摘要:
The present invention provides a surface treatment method for a water-absorbing resin comprising three steps of: 1) a humidifying and mixing step for mixing a base polymer and a surface cross-linking agent solution to obtain a “humidified substance”; 2) a pretreatment step for raising temperature of said humidified substance to obtain a “pretreated substance”; and 3) a surface cross-linking reaction step for cross-linking said pretreated substance to obtain a surface cross-linked “water-absorbing resin”; wherein dew point in the pretreatment step of the above 2) is from 50° C. to 95° C., and temperature of said humidified substance is raised from temperature below the dew point up to a temperature of 10° C. higher than the dew point.
摘要:
An object of the present invention is to provide a water absorbent having excellent gel properties and showing excellent properties when used in a water-absorbing material of a sanitary/hygienic material such as paper diaper. Moreover, another object of the present invention is to provide a water absorbent which is safe and excellent in liquid permeability, and in which an amount of liquid permeability improver for improving the liquid permeability is reduced. The water absorbent is made from a water-absorbing resin prepared by a specific polymerization method and having a high degree of cross-linking, a high liquid holding property and a high gel strength (its swelling pressure of gel layer of is 35 kdyne/cm2 or more). This water absorbent is further processed to have a particular particle size distribution (95 wt % or more of its particles are less than 850ƒÊm but not less than 106ƒÊm, and logarithmic standard deviation (ƒĐƒÄ) is in a range of 0.25 to 0.45) and then surface cross-linked. After that, a liquid permeability improver is added therein.
摘要:
The present invention provides a method for producing a water absorbent resin particle, in high productivity, not only in a controlled manner of particle size but also enhancing fundamental property (absorption capacity or absorption capacity against pressure) of a water absorbent resin. A method for producing a water absorbent resin particle having the cross-linking polymerization step for an aqueous solution of an unsaturated monomer; the grain refining step for water-swellable, water-containing gel-like cross-linked polymer (a) obtained in the cross-linking polymerization step; the drying step for grain refined gel; and the crushing step for a dried substance, wherein, in the grain refining step for the water-swellable, water-containing gel-like cross-linked polymer (a), water-swellable, water-containing gel-like cross-linked polymer (b), having solid content or centrifuge retention capacity different from solid content or centrifuge retention capacity of the cross-linked polymer (a) by equal to or larger than 1%, is subjected to coexistence.
摘要:
The present invention relates to a method for continuous production of a water-absorbent resin by use of an continuous polymerization device having a charge part of a monomer aqueous solution; an endless belt on which the monomer and a hydropolymer formed are conveyed; and a discharge part of the hydropolymer, wherein the continuous polymerization device has side walls and a ceiling, and the space ratio in the device represented by the equation, “space ratio in the device=B/A”, is in the range of 1.2 to 20. In the equation, A is a maximum cross-sectional area (cm2) of the hydropolymer during the polymerization in the width direction of the endless belt, and B is a maximum cross-sectional area (cm2) of the space between the endless belt of the continuous polymerization device and the ceiling of the continuous polymerization device in the width direction of the endless belt.
摘要翻译:本发明涉及使用具有单体水溶液的电荷部分的连续聚合装置连续制造吸水性树脂的方法; 输送单体和形成的氢化聚合物的环状带; 和氢化聚合物的排出部分,其中连续聚合装置具有侧壁和天花板,并且由等式“器件中的空间比= B / A”表示的器件中的空间比在1.2 在该方程式中,A是在环形带的宽度方向上的聚合期间的氢化聚合物的最大横截面积(cm2),B是在环状带的宽度方向上的最大横截面积(cm2) 连续聚合装置的环形带和连续聚合装置的天花板在环形带的宽度方向上。
摘要:
The present invention provides: a production process for a particulate water-absorbent resin with high productivity, which production process is carried out in such a manner that the particulate water-absorbent resin will contain particles with particle diameters of 150 to 850 μm (but excluding 850 μm) in an amount of not smaller than 75 weight % of the particulate water-absorbent resin after the pulverization step or after the pulverization step and the drying step even if the adjustment of the particle diameters is not carried out by the sieving classification procedure; a novel particulate water-absorbent resin having high properties; and a sanitary material comprising this particulate water-absorbent resin. The production process for a particulate water-absorbent resin, according to the present invention, is carried out in such a manner that the particulate water-absorbent resin will contain particles with particle diameters of 150 to 850 μm (but excluding 850 μm) in an amount of not smaller than 75 weight % of the particulate water-absorbent resin after the pulverization step or after the pulverization step and the drying step; with the production process being characterized in that, in the pulverization step, a hydropolymer of a water-absorbent resin having a water content of 10 to 30 weight % is pulverized with a pulverizer.
摘要:
The present invention provides a production process by which a water-absorbent resin of excellent quality can be obtained at a low cost by reasonable steps in aqueous solution polymerization. The process for producing a water-absorbent resin comprises the step of polymerizing an aqueous solution of water-absorbent resin-forming monomers including acrylic acid and/or its sodium salt as major components, wherein: (1) the aqueous solution has a monomer component concentration of not less than 45 weight %; (2) the polymerization is carried out while water is evaporated so that the ratio (concentration ratio) between a solid component concentration in a hydropolymer as formed by the polymerization and a solid component concentration in the aqueous monomer solution will not be less than 1.10; and (3) the solid component concentration in the hydropolymer as formed by the polymerization is not more than 80 weight %.
摘要:
A thermal storage agent used, for example, for air-conditioning systems of buildings, exhibiting excellent thermal storage, thermal conduction and safety, and a manufacturing method thereof. The thermal storage agent contains particulate oil gel bodies prepared by letting an oil absorbent resin absorb, and thus swell with, a thermal storage oil-soluble substance, wherein the oily gel bodies have a unitary volume of not less than 0.01 cm.sup.3 and are in contact with one another. A manufacturing method in accordance with the present invention can produce the thermal storage agent by letting an oil absorbent resin that is prepared by suspension polymerization in a solution containing the oil-soluble substance absorb, and thus swell with, the oil-soluble substance.
摘要:
A process for preparing an absorbent resin includes the steps of: preparing a first crosslinking agent (A) including at least two polymerizable unsaturated bonds; preparing a second crosslinking agent (B) including at least two polymerizable unsaturated bonds and hydroxyl groups; preparing a crosslinking agent including (A) and (B) with a ratio of (A) to (B) ranging from 95/5 to 50/50; and polymerizing a hydrophilic unsaturated monomer having at least one carboxyl group using the crosslinking agent. The crosslinking agent includes a crosslinking agent which includes a main component at least 90 percent by weight, the main component being an ester having at least two polymerizable unsaturated bonds, wherein the ester is composed of a polyhydroxy alcohol (C) having not more than six carbon atoms and at least three hydroxy groups, and an unsaturated carboxylic acid (D); and a molecular weight ratio of the main component to a standard compound (E) is in the range of from 0.7/1 to less than 1.3/1, (E) being an ester composed of (C) that composes the main component, and (D) that composes the main component, in which all the hydroxy groups in (C) are ester-linked with (D).
摘要:
A method for the production of an acrylate by the neutralization reaction of acrylic acid and a basic substance, comprising sequentially (A) a step of supplying acrylic acid and said basic substance to water thereby subjecting them to a neutralization reaction while constantly retaining the neutralization ratio of acrylic acid within the neutralization reaction system in the range of 75 to 100 mol %, (B) a step of adjusting the neutralization ratio of acrylic acid within said neutralization reaction system in the range of 100.1 to 110 mol % by supplying said basic substance to said neutralization reaction system, (C) a step of retaining the neutralization ratio of acrylic acid within said neutralization reaction system in the range of 100.1 to 110 mol % for a period in the range of 1 to 120 minutes thereby allowing the neutralization reaction product to age, and (D) a step of adjusting the neutralization ratio of acrylic acid within said neutralization reaction system in the range of 20 to 100 mol % by supplying acrylic acid to said neutralization reaction system, and a method for the production of an acrylate-containing polymer using the acrylate.
摘要:
The invention provides biodegradable crosslinked polymers, which have a chelating effect and a dispersing effect to disperse an oily substance and an inorganic substance hardly soluble in water and are excellent in dispersion into water. The crosslinked polymers comprise; an ingredient of molecular weight 5,000 or less in 50% by weight, a bond having at least one of a group (II) represented by the chemical formula --CO--O-- and a group (III) represented by the chemical formula --CO--NH-- as a composition unit between main chains having a water-soluble oligomer structure having the functional group (I) represented by the general formula --COOM (here, M denotes anyone of a hydrogen atom, monovalent metal, divalent metal, trivalent metal, an ammonium group and organic amine group.), and showing a viscosity of 1,000 cP or less at 20.degree. C. by a 20% by weight aqueous solution of the crosslinked polymer.