TW202035465A - Process for producing superabsorbent particles - Google Patents

Process for producing superabsorbent particles Download PDF

Info

Publication number
TW202035465A
TW202035465A TW109102371A TW109102371A TW202035465A TW 202035465 A TW202035465 A TW 202035465A TW 109102371 A TW109102371 A TW 109102371A TW 109102371 A TW109102371 A TW 109102371A TW 202035465 A TW202035465 A TW 202035465A
Authority
TW
Taiwan
Prior art keywords
roller
diameter
drum
polymer gel
conveyor belt
Prior art date
Application number
TW109102371A
Other languages
Chinese (zh)
Inventor
瑞恩 卡洛特
卡爾 波塞米爾
魯迪格 方克
馬可 克魯傑爾
瑪夏斯 威斯曼特爾
喬根 史羅德
Original Assignee
德商巴地斯顏料化工廠
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by 德商巴地斯顏料化工廠 filed Critical 德商巴地斯顏料化工廠
Publication of TW202035465A publication Critical patent/TW202035465A/en

Links

Images

Classifications

    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08FMACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F6/00Post-polymerisation treatments
    • C08F6/008Treatment of solid polymer wetted by water or organic solvents, e.g. coagulum, filter cakes
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C41/00Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
    • B29C41/24Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of indefinite length
    • B29C41/28Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of indefinite length by depositing flowable material on an endless belt
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C41/00Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
    • B29C41/34Component parts, details or accessories; Auxiliary operations
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26DRYING
    • F26BDRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B17/00Machines or apparatus for drying materials in loose, plastic, or fluidised form, e.g. granules, staple fibres, with progressive movement
    • F26B17/02Machines or apparatus for drying materials in loose, plastic, or fluidised form, e.g. granules, staple fibres, with progressive movement with movement performed by belts carrying the materials; with movement performed by belts or elements attached to endless belts or chains propelling the materials over stationary surfaces
    • F26B17/04Machines or apparatus for drying materials in loose, plastic, or fluidised form, e.g. granules, staple fibres, with progressive movement with movement performed by belts carrying the materials; with movement performed by belts or elements attached to endless belts or chains propelling the materials over stationary surfaces the belts being all horizontal or slightly inclined

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • General Engineering & Computer Science (AREA)
  • Processes Of Treating Macromolecular Substances (AREA)
  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)

Abstract

A process for producing superabsorbent particles by polymerizing a monomer solution or suspension, comprising drying of the resultant aqueous polymer gel in an air circulation belt drier, grinding, classifying, and optionally thermal surface postcrosslinking, wherein the aqueous polymer gel is introduced into the air circulation belt drier by means of an oscillating conveyor belt, the conveyor belt is run over a drive drum and a deflection drum, and the diameter in the middle of at least one of the drums is at least 1% greater than at the edges of the drum.

Description

製備超吸收性顆粒之方法Method for preparing superabsorbent particles

本發明係關於一種藉由聚合單體溶液或懸浮液來製備超吸收性顆粒之方法,其包含對空氣循環帶式乾燥器中之所得水性聚合物凝膠進行乾燥、研磨、分類且視情況熱表面後交聯,其中該水性聚合物凝膠藉助於振盪傳送帶引入至該空氣循環帶式乾燥器中,該傳送帶在驅動滾筒及偏轉滾筒上運行,且該等滾筒中之至少一者之中部直徑比該滾筒之邊緣處大至少1%。The present invention relates to a method for preparing superabsorbent particles by polymerizing a monomer solution or suspension, which comprises drying, grinding, sorting, and optionally heating the obtained aqueous polymer gel in an air circulating belt dryer. The surface is post-crosslinked, wherein the aqueous polymer gel is introduced into the air circulating belt dryer by means of an oscillating conveyor belt, which runs on a driving drum and a deflecting drum, and the middle diameter of at least one of the drums It is at least 1% larger than the edge of the drum.

超吸收劑用於製備尿布、棉塞、衛生棉及其他衛生用品,且亦用作市場園藝中之保水劑。超吸收劑亦被稱作吸水性聚合物。Superabsorbents are used to prepare diapers, tampons, sanitary napkins and other sanitary products, and are also used as water retention agents in market gardening. Superabsorbents are also called water-absorbing polymers.

超吸收劑之製備描述於專題著作「現代超吸收性聚合物技術(Modern Superabsorbent Polymer Technology)」, F. L. Buchholz及A. T. Graham, Wiley-VCH, 1998, 第71至103頁中。The preparation of superabsorbents is described in the monograph "Modern Superabsorbent Polymer Technology", F. L. Buchholz and A. T. Graham, Wiley-VCH, 1998, pages 71 to 103.

為改良效能特性,例如在49.2 g/cm² (AUL0.7psi)之壓力下之凝膠床滲透性(gel bed permeability;GBP)及吸收,超吸收性顆粒通常經表面後交聯。此增大顆粒表面之交聯水準,從而可至少部分地解耦在49.2 g/cm² (AUL0.7psi)之壓力下之吸收及離心保留容量(centrifuge retention capacity;CRC)。可在水性凝膠相中執行此表面後交聯。然而,較佳地,乾燥、研磨及篩分之聚合物顆粒(基質聚合物)用表面後交聯劑表面塗佈且經熱表面後交聯。適用於彼目的之交聯劑為可與聚合物顆粒之至少兩個羧酸根基團形成共價鍵之化合物。To improve performance characteristics, such as gel bed permeability (GBP) and absorption under a pressure of 49.2 g/cm² (AUL0.7psi), superabsorbent particles are usually post-crosslinked through the surface. This increases the level of cross-linking on the particle surface, which can at least partially decouple the absorption and centrifuge retention capacity (CRC) under a pressure of 49.2 g/cm² (AUL0.7psi). This surface post-crosslinking can be performed in the aqueous gel phase. However, preferably, the dried, ground, and sieved polymer particles (matrix polymer) are surface-coated with a surface post-crosslinking agent and cross-linked after the hot surface. Crosslinking agents suitable for this purpose are compounds that can form covalent bonds with at least two carboxylate groups of the polymer particles.

WO 2008/087114 A1、WO 2010/139680 A2及EP 2 700 667 A1描述藉助於振盪傳送帶使空氣循環帶式乾燥器之輸送帶裝載有水性聚合物凝膠。WO 2008/087114 A1, WO 2010/139680 A2 and EP 2 700 667 A1 describe that the conveyor belt of an air circulating belt dryer is loaded with an aqueous polymer gel by means of an oscillating conveyor belt.

本發明之一目的為提供一種用於製備超吸收劑,尤其所使用之傳送帶之經延長壽命的改良方法。One of the objects of the present invention is to provide an improved method for preparing superabsorbents, especially for the extended life of the conveyor belts used.

目的係利用藉由聚合包含以下之單體溶液或懸浮液來製備超吸收劑之方法來達成: a)     至少一種烯系不飽和單體,其攜帶酸基且至少經部分中和, b)     至少一種交聯劑及 c)     至少一種引發劑, 該方法包含對空氣循環帶式乾燥器中之所得水性聚合物凝膠進行乾燥、研磨、分類且視情況熱表面後交聯,其中該水性聚合物凝膠藉助於振盪傳送帶引入至該空氣循環帶式乾燥器中,該傳送帶在驅動滾筒及偏轉滾筒上運行,且該等滾筒中之至少一者之中部直徑比該滾筒之邊緣處大至少1%。The purpose is to use a method of preparing a superabsorbent by polymerizing a monomer solution or suspension containing the following: a) At least one ethylenically unsaturated monomer, which carries an acid group and is at least partially neutralized, b) At least one crosslinking agent and c) At least one initiator, The method includes drying, grinding, sorting and optionally heating the surface and crosslinking the obtained aqueous polymer gel in an air circulating belt dryer, wherein the aqueous polymer gel is introduced into the air circulating belt by means of an oscillating conveyor belt In a type dryer, the conveyor belt runs on a driving roller and a deflecting roller, and the diameter of at least one of the rollers is at least 1% larger than the edge of the roller.

振盪傳送帶為以豎直軸線可週期性地樞轉之傳送帶。振盪傳送帶之傳送帶自身基本上以恆定速度運行。振盪傳送帶之傳送帶具有比空氣循環帶式乾燥器之傳送帶明顯較小之寬度。振盪傳送帶之週期性樞轉運動導致在總寬度內空氣循環帶式乾燥器之傳送帶均勻覆蓋有聚合物凝膠。The oscillating conveyor belt is a conveyor belt that can be pivoted periodically with a vertical axis. The conveyor belt itself basically runs at a constant speed. The conveyor belt of the oscillating conveyor belt has a significantly smaller width than the conveyor belt of the air circulating belt dryer. The periodic pivoting movement of the oscillating conveyor belt causes the conveyor belt of the air circulating belt dryer to be uniformly covered with polymer gel in the total width.

滾筒之運行表面為滾筒表面減去端面。The running surface of the drum is the drum surface minus the end surface.

在本發明之一較佳實施例中,驅動滾筒之中部直徑比驅動滾筒之邊緣處大至少1%。In a preferred embodiment of the present invention, the diameter of the middle part of the driving drum is at least 1% larger than the edge of the driving drum.

在本發明之一極佳實施例中,驅動滾筒之中部及偏轉滾筒之中部的直徑比驅動滾筒及偏轉滾筒之邊緣處大至少1%。In an excellent embodiment of the present invention, the diameter of the middle part of the driving roller and the middle part of the deflection roller is at least 1% larger than the edge of the driving roller and the deflection roller.

滾筒中之至少一者之中部直徑比滾筒之邊緣處大較佳2%至8%,更佳地2.5%至6%,最佳地3%至5%。直徑在各情況下為滾筒之外徑。The middle diameter of at least one of the rollers is preferably 2% to 8% larger than the edge of the roller, more preferably 2.5% to 6%, most preferably 3% to 5%. The diameter is the outer diameter of the drum in each case.

至少一個滾筒之中間區域可具有恆定直徑。中間區域較佳地佔滾筒之總長度之20%至80%,更佳地30%至70%,最佳地40%至60%。The middle area of at least one drum may have a constant diameter. The middle area preferably occupies 20% to 80% of the total length of the drum, more preferably 30% to 70%, and most preferably 40% to 60%.

針對具有1000 mm之長度之滾筒,其直徑自各別端沿滾筒的中部方向上升250 mm之長度且隨後保持與滾筒中部的恆定距離,中間區域為滾筒之總長度之50%。For a roller with a length of 1000 mm, its diameter rises from the respective ends by 250 mm in the direction of the middle of the roller and then maintains a constant distance from the middle of the roller. The middle area is 50% of the total length of the roller.

圖1展示本發明之滾筒(1)之縱向截面。Figure 1 shows a longitudinal section of the drum (1) of the present invention.

本發明係基於在使用本發明之滾筒時可延長傳送帶之壽命的發現。The present invention is based on the discovery that the life of the conveyor belt can be extended when the roller of the present invention is used.

滾筒具有較佳地50至500 mm、更佳地100至400 mm、最佳地150至300 mm之直徑。滾筒具有較佳地500至1400 mm、更佳地600至1200 mm、最佳地700至1000 mm之長度。The drum has a diameter of preferably 50 to 500 mm, more preferably 100 to 400 mm, and most preferably 150 to 300 mm. The roller has a length of preferably 500 to 1400 mm, more preferably 600 to 1200 mm, and most preferably 700 to 1000 mm.

滾筒中之至少一者之運行表面可具有孔口。孔口比率較佳為10%至70%,更佳地15%至60%,最佳地20%至50%。孔口比率為運行表面中之所有孔口之面積總和與不包括孔口之總運行表面積之商。孔口面積假定為平面以用於計算。在具有可變面積之孔口,例如圓錐形孔的情況下,在各情況下假定最小面積以用於計算。假定滾筒為圓柱體以用於計算,圓柱體直徑為滾筒之最大直徑。The running surface of at least one of the drums may have apertures. The orifice ratio is preferably 10% to 70%, more preferably 15% to 60%, most preferably 20% to 50%. The orifice ratio is the quotient of the sum of the area of all orifices in the running surface and the total running surface area excluding the orifices. The orifice area is assumed to be flat for calculation. In the case of an orifice with a variable area, such as a conical hole, a minimum area is assumed for calculation in each case. Assuming that the drum is a cylinder for calculation, the diameter of the cylinder is the maximum diameter of the drum.

運行表面中之孔口形狀不經受任何限制。適合之孔口為例如柵格、孔洞或狹槽。The shape of the orifice in the running surface is not subject to any restrictions. Suitable apertures are, for example, grids, holes or slots.

運行表面中之孔洞在下文中稱作孔洞1。The hole in the running surface is referred to as hole 1 in the following.

針對具有200 mm之直徑d及1000 mm之長度l的圓柱形滾筒,結果為不包括之孔口之總運行表面積π. d. l=0.6283 m²。For a cylindrical drum having a length l of 200 mm and 1000 mm of diameter d, the result is a total surface area of the run of π does not include the aperture. D. L = 0.6283 m².

針對640個具有25 mm之直徑d之孔洞1,發現運行表面中之所有孔口之面積總和為640. π. (d/2)2 =0.3142 m²。對於此實例,此產生0.3142 m²/0.6283 m²=50%之孔口比率。For 640 holes having a 25 mm of diameter d 1, was found in the total area of the running surface of all the apertures 640. Π. (D / 2 ) 2 = 0.3142 m². For this example, this yields an orifice ratio of 0.3142 m²/0.6283 m²=50%.

針對15個具有20 mm之最小間距b及1000 mm之長度l的棒,發現運行表面中之所有孔口之面積總和為15. b. l=0.3000 m²。對於此實例,此產生0.3000 m²/0.6283 m²=48%之孔口比率。For rod 15 having a minimum pitch of 20 mm and a length l b of 1000 mm, the total area of all the orifices found in the running of the surface is 15. B. L = 0.3000 m² . For this example, this yields an orifice ratio of 0.3000 m²/0.6283 m²=48%.

具有孔洞1之運行表面可藉由例如在運行表面中鑽出具有所需直徑之孔洞1來產生。孔洞1之直徑較佳為10至50 mm,更佳地15至40 mm,最佳地20至30 mm。孔洞1通常均勻分佈於運行表面上。The running surface with holes 1 can be produced by, for example, drilling holes 1 of the required diameter in the running surface. The diameter of the hole 1 is preferably 10 to 50 mm, more preferably 15 to 40 mm, and most preferably 20 to 30 mm. The holes 1 are usually evenly distributed on the running surface.

具有狹槽之運行表面可由例如葉輪(2)及棒(3)形成。圖2及3展示由葉輪(2)及棒(3)形成之棒狀滾筒。棒(3)之間的最小距離較佳為4至30 mm,更佳地6至20 mm,最佳地8至12 mm。棒(3)較佳地均勻分佈於葉輪(2)上。The running surface with slots can be formed by, for example, an impeller (2) and a rod (3). Figures 2 and 3 show the rod-shaped drum formed by the impeller (2) and the rod (3). The minimum distance between the rods (3) is preferably 4 to 30 mm, more preferably 6 to 20 mm, most preferably 8 to 12 mm. The rods (3) are preferably evenly distributed on the impeller (2).

聚合物凝膠可進入傳送帶下方。此聚合物凝膠隨後進入驅動滾筒或偏轉滾筒之運行表面上。聚合物凝膠導致運行表面上之帶未對準,意謂滾筒上之循環傳送帶移動至側面。此外,驅動滾筒之運行表面上之聚合物凝膠導致滾筒之滑脫,亦即導致驅動功率降低。聚合物凝膠可經由運行表面中之孔口進入滾筒之內部中,且因此自運行表面移除。因此防止帶未對準及驅動滾筒之滑脫。The polymer gel can enter under the conveyor belt. This polymer gel then enters the running surface of the driving drum or the deflection drum. The polymer gel causes the belt on the running surface to be misaligned, meaning that the endless conveyor belt on the drum moves to the side. In addition, the polymer gel on the running surface of the driving drum causes the slippage of the drum, that is, the driving power is reduced. The polymer gel can enter the interior of the drum through the orifices in the running surface and is therefore removed from the running surface. This prevents belt misalignment and slippage of the drive roller.

至少一個滾筒可在端面中具有其他孔口。端面中之孔口形狀不經受任何限制。適合之孔口為例如凹槽或孔洞。At least one drum may have other apertures in the end surface. The shape of the orifice in the end face is not subject to any restrictions. Suitable openings are, for example, grooves or holes.

端面中之孔洞在下文中稱作孔洞2。The hole in the end face is called hole 2 hereinafter.

適合之實例為運行表面中具有孔洞1,以及端面中之其他孔口呈鄰接滾筒表面之凹槽形式的滾筒。此類滾筒之端面可採用例如六角星之形式。A suitable example is a drum with holes 1 in the running surface and other openings in the end surface in the form of grooves adjacent to the drum surface. The end surface of this type of roller can take the form of a six-pointed star, for example.

另一適合實例為由葉輪(2)及棒(3)組成之棒狀滾筒,其中端面中之其他孔口為葉輪(2)中之孔洞2。此棒狀滾筒由圖2及3展示。孔洞2之直徑較佳為10至50 mm,更佳地15至35 mm,最佳地20至40 mm。孔洞2通常均勻分佈於葉輪(2)上。Another suitable example is a rod-shaped drum composed of an impeller (2) and a rod (3), wherein the other orifices in the end surface are the holes 2 in the impeller (2). This rod-shaped roller is shown in Figures 2 and 3. The diameter of the hole 2 is preferably 10 to 50 mm, more preferably 15 to 35 mm, and most preferably 20 to 40 mm. The holes 2 are usually evenly distributed on the impeller (2).

經由端面中之其他孔口,有可能使存在於滾筒內部中之聚合物凝膠在側面處離開滾筒之內部。此可額外藉由吹出,例如藉助於壓縮空氣來輔助。Through other openings in the end surface, it is possible to cause the polymer gel existing in the inside of the drum to leave the inside of the drum at the side. This can additionally be assisted by blowing, for example by means of compressed air.

傳送帶具有較佳地2至10 m、更佳地2.5至8 m、最佳地3至6 m之長度,其中傳送帶之長度為樞轉軸與排出端之距離。The conveyor belt has a length of preferably 2 to 10 m, more preferably 2.5 to 8 m, and most preferably 3 to 6 m, wherein the length of the conveyor belt is the distance between the pivot axis and the discharge end.

傳送帶具有較佳地0.5至1.5 m、更佳地0.6至1.2 m、最佳地0.7至0.9 m之寬度。The conveyor belt has a width of preferably 0.5 to 1.5 m, more preferably 0.6 to 1.2 m, and most preferably 0.7 to 0.9 m.

傳送帶速度較佳為0.2至2.0 m/s,更佳地0.3至1.5 m/s,最佳地0.4至1.0 m/s。The speed of the conveyor belt is preferably 0.2 to 2.0 m/s, more preferably 0.3 to 1.5 m/s, most preferably 0.4 to 1.0 m/s.

出於此目的,有可能使用習用之傳送帶。傳送帶之表面(亦即與聚合物凝膠發生接觸之側面)應為防水的,且在23℃下具有較佳地至少60°、更佳地至少80°、最佳地至少100°的相對於水之接觸角。接觸角為潤濕行為之量測值且根據DIN 53900量測。For this purpose, it is possible to use conventional conveyor belts. The surface of the conveyor belt (that is, the side that comes into contact with the polymer gel) should be waterproof, and have a relative value of at least 60°, more preferably at least 80°, and most preferably at least 100° at 23°C. The contact angle of water. The contact angle is a measure of the wetting behavior and is measured according to DIN 53900.

傳送帶上之聚合物凝膠之含水量較佳為20至80重量%,更佳地30至70重量%,最佳地40至60重量%。The water content of the polymer gel on the conveyor belt is preferably 20 to 80% by weight, more preferably 30 to 70% by weight, and most preferably 40 to 60% by weight.

傳送帶上之聚合物凝膠之溫度較佳為60℃至105℃,更佳地70℃至100℃且最佳地80℃至95℃。The temperature of the polymer gel on the conveyor belt is preferably 60°C to 105°C, more preferably 70°C to 100°C, and most preferably 80°C to 95°C.

超吸收劑之製備詳細描述於下文中: 超吸收劑藉由聚合單體溶液或懸浮液來製備,且通常為不溶於水的。The preparation of superabsorbent is described in detail below: Superabsorbents are prepared by polymerizing monomer solutions or suspensions, and are generally insoluble in water.

單體a)較佳為水溶性的,亦即其於水中之溶解度在23℃下通常為至少1 g/100 g水,較佳地至少5 g/100 g水,更佳地至少25 g/100 g水且最佳地至少35 g/100 g水。Monomer a) is preferably water-soluble, that is, its solubility in water at 23°C is usually at least 1 g/100 g of water, preferably at least 5 g/100 g of water, more preferably at least 25 g/ 100 g water and optimally at least 35 g/100 g water.

適合之單體a)為例如烯系不飽和羧酸,諸如丙烯酸、甲基丙烯酸及伊康酸(itaconic acid)。尤佳單體為丙烯酸及甲基丙烯酸。極其較佳為丙烯酸。Suitable monomers a) are, for example, ethylenically unsaturated carboxylic acids, such as acrylic acid, methacrylic acid and itaconic acid. Particularly preferred monomers are acrylic acid and methacrylic acid. Very preferred is acrylic acid.

單體a)通常包含作為儲存穩定劑之聚合抑制劑,較佳地氫醌單醚。Monomer a) usually contains a polymerization inhibitor as a storage stabilizer, preferably hydroquinone monoether.

適合之交聯劑b)為具有適用於交聯之至少兩個基團之化合物。此類基團為例如可自由基聚合至聚合物鏈中之烯系不飽和基團及可與單體a)之酸基形成共價鍵之官能基。另外,可與單體a)之至少兩個酸基形成配位鍵之多價金屬鹽亦適用作交聯劑b)。Suitable crosslinking agents b) are compounds having at least two groups suitable for crosslinking. Such groups are, for example, ethylenically unsaturated groups that can be free-radically polymerized into the polymer chain and functional groups that can form covalent bonds with the acid groups of monomer a). In addition, polyvalent metal salts that can form coordinate bonds with at least two acid groups of monomer a) are also suitable as crosslinking agents b).

交聯劑b)較佳為具有可自由基聚合至聚合物網路中之至少兩個可聚合基團的化合物。適合之交聯劑b)為例如乙二醇二甲基丙烯酸酯、二乙二醇二丙烯酸酯、聚乙二醇二丙烯酸酯、甲基丙烯酸烯丙酯、三羥甲基丙烷三丙烯酸酯、三烯丙基胺、氯化四烯丙銨、四烯丙氧基乙烷,如EP 0 530 438 A1中所描述;二丙烯酸酯及三丙烯酸酯(如EP 0 547 847 A1、EP 0 559 476 A1、EP 0 632 068 A1、WO 93/21237 A1、WO 03/104299 A1、WO 03/104300 A1、WO 03/104301 A1及DE 103 31 450 A1中所描述)、其混合丙烯酸酯;以及丙烯酸酯基;包含其他烯系不飽和基團(如DE 103 31 456 A1及DE 103 55 401 A1中所描述);或交聯劑混合物,如例如DE 195 43 368 A1、DE 196 46 484 A1、WO 90/15830 A1及WO 02/032962 A2中所描述。The crosslinking agent b) is preferably a compound having at least two polymerizable groups that can be free-radically polymerized into the polymer network. Suitable crosslinking agents b) are, for example, ethylene glycol dimethacrylate, diethylene glycol diacrylate, polyethylene glycol diacrylate, allyl methacrylate, trimethylolpropane triacrylate, Triallylamine, tetraallylammonium chloride, tetraallyloxyethane, as described in EP 0 530 438 A1; diacrylate and triacrylate (such as EP 0 547 847 A1, EP 0 559 476 A1, EP 0 632 068 A1, WO 93/21237 A1, WO 03/104299 A1, WO 03/104300 A1, WO 03/104301 A1 and DE 103 31 450 A1), mixed acrylates thereof; and acrylates Group; containing other ethylenically unsaturated groups (as described in DE 103 31 456 A1 and DE 103 55 401 A1); or crosslinking agent mixtures, such as, for example, DE 195 43 368 A1, DE 196 46 484 A1, WO 90 /15830 A1 and WO 02/032962 A2.

交聯劑b)之量較佳為0.05重量%至1.5重量%,更佳地0.1重量%至1重量%且最佳地0.3重量%至0.6重量% (在各情況下基於所使用之單體a)之總量來計算)。隨著交聯劑含量上升,離心保留容量(CRC)下降且在21.0 g/cm² (AUL0.3psi)之壓力下之吸收達至最大值。The amount of crosslinking agent b) is preferably 0.05% to 1.5% by weight, more preferably 0.1% to 1% by weight, and most preferably 0.3% to 0.6% by weight (in each case based on the monomer used a) to calculate the total amount). As the content of crosslinking agent increases, the centrifuge retention capacity (CRC) decreases and the absorption reaches its maximum value under a pressure of 21.0 g/cm² (AUL0.3psi).

所使用之引發劑c)可為在聚合條件下產生自由基之所有化合物,例如熱引發劑、氧化還原引發劑或光引發劑。適合之氧化還原引發劑為過硫酸鈉/抗壞血酸、過氧化氫/抗壞血酸、過硫酸鈉/亞硫酸氫鈉及過氧化氫/亞硫酸氫鈉。較佳為使用熱引發劑及氧化還原引發劑之混合物,諸如過硫酸鈉/過氧化氫/抗壞血酸。所使用之還原組分較佳為2-羥基-2-磺酸基乙酸之二鈉鹽或2-羥基-2-亞磺酸基乙酸之鈉鹽、2-羥基-2-磺酸基乙酸之二鈉鹽及亞硫酸氫鈉的混合物。此類混合物可以Brüggolite® FF6及Brüggolite® FF7 (Brüggemann Chemicals;Heilbronn;德國)形式獲得。The initiator c) used can be all compounds that generate free radicals under polymerization conditions, such as thermal initiators, redox initiators or photoinitiators. Suitable redox initiators are sodium persulfate/ascorbic acid, hydrogen peroxide/ascorbic acid, sodium persulfate/sodium bisulfite and hydrogen peroxide/sodium bisulfite. It is preferable to use a mixture of a thermal initiator and a redox initiator, such as sodium persulfate/hydrogen peroxide/ascorbic acid. The reducing component used is preferably the disodium salt of 2-hydroxy-2-sulfoacetic acid or the sodium salt of 2-hydroxy-2-sulfinoacetic acid, or the sodium salt of 2-hydroxy-2-sulfoacetic acid. A mixture of disodium salt and sodium bisulfite. Such mixtures are available in the form of Brüggolite® FF6 and Brüggolite® FF7 (Brüggemann Chemicals; Heilbronn; Germany).

通常,使用單體水溶液。單體溶液之含水量較佳為40重量%至75重量%,更佳地45重量%至70重量%且最佳地50重量%至65重量%。亦有可能使用單體懸浮液,亦即溶解度超過單體a)之單體溶液,例如丙烯酸鈉。當含水量上升時,後續乾燥中之能量消耗上升,且當含水量下降時,僅可不充分地移除聚合熱。Generally, an aqueous monomer solution is used. The water content of the monomer solution is preferably 40% to 75% by weight, more preferably 45% to 70% by weight, and most preferably 50% to 65% by weight. It is also possible to use monomer suspensions, that is, monomer solutions with a solubility exceeding monomer a), such as sodium acrylate. When the water content increases, the energy consumption in the subsequent drying increases, and when the water content decreases, the heat of polymerization can only be insufficiently removed.

對於最佳作用,較佳的聚合抑制劑需要溶解氧。因此,單體溶液可在聚合之前藉由惰性化,亦即使惰性氣體(較佳地氮氣或二氧化碳)流過來釋放溶解氧。單體溶液之氧含量在聚合之前較佳地下降至小於1重量ppm,更佳地小於0.5重量ppm,最佳地小於0.1重量ppm。For optimal effect, the preferred polymerization inhibitors require dissolved oxygen. Therefore, the monomer solution can be inertized before polymerization, even if an inert gas (preferably nitrogen or carbon dioxide) flows over to release dissolved oxygen. The oxygen content of the monomer solution is preferably reduced to less than 1 ppm by weight before polymerization, more preferably less than 0.5 ppm by weight, and most preferably less than 0.1 ppm by weight.

用於聚合之適合反應器為例如捏合反應器或帶式反應器。如WO 2001/038402 A1中所描述,在捏合機中,單體水溶液或懸浮液之聚合中所形成之聚合物凝膠藉由例如反向旋轉攪拌器軸(contrarotatory stirrer shaft)連續地粉碎。帶上之聚合描述於例如DE 38 25 366 A1及US 6,241,928中。帶式反應器中之聚合形成必須在例如擠壓機或捏合機中粉碎之聚合物凝膠。Suitable reactors for polymerization are, for example, kneading reactors or belt reactors. As described in WO 2001/038402 A1, in the kneader, the polymer gel formed in the polymerization of the monomer aqueous solution or suspension is continuously pulverized by, for example, a contrarotatory stirrer shaft. Polymerization on the tape is described in, for example, DE 38 25 366 A1 and US 6,241,928. Polymerization in a belt reactor forms a polymer gel that must be comminuted in, for example, an extruder or kneader.

為改良乾燥特性,可額外擠壓藉助於捏合機獲得之經粉碎聚合物凝膠。In order to improve the drying characteristics, the pulverized polymer gel obtained by means of a kneader can be additionally extruded.

所得聚合物凝膠之酸基通常經部分中和。較佳地在單體階段實行中和。此通常藉由混合呈水溶液形式或另外較佳地呈固體形式之中和劑來實行。中和度較佳為40至85 mol%,更佳地50至80 mol%且最佳地60至75 mol%,其中可使用習用中和劑,較佳地鹼金屬氫氧化物、鹼金屬氧化物、鹼金屬碳酸鹽或鹼金屬碳酸氫鹽以及其混合物。亦有可能使用銨鹽而非鹼金屬鹽。尤佳的鹼金屬為鈉及鉀,但極其較佳為氫氧化鈉、碳酸鈉或碳酸氫鈉以及其混合物。固態碳酸鹽及碳酸氫鹽亦可以囊封形式引入於此,較佳地在聚合之前直接地引入至單體溶液中,在聚合期間或之後且在其乾燥之前引入至聚合物凝膠中。囊封藉由用不溶或僅逐漸溶解之材料塗佈表面(例如,藉助於成膜聚合物、惰性無機材料或可熔性有機材料)來實現,該材料將固態碳酸鹽或碳酸氫鹽之溶解及反應延遲至不釋放二氧化碳之此類程度直至乾燥過程為止,且所形成之超吸收劑具有較高內部孔隙率。The acid groups of the resulting polymer gel are usually partially neutralized. The neutralization is preferably carried out in the monomer stage. This is usually carried out by mixing the neutralizing agent in the form of an aqueous solution or otherwise preferably in the form of a solid. The degree of neutralization is preferably 40 to 85 mol%, more preferably 50 to 80 mol% and most preferably 60 to 75 mol%. Among them, conventional neutralizing agents can be used, preferably alkali metal hydroxides, alkali metal oxidation , Alkali metal carbonate or alkali metal bicarbonate and mixtures thereof. It is also possible to use ammonium salts instead of alkali metal salts. Particularly preferred alkali metals are sodium and potassium, but extremely preferred are sodium hydroxide, sodium carbonate or sodium bicarbonate and mixtures thereof. Solid carbonate and bicarbonate can also be introduced here in encapsulated form, preferably directly into the monomer solution before polymerization, and into the polymer gel during or after polymerization and before drying. Encapsulation is achieved by coating the surface with an insoluble or only gradually dissolving material (for example, with the aid of film-forming polymers, inert inorganic materials or fusible organic materials) that dissolves solid carbonate or bicarbonate And the reaction is delayed to such an extent that no carbon dioxide is released until the drying process, and the superabsorbent formed has a higher internal porosity.

聚合物凝膠隨後通常經空氣循環帶式乾燥器乾燥直至殘餘水分含量較佳為0.5至10重量%,更佳地1至7重量%且最佳地2至5重量%為止,殘餘水分含量藉由EDANA建議之測試方法第WSP 230.2-05號「加熱後之質量損失(Mass Loss Upon Heating)」來測定。在殘餘水分含量太高之情況下,經乾燥之聚合物凝膠具有太低之玻璃轉變溫度Tg 且僅可困難地進一步處理。在殘餘水分含量太低之情況下,經乾燥之聚合物凝膠太脆,且在後續粉碎步驟中,獲得不合需要地大量具有過低粒度之聚合物顆粒(「細粒」)。在乾燥之前聚合物凝膠之固體含量較佳為25重量%至90重量%,更佳地35重量%至70重量%,最佳地40重量%至60重量%。隨後,經乾燥之聚合物凝膠經壓碎且視情況粗略地粉碎。The polymer gel is then usually dried by an air circulating belt dryer until the residual moisture content is preferably 0.5 to 10% by weight, more preferably 1 to 7% by weight, and most preferably 2 to 5% by weight, the residual moisture content is determined by It is determined by the test method No. WSP 230.2-05 "Mass Loss Upon Heating" recommended by EDANA. In the case of too high residual moisture content, the dried polymer gel has a glass transition temperature T g that is too low and can only be processed further with difficulty. In the case where the residual moisture content is too low, the dried polymer gel is too brittle, and in the subsequent pulverization step, an undesirably large amount of polymer particles ("fine particles") with too low particle size are obtained. The solid content of the polymer gel before drying is preferably 25% to 90% by weight, more preferably 35% to 70% by weight, most preferably 40% to 60% by weight. Subsequently, the dried polymer gel is crushed and roughly pulverized as appropriate.

其後,通常對經乾燥之聚合物凝膠進行研磨及分類,且用於研磨之裝置可通常為單級或多級輥磨機,較佳地二級或三級輥磨機、針磨機、錘磨機或振動球磨機。After that, the dried polymer gel is usually ground and classified, and the device for grinding can usually be a single-stage or multi-stage roller mill, preferably a two-stage or three-stage roller mill, a pin mill , Hammer mill or vibrating ball mill.

作為產物級分移除之聚合物顆粒之平均粒度較佳為150至850 µm,更佳地250至600 µm,極其特定地300至500 µm。產物級分之平均粒度可藉助於EDANA建議之測試方法第WSP 220.2 (05)號「粒度分佈(Particle Size Distribution)」來測定,其中以篩檢級分之質量計之比例以累積形式繪製且平均粒度以圖形方式判定。此處之平均粒度為產生累積50重量%之篩孔尺寸之值。The average particle size of the polymer particles removed as the product fraction is preferably 150 to 850 µm, more preferably 250 to 600 µm, and very specifically 300 to 500 µm. The average particle size of the product fraction can be determined by means of the test method No. WSP 220.2 (05) "Particle Size Distribution" recommended by EDANA, in which the ratio of the mass of the screening fraction is plotted in cumulative form and averaged The granularity is determined graphically. The average particle size here is the value of the mesh size that produces a cumulative 50% by weight.

為進一步改良特性,聚合物顆粒可經熱表面後交聯。適合之表面後交聯劑為包含可與聚合物顆粒之至少兩個羧酸根基團形成共價鍵的基團之化合物。適合之化合物為例如多官能胺,多官能醯胺基胺、多官能環氧化物,如EP 0 083 022 A2、EP 0 543 303 A1及EP 0 937 736 A2中所描述;二官能醇或多官能醇,如DE 33 14 019 A1、DE 35 23 617 A1及EP 0 450 922 A2中所描述;或β-羥烷基醯胺,如DE 102 04 938 A1及US 6,239,230中所描述。To further improve the properties, the polymer particles can be cross-linked after being heated to the surface. Suitable surface post-crosslinking agents are compounds containing groups that can form covalent bonds with at least two carboxylate groups of the polymer particles. Suitable compounds are, for example, polyfunctional amines, polyfunctional amidoamines, polyfunctional epoxides, as described in EP 0 083 022 A2, EP 0 543 303 A1 and EP 0 937 736 A2; difunctional alcohols or polyfunctional Alcohols, as described in DE 33 14 019 A1, DE 35 23 617 A1 and EP 0 450 922 A2; or β-hydroxyalkylamides, as described in DE 102 04 938 A1 and US 6,239,230.

在各情況下按聚合物顆粒計,表面後交聯劑之量較佳為0.001重量%至2重量%,更佳地0.02重量%至1重量%且最佳地0.05重量%至0.2重量%。In each case, based on the polymer particles, the amount of the surface post-crosslinking agent is preferably 0.001% to 2% by weight, more preferably 0.02% to 1% by weight, and most preferably 0.05% to 0.2% by weight.

在本發明之一較佳實施例中,除表面後交聯劑以外,將多價陽離子施用於顆粒表面。In a preferred embodiment of the present invention, in addition to the surface post-crosslinking agent, a multivalent cation is applied to the surface of the particle.

可用於本發明之方法中之多價陽離子為例如二價陽離子,諸如鋅、鎂、鈣及鍶之陽離子;三價陽離子,諸如鋁、鐵、鉻、稀土及錳之陽離子;四價陽離子,諸如鈦及鋯之陽離子。可能的相對離子為氯離子、溴離子、氫氧根、硫酸根、硫酸氫根、碳酸根、碳酸氫根、硝酸根、磷酸根、磷酸氫根、二氫磷酸根及羧酸根,諸如乙酸根及乳酸根。氫氧化鋁、硫酸鋁及乳酸鋁為較佳的。Multivalent cations that can be used in the method of the present invention are, for example, divalent cations, such as zinc, magnesium, calcium, and strontium; trivalent cations, such as aluminum, iron, chromium, rare earth and manganese cations; and tetravalent cations, such as Cation of titanium and zirconium. Possible counter ions are chloride, bromide, hydroxide, sulfate, hydrogen sulfate, carbonate, hydrogen carbonate, nitrate, phosphate, hydrogen phosphate, dihydrophosphate and carboxylate, such as acetate And lactate. Aluminum hydroxide, aluminum sulfate and aluminum lactate are preferred.

在各情況下按聚合物計,所使用之多價陽離子之量為例如0.001重量%至1.5重量%,較佳地0.005重量%至1重量%且更佳地0.02重量%至0.8重量%。In each case, based on the polymer, the amount of the polyvalent cation used is, for example, 0.001% to 1.5% by weight, preferably 0.005% to 1% by weight, and more preferably 0.02% to 0.8% by weight.

表面後交聯通常以將表面後交聯劑之溶液噴霧至經乾燥之聚合物顆粒上之此方式執行。在噴霧施加之後,塗佈有表面後交聯劑之聚合物顆粒經表面後交聯及乾燥,且可在乾燥之前及乾燥期間均發生表面後交聯反應。Surface post-crosslinking is usually performed by spraying a solution of the surface post-crosslinking agent onto the dried polymer particles. After spray application, the polymer particles coated with the surface post-crosslinking agent are surface post-crosslinked and dried, and the surface post-crosslinking reaction can occur before and during drying.

表面後交聯劑之溶液之噴霧施加較佳地於具有移動混合工具之混合器(諸如螺桿混合器、圓盤式混合器及槳葉式混合器)執行。尤其較佳為臥式混合器(諸如槳葉式混合器),極其較佳的為立式混合器。臥式混合器與立式混合器之間的區別在於混合軸之位置,亦即臥式混合器具有水平安裝之混合軸且立式混合器具有豎直安裝之混合軸。適合之混合器為例如臥式Pflugschar®犁鏵式混合器(plowshare mixer) (Gebr. Lödige Maschinenbau GmbH;Paderborn;德國)、Vrieco-Nauta連續混合器(Hosokawa Micron BV;Doetinchem;荷蘭)、Processall Mixmill混合器(Processall Incorporated;Cincinnati;美國)及Schugi Flexomix® (Hosokawa Micron BV;Doetinchem;荷蘭)。然而,亦有可能在流體化床中噴霧表面後交聯劑溶液。The spray application of the solution of the surface post-crosslinking agent is preferably performed in a mixer with a moving mixing tool (such as a screw mixer, a disc mixer, and a paddle mixer). Especially preferred is a horizontal mixer (such as a paddle mixer), and extremely preferred is a vertical mixer. The difference between the horizontal mixer and the vertical mixer is the position of the mixing shaft, that is, the horizontal mixer has a horizontally installed mixing shaft and the vertical mixer has a vertically installed mixing shaft. Suitable mixers are, for example, horizontal Pflugschar® plowshare mixer (Gebr. Lödige Maschinenbau GmbH; Paderborn; Germany), Vrieco-Nauta continuous mixer (Hosokawa Micron BV; Doetinchem; Netherlands), Processall Mixmill mixer (Processall Incorporated; Cincinnati; USA) and Schugi Flexomix® (Hosokawa Micron BV; Doetinchem; Netherlands). However, it is also possible to spray the surface post-crosslinker solution in a fluidized bed.

表面後交聯劑通常以水溶液之形式使用。表面後交聯劑至聚合物顆粒中之穿透深度(penetration depth)可經由非水性溶劑之含量及溶劑之總量來調整。The surface post-crosslinking agent is usually used in the form of an aqueous solution. The penetration depth of the surface post-crosslinking agent into the polymer particles can be adjusted by the content of the non-aqueous solvent and the total amount of the solvent.

表面後交聯較佳地於接觸式乾燥器、更佳地鏟式乾燥器、最佳地圓盤式乾燥器中執行。適合之乾燥器為例如Hosokawa Bepex®水平槳葉式乾燥器(Horizontal Paddle Dryer) (Hosokawa Micron GmbH;Leingarten;德國)、Hosokawa Bepex®碟式乾燥器(Hosokawa Micron GmbH;Leingarten;德國)、Holo-Flite®乾燥器(Metso Minerals Industries Inc.;Danville;美國)及Nara槳葉式乾燥器(NARA Machinery Europe;Frechen;德國)。此外,亦可使用流體化床乾燥器。Surface post-crosslinking is preferably performed in contact dryers, more preferably shovel dryers, and best disc dryers. Suitable dryers are, for example, Hosokawa Bepex® Horizontal Paddle Dryer (Hosokawa Micron GmbH; Leingarten; Germany), Hosokawa Bepex® Dish Dryer (Hosokawa Micron GmbH; Leingarten; Germany), Holo-Flite ® Dryer (Metso Minerals Industries Inc.; Danville; USA) and Nara paddle dryer (NARA Machinery Europe; Frechen; Germany). In addition, fluidized bed dryers can also be used.

表面後交聯可藉由加熱護套或吹入暖氣於混合器自身中來實行。同樣適合的為下游乾燥器(downstream dryer),例如箱形乾燥器、旋轉管式烘箱或可加熱螺桿。尤其有利於在流體化床乾燥器中實行混合及熱表面後交聯。The post-crosslinking of the surface can be performed by heating the jacket or blowing heating into the mixer itself. Also suitable are downstream dryers, such as box dryers, rotary tube ovens or heatable screws. It is especially beneficial for mixing and crosslinking after hot surface in a fluidized bed dryer.

較佳的反應溫度在100℃至250℃、較佳地110℃至220℃、更佳地120℃至210℃、最佳地130℃至200℃之範圍內。此溫度下之較佳停留時間較佳為至少10分鐘,更佳地至少20分鐘,最佳地至少30分鐘,且通常至多60分鐘。The preferred reaction temperature is in the range of 100°C to 250°C, preferably 110°C to 220°C, more preferably 120°C to 210°C, and most preferably 130°C to 200°C. The preferred residence time at this temperature is preferably at least 10 minutes, more preferably at least 20 minutes, most preferably at least 30 minutes, and usually at most 60 minutes.

隨後,可再次分類經表面後交聯之聚合物顆粒,其中將過小及/或過大的聚合物顆粒移除且再循環至方法中。Subsequently, the surface-post-crosslinked polymer particles can be sorted again, in which polymer particles that are too small and/or too large are removed and recycled to the process.

為進一步改良特性,可塗佈或再潤濕經表面後交聯之聚合物顆粒。To further improve the properties, the polymer particles that have been cross-linked after the surface can be coated or rewet.

再潤濕較佳地在30℃至80℃下,更佳地在35℃至70℃下,最佳地在40℃至60℃下執行。在過低溫度下,聚合物顆粒趨向於形成結塊,且在較高溫度下,水已經蒸發至可辨程度。用於再潤濕之水量較佳為1重量%至10重量%,更佳地2重量%至8重量%且最佳地3重量%至5重量%。再潤濕增大聚合物顆粒之機械穩定性且降低其靜態充電之傾向。在熱表面後交聯之後,再潤濕有利地於冷卻器中執行。The rewetting is preferably performed at 30°C to 80°C, more preferably 35°C to 70°C, and most preferably 40°C to 60°C. At too low temperatures, polymer particles tend to form agglomerates, and at higher temperatures, the water has evaporated to a discernible degree. The amount of water used for re-wetting is preferably 1% to 10% by weight, more preferably 2% to 8% by weight, and most preferably 3% to 5% by weight. Rewetting increases the mechanical stability of polymer particles and reduces their tendency to static charge. After the hot surface is post-crosslinked, rewetting is advantageously performed in the cooler.

用於改良自由膨脹速率及凝膠床滲透性(GBP)之適合塗料為例如無機惰性物質,諸如不溶於水的金屬鹽;有機聚合物;陽離子聚合物及二價或多價金屬陽離子。用於灰塵結合之適合塗料為例如多元醇。用於抵抗聚合物顆粒之非所需結塊傾向之適合塗料為例如煙霧狀二氧化矽,諸如Aerosil® 200;經沈澱矽石,諸如Sipernat® D17;及界面活性劑,諸如Span® 20。Suitable coatings for improving the free expansion rate and gel bed permeability (GBP) are, for example, inorganic inert substances such as water-insoluble metal salts; organic polymers; cationic polymers and divalent or multivalent metal cations. Suitable coatings for dust binding are, for example, polyols. Suitable coatings for resisting the undesired tendency of polymer particles to agglomerate are, for example, fumed silica, such as Aerosil® 200; precipitated silica, such as Sipernat® D17; and surfactants, such as Span® 20.

本發明進一步提供包含由本發明之方法製備之超吸收劑的衛生用品。The present invention further provides sanitary products containing the superabsorbent prepared by the method of the present invention.

方法: 下文中所描述及「WSP」所特指之標準測試方法描述於以下中:由Worldwide Strategic Partners EDANA (Herrmann-Debrouxlaan 46, 1160 Oudergem, Belgium, www.edana.org)及INDA (1100 Crescent Green, Suite 115, Cary, North Carolina 27518, 美國, www.inda.org)聯合公開之「Standard Test Methods for the Nonwovens Industry」, 2005版。此公開案可自EDANA及INDA二者獲得。method: The standard test methods described below and specified by "WSP" are described in the following: Worldwide Strategic Partners EDANA (Herrmann-Debrouxlaan 46, 1160 Oudergem, Belgium, www.edana.org) and INDA (1100 Crescent Green, Suite 115, Cary, North Carolina 27518, USA, www.inda.org) "Standard Test Methods for the Nonwovens Industry", 2005 edition published jointly. This public case is available from both EDANA and INDA.

除非另外陳述,否則量測應在23±2℃之環境溫度及50±10%之相對空氣濕度下進行。吸水性聚合物顆粒在量測之前經充分地混合。Unless otherwise stated, the measurement should be performed at an ambient temperature of 23±2°C and a relative humidity of 50±10%. The water-absorbing polymer particles are thoroughly mixed before the measurement.

離心保留容量 離心保留容量(CRC)藉由EDANA建議之測試方法第WSP 241.2 (05)號「離心後鹽水中之流體保留容量(Fluid Retention Capacity in Saline, After Centrifugation)」來測定。Centrifugal retention capacity The centrifugal retention capacity (CRC) is determined by the test method No. WSP 241.2 (05) recommended by EDANA "Fluid Retention Capacity in Saline (After Centrifugation)".

可萃取物 吸水性聚合物顆粒之可萃取物之含量藉由EDANA建議之測試方法第WSP 270.2 (05)號「可萃取(Extractable)」來測定。Extractables The extractable content of the water-absorbent polymer particles is determined by the test method No. WSP 270.2 (05) "Extractable" recommended by EDANA.

實例 實例1 藉由連續地混合去離子水、50重量%之氫氧化鈉溶液及丙烯酸,丙烯酸/丙烯酸鈉溶液經製備以使得中和度對應於71.3 mol%。單體溶液之固體含量為38.8重量%。Instance Example 1 By continuously mixing deionized water, 50% by weight sodium hydroxide solution, and acrylic acid, the acrylic acid/sodium acrylate solution was prepared so that the degree of neutralization corresponds to 71.3 mol%. The solid content of the monomer solution was 38.8% by weight.

所使用之聚烯系不飽和交聯劑為聚乙二醇-400二丙烯酸酯(二丙烯酸酯由具有400 g/mol之平均莫耳質量之聚乙二醇進行製備)。所使用之量為每t單體溶液2 kg交聯劑。The polyethylenically unsaturated crosslinking agent used is polyethylene glycol-400 diacrylate (diacrylate is prepared from polyethylene glycol with an average molar mass of 400 g/mol). The amount used is 2 kg of crosslinker per t monomer solution.

為引發自由基聚合,每t單體溶液使用1.03 kg之0.25重量%過氧化氫水溶液、3.10 kg之15重量%過二硫酸鈉水溶液及1.05 kg之1重量%抗壞血酸水溶液。To initiate free radical polymerization, 1.03 kg of 0.25% by weight aqueous hydrogen peroxide solution, 3.10 kg of 15% by weight sodium peroxodisulfate aqueous solution and 1.05 kg of 1% by weight ascorbic acid aqueous solution were used per t monomer solution.

單體溶液之輸送量為20 t/h。反應溶液具有23.5℃之饋入溫度。The throughput of the monomer solution is 20 t/h. The reaction solution has a feeding temperature of 23.5°C.

個別組分以以下量連續地定量至具有6.3 m³之容量的List Contikneter連續捏合機反應器(LIST AG,Arisdorf,Switzerland)中: 20 t/h          單體溶液 40 kg/h  聚乙二醇-400二丙烯酸酯 82.6 kg/h    過氧化氫溶液/過二硫酸鈉溶液 21 kg/h  抗壞血酸溶液The individual components are continuously quantified in the following quantities into the List Contikneter continuous kneader reactor (LIST AG, Arisdorf, Switzerland) with a capacity of 6.3 m³: 20 t/h monomer solution 40 kg/h Polyethylene glycol-400 diacrylate 82.6 kg/h hydrogen peroxide solution/sodium peroxodisulfate solution 21 kg/h ascorbic acid solution

在交聯劑之添加點與引發劑之添加位點之間,單體溶液用氮氣惰性化。Between the point of addition of the crosslinking agent and the point of addition of the initiator, the monomer solution is inertized with nitrogen.

在約50%之滯留時間之後,藉由研磨及篩分自製備方法獲得的細粒額外定量的添加(1000 kg/h)至反應器中。反應混合物於反應器中之停留時間為15分鐘。After a residence time of about 50%, the fine particles obtained from the preparation method by grinding and sieving are additionally quantitatively added (1000 kg/h) to the reactor. The residence time of the reaction mixture in the reactor is 15 minutes.

所獲得之水性聚合物凝膠藉助於振盪傳送帶施加於空氣循環帶式乾燥器之傳送帶。The obtained aqueous polymer gel is applied to the conveyor belt of the air circulating belt dryer by means of an oscillating conveyor belt.

空氣循環帶式乾燥器具有48 m之長度。空氣循環帶式乾燥器之傳送帶具有4.4 m之有效寬度。The air circulation belt dryer has a length of 48 m. The conveyor belt of the air circulation belt dryer has an effective width of 4.4 m.

振盪傳送帶具有5 m之長度。傳送帶具有0.8 m之寬度及0.5 m之有效寬度。水性聚合物凝膠於傳送帶上之靜止角為約15°。聚合物凝膠床於傳送帶上之橫截面為約0.04 m²。傳送帶之速度為0.5 m/s。The oscillating conveyor belt has a length of 5 m. The conveyor belt has a width of 0.8 m and an effective width of 0.5 m. The angle of repose of the aqueous polymer gel on the conveyor belt is about 15°. The cross section of the polymer gel bed on the conveyor belt is about 0.04 m². The speed of the conveyor belt is 0.5 m/s.

自一端位置行進,振盪傳送帶經由13°之第一樞轉角β1 加速至33°/s之角速度,經由20°之第二樞轉角β2 減速至17°/s之角速度且經由第三樞轉角β3 減速至另一端位置。總樞轉角為50°。雙程(自第一端位置至另一端位置且返回)持續約7 s。循環傳送帶具有聚四氟乙烯(PTFE)之表面。Moving from one end position, the oscillating conveyor is accelerated to an angular velocity of 33°/s through a first pivot angle β 1 of 13°, decelerated to an angular velocity of 17°/s through a second pivot angle β 2 of 20°, and passes through a third pivot angle β 3 decelerates to the other end position. The total pivot angle is 50°. The round trip (from the first end position to the other end position and back) lasts about 7 s. The endless conveyor belt has a surface of polytetrafluoroethylene (PTFE).

振盪傳送帶上之水性聚合物凝膠之溫度為90℃。The temperature of the aqueous polymer gel on the oscillating conveyor belt is 90°C.

用於傳送帶中之驅動滾筒及偏轉滾筒為棒狀滾筒。滾筒具有850 mm之總長度。滾筒之中間區域具有218.0 mm之直徑及426 mm之長度。朝向邊緣,滾筒之直徑減小7.4 mm達至210.4 mm。滾筒之直徑在滾筒之中部比滾筒之邊緣處大3.5%。角度α為約1°。棒狀滾筒具有15個棒(3),該等棒具有約20 mm之寬度、25 mm之高度及約10 nm之最小棒間距。孔口比率為22%。葉輪(2)各自具有六個具有40 mm之直徑的孔洞。The driving roller and deflection roller used in the conveyor belt are rod-shaped rollers. The roller has a total length of 850 mm. The middle area of the roller has a diameter of 218.0 mm and a length of 426 mm. Towards the edge, the diameter of the roller is reduced by 7.4 mm to 210.4 mm. The diameter of the drum is 3.5% larger in the middle of the drum than at the edge of the drum. The angle α is about 1°. The rod-shaped roller has 15 rods (3) with a width of about 20 mm, a height of 25 mm and a minimum rod spacing of about 10 nm. The orifice ratio is 22%. The impellers (2) each have six holes with a diameter of 40 mm.

循環傳送帶之壽命為約1.5年。The life of the circulating conveyor belt is about 1.5 years.

在空氣循環帶式乾燥器上,空氣/氣體混合圍繞水性聚合物凝膠連續地流動且使其乾燥。空氣循環帶式乾燥器中之滯留時間為37分鐘。On the air circulating belt dryer, the air/gas mixture flows continuously around the aqueous polymer gel and dries it. The residence time in the air circulating belt dryer is 37 minutes.

將經乾燥之聚合物凝膠研磨且篩分至150至850 µm之粒度級分。The dried polymer gel is ground and sieved to a particle size fraction of 150 to 850 µm.

所得吸水性聚合物顆粒具有34.9 g/g之離心保留容量(CRC)及8.5重量%之可萃取物含量。The obtained water-absorbing polymer particles have a centrifuge retention capacity (CRC) of 34.9 g/g and an extractable content of 8.5% by weight.

實例2 (比較實例) 程序如同實例1,不同之處在於使用具有218.0 mm之均一直徑之滾筒。滾筒之邊緣處之直徑同樣為218.0 mm。滾筒之直徑在滾筒之中部比滾筒之邊緣處大0.0%。角度α精確為0°。Example 2 (Comparative example) The procedure is the same as in Example 1, except that a roller with a uniform diameter of 218.0 mm is used. The diameter at the edge of the drum is also 218.0 mm. The diameter of the drum is 0.0% larger in the middle of the drum than at the edge of the drum. The angle α is exactly 0°.

循環傳送帶之壽命為約0.5年。The life of the circulating conveyor belt is about 0.5 years.

1:滾筒 2:葉輪 3:棒1: roller 2: impeller 3: great

圖1展示本發明之滾筒(1)之縱向截面。 圖2及3展示由葉輪(2)及棒(3)形成之棒狀滾筒。Figure 1 shows a longitudinal section of the drum (1) of the present invention. Figures 2 and 3 show the rod-shaped drum formed by the impeller (2) and the rod (3).

1:滾筒 1: roller

Claims (15)

一種藉由聚合包含以下之單體溶液或懸浮液來製備超吸收性顆粒之方法: a)     至少一種烯系不飽和單體,其攜帶酸基且至少經部分中和, b)     至少一種交聯劑及 c)     至少一種引發劑, 該方法包含對空氣循環帶式乾燥器中之所得水性聚合物凝膠進行乾燥、研磨、分類且視情況熱表面後交聯,其中該水性聚合物凝膠藉助於振盪傳送帶引入至該空氣循環帶式乾燥器中,該傳送帶在驅動滾筒及偏轉滾筒上運行,且該等滾筒中之至少一者之中部直徑比該滾筒之邊緣處大至少1%。A method for preparing superabsorbent particles by polymerizing a monomer solution or suspension containing the following: a) At least one ethylenically unsaturated monomer, which carries an acid group and is at least partially neutralized, b) At least one crosslinking agent and c) At least one initiator, The method includes drying, grinding, sorting and optionally heating the surface and crosslinking the obtained aqueous polymer gel in an air circulating belt dryer, wherein the aqueous polymer gel is introduced into the air circulating belt by means of an oscillating conveyor belt In a type dryer, the conveyor belt runs on a driving roller and a deflecting roller, and the diameter of at least one of the rollers is at least 1% larger than the edge of the roller. 如請求項1之方法,其中該驅動滾筒之中部直徑比該驅動滾筒之外邊緣處大至少1%。The method of claim 1, wherein the diameter of the middle portion of the driving drum is at least 1% larger than the outer edge of the driving drum. 如請求項1之方法,其中該驅動滾筒之中部及該偏轉滾筒之中部之直徑比該驅動滾筒及該偏轉滾筒之邊緣處大至少1%。The method of claim 1, wherein the diameter of the middle part of the driving roller and the middle part of the deflection roller is at least 1% larger than the edges of the driving roller and the deflection roller. 如請求項1至3中任一項之方法,其中該至少一個滾筒之中部直徑比該滾筒之邊緣處大3%至5%。The method according to any one of claims 1 to 3, wherein the middle diameter of the at least one roller is 3% to 5% larger than the edge of the roller. 如請求項1至3中任一項之方法,其中該至少一個滾筒之直徑在該滾筒之中間區域中為恆定的。The method of any one of claims 1 to 3, wherein the diameter of the at least one roller is constant in the middle region of the roller. 如請求項5之方法,其中該滾筒之中間區域佔該滾筒之總長度之40%至60%。Such as the method of claim 5, wherein the middle area of the roller accounts for 40% to 60% of the total length of the roller. 如請求項1至3中任一項之方法,其中該等滾筒具有150至300 mm之直徑。The method of any one of claims 1 to 3, wherein the rollers have a diameter of 150 to 300 mm. 如請求項1至3中任一項之方法,其中該等滾筒具有700至1000 mm之長度。The method of any one of claims 1 to 3, wherein the rollers have a length of 700 to 1000 mm. 如請求項1之方法,其中該兩個滾筒中之至少一者在運行表面中具有孔口且孔口比率為20%至50%。The method of claim 1, wherein at least one of the two rollers has an orifice in the running surface and the orifice ratio is 20% to 50%. 如請求項9之方法,其中該滾筒為由葉輪(2)及棒(3)組成之棒狀滾筒。Such as the method of claim 9, wherein the roller is a rod-shaped roller composed of an impeller (2) and a rod (3). 如請求項10之方法,其中該等棒(3)之間的最小距離為8至12 mm。Such as the method of claim 10, wherein the minimum distance between the rods (3) is 8 to 12 mm. 如請求項9至11中任一項之方法,其中該至少一個滾筒在端面中具有其他孔口。The method according to any one of claims 9 to 11, wherein the at least one roller has other apertures in the end surface. 如請求項12之方法,其中該至少一個滾筒為由葉輪(2)及棒(3)組成之棒狀滾筒且該端面中之其他孔口為該等葉輪(2)中之孔洞2。Such as the method of claim 12, wherein the at least one roller is a rod-shaped roller composed of an impeller (2) and a rod (3), and the other orifices in the end surface are the holes 2 in the impellers (2). 如請求項12之方法,其中該滾筒內存在之聚合物凝膠經吹出。The method of claim 12, wherein the polymer gel present in the drum is blown out. 一種衛生用品,其包含由如請求項1至14中任一項之方法製備之超吸收劑。A sanitary product comprising a superabsorbent prepared by the method according to any one of claims 1 to 14.
TW109102371A 2019-01-23 2020-01-22 Process for producing superabsorbent particles TW202035465A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP19153226.6 2019-01-23
EP19153226 2019-01-23

Publications (1)

Publication Number Publication Date
TW202035465A true TW202035465A (en) 2020-10-01

Family

ID=65275936

Family Applications (1)

Application Number Title Priority Date Filing Date
TW109102371A TW202035465A (en) 2019-01-23 2020-01-22 Process for producing superabsorbent particles

Country Status (2)

Country Link
TW (1) TW202035465A (en)
WO (1) WO2020151971A1 (en)

Family Cites Families (34)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6018690B2 (en) 1981-12-30 1985-05-11 住友精化株式会社 Method for improving water absorbency of water absorbent resin
JPS58180233A (en) 1982-04-19 1983-10-21 Nippon Shokubai Kagaku Kogyo Co Ltd Absorbing agent
US4734478A (en) 1984-07-02 1988-03-29 Nippon Shokubai Kagaku Kogyo Co., Ltd. Water absorbing agent
GB2208387B (en) 1987-07-28 1990-11-14 Dai Ichi Kogyo Seiyaku Co Ltd Process for continuously preparing acrylic polymer gel
WO1990015830A1 (en) 1989-06-12 1990-12-27 Weyerhaeuser Company Hydrocolloid polymer
CA2038779A1 (en) 1990-04-02 1991-10-03 Takumi Hatsuda Method for production of fluid stable aggregate
ES2097235T3 (en) 1991-09-03 1997-04-01 Hoechst Celanese Corp SUPER ABSORBENT POLYMER THAT HAS IMPROVED ABSORPTION PROPERTIES.
DE4138408A1 (en) 1991-11-22 1993-05-27 Cassella Ag HYDROPHILES, HIGHLY SOURCE HYDROGELS
JP3045422B2 (en) 1991-12-18 2000-05-29 株式会社日本触媒 Method for producing water absorbent resin
US5532323A (en) 1992-03-05 1996-07-02 Nippon Shokubai Co., Ltd. Method for production of absorbent resin
GB9208449D0 (en) 1992-04-16 1992-06-03 Dow Deutschland Inc Crosslinked hydrophilic resins and method of preparation
EP0632068B1 (en) 1993-06-18 1998-08-19 Nippon Shokubai Co., Ltd. Process for preparing absorbent resin
DE19646484C2 (en) 1995-11-21 2000-10-19 Stockhausen Chem Fab Gmbh Liquid absorbing polymers, processes for their production and their use
DE19543368C2 (en) 1995-11-21 1998-11-26 Stockhausen Chem Fab Gmbh Water-absorbing polymers with improved properties, processes for their production and their use
US6265488B1 (en) 1998-02-24 2001-07-24 Nippon Shokubai Co., Ltd. Production process for water-absorbing agent
TW460528B (en) 1998-04-28 2001-10-21 Nippon Catalytic Chem Ind Method for production of shaped hydrogel of absorbent resin
EP0989079A1 (en) * 1998-09-10 2000-03-29 Bernhard Beumer Maschinenfabrik KG Control system for the (straight) running of an elongate traction means, especially a transport belt
US6239230B1 (en) 1999-09-07 2001-05-29 Bask Aktiengesellschaft Surface-treated superabsorbent polymer particles
DE19955861A1 (en) 1999-11-20 2001-05-23 Basf Ag Continuous production of crosslinked gel polymer for use e.g. as an absorber involves polymerisation of monomers in a multi-screw machine with heat removal by evaporation of water and product take-off
US6979564B2 (en) 2000-10-20 2005-12-27 Millennium Pharmaceuticals, Inc. 80090, human fucosyltransferase nucleic acid molecules and uses thereof
DE20113181U1 (en) * 2001-08-08 2002-03-07 Beumer Maschf Gmbh & Co Kg Device for monitoring the (straight or skewed) run of the conveyor belt of a belt bucket elevator
DE10204938A1 (en) 2002-02-07 2003-08-21 Stockhausen Chem Fab Gmbh Process for post-crosslinking of a water absorbing polymer surface with a cyclic urea useful in foams, fibers, films, cables, especially sealing materials, liquid absorbing hygiene articles, packaging materials, and soil additives
DE10225943A1 (en) 2002-06-11 2004-01-08 Basf Ag Process for the preparation of esters of polyalcohols
ATE325150T1 (en) 2002-06-11 2006-06-15 Basf Ag (METH)ACRYL ESTER OF POLYALKOXYLATED GLYCERIN
RU2320677C2 (en) 2002-06-11 2008-03-27 Басф Акциенгезелльшафт Polyalkoxylated trimethylolpropane (meth)acrylic ester (variants) and its using for preparing polymers absorbing water-containing liquids
DE10331456A1 (en) 2003-07-10 2005-02-24 Basf Ag (Meth) acrylic esters of alkoxylated unsaturated polyol ethers and their preparation
DE10331450A1 (en) 2003-07-10 2005-01-27 Basf Ag (Meth) acrylic esters of monoalkoxylated polyols and their preparation
DE10355401A1 (en) 2003-11-25 2005-06-30 Basf Ag (Meth) acrylic esters of unsaturated amino alcohols and their preparation
WO2008087114A1 (en) 2007-01-16 2008-07-24 Basf Se Production of superabsorbent polymers
WO2010139680A2 (en) 2009-06-03 2010-12-09 Basf Se Method for producing water-absorbing polymer particles
DE102009036242B4 (en) * 2009-06-06 2011-11-10 Fred Bauersfeld Belt conveyors
JP5635685B2 (en) 2011-04-20 2014-12-03 株式会社日本触媒 Method and apparatus for producing polyacrylic acid (salt) water-absorbing resin
CN105980799B (en) * 2013-11-22 2019-09-03 巴斯夫欧洲公司 The method for preparing water-absorbing polymeric particles
JP2022502543A (en) * 2018-09-28 2022-01-11 ビーエーエスエフ ソシエタス・ヨーロピアBasf Se Method of manufacturing superabsorbent

Also Published As

Publication number Publication date
WO2020151971A1 (en) 2020-07-30

Similar Documents

Publication Publication Date Title
JP2016506981A (en) Method for producing water-absorbing polymer particles having high permeability of swollen gel bed, fast swelling speed and high centrifugal retention capacity
US8789774B2 (en) Method for producing water-absorbing polymer particles
US11325990B2 (en) Method for the production of superabsorbers
US8497337B2 (en) Process for producing water-absorbing polymer particles with improved color stability
TWI806887B (en) Classification process for superabsorbent polymer particles
US20160030979A1 (en) Process for classifying water-absorbing polymer beads
US20120308507A1 (en) Odor-Inhibiting Mixtures for Incontinence Articles
TW202035465A (en) Process for producing superabsorbent particles
JP6548723B2 (en) Water-absorbing polymer particles
TW202035464A (en) Process for producing superabsorbent particles
JP2019518116A (en) Method of manufacturing superabsorbent
TWI781194B (en) Process for producing superabsorbent polymer particles
JP6253575B2 (en) Method for producing water-absorbing polymer particles
US20220089789A1 (en) Method for producing superabsorbent particles
TW202035466A (en) Process for producing superabsorbent particles
US8653215B2 (en) Process for producing water-absorbing polymer particles
JP6250042B2 (en) Method for producing water-absorbing polymer particles in a polymerization reactor having at least two shafts rotating in parallel to the axis
CN112969529B (en) Method for producing superabsorbents
US11535719B2 (en) Method for the production of superabsorbers
US20240100506A1 (en) Process for producing superabsorbent particles
US20220185924A1 (en) Process for producing superabsorbent polymer particles
US20200392258A1 (en) Method for producing super absorber particles
KR20210036368A (en) Manufacturing method of super absorbent
JP2014515413A (en) Continuous production method of water-absorbing polymer particles