TW384294B - Process for making flexible foams - Google Patents

Abstract

Process for preparing a flexible foam by reacting a prepolymer having an NCO value of 3-15% by weight, which is the reaction product obtained by reacting an excessive amount of a polyisocyanate with a polyether polyol or a mixture of such polyols, said polyol or mixture having an average nominal hydroxyl functionality of from 2 to 6, an average hydroxyl equivalent weight of from 500 to 5000 and an oxyethylene content of at least 50% by weight, with water, the amount of water being 15-500 parts by weight per 100 parts by weight of prepolymer, at the start of the reaction the temperature of the prepolymer being 10-50 DEG C and the temperature of the water being 10-50 DEG C higher than the temperature of the prepolymer and a process for preparing a flexible foam by reacting the above prepolymer with water in the presence of a super absorbent polymer.

Description

Printed by the Consumer Affairs Cooperative of the Central Bureau of the Ministry of Economic Affairs of the People's Republic of China. Using organic polyisocyanates (such as toluene diisocyanate (TDI) or diphenyl methane diisocyanate (MDI)) and polyether polyols, combined with The manufacturing of polyurethane flexible foams has been well established. The polydrums are generally polyoxypropylene polyols derived from propylene oxide, or poly (propylene oxide-ethylene oxide) polyols derived from a combination of propylene oxide and ethylene oxide. The attachment of ethylene oxide to the top end of a polyoxypropylene polyol is particularly important because it enhances the reactivity to isocyanates, with ethoxylated groups accounting for a small proportion of the total oxyolefin heterocycles. Polyols with a high ethylene oxide content (for example, 50% by weight or more) are usually used as a small amount of additives' to ensure that the foam has an open cell structure. It is not common to use polyethers at very high concentrations in combination with general isocyanates, as it has the effect of opening cells, which results in closed cell foams. It was found in the indefinite application of PCT / EP94 / 01659 that if essentially pure 4,4'-MDI or its derivative is used as a polyisocyanate, a high-concentration polyol with a high ethylene oxide content will be foamed with water. Under the formulation of the agent, flexible foams with compensating properties can be successfully produced. For the preparation of hydrophilic flexible foams, please refer to USP4137200 and USP4828542. Surprisingly, I have found that hydrophilic foams can be obtained using prepolymers (made from polyisocyanates and polyols with high ethylene oxide content) and water at different temperatures. Therefore, according to the present invention, a method for preparing a flexible foamed crossbond by using a reaction of a prepolymer and water is provided; the prepolymer contains 3 to 5 weight percent of NCO 値, which utilizes excess polyisocyanate and polyether polyol The paper size of the paper or its mixed table applies the Chinese National Standard (CNS) M specification (2 丨 0 × 297 mm. Q1Tοι (please read the note f on the back before filling out this page). Packing A7 B7 V. Description of the invention (2) The reaction product obtained by the reaction of the product (the polyol or mixture contains an average of 2 to 6 units of several functional groups) is preferably 2 to 4, and the average equivalent is 5. 0 to 5000, preferably 1000 to 5000, and an ethylene oxide content of at least 50% by weight; the amount of water used per 100 parts of prepolymer weight, 15 to 500 parts by weight of water; characterized by the start of the reaction, The prepolymer depletion temperature is 10 to 50, preferably 15 to 30 ° C, and more preferably room temperature. The water temperature is 10 to 50 * C higher than the prepolymer temperature, and 20 to 45 °. C is preferred. The temperature of water is 25 to 90T, preferably 40 to 70 ° C, and 55 to 65. (: best. A preferred embodiment of the invention is a method for preparing a flexible polyurethane foam by using a reaction of a prepolymer with water; the prepolymer contains 3 to 10 weight percent of NCO 値, which is based on utilizing excess polyisocyanate (containing at least 65% by weight, preferably at least 90, and more preferably at least 95, 4,4, -diphenylmethylene diisocyanate, or a variant thereof) and a reaction product obtained by the reaction of a polyether polyol or a mixture thereof, the Polyols or mixtures have an average rated hydroxyl functionality of 2.5 to 3.5, an average hydrocarbyl equivalent of 1,000 to 3,000, and an ethylene oxide content of 50 to 85 weight percent; the amount of water used is 100 parts per 100 parts Pre-polymerized weight, 30 to 300 parts by weight of water; characterized in that at the beginning of the reaction, the temperature of the prepolymer is 10 to 5 (TC, 15 to 3 (TC is preferred, and room temperature is the best) 25 to 9 (TC, preferably 40 to 70 ° C, and most preferably 55 to 65 ° C ', and the water temperature is 10 to 5 (^ (:, to 20 to 45 °) higher than the prepolymer temperature C is better. Surprisingly, I have found that a hydrophilic flexible foam having good quality with low density and hardness can be obtained , Where the density and hardness of the foam are compared with the reaction of prepolymers and water with the same or similar reaction initiation temperature, compared with ____ -5- This paper size is applicable to the Chinese National Standard (CNS) grid (210 > < 297 mm) (Please read the notes on the back before filling out this page) • ο.-Ordered by the Central Government Bureau of the Ministry of Economic Affairs, Printed by the Bayer Consumer Cooperative ¾ A7 ______B7________ 5. Description of the invention (3) Not accepted, or even completely It is not affected by the amount of water used. For the sake of convenience, the term average in this application is not specifically defined except it is explicitly expressed as an average number elsewhere. The polyisocyanate used to prepare the prepolymer is selected from the group consisting of aliphatic, cycloaliphatic fats and aromatic polyisocyanates, especially diisocyanates such as hexane diisocyanate, isophorone diisocyanate, cyclohexane-1,4- Diisocyanates, 4,4'-dicyclohexylmethane diisocyanates, and. And p-tetramethylxylene diisocyanates, and especially aromatic polyisocyanates such as toluene diisocyanate (TDI), benzene diisocyanates and more preferably Diphenylmethane diisocyanate (MDI) and its analogs with two or more isocyanate functionalities, such as crude MDI and polymerizable MDI. The preferred polyisocyanate is diphenylmethane diisocyanate, which is selected from the group consisting of pure 4,4'-MDI, 4,4'-MDI and 2,4-MDI and less than 10 weight percent of 2,2'-MDI. Structural mixtures, and modified variants thereof, including carbodiazidamine, ureidoimine, rauric acid, urethane, urethane, urea or biuret family, etc., like ureidoline Amine and / or carbodiamidate-modified MDI has an NCO content of at least 25% by weight, and aminodiacetate-modified MDI obtained by the reaction of excess MDI and a low molecular weight polyol (molecular weight to 1000) has at least 25 NCO content by weight. If desired, mixtures of the isocyanates described above can be used. Polyisocyanate may contain dispersed urea particles and / or urethane particles prepared by conventional methods, such as adding a small amount of isophorone diamine to the polyisocyanate. • The best polyisocyanate used to prepare the prepolymer is at least 65% by weight, preferably at least 90, and more preferably at least 95, 44 diphenylmethyl ----_- 6- This paper Ruler applicable to China National Bare Standard (CNS) (21Gxi7 public envy) -----. QII (Please read the precautions on the back before filling this page)

.II Printed by the Consumers' Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs A7 B7 __ 5. Description of the invention (4) Polyisocyanate of alkane diisocyanate or its variant. It may consist essentially of pure 4,4 ′ · diphenylmethane diisocyanate, or its isomers with one or more other organic polyisocyanates (especially other diphenylmethane diisocyanates, such as 2,4 ′ · Isomers, consisting of a mixture of 2,2 · -isomers, if necessary. The best polyisocyanate may also be a variant of MDI, derived from a polyisocyanate composition containing at least 65% by weight of 4,4 · -diphenylmethane diisocyanate. MDI variants are well known in the art and are used in the present invention, especially containing liquid products obtained by the introduction of ureidomethylamine and / or carbodiamido groups to the polyisocyanate, which are carbodiamine and / or Pulsed imine-modified polyisocyanate contains at least 25% by weight of NCO 値, and / or the polyisocyanate is reacted with one or more polyols having a functionality of 2 to 6 hydroxyl groups and a molecular weight of 62 to 1000 to obtain a modified Polyisocyanate containing at least 25% by weight of NCO 値. The polyether polyols or polyether polyol mixtures used to prepare the prepolymers preferably have an average hydroxy functionality of 2 to 4 on average, most preferably 25 to 35 'and an average hydroxyl equivalent of 1,000 to 3000, and acetic oxide content is 50 to 85 weight percent. Polyether polyols include products obtained by the polymerization of ethylene oxide, optionally polymerization and other cyclic oxides, such as tetrahydrofuran and preferably propidium oxide, and if needed, a multifunctional starter Together. Suitable starter compounds contain most active hydrogen atoms, and include water, succinate, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, ethanolamine, diethanolamine, triethanolamine, and toluenediamine. Amine, diethylpyrene-phenylenediamine 'diphenylmethanediamine' ethylenediamine, cyclohexanediamine, This paper is applicable to China National Standards (CNS) Congwei (21Gx297) ----- ο ------ ΐτ ------ ΟΊ (Please read the notes on the back before filling this page) A7 B7 V. Description of the invention (5) Cyclohexanedimethanol, m-benzene Diphenol, 2,2-di-p-phenol methane, glycerol, trimethylolpropane, 1,2,6-hexanetriol, pentaerythritol, and hexahexanol. Mixtures of initiators can be used. If other cyclic oxidations are used Polyols can be obtained by the simultaneous or continuous addition of acetic oxide and other cyclic oxides (such as those fully described in the prior art). Polyols are preferred to obtain an average rated hydroxyl functionality of 2.5 to 3.5. "Polyols" can be used for appliances with a rated cigarette functional group of 3, or an average rated number of functional groups of 2 to 6 Alcohol mixtures, so that the mixture falls within the functional range of 2.5 to 3.5 above—Polyol mixtures that are generally usable are pre-titled, which have the functionalities, equivalents and ethylene oxide content required above The term "average rated hydroxyl functionality" as used herein refers to the average functionality of the polyol composition (the number of hydroxyl groups per molecule), which is assumed to be the average functionality of the polyoxyolefin polyol. It is equal to the average functional group (the number of active hydrogen atoms per molecule) in the initiator used in its preparation, although the former is slightly lower than the latter due to the fact that some terminals are not saturated. Alcohols or mixtures of polyols may contain polymer particles. The polymer-modified polyols have been fully described in prior art, and are included in polyoxyolefin polyols, with one or more vinyl monomers such as acrylonitrile And styrene) in situ polymerization, or in situ reaction of polyisocyanate and amine or hydroxy-functional compounds (such as triethanolamine) in polyoxyolefin polyol The prepolymer is made of polyisocyanate at a preferred temperature of 40 to 90 ° C (please read the note on the back before filling this page) ^ β Printed by the Central Laboratories of the Ministry of Economic Affairs -8 -

Printed by A7 ______B7____, Shellfish Consumer Cooperatives, Central Bureau of Standards, Ministry of Economic Affairs. 5. The description of invention (6) and the traditional method of reaction of polyhydric alcohols. The relative amount of the two is 3 to 15% by weight of NCO 値. It is preferably 10% by weight. The prepared prepolymer is liquid under ambient conditions. If necessary, a small amount (up to 30% by weight) of additional polyisocyanate, especially MDI, can be added to the prepared prepolymer. To improve the stability of the prepolymer, organic acids or Lewis acids can be added. The viscosity of prepolymerization is 25. (: Hour, preferably at most 10,000 milliPascals. Second. In preparing the prepolymer, the isocyanate functionality of the polyisocyanate and the average rated hydrocarbyl functionality of the polyol or polyol mixture should be avoided. Both are 20. If the functional degree of one is 2.0, the functional degree of the other is preferably at least 2.2. The prepolymer reacts with water, and the amount of water used is 100 parts by weight of the prepolymer, 15 To 500 parts by weight of water, preferably from 30 to 300, and most preferably from 40 to 25. The reaction mixture forming the foaming heterogeneous mixture may contain one or more additives for preparing a flexible foam. Additives include catalysts (such as tertiary amines and tin compounds), surfactants and foam stabilizers (such as silicone-oxyalkylene copolymers, and polyethylene oxide / polypropylene oxide copolymers, and polyethylene oxide Polymers), chain extenders (such as low-molecular-weight diols or diamines), cross-linking agents (such as triethanolamine, glycerol, and trimethylolpropane, fire retardants, organic or "', organic fillers, pigments, so-called stagnation Inhibitor of foaming effect Oxane), internal stress release agents, antibacterial agents, bactericides, and medicaments. However, useful flexible foams can also be obtained without any of these additives. In addition to the weight per 100 parts of prepolymer, add to 10 or even 5 copies of the above-mentioned paper from 14 Chinese S Postal Secretary (CNS) A4 ^ (21 () x29 »^ y (please read the precautions on the back before filling out this page) d. Order the Central Ministry of Economic Affairs 搮Printed by the Zhuhai Bureau Shellfish Consumer Cooperative A7 £ 7_ 5. Description of the Invention (7) Polyethylene oxide / polypropylene oxide copolymers and polyethylene oxide polymers are not important except for any additives. If used, the additives Additives are best mixed with water in advance. When using these (co) polymers, I was surprised to find that the foam has very good wetting properties and can absorb and retain water and / or several times the weight of the foam It has a network of cells. The network of cells is produced in the presence of 0.01 to 10 parts by weight (per 100 parts of prepolymer weight) of a polyol by reacting prepolymers with water. With an average molecular weight of 500 to 10,000, and a rated hydroxyl functionality of 2 to 6, on average, The polyol is a block copolymer of a polyethylene oxide polymer or a polyethylene oxide polypropylene oxide, and contains at least 30% by weight of ethylene oxide. The polyol is used in an amount of 0.05 to 3 parts by weight per 100 parts of the prepolymer. These polyols are known in the art and are commercially available. For example, Synpwonic ™ PE L44, L64, F68, P75, P84, P85, and F87 are available from Imperial Chemical Industries PLC (Imperial Chemical Industries PLC) PLC) 0 When the polyol used contains 35 to 70 weight percent ethylene oxide content, preferably 40 to 70; and when the average rated hydroxyl functionality of the polyol is preferably 2, when using these polyols, Wetting properties are particularly obtained. When the polyol used contains 70 to 100% by weight of ethylene oxide (100 is the most suitable), the use of these polyols can particularly obtain the reticulate properties; when preparing these reticulated foams, it is preferred to use At least 40 parts water per 100 parts prepolymer. The water and the polyol are preferably pre-mixed before the prepolymer and water are reacted in the presence of the polyol. _-10-_ This paper size applies to China National Standard (CNS) A4 (210X297 mm) ----------- Q ------------ (please first Read the notes on the reverse side and fill in this page) Printed by the Central Government Bureau of the Ministry of Economic Affairs of the Shellfish Consumer Cooperative «. A7 ____B7 V. Description of the invention (8) A further method according to the present invention can be implemented in the presence of a superabsorbent polymer The use of water above the prepolymerization temperature will be discussed in more detail later. The type and amount of the superabsorbent polymer and how to use it will be described later. · The reaction system for making hydrophilic flexible foams (with ‘good properties’) is a very simple method. The preferred prepolymer has a low viscosity, which improves the ease of handling and processing when manufacturing flexible foams. The foam has a desired color (white), has open cells or is easily extruded, and Has an extrusion setting of less than 20 percent (ASTMD 3574-77, Test D, 50 percent dryness), especially when no surfactant is used. The purity and simplicity of the chemicals used in the manufacture of prepolymers ensure that they have the lowest extractables in the manufacture of flexible foams, which makes these foams in areas that need to be in contact with the human body Particularly useful, such as medical and health applications. Foams can be made in the shape of flat plates and molded products, and can be used to reduce vibration, diapers, sponges, wound bandages, stoppers, cosmetic pads, drug release products, plant growth media, and food plate absorbents. The present invention further relates to a method for preparing a hydrophilic flexible foam in the presence of a superabsorbent polymer by reacting a previously defined prepolymer with 15 to 500 parts by weight of water per 100 parts of prepolymer weight. . The well-known superabsorbent polymer (SAP) is as follows. SAP or water-absorbing polymers or hydrogels are water-insoluble hydrophilic polymers that can swell and absorb 10 to 100 times their own weight of water, eyelid, physiological or body fluids. It consists of polymer electrolyte or other highly hydrophilic polymer matrix, usually along ___- 11 -_ This paper size applies to China National Standard (CNS) A4 specification (210X297 mm) -------- -ο ------ ίτ ------ Cr (please read the note on the back before filling in this page) A7 B7__ 5. Description of the invention (9) The macromolecular chain contains a cross-linking group to Avoid dissolution. It may be natural SAPs, such as guar gum, other natural gums and starches, and preferably synthetic SAPs, including acrylic or methacrylic acid, or its esters, nitriles, amines, or Class-based polymers, polysaccharides, maleic anhydride polymers, polyvinyl alcohol, poly (N-2 alkenyl-i this ketone), and dipropenyl dialkyl quaternary ammonium salts. We refer to a retrospective article to survey SAP: "Water_Absorbent Polymers: A Patent Survey", Riccardo PO in JMS-Rev. Macromol. Chem. Phys ·, C34 (4), 607-602 (1994). The superabsorbent polymers disclosed in this article can be used in the present invention. Printed by the Central Bureau of Quasi-Ministry of Economic Affairs, Shellfish Consumer Cooperative (please read the notes on the back before filling in this card) SAPs based on acrylic or methacrylic monomers are acrylic or methacrylic acid, esters, nitriles Polymers made from amines or their salts by free radical polymerization, if necessary, reacted with other unsaturated monofluorenes, such as maleic acid, fumaric acid, or derivatives that decompose aconitic acid, Vinyl-substituted continuous acid or ammonium salts, olefinic and styrenic monomers, smoke-based or ammonium-based acrylic and methacrylic acid salts, unsaturated continuous acid salts, propidinolide alkyl sulfonates , Vinyl sulfonate, styrene sulfonate, vinyl benzyl sulfonate, N, N'-methenylbispropenamide, di (alkylaminoalkyl) acrylic acid and methacrylate , Carbonyl-containing heterocyclic N-vinyl monomers, such as N-ethenyl-2-u this Lomin 'N-vinyl-2 caprolactam and N-acetamidin-2-morpholinone . Such polymers can be prepared by methods known in the art, and if necessary, starters, crosslinking agents and surfactants known in the art are used, for example, see General, pages 610 to 632. Can use a small amount of polyethylene co-monomer free radical copolymerization reaction, or polymers with carboxylates or carboxylic acid pendant groups ___- 12 -__ This paper size uses the Chinese national half (CNS > Λ4 Specifications (210X297 mm) ~ Printed A7 of Shellfish Consumer Cooperative, Central Bureau of the Ministry of Economic Affairs _ _B7_ _ V. Description of the invention (10) Reaction with polyethylene oxide, South-based ethylene oxide and / or polyol Cross-linking reaction is performed. Superabsorbent polymers based on polysaccharides can be selected from, for example, starch-grafted copolymers and modified cellulose polymers. These SAPs are derived from unsaturated monomers such as propylene Nitrile, acrylic acid or acrylamide) is grafted onto polysaccharides (such as starch or cellulose), and then made by saponification if necessary. Such polyabsorbent-based superabsorbent polymers are well known in the art, It can be prepared by methods known in the art; see General, pages 63 2 to 638. SAPs based on maleic anhydride polymers use maleic anhydride and hydrophobic comonomers (such as olefins or vinyl ethers). ) Manufactured by methods known in the art; see General 638 to 642. Further, SAPs that may be used are polymers prepared by polymerization, such as dipropenyl dialkyl quaternary ammonium salts in polyfunctional diethylene compounds and / or crosslinkers (such as gas In the presence of tripropenylmethylammonium); polyoxylean (such as polygasified ethylene) which is crosslinked by, for example, hydrazone and glutaric acid in the presence of sulfuric acid; using, for example, diethylbenzene Poly (N-ethenyl) and poly (N-methyl, N-vinylacetamide) crosslinked by dipropionate or diethylene glycol-ethylenic acid. This class SAPs and methods of making them are known in the art; see general, pages 642 to 647. Preferred SAPs are selected from acrylic or methacrylic acid, vinegar, riding, amines and / or their salts. Based on superabsorbent polymers; superabsorbent polymers based on polyacetate and superabsorbent polymers based on maleic acid gp. SAP can be used in polyurethane foam. There are three The method can be used to gather together __ -13- This paper size is applicable to China National Standard (CNS) A4 size (210X297 mm) ----- II- ------. ο ------ ΐτ ------ Cr (Please read the notes on the back before filling in this page) The Central Government Bureau of the Ministry of Economic Affairs, Shellfish Consumer Cooperative, India A7 _B7_ 5 Explanation of the invention (n) $ Urethane foam: 1. Combining the ingredients for manufacturing SAP and the polyurethane foam, so that SAP and polyurethane foam are formed at the same time; see for example US4731391 and EP-163150. This knot It is an infiltration-type network structure. The disadvantage of this method is that due to the existence of a relatively large number of reactive compounds, this method is inconvenient and difficult to control, and the monomers used to prepare SAP are often dangerous and Toxic substances; this requires manufacturers of flexible foams to use additional measuring equipment to protect the safety and health of employees and the environment. 2. Liquid is used as the carrier of SAP, and SAP is incorporated into the polyester foam by impregnation method; see EP-41934. The disadvantage of this method is that the preparation of SAP-containing foam requires several additional method steps, making this method less economically attractive. In addition, the flexible cell must have a larger cell size than the expanded SAP particles. This means a stricter limit on the SAP particle size. 3. SAP granules are mixed with ingredients used to make flexible foam. EP-453286 discloses a superabsorbent foam material based on polyurethane foam and containing superabsorbent material. This superabsorbent material may be selected from known ones and mixed with a conventional polyurethane composition, which is then used in the manufacture of polyurethane foams. The composition contains a polyol, a catalyst, a polyisocyanate, and a small amount of water. US5336695 describes a polyurethane foam-based hydrophilic foam, which is easily obtained from polyols, diisocyanates, superabsorbents, catalysts, and small amounts of water. -»_; ___- 14- _ this paper" tss home materials (CNS > (210X297 Male I) '' ---------- ό! ----- IIT ------ Cr (Please read the notes on the back before filling this page) A7 B7 V. Description of the invention (12) US4201846 reveals the use of a fiber made of polyvinyl alcohol polymer in a hydrophilic foam to reduce the expansion of the foam Polyurethane is manufactured by the reaction of prepolymer and water in the presence of fibers and shows improved tension and tear properties, as well as reducing the increase in volume caused by absorption of water. US3900030 discloses that the content of The hydrophilic foam of the expanded polymer is used in hemostatic cotton. The amount of polymer used is important to avoid leakage. The foaming system is a mixture of polymer and polyol and diisocyanate in the presence of a catalyst and a small amount of water Reaction manufacturing. US4603076 discloses that in the presence of a hydrophilic compound and a catalyst, an MDI-based prepolymer is foamed with a non-aqueous blowing agent and a polyethylene oxide polyol to prepare a hydrophilic foam. The prepolymer Based on a mixture of MDI and polymerizable MDI US4985467 discloses the preparation of hydrophilic foams by the reaction of polyisocyanate, polyol and water, and the subsequent heat reticulation in the presence of superabsorbent materials. (Please read the notes on the back before filling this page) EP-547765 and W094 / 29361 disclose the use of a prepolymer made of 4,4'-MPI and having a weight of 50 to 85 Polyether polyols with a percentage of ethylene oxide content, and water. Surprisingly, I have found that hydrophilic flexible foams can be used in the presence of the superabsorbent polymer (SAP), using the superabsorbency described above The polymer is prepared by the reaction of the above-mentioned prepolymer and a large amount of water. The foamed crossbones can be manufactured without heat netting. SAP can be premixed with the prepolymer. For foam manufacturers, __- 15-_ This paper size is applicable to the Chinese National Standard (CNS) A4 (210X297 mm). The Central Government Bureau of the Ministry of Economic Affairs, Shellfish Consumer Cooperative Co., Ltd. printed A7 _ B7 V. Description of the invention (13) This makes the method become Very simple Only water needs to be added. From the environmental point of view, the foaming ceremony is also very attractive. In addition to prepolymer, SAP and water, no additives are needed, especially no catalyst. The foaming Zhao has very Desirable properties: 'It shows limited shrinkage, has open cells, is stable, does not resemble coking, and has very good water absorption and retention characteristics, very good wetting and mechanical properties' such as Tear strength (dry and wet) and elongation. In addition, the foam has a soft feel. The previous title was to make a reticulated foam without using the above polymers and copolymers. Therefore, the present invention further relates to a method for preparing a flexible foam by using a reaction of a prepolymer and water, characterized in that the reaction of the prepolymer and water is performed in the presence of a superabsorbent polymer. The prepolymer has 3 to 15 weight percent of NCO 値, which is a reaction product obtained by reacting an excess of polyisocyanate and a polyether polyol or a mixture of polyols, and the polyol or mixture has an average rated hydroxyl functional group of 2 to 6 Degrees, preferably from 2 to 4, average hydroxyl equivalents from 500 to 5000, preferably from 1,000 to 5000, and at least 50 weight percent ethylene oxide content; the amount of water used is per 100 parts by weight of prepolymer , 15 to 500 parts by weight of water. The invention still further relates to a composition comprising a prepolymer and a superabsorbent polymer having 3 to 15% by weight of NCO (R). The prepolymer is reacted using a mixture of excess polyisocyanate and polyether polyol or polyol The resulting reaction product, the polyol or mixture has an average warp functionality of 2 to 6 on average, and has an average equivalent weight of 1000 to 5000, and an ethylene oxide content of at least 50% by weight — -16 _ this paper size Chinese National Standard (CNS) A4 threat (210X297 male dust) ----------- C— (Please read the note on the back before filling this page)

tT A7 B7 V. Description of the invention (14) Generally, the amount of superabsorbent polymer used is 100 parts by weight of prepolymer, 1 to 100 parts by weight of superabsorbent polymer (pbw), preferably 5 to 80 pbw, 10 to 70 pbw is the best. The prepolymers used in the method according to the present invention, and the manner in which they are used to produce foams, are the same as the foregoing. The preferred water usage is as described above. In particular, it is preferable that the foam is produced without the presence of additives (especially a catalyst), as described above, with the exceptions of the above-mentioned polyethylene oxide polymers and polyethylene / polypropylene oxide copolymers. The same measurement can be performed when the foam has particularly good wetting properties, or when the foam exhibits reticulation as desired. Printed by the Central Standards Bureau of the Ministry of Economic Affairs, Shellfish Consumer Cooperatives (Please read the notes on the back before filling out this page) SAPs can be selected from those described in the general article as described above. In particular, it can be self-crosslinked polyacrylic acid salt and polyacrylamide and its salts. Such SAPs are commercially available, such as SANWET ™ IM 3900G, IM 3746/1 and E 394-95 from Hoechst / Cassella. In addition, the SAPs may be selected from SAPs grafted with starch or cellulose, using, for example, acrylonitrile, acrylic acid, or acrylamide as the unsaturated monomer. These SAPs are also commercially available, such as SANWET IM 7000 ° from Hearst, Kessler, and different SAPs can be used in combination. SAPs can be mixed with prepolymer and water while prepolymer and water are mixed, or SAPs and prepolymer can be premixed. SAPs are better not pre-mixed with water. Mixing can be done manually, mechanically, or under high shear mixing conditions. In addition, the present invention relates to absorbent articles (such as diapers, sponges, wounds --- _; _-17 -__ This paper has been re-used in China National Standard (CNS) A4 (210X297 mm) Β _ V. Description of the invention (15) Bandage and hemostatic cotton), including a catalyst-free superabsorbent polymer containing a hydrophilic polyurethane flexible foam. The preferred foam is diphenylmethane diisocyanate. The invention is further illustrated by the following examples. Example 1 Polyol 1 is a polyether (starting with a triol), has a messy ethylene oxide and propylene oxide body, contains 77% ethylene oxide content, and has a molecular weight of about 4,000. A polymer was prepared by reacting 70 parts by weight of a polyol and 30 parts by weight of 4,4'-MDI. From this prepolymer, a flexible foam was prepared by reacting it with different amounts of Pluronic PE 6200 (an EO / PO surfactant from BASF-Pluronic as a trademark) containing 0.4% by weight. This prepolymer had 7.85 weight percent NC0 値 and a viscosity at 25 ° C of 6000 milliPascal seconds. Before the reaction, the temperature of the prepolymer was room temperature (22 ° C). Before the reaction, the amount and temperature of water, and the density and hardness of the obtained foam are shown in Table 1 described later. Density and hardness measurements were carried out in an oven at 60 ° C until no further weight loss occurred. (Please read the notes on the back before filling in this page) Printed by the Central Government Bureau of the Ministry of Economic Affairs, Shellfish Consumer Cooperatives-18-This paper is applicable to China National Standard (CNS) A4% grid (210X297 mm) B7 V. Invention Explanation (16) Table 1 Experiment 1 * 2 * 3 * 4 * 5 6 7 8 Weight per 100 parts of prepolymer heavy water 30 110 30 110 30 110 30 110 Water temperature (C) 10 10 25 25 45 45 65 65 Core Density (kg / m3) 75 170 72 144 68 91 64 74 Hardness, CLD, 40% (仟 Pascal) [SO 3386 9.1 17.1 7 14.5 5 6.4 3.6 4.3 (Please read the precautions on the back before filling this page) Printed by the Central Bureau of quasi-Ministry of Economic Affairs, Shellfish Consumer Cooperatives * Comparative Example Example 2 The following example uses Synperonic surfactant. Table 2 EO content, weight percent molecular weight Synperonic PE L 43 30 1900 L 44 40 2200 L 64 40 2900 P 84 40 4200 P 85 50 4650 F 87 70 7700 F 38 80 4800 Polymer weight, use it and 70 parts -19-This paper size uses China National Standard (CNS) A4 specification (210X297 mm) A7 ___B7_______ V. Description of the invention (17) 0.56 parts by weight Synperonic polyol Reaction of water to prepare a scorch foam. The pre-polymer had a temperature of 22X before the reaction. The temperature of the water before the reaction, the type of Synperonic used, and the results of the wetting test are shown in Table 3. Table 3 _ _ Experimental Synperonic PE Wetting Test Water Temperature Type (sec) (° C) 1 L 43 53 45 2 L44 11 45 — 3 L64 8 45 4 P84 2 .45 5 P 85 1 45 6 F 87 5 45 7 F 38 130 45 8 * L 64 238 20 9 «P 84 254 20 10 * P 85 267 20 --------- ό ------ IT ------ 9 (Please listen first (Please read the notes on the reverse side and fill in this page again.) The comparative example printed by the Shell Bureau Consumer Cooperative of the Central Board of Governors of the Ministry of Economic Affairs. The foams obtained from experiments 8 to 10 are mainly closed cells. Wetting test: A piece of dried foam sample with a size of 9 X 9 X 1 cm is placed on the water surface (one of the two larger sides of the sample is placed on the water surface), and the upper surface of the sample is visually required to be completely wet Time. Based on the above prepolymer (100 pbw, 221), water and surfactant (in the _____- 20 -___) This paper ruler is from China National Standard (CNS) from Waki (2ωχ297 public princes) '' Central Ministry of Economic Affairs Rubbing of the staff of the Prospective Bureau Consumer Co-operative Association A7 ΒΊ_ 5. Description of the invention (18) 0.8% by weight in water) to produce foam. Table 4 shows the amount of water used (per 100 pbw of prepolymer, pbw of water), temperature, and type of surfactant, along with an indication of whether the resulting foam is a reticulated foam. Table 4 Experimental surfactant water volume Water temperature, (° C) Reticulated foam 11 * G 26 70 25 Non 12 G 26 70 60 Yes, completely 13 F 68 70 80 Yes, completely 14 * F 87 110 25 Non 15 F 87 110 45 Yes, most of the cells 16 * P 75 110 25 Non 17 P 75 110 45 Yes, a few of cells * Comparative Example G26 is a polyethylene oxide triol with a molecular weight of 1200. F68 is PEF68: EO content 80% by weight, molecular weight 8350. P75 is Synperonic PE P75: 50 weight percent EO content, molecular weight 4150. Example 3 The 100 pbw prepolymer from Example 1 was reacted with 70 pbw of 0.8 weight percent Synperonic L64 water. Before the reaction, the temperature of the prepolymer and water -21-This paper size is applicable to the Chinese National Kneading Car (CNS) A4 specification (210X297 mm) ----------- C! (Please read the Note for refilling this page),-= * Printed A7 B7, Shellfish Consumer Cooperatives, Central Bureau of Standards, Ministry of Economic Affairs 5. Description of the invention (19) Degrees are room temperature (22 ° C) and 45 ° C, respectively. Before combining and mixing water and pre-polymer, add SAP to the pre-polymer and mix the "type and amount of SAP used (pbw per 100 pbw pre-polymer) see Table 5, Experiments 1 to 10 See also in this result: the core density of the foam obtained is 1 kg / m3) measured according to ASTM 3 574 / A; the maximum possible foam to a 0.9% NaCl aqueous solution (physiological liquid) Absorption (grams of solution absorbed per cubic inch of foam); Foam containing the solution measured in the above amount was applied for 15 minutes at a pressure of 1 psi (4.5 kg / 64 cm2), and then The amount of solution remaining in the foam and measured, and calculated according to the following formula: (Am- Ap) x 100 100 ----%

Am is the maximum absorbable amount of the foam to the solution, and Ap is the amount of the solution remaining in the foam after the pressure is applied. The pressure is applied after the foam is held for 1, 10, 20 or 30 minutes. Table 5 shows the residual rate at the optimal holding time. The measurement of the maximum absorption amount was performed in the foaming "I dried at room temperature for 24 hours, the foam was completely immersed in the solution for 15 seconds, and then the foam was taken out of the solution 'and then the foam per cubic inch was measured. The weight difference of the body before and after immersion was repeated. The above experiment was repeated once with 22 C of water. The results obtained are shown in Table 5. Experiment 11 + 12 (hold for 30 minutes). -22- This paper size is applicable to China National Standards (CNS) A4 (2l0X297) (Please read the note on the back before filling this page) -0- * π

7 7 AB V. Description of the invention (20) Table 5 Experimental SAP type / SAP usage maximum absorption, grams / cubic inch retention rate / min file retention time minutes nuclear density, kg / cubic meter 1-1370 53 / 1- 30 65 2 1/15 1470 61 / 1-10 96 3 1/30 1350 57 / 1-10 99 4 1/50 1280 79/20 133 5 2/15 1240 67/10 90 6 2/30 1410 95/10 105 7 2/50 990 98/30 102 8 3/15 1480 64/10 80 9 3/30 1330 71/10 102 10 3/50 -1250 99/10 128 11 1/50 (water temperature = 22 ° C) 1460 97 154 12 2/30 (water temperature = 22 ° C) 1360 94 124 Printed by the Central Labor Bureau of the Ministry of Economic Affairs, Shellfish Consumer Cooperatives (please read the precautions on the back before filling this page) SAP Type 1: Polypropylene 醯Amine-based SAP with a molecular weight of about 5.106

2: Starch-grafted polyacrylate sodium salt, SANWET IM 7000 °

3: Polypropionate sodium salt SANWET IM 3900G -23-_ This paper size is applicable to China National Standards (CNS) A4 (210X297 mm), Central Government Bureau of the Ministry of Economic Affairs, Confucian Labor and Consumer Cooperation, Du printed installation invention description (21 Implementation Example 4 Experiment 4 in Example 3 was repeated, but SAP was added from each question with Bu Gu Shi # l Λ 1. The obtained foam was run slightly to visually detect whether the obtained foam was an open cell foam. The shrinkage of foam and foam is measured according to the following formula:

(Sb-SJxlOO%

Sb is very medium * Sb is the diameter of the cup from which the foam is made, and Sa is the diameter obtained after the foam is held at room temperature for 12 hours. The results are shown in Table 6. Experiments 1 to 5 »Table 6 Experimental SAP addition method Open cell shrinkage 1 was added to water, immediately followed by prepolymer non 18 2 was added to water, then prepolymer was added, after 150 seconds Add prepolymer non-65 3 to prepolymer, immediately followed by water is 14 4 added to prepolymer, 150 seconds after adding water is 13 5 SAP, prepolymer, water is added together 13 6 + 7 t to prepolymer Polymer, adding water after 2 hours is 13 and repeating experiment 4, but adding water after 150 seconds, and after 2 hours, and 24- This paper size applies to China National Standard (CNS) A4 (210X297 mm)- --------- ά ------ ΐτ -------- 9 (Please read the note ^^ on the back before filling this page) A7 _B7_ V. Description of the invention (22) The usage of SANWET IM 7000 and SANWET IM 3900G is 30 pbw. The results are shown in Table 6, Experiment 6 + 7. Example 5 (comparative) Experiment 3 of Example 3 was repeated, but 5 pbw of water was used. Foam disintegration (please read the precautions on the back before filling out this page) Printed by the Central Consumers ’Bureau of the Ministry of Economic Affairs and Consumer Cooperatives -25- This paper size applies to China ’s National Standards (CNS) A4 (210X297 mm) )

Claims (1)

Gong ^ 841 ^ 4 patent application is successful! Lifan Group 倏 five big 4 years 六 6, patent application Fan Gunian ((ν S842d4 Central Ministry of Economic Affairs, Central Bureau of the Ministry of Work, Consumer Work Cooperatives, Printing 1, a kind of Method for reacting polymer and water to produce flexible foam, the prepolymer has an NCO value of 3 to 15 weight percent, which is obtained by using an excess of polyisocyanate and polyether polyenzyme or a mixture of such polyunsaturated alcohols The reaction product, the polyhydric alcohol or mixture has an average hydroxyl-like functional group of 2 to 6, an average hydroxyl equivalent of 500 to 5000, and an acetic acid content of at least 50 weight percent; the amount of water used is 100 parts The prepolymer weighs 15 to 500 parts of water; the reaction begins ^ The temperature of the deep polymer is 10 to 50 ° C, and the water temperature is 10 to 50 ° C higher than the temperature of the prepolymer. 2. According to the scope of patent application Item 1 A method for preparing a flexible foam, wherein the water temperature is 25 to 90 ° C at the beginning of the reaction. 3. The method according to item 1 or 2 of the patent application range, wherein the temperature of the prepolymer is 15 to 30 ° C, water temperature is 40 to 70 eC, and the water temperature is higher than the prepolymerization The temperature of the material is 20 to 45 ° C. 4. The method according to item 1 or 2 of the patent application range, wherein the prepolymer is a prepolymer having an NCO value of 3 to 10% by weight, which is obtained by passing excess polyisocyanate and poly A reaction product obtained by the reaction of a yeast or a polyol mixture. The polyisocyanate contains at least 65% by weight of 4,4 · -diphenyl, methane diisocyanate or a variant thereof, and the polyol or a mixture thereof has an average rated carboxyl functionality. It is 2.5 to 3.5, the average hydroxyl equivalent is 1000 to 3000, the content of acetic oxide is 50 to 85 weight percent, and the water-use amount is 30 to 300 parts by weight per 100 parts of prepolymer. 5. According to method 1 or 2 of the patent application park, where the reaction of the prepolymer and water is 0.01 to 10 parts by weight (per 100 parts of prepolymer weight), the paper scale is used in China Standard (CNS) A4 Specification (210X297mm) ------------- ir ----- (Please read the note on the back before filling this page) A8 BS C8 D8 d84294 Apply Patents range from 500 to 10,000 average molecular weights and average rated hydroxyl functionality 2-6 is performed in the presence of polyenzyme (2). The polyenzyme is a polyethylene oxide polycryl oxide or a polyethylene oxide polypropylene oxide copolymer, which has an ethylene oxide content of at least: 30% by weight. 6. The method according to item 5 of the scope of the patent application, wherein the polyzyme (2) has an average rated functional group degree of 2 ′ and an ethylene oxide content of 35-70% by weight. 7. According to the patent application The method according to item 5, wherein the polyhydric (2) has an ethylene oxide content of at least 70% by weight, and the water is used in an amount of at least 40 parts by weight per 100 parts by weight of the prepolymer. 8. The method according to item 1 or 2 of the scope of the patent application, wherein the reaction between the prepolymer and water is performed in the presence of a superabsorbent polymer, 9. The method according to item 8 of the patent application range, wherein the superabsorbency The polymer is used in an amount of 100 parts by weight of the pre-polymer and 10 to 70 parts by weight of the superabsorbent polymer. 10. The method according to item 8 of the patent application, wherein the superabsorbent polymer is selected from superabsorbents based on acrylic or methacrylic acid, esters, nitriles, amidines, and / or salts thereof. Polymers; superabsorbent polymers based on sugars and superabsorbent polymers based on maleic anhydride. 11. —A method for preparing a flexible foam by using a prepolymer and water reaction ', characterized in that the reaction of the prepolymer and water is performed in the presence of a superabsorbent prepolymer; the prepolymer has 3 to NCO value of 10% by weight 'is based on the use of excess polyisocyanate and polybond polyenzyme or -2 ---------, (please read llq on the back before filling out this page) Order · Printed paper of the printed paper ΛΑ by the Central Standards Bureau of the Ministry of Economic Affairs β_ 家 椟 准 (CNS) (2 like 297) Α8 Β8 C8 D8 384234 VI. Apply for a patent to fix this kind of polyol The reaction product obtained by the reaction of the mixture; the polyisocyanate contains at least 65% by weight of 4,4, -diphenylmethane diisocyanate or. Its variation is more. Ping Ling rated several groups of functional groups of 2.5 to 3.5 'average hydroxyl equivalent of 1000 to 3,000, oxidized women content of 50 to 85 weight percent; the amount of water used per 100 parts of prepolymer weight 30 to 300 parts by weight "12. According to the method of the patent application, item ^, the reaction between a certain prepolymer and water is 0.01 to 10 parts by weight (per 100 parts by weight of the prepolymer), a polyenzyme having an average molecular weight of 500 to loooo 'and an average rated functional functionality of 2 to 6 (2) > The polyenzyme is a polyethylene oxide polymer or a polyethylene oxide polypropylene oxide block copolymer, which has an ethylene oxide content of at least 30% by weight. 13. The method according to item 12 of the scope of patent application, wherein the amount of the polyol (2) is 0.05 to 3 parts by weight per 100 parts of the prepolymer. 14. The method according to item 12 or 13 of the scope of patent application, wherein the polyol (2) has an average rated hydroxy functionality of 2 and an ethylene oxide content of 35 to 70% by weight. 15. The method according to item 12 or 13 of the patent application group, wherein the polyol has an ethylene oxide content of at least 70% by weight and the amount of water used is ′ per 100 parts by weight of the prepolymer and at least 40 parts by weight of water. 16_ Method according to item u, 12 or 13 of the scope of patent application, wherein the amount of superabsorbent polymer used is per 100 parts of prepolymer weight and 10 to 70 parts of test absorbent polymer weighs β 17. According to patent application Fan Yuan's method of item 11, 12 or 13, in which the superabsorption -3- paper ft scale is applicable to China National Standard (CNS) A4 specification (210X297 male shame) (please read the "$" on the back and then the t Page) Order printed by the Ministry of Economic Affairs and the Central Government Consumer Cooperative Cooperative, printed by the Central Standards Bureau of the Ministry of Economic Affairs, printed by 384294 I D8, and applied for patents. The polymer is selected from acrylic or methacrylic acid, Superabsorbent polymers based on esters, nitriles, amidines and / or their salts; superabsorbent polymers based on doxyl; and based on cis-butadiene anhydride Super 'absorbent polymer. 18. A composition comprising a prepolymer and a superabsorbent polymer, the towel prepolymer has an NCO value of 3 to 5 weight percent, which is a polyisocyanate and polymer Enigma polyenzyme or the reaction product of a mixture of such polyenzymes; the polyenzyme or mixture has an average rated hydroxyl functionality of 2 to 6, an average hydroxyl equivalent of 500 to 5000, and an ethylene oxide content of at least 50 weight percent . 19. The winter composition according to claim 18 of the patent application, wherein the polyisocyanate contains 1-at least 65%. 4,4'-diphenyl Tane diisocyanate or a variant thereof. 20. The group + according to claim 18 or claim 19, wherein the prepolymer is a prepolymer having 3 to 10 weight percent, which is obtained by using a mixture of excess polyisocyanate and a polyvalent enzyme or a polyhydric alcohol to react Reaction product; the polyisocyanate contains at least 65% by weight of 4,4r-diphenylmethane diisoester or a variant thereof; the functional degree is 2.5 to 3.5, and the average equivalent weight is 1000 to 3000; ethylene oxide The content is 50 to 85 weight percent. 21. The composition according to claim 18 or 19, wherein the superabsorbent polymer is present in an amount of 100 parts by weight of prepolymer and 10 to 70 parts by weight of superabsorbent polymer. 22. The composition according to item 18 or 19 of the patent application park, where the superabsorbent polymer is selected from acrylic acid or methacrylic acid, esters, nitriles, and fluorene (please read the note on the back first) f. Please fill in this page again) Order _ 1 4 · This paper towel «head home material (CNS) Α4ΛΛ · (21GX297 mm): 384294 A8 S _______D8 ___ VI. Patent application group amines and / or M type Based on superabsorbent polymers; polyacoustic based superabsorbent polymers and maleic anhydride based absorbent polymers. 23. An absorbent article comprising a catalyst-free, hydrophilic polyaminomethacrylic flexible foamed skeleton made from a prepolymer and a superabsorbent polymer in the composition in the 18th aspect of the patent application, The foaming ceremony is based on diphenylmethane diisocyanate, and has a core density of at most 154Kg / m3, and the first three do not have a single, di- or more that can be released in contact with water or an aqueous solution. ---- ^ (Please read the note f on the back before filling in this purchase) Printed by Zhenong Consumer Cooperative, Central Government Standards Bureau of the Ministry of Economic Affairs of the People's Republic of China «. This paper standard uses" I »country national approval (CNS) A4 Specifications (210X297 mm) The patent application No. ^ 841 ^^ 4 is successful! · Lifan Group 倏 Five Big 4 Years 六 6. Applying for a Patent Fan Gunian ((ν S842d4 Printed by the Central Government Bureau of the Ministry of Interest and Economics and Consumer Cooperatives) Pack 1, a method for preparing a flexible foam by reacting a prepolymer with water, the prepolymer having a NCO value of 3 to 15 weight percent, which is based on the use of excess polyisocyanate and polyether polyenzyme or such A reaction product obtained by the reaction of a polyhydric alcohol mixture, the polyhydric alcohol or mixture having The average hydroxyl-like functionality is 2 to 6, the average hydroxyl equivalent is 500 to 5000, and the content of acetamidine is at least 50% by weight; the amount of water used is 15 to 500 parts by weight per 100 parts of prepolymer The reaction starts ^ The temperature of the deep polymer housing is 10 to 50 ° C, and the water temperature is 10 to 50 ° C higher than the temperature of the prepolymer. 2. According to the first patent application scope, the flexible foam is prepared. Method, wherein the water temperature is 25 to 90 ° C at the beginning of the reaction. 3. The method according to item 1 or 2 of the patent application scope, wherein the temperature of the prepolymer is 15 to 30 ° C and the water temperature is 40 to 70 eC, and the water temperature is 20 to 45 ° C higher than the temperature of the prepolymer. 4. The method according to item 1 or 2 of the patent application scope, wherein the prepolymer is a prepolymer having an NCO value of 3 to 10% by weight The polyisocyanate is a reaction product obtained by reacting an excess of polyisocyanate with a polyenzyme or a polyol mixture. The polyisocyanate contains at least 65% by weight of 4,4 · -diphenyl, methane diisocyanate or a variant thereof. Or a mixture thereof having an average nominal carboxyl functionality of 2.5 to 3.5, The average hydroxyl equivalent is 1000 to 3000, the content of acetic oxide is 50 to 85 weight percent, and the amount of water used is 30 to 300 parts by weight per 100 parts of prepolymer. 5. According to the first patent application Or the method of item 2, wherein the reaction between the prepolymer and water is 0.01 to 10 parts by weight (per 100 parts of prepolymer weight), and this paper is used in accordance with China Standards (CNS) A4 ( 210X297 mm) ------------- ir ----- (Please read the note on the back before filling in this page)