
リＪし０．７Ｓを溶解したアセトン溶液を１ＱｃＣ加え
た。この溶液を８０℃の恒温水槽で加温された箱型容器
（テフロノ加工したガラス繊維素材）の中へ入れて加熱
した。Next, 1QcC of an acetone solution containing 0.7S of 2,2'-azohisisobutyronitrile J was added as an initiator. This solution was placed in a box-shaped container (Teflon-treated glass fiber material) heated in a constant temperature water bath at 80°C.
溶液の温度が上昇すると共に重合反応が開始し、発生す
る重合熱によって水分が蒸発し、含水率の非常に低し）
多孔性の白色固体として高吸水性樹脂を得た。As the temperature of the solution rises, the polymerization reaction begins, and the generated heat of polymerization causes water to evaporate, resulting in a very low water content)
A superabsorbent resin was obtained as a porous white solid.
実施例２
アクリル酸４９．２．！９にアクリルアミド２０．８ｇ
を溶かし、これに２９％アンモニア水を２８．０ｇ加え
て、アクリル酸の７０モル％を中和した。これにＮ、Ｎ
−メチレンビスアクリルアミドを０．０１ｇ加え、さら
蚤こメチルセルロースを５９加えて攪拌して均一にした
。次に開始剤と、して２．２′−アノビス（２−アミジ
ノプロパン）ハイドロクロライド０７ｇを５９の蒸留水
に溶かしたものを加えた。Example 2 Acrylic acid 49.2. ! 20.8g of acrylamide in 9
was dissolved, and 28.0 g of 29% ammonia water was added thereto to neutralize 70 mol% of the acrylic acid. N, N to this
- Added 0.01 g of methylene bisacrylamide, added 59 g of methyl cellulose and stirred to make it homogeneous. Next, an initiator, 07 g of 2,2'-anobis(2-amidinopropane) hydrochloride dissolved in 59 g of distilled water, was added.
この溶液を８０℃の恒温水槽で加温された前述の箱型容
器の中へ入れて加熱し、重合を開始させた。重合反応が
進み、発生する重合熱によって水分が蒸発し、含水率の
非常に低い多孔性の白色固体として高吸水性樹脂を得た
。This solution was placed in the aforementioned box-shaped container heated in a constant temperature water bath at 80° C. and heated to initiate polymerization. As the polymerization reaction progressed, water was evaporated by the generated heat of polymerization, and a highly water-absorbent resin was obtained as a porous white solid with a very low water content.
実施例３
アクリル酸７０ｇを蒸留水２０ｇに溶解し、これに水酸
化カリウム４０．８ ｆｌを加えて、アクリル酸の７５
モル％を中和した。これにＮ、Ｎ−メチレノビスアクリ
ルアミドを０．００７１１加え、さらにメチルセルロー
スを２、Ｏｇ加えて攪拌して均一にした。次に開始剤と
して、２．２′−アゾビスイソブチロニトリル０７ｇを
溶解したアセトン溶液を１Ｑｃｃ加えた。この溶液を８
０℃の恒温水槽で加温された前述の箱型容器の中へ入れ
て加熱し、重合を開始させた。Example 3 70 g of acrylic acid was dissolved in 20 g of distilled water, and 40.8 fl of potassium hydroxide was added thereto to dissolve 75 g of acrylic acid.
Neutralized mole %. To this was added 0.00711 l of N,N-methylenebisacrylamide, and further added 20 g of methylcellulose and stirred to make it homogeneous. Next, 1 Qcc of an acetone solution containing 07 g of 2,2'-azobisisobutyronitrile was added as an initiator. Add this solution to 8
The mixture was placed in the aforementioned box-shaped container heated in a constant temperature water bath at 0° C. and heated to initiate polymerization.
重合反応が進み発生する重合熱によって水分が蒸発し、
含水率の非常に低い多孔性の白色固体として高吸水性樹
脂を得た。As the polymerization reaction progresses, water evaporates due to the polymerization heat generated.
A superabsorbent resin was obtained as a porous white solid with a very low water content.
比較例１
実施例１に於いてメチルセルロースを加えずにその他は
同様に重合し高吸水性樹脂を得た。Comparative Example 1 A superabsorbent resin was obtained by polymerizing in the same manner as in Example 1 except that methylcellulose was not added.
比較例２
実施例２に於いてメチルセルロースを加えずにその他は
同様に重合し、高吸水性樹脂を得た。Comparative Example 2 A superabsorbent resin was obtained by polymerizing in the same manner as in Example 2 except that methylcellulose was not added.
比較例３
実施例３に於いてメチルセルロースを加えずに、そノ他
は同様に重合し、高吸水性樹脂を得た。Comparative Example 3 Polymerization was carried out in the same manner as in Example 3 except that methylcellulose was not added to obtain a super absorbent resin.
実施例４
実施例１〜３及び比較例１〜３で得られた重合体を乾燥
工程を経ずに直接枠棒して粉末状の高吸水性樹脂を得た
。Example 4 The polymers obtained in Examples 1 to 3 and Comparative Examples 1 to 3 were directly molded into a frame without going through a drying process to obtain a powdery superabsorbent resin.
それぞれの粉末の吸水性能を見るために次の試験を行っ
た。The following test was conducted to examine the water absorption performance of each powder.
蒸留水２１に対して高吸水性樹脂の粉末（２０〜４０ｍ
ｅｓｈ）１１１を攪拌しながら加え、１時間放置した後
、１００ ｍｅｓｈのふるいを用いて沢過し、ｒ液量か
ら吸水量をＭ１定した。その結果は、吸水倍率（吸水量
÷加えた高吸水性樹脂の重Ｉｔ）によって表１に示した
。これより、本発明品は比較例に比べて著しく吸水性能
が優れていることが判明した。Powder of super absorbent resin (20-40 m
After adding esh) 111 with stirring and leaving it for 1 hour, it was filtered through a 100 mesh sieve, and the amount of water absorbed was determined as M1 from the amount of r liquid. The results are shown in Table 1 in terms of water absorption capacity (water absorption amount ÷ weight It of added super absorbent resin). From this, it was found that the product of the present invention had significantly superior water absorption performance compared to the comparative example.
表１ 吸水性能（吸水倍率）Table 1 Water absorption performance (water absorption capacity)
Claims (1)
００：０の範囲で、かつ、アクリル酸の７０モル％以上
がアンモニウム、アミン、又はアルカリ金属塩である単
量体（Ａ）と、アクリル−とアクリルアミド、１００重
量部に対して０゜００５〜０．０５重量部の水混和性乃
至水溶性ジビニル化合物（Ｂ）と、アクリル酸とアクリ
ルアミド１００重量部に対して０．５〜１０重量部のメ
チルセルロース′（Ｃ）を必須成分として水溶液重合を
行うことを特徴とする高吸水性樹脂の製造り法Acrylic acid and acrylamide in a molar ratio of 70:30 to 1
Monomer (A) in which 70 mol% or more of acrylic acid is ammonium, amine, or alkali metal salt, and acrylic and acrylamide, 0°005 to 0.005 to 100 parts by weight. Aqueous solution polymerization is carried out using as essential components 0.05 parts by weight of a water-miscible or water-soluble divinyl compound (B) and 0.5 to 10 parts by weight of methyl cellulose' (C) per 100 parts by weight of acrylic acid and acrylamide. A method for producing a super absorbent resin characterized by
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3591482A JPS58154708A (en) | 1982-03-09 | 1982-03-09 | Production of highly water-absorptive resin |
| US06/460,037 US4525527A (en) | 1982-01-25 | 1983-01-21 | Production process for highly water absorbable polymer |
| US06/710,702 US4612250A (en) | 1982-01-25 | 1985-03-11 | Production process for highly water absorbable polymer |
| US06/836,103 US4618631A (en) | 1982-01-25 | 1986-03-04 | Production process for highly water absorbable polymer |
| US07/389,616 US4985518A (en) | 1981-10-26 | 1989-08-04 | Process for preparing water-absorbing resins |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3591482A JPS58154708A (en) | 1982-03-09 | 1982-03-09 | Production of highly water-absorptive resin |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS58154708A true JPS58154708A (en) | 1983-09-14 |
Family
ID=12455293
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3591482A Pending JPS58154708A (en) | 1981-10-26 | 1982-03-09 | Production of highly water-absorptive resin |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58154708A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61166809A (en) * | 1985-01-19 | 1986-07-28 | Hayashikane Zosen Kk | Highly water-absorbing powder |
| JPS6222810A (en) * | 1985-07-22 | 1987-01-31 | Mitsubishi Petrochem Co Ltd | Production of water-absorptive composite |
| JPS6222811A (en) * | 1985-07-22 | 1987-01-31 | Mitsubishi Petrochem Co Ltd | Production of water-absorptive composite |
| JPS6253309A (en) * | 1985-09-02 | 1987-03-09 | Mitsubishi Petrochem Co Ltd | Production of water-absorbing composite material |
| JPS63178115A (en) * | 1986-09-12 | 1988-07-22 | Hayashikane Zosen Kk | Production of water-absorptive resin |
| US6586534B1 (en) * | 1994-10-04 | 2003-07-01 | Basf Aktiengesellschaft | Agglomerated particles of finely divided polymers which are water-soluble or capable of swelling in water and contain ammonium carboxylate groups |
| CN102432969A (en) * | 2011-08-29 | 2012-05-02 | 天津大学 | Variable-color and high-effective composite humidity controlling agent and its preparation method |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS51125468A (en) * | 1975-03-27 | 1976-11-01 | Sanyo Chem Ind Ltd | Method of preparing resins of high water absorbency |
| JPS54117734A (en) * | 1978-02-28 | 1979-09-12 | Sanyo Chemical Ind Ltd | Drying protecting agent of root |
-
1982
- 1982-03-09 JP JP3591482A patent/JPS58154708A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS51125468A (en) * | 1975-03-27 | 1976-11-01 | Sanyo Chem Ind Ltd | Method of preparing resins of high water absorbency |
| JPS54117734A (en) * | 1978-02-28 | 1979-09-12 | Sanyo Chemical Ind Ltd | Drying protecting agent of root |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61166809A (en) * | 1985-01-19 | 1986-07-28 | Hayashikane Zosen Kk | Highly water-absorbing powder |
| JPH0414684B2 (en) * | 1985-01-19 | 1992-03-13 | Taiyo Fishery Co Ltd | |
| JPS6222810A (en) * | 1985-07-22 | 1987-01-31 | Mitsubishi Petrochem Co Ltd | Production of water-absorptive composite |
| JPS6222811A (en) * | 1985-07-22 | 1987-01-31 | Mitsubishi Petrochem Co Ltd | Production of water-absorptive composite |
| JPS6253309A (en) * | 1985-09-02 | 1987-03-09 | Mitsubishi Petrochem Co Ltd | Production of water-absorbing composite material |
| JPS63178115A (en) * | 1986-09-12 | 1988-07-22 | Hayashikane Zosen Kk | Production of water-absorptive resin |
| US6586534B1 (en) * | 1994-10-04 | 2003-07-01 | Basf Aktiengesellschaft | Agglomerated particles of finely divided polymers which are water-soluble or capable of swelling in water and contain ammonium carboxylate groups |
| CN102432969A (en) * | 2011-08-29 | 2012-05-02 | 天津大学 | Variable-color and high-effective composite humidity controlling agent and its preparation method |
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