MXPA96004732A - Superabsorbent polymers and losmis products - Google Patents

Abstract

The present invention relates to a superabsorbent polymer, having an AUL value at 0.04218 kg / cm2 of at least 25 g / g at a centrifugal retention value of at least 35 g / g, said superabsorbent polymer being characterized by being the product of a process comprising dispersing an aqueous solution of C3-C6 diol and an interlacing compound having at least two functional reactive groups in a partially neutralizing carboxyl or carboxylate group base interlaced polymer having a AUL value at 0.02109 kg / cm2 of 15 g / g or less, and heat said dispersion to entangle said polymer, wherein said aqueous solution has a surface tension no greater than about 55 dynes per

Description

POLYMERS SUPER-HEAVENS AND PRODUCTS THEREOF BACKGROUND OF THE INVENTION TECHNICAL STAGE This invention is directed to improved aqueous fluid absorbent polymers as a process for s? manufacture and absorbent articles made therefrom. In particular, the invention is directed to superabsorbent polymers that have improved fluid absorption properties, which provide superior performance when incorporated into absorbent articles.

BACKGROUND The present invention is directed to high molecular weight, water-insoluble insoluble polymers that can absorb and retain large amounts of aqueous fluids. These polymers are well known in the art by various names such as superabsorbent polymers, hydrogels, hydrocolloids, hydrophilic polymers, u absorbers, etc. For the purpose of this description, the term "polnnero (s) suμerabsorben + e (s)" is used to describe said1, materi les. Illustrative superabsorbent polymers are crosslinked, partially neutralized polyacrylic acid (see U.S. Patent No. 4,654,039), an enriched, partially neutralized acrylic-acid starch graft polymer (U.S. Patent No. 4,076,663) , an interlaced, partially neutralized copolymer of isobutyl ether and maleic anhydride (U.S. Patent No. 4,389,513), a saponification product of vinyl acetate-acrylic acid copolymer (U.S. Patent No. 4,124,748), an acrylamide polymer hydrolyzate or acrylarnide copolymer (US Patent No. 3,959,569) or a hydrolyzate of an acplomethyl copolymer (US Patent No. 3, 935, 099). The teachings of the above patents are incorporated herein by reference. The superabsorbent polymers are used in many - fluid absorption applications, the main use in the field of personal care products such as diapers, sanitary napkins, incontinence products for "Adults, absorption pads for medical uses, The largest market for superabsorbent polymers is found in disposable baby diapers, eg, US patents Nos. 3,669,103; 3,670,731 or 4,654,039." Super absorbent polymers are prepared polunerizing a substantially saturated ethylene or an alkali metal salt of said monomers or mixtures of the same and forming the polymer either during and / or after polymerization. Preferably, the ethylene-unsaturated ethylene monomer is soluble in water However, it is possible to use rnonordens which become water-soluble by hydrolysis Illustrative water-soluble monomers are those containing carboxyl groups, carboxylic acid anhydride groups, carboxylic acid salt groups, sulphonic acid groups, sulfonic acid salt groups , Lyo hydroxyl groups, amido groups, amino groups and quaternary ammonium salt groups. two is found in the patent of E.U.fl. No. 4,076,663 in column 2, lines 6-68 and column 3, lines 1-12; whose teachings are incorporated here by reference. In case the monomer is a monomer having an acid group, the monomer may be partially neutralized before the polymerization or the polymer may be neutralized subsequent to polymerization with an alkali metal such as sodium or potassium or a compound such As an ammonium hydroxide, the monomer may also be polymerized in the presence of preformed polymer to produce a graft polymer. Exemplary preformed polymers are starch, polyvinyl alcohol, carboxymethyl cellulose and other polymers. Some methods are described in the literature and are well known for the preparation of superabsorbent polymers. Generally, these methods involve some variant of an aqueous solution polymerization method or a reverse suspension polymerization method. The patent of E.U.fl. No. 5,145,906 illustrates the solution polymerization method; and the patent of E.U.fl. Do not. 4,666,975, the reverse suspension method. Polymers made by any of these methods can be used in this invention. The literature contains many examples and attempts to improve the performance of superabsorbent polymers in absorbent articles. The patent of E.U.fl. No. 32,649 claims that polymers of low extractable content, high gel strength and high gel volume will give improved performance. The patent of E.U.fl. No. 5,147,343 discloses an absorbent article composed of a fibrous matrix having a superabsorbent polymer of AUL (absorbency under load) which has improved performance properties; that is, less drainage in diapers. This performance correlation of FLUL is described more fully in the scientific literature, see, eg, "The Concept of Superabsorbent Polyrner" by Dr. F. Mas? Da, Pira Fibranetrics Program, Paper 13 (Dec. 1987). ). Another example is the patent of E.U.fl. No. 5,145,906 which discloses improved performance using a superabsorbent polymer having certain minimum polymer properties. A known technique for preparing superabsorbent polymers having improved performance properties is to interlace the surface of the polymer particle with a back interlacing treatment. The interlacing of the polymer chains on the surface of the superabsorbent particles reduces the tendency of the particles to block and agglomerate with gel when wetted with an aqueous liquid. Gel blocking is a reduction in the fluid absorption capacity produced by the formation of gel on the surface of the polymer particles which blocks the transfer of fluid from the polymer surface therein. This gel can also cause the polymer particles to agglomerate, which also reduces the ability of fluid to absorb. Several patents of the prior art describe the post-treatment of superabsorbent particles for interlacing the polyrnery chains on the surface in the vicinity or near the surface of the particles, and these teachings are illustrated below. The patent of E.U.fl. No. 4,666,983 describes the surface entanglement of a superabsorbent polymer using 0.001 to 10 parts by weight of a functional interlacing agent. The patent does not disclose the use of any vehicle solvent for the interleaver. Such crosslinking agents are widely described such as polyhydric alcohols, polyglycidyl ethers, polyfunctional amines and polyfunctional isocyanates. The patents of E.U.fl. Nos. 4,507,438 and 4,541,071 disclose the surface relaxation of a superabsorbent polymer with a di functional compound (a crosslinker) in the presence of 0.01 to 1.3 parts by weight of water and 0.1 to 50 parts by weight of an inert solvent. 100 deliveries < polymer The interlayer may be present in amounts of from 0.005 to 5% by weight. The patents disclose the use of a wide class of crosslinking agents including glycidyl ethers, halogenoepoxides, aldehydes and isocyanates with ethylene glycol diglycidyl ether being the preferred interleaver. A multitude of mntert solvents are described as being useful in the invention. Solvents include polyhydric alcohols with ethylene glycol, propylene glycol and glycerin listed as preferred polyhydric alcohols. A mixed solvent system is used to control the penetration of the interlayer - inside the particles. It is taught that the use of 1.3 parts by weight and less than 0.1 parts of inert solvent by part of superabsorbent polymer is undesirable. The patent of E.U.fl. No. 5,140,076 describes surface entanglement using a solvent which comprises 0-50% water and 0-60% solvent. The reaction is conducted in a high speed mixer in the liner, where the liner is required to have a certain contact angle. The patent describes the use of polyhydric alcohol, diglycidyl ether, polyapzidene, urea, amine and ionic crosslinkers. The patent of E.U.fl. No. 5,164,459 discloses a very similar surface entanglement method - to the '459 patent described above using a polyhydric alcohol as an interlayer. The reaction is carried out according to a specific equation to interlock the surface of the ream and produce desired properties. EPO 0 509,708 describes surface entanglement of a superabsorbent polymer with a polyhydroxy compound using a water-based coating solution which may contain a nonionic surfactant and optionally a water-soluble solvent. The description procedure is said to provide a superabsorbent having high absorption capacities, low extractable elements and high gel firmness. The patent application of E.U.fl. No. 08/002346 filed January 6, 1993 discloses a surface interlacing method in which a mixed water / solvent system is used. The solvent is selected from an alkylene oxide of a monofunctional alcohol, a salt of an organic acid and a lactam. A wide class of interleavers is disclosed including polyanino-polyamide epichlorohydrin interlayers. The patent of E.U.fl. No. 4,666,975 discloses an improved superabsorbent polymer which has a salt absorption amount of 40-90 g per gram of polymer, an absorption speed of at least 8 ml per 0.3 g of polymer and a gel strength of 33 to 200 g / cm2. It is said that the superabsorbent polymer possesses an entanglement density gradient in the polymer particles wherein the interlacing density is higher at the polymer particle surface than inside the particle. The patent of E.U.fl. No. 5,002,986 describes the surface agglomeration and interlacing of particular fine sorbsorbents (<300 microns) to provide a superabsorbent polymer composition that has a high absorbency rate. The patent of E.U.fl. No. 5,229,466 discloses a surface crosslinking superabsorbent polymer that uses an aqueous solution of an N- (hydroxyalkyl) (3- (meth) alanine ester and a water miscible organic diluent. the intertwining of ~ surface of p > superabsorbent oligore are the patents of E.U.fl. Nos. 3,202,731; 4,043,952; 4,127,944; 4,159,260; 4,251,643; 4,272,514; 4, 289, 814; 4,295,987; 4,500,670; 4,587,308; 4,732,968M 4,735,987; 4,755,560; 4,755,562; 4,758,617; 4,771,105; 4,820,773; 4,824,901; 4,954,562; - 4,973,632; 4,985,518; 5,026,800. This invention is directed to improved superabsorbent polyrnomer compositions, a process for their preparation and absorbent articles made from said compositions. The process of the invention provides a superabsorbent polymer with superior fluid absorption capacity, low friction absorbency, high gel strength and low extractable elements.

BRIEF DESCRIPTION OF THE INVENTION The invention is improved superabsorbent polymers having absorbency (higher fluid, a process for their preparation and absorbent articles made from them) The superabsorbent polymers of the invention have high fluid absorption capacity, high absorbency under load, low gel block, low dust content and provide absorbent articles having improved dryness and low draining properties The solid absorbing polymers of this invention have an absorbency value under load (AUL) at 0.42 kg / crn2 of at least 20 g / g, preferably at least about 25 g / g and a centrifugal retention value of at least about 35 g / g.These superabsorbent polymers show improved dryness and less drainage when incorporated into absorbent articles such as diapers The improved superabsorbent polymers of the invention are prepared from a base polymer that is a partially neutralized, slightly entangled polymerization product of a carboxyl or carboxyl group mononer or an carboxylic acid anhydride group onornero wherein said polyrneized monomer is present in an amount of about 50 to about 99.5% molar .. The preferred carboxyl group containing rnonornero is acrylic acid. The base polymer is slightly interlaced as evidenced by an absorbance under load at .021 k / crn2 of 15 g / g or less, a centrifugal holding property (CRFT) of at least 35 g / g, preferably 40 g / g or more. , and a free polymer content of less than 10%. In accordance with the process of the invention, the base polymer polymer is entangled on the surface with an aqueous interlayer solution comprising water, a diol selected from a diol of C3 to Ce and a crosslinker composition. The water and diol components of the interlacing solution comprise from about 1.0 to about 6.0% by weight based on the weight of the base polymer, preferably from about 1.5 to about 5.5% and the surface tension of the interlacing solution should be less than about 55 dynes per cm. The crosslinker compound is selected from organic compounds containing 2 or more groups that can react with the carboxy or carboxylate groups of the polymer and are used in an amount of from about 0.001 to about 3, preferably from about 0.1 to about 1.0% in weight based on the weight of the polymer. Illustrative surface crosslinkers are compounds containing epoxy, epichlorohydrin, aziridinyl and azetidinium groups; preferably the interlayer has a molecular weight of at least 700. The interlacing solution is uniformly mixed on the surface of the superabsorbent particles and the mixture is heated to entangle the polymer chains on or in the surface interfaces of the fibers. particles surfaces.

DESCRIPTION OF THE PREFERRED MODALITIES The ability of a superabsorbent polymer to absorb aqueous fluids generally decreases as the load or pressure on the polymer increases. The superabsorbent polymers of this invention have an absorbency value under load (AUL) at .042 kg / cm2 of at least 20 g / g, preferably 25 or more and a centrifugal retention value of at least about 35 g / g. The superabsorbent polymers having an AUL value at .042 kg / cm2 of 20 g / g will show an AUL at 0.021 kg / cm2 of 30 g / g or more. In a preferred embodiment of this invention, the superabsorbent polymers will have an AUL at 0.021 g / cm2 in excess of 30 g / g and an AUL value at 0.42 kg / cm2 of 25 or more. These polymers show improved dryness and poor drainage when incorporated into absorbent particles such as diapers. The superabsorbent polymers of this invention are prepared from monomers containing carboxylic acid or carboxyl acid anhydride of water soluble, unsaturated and unsaturated rnonoet and the salts of ?? i >such an alkali of ammonium thereof where said monomers comprise from 50 to 99.9 mol% of said polymer. Exemplary monorneros include acrylic acid, rnetacrylic acid, maleic acid, furnapco acid, maleic anhydride and sodium, potassium and ammonium salts of the same. The preferred rnonomer is acrylic acid. A base polymer is prepared from said water-soluble monomers to provide a slightly neutralized, partially neutralized superabsorbent polymer having an aqueous fluid absorption capacity as illustrated by the high centrifugal retention properties. The definition of polymer properties * - superabsorbent used herein and the applicable test methods are set forth in the test method section of the description and the examples. The base polymer useful in this invention is characterized by the following properties. Absorbency under load & 0.021 kg / cm2 < 15 g / g Centrifugal retention > 35 g / g Removable content < 10% (weight) The monoethylenated unsaturated monomers are poly erized in the presence of an internal interlacing compound to provide a lightly entangled base polymer where the interlacing is substantially uniform in all polymer particles. These internal agents are well known in the art. Suitable reactants are those compounds having two or more groups which can react with ethylene-unsaturated monomers and which are soluble in water or soluble in a water-based mixture. The internal interlacing compound may be selected from a poly-unsaturated monomer such as divinylbenzene, a compound having at least two functional groups which are reactive with the unsaturated monoethylene onethylene monomer such as ethylenediarnine, a compound having at least minus one unsaturated bond and at least one reactive functional group such as glycidyl acrylate. Exemplary internal crosslinkers are: tetraalyloxyethane, NN'-rilentilene bisacrylamide, NN '-methyl bisnetacrylamide, tpalylamine, tninetiiol propane triacrylate, glycerol propoxytpacrylate, divinylbenzene, N-metholol acrylamide, N-methylolmethacrylamide, glycidyl ethacrylate, polyethylenepolycarnins, ethyldiarnine , ethyl glycol, glycerin and the like. The preferred internal inter-linkers are those containing at least two alkyl groups, most preferably 4 alkyl groups. A preferred internal interlayer is tetraalyloxyethane. The amount of internal interleaver employed in the invention will depend on the internal interleaver and the polymerization method. Generally, the amount between the internal interleaver will vary from about 0.005% to about 1.0 mole% based on moles of ethically ionized monomer. The optional components used in the preparation of the superabsorbent polymers of this invention are water-soluble hydroxyl group-containing polymers, such as polysaccharides and vinyl polymers or acrylics. Examples of water soluble polysaccharides are starches, celluloses, water soluble and poly galactomannans. Suitable starches include natural starches, such as sweet potato starch, potato starch, wheat starch, starch, rice starch, tapioca starch and the like. Processed or modified starches, such as dialdehyde starch, starch etherified with alkyl starch etherified with starch, oxyalkyl starch, starch etherified with aminoethyl, and starch etherified with cyanomethyl are also suitable. Also suitable are polyvinyl alcohol and polyvinyl alcohol copolymers. Water soluble celluloses useful in this invention are those obtained from sucrose such as wood, stem, bast, seed fluff and the like which are then derivatized to form hydroxyalkyl cellulose, carboxymethyl cellulose, methyl cellulose and the like. Suitable polygalactornanans are guar and locust bean gums, and their hydroxyalkyl, carboxyalkyl, and arninoalkyl derivatives. Water-soluble polyvinyl and acrylic polymers include polyvinyl alcohol and polyhydroxyethyl acrylate. The preferred polysaccharide for use in this invention is natural starch, such as wheat starch, starch, and alpha-starches. These optional preformed hydroxyl-containing polymers can be used in an amount of about 1 to 15%, preferably about 1 to 10%, most preferably about 1 to 5%. The superabsorbent polymers in this invention can be used. Prepare by well-known polymerization methods The polymerization reaction is conducted in the presence of reducing oxide initiators and thermal initiators The reduction oxide initiators can be used as the primary initiator with the thermal polymerization initiators being used if desired reduce the content of free monorneros of the final polymerization product below 0.1% by weight., thermal initiators or oxide-reduction initiators can be used as the sole initiating system. Examples of different initiator systems are found in the US patent. No. 4,497,930 which describes a two-component initiator system comprising a persulfate and a hydroperoxide and a U.S. patent. No. 5,145,906 which describes a component initiator system; that is, a more thermal-initiating oxide-reduction system. Any of the well-known water soluble oxidizing agents and reducing agents can be used in this invention as a reducing oxide initiator. Examples of reducing agents include compounds such as ascorbic acid, alkali metal sulfites, alkali metal bisulfites, ammonium sulfite, ammonium bisulfite, alkali metal sulphite, ammonium acid sulfite, ferrous metal salts, e.g. , ferrous sulfates, sugars, aldehydes, primary and secondary alcohols and sirni lar-es.

Oxidizing agents include such compounds as hydrogen peroxide, alkaline metal persulfate, ammonium per-sulfate, alkylhydroperoxides, peresters, diacrylperoxides, silver salts and the like. A particularly preferred reducing oxide initiator part is ascorbic acid and hydrogen peroxide. The reducing agent is used in an amount of from about 2 x 10-5 to about 2.0 x 10-2 mole percent based on moles of acrylic acid. The amount of oxidizing agent used will vary from about 2. ' x 10-3 to about 1.1 mole%, based on moles of acrylic acid. In order to ensure complete polymerization of an unsaturated monomer and the interlaced monomer, thermal initiator may be included in the polymerization process. Useful thermal initiators are the "azo" initiators, ie, compounds containing the structure -N = N-, any of the azo compounds having solubility in water or in a mixture of onornero-water and having a half-life of 10 hours at 30 ° C or higher can be used. Examples of useful azo initiators are 2,2'-azob? S dihydrochloride (arn? D? No), cyanovaleric acid 4,4'-azob? S, 4,4 '-butylazo-cyanovalent acid, 2,2'? azobisí isobu i ronitrilo), and the like. Other thermal initiators include the persulfates and hydroperoxy when used in the absence of a reducing agent, v.gr., Sodium, potassium and ammonium persulfates, t-butylhydroperoxy or the like. A preferred azo initiator for use in this invention is diclo hydrate of 7.2 'azob? S (a? D? No? Ro? An). The thermal initiators are used in the amount of 0 to about 1 mol% based on the weight of an unsaturated rnonomer. The base polymer can be prepared by the solution or inverse suspension polymerization method or by any suitable mass polymerization method. Preferably, the base polymer is prepared according to the solution polymerization method. Polymerization methods in solution polymerization and reverse polymerization are well known in the art; see for example patents of E.U.fl. No. 4076,663; 4,286,082; 4,654,039 and 5,145,906 which describe the solution polymerization method and patents of E.U.fl. Nos. 4,340,706; 4,497,930; 4,666,975; 4,507,438 and 4,683,274 describing the reverse suspension method. The teachings of these patents are incorporated herein by reference. In the solution polymerization method, the water-soluble monomer is polyered at a rnonomer concentration of about 5 to about 30% in aqueous solution at a temperature of about 5 ° C to about 150 ° C depending on the system polymerization initiator. A detailed description of the solution polymerization method is given in the patent of E.U.fl. No. 5,145,906; whose teachings are incorporated here by reference. In the reverse suspension polymerization process, the monomer that is saturated in an aqueous solution (approximately 35 to 60% rnonomer at 65 to 40% water) is dispersed in an aliphatic or alicyclic hydrocarbon suspension medium in the presence of an agent dispersant such as a surfactant or protective colloid such as polyvinyl alcohol. A surfactant having an HLB value of 8 to 12 such as sorbitan fatty acid ester can be employed as the dispersing agent. The polymerization and reverse suspension method is described in detail in the U.S. Patent. No. 4,340,706; whose teachings are incorporated here by reference. The carboxylic acid groups of the unsaturated monomer used in the polymerization have been partially neutralized. Suitable neutralizing agents include an alkali such as sodium hydroxide, ammonium hydroxide, potassium hydroxide or the like, and the appropriate degree of neutralization is 50-98% molar, preferably 60-75%. the degree of "Neutralization must be at least 50% molar.

"Low neutralization (less than 50 mol%) gives s? Perabsorbent polymers that have low absorbency properties. The base polymer is prepared either by the solution or inverse polymerization method, it is dried and sifted to provide a superabsorbent particle with an appropriate particle size distribution and an appropriate particle ion confi uration. Generally, the superabsorbent particle size distribution should be between 100 and 850 microns, preferably between 150 and 600 microns. Large particles above 850 microns are not desired since they do not always feed well on the machine used to make absorbent articles; they tend to make the absorbent article feel abrasive and do not work well from an absorption efficiency point of view. Small fine particles less than 100 microns are not desired since they block gel. Particles smaller than 10 microns are not desired because they form dust and present a problem of industrial hygiene. Surprisingly the products of this invention have a low tendency to form dust as evidenced by their counting of particles in the low air. Air particles are not desired from an industrial hygiene point of view because they can be inhaled or breathed by workers in manufacturing operations and produce irritation in the lungs. The base superabsorbent polymer is treated with an interlayer solution containing from about 0.5 to about 3.5% by weight of water, from about 1.0 to 2.5% by weight of solvent iscible in water selected from a diol of C3 to Ce and a interleaver which has at least two functional groups which can be reacted with the carboxyl, carboxylate groups? other reactive groups in the superabsorbent polymer chain for interlacing the polymer chains or in the vicinity (ie the surface of the polymer particles super-absorbent.es) The term "diol" means an aliphatic dihydroxy compound which may be a linear compound or branched (a glycol) The term "surface interlacing" used in this description and the claims thereof is used to describe this process (eg, entanglement of the polymer chains in or on the imediation of the particle surface. The terms "surface interleaver" and "surface interleaver solution" are likewise used to describe the crosslinking compound and the solution used to effect this surface crosslinking process.The crosslinking compound is used in a quantity of about 0.01 to about 3% by weight, preferably from 0.1% to 1.5% and most preferably from about 0.25% to 1 % based on the weight of the superabsorbent polymer. The surface interleaver may be selected from diglycidyl ethers, allogenoperoxy, isocyanate, aziridinyl, compounds containing an azetidinium group, polyarnine, polyaninated polyarynide, ~ polyamine-epichlorohydrin adducts and arnin-poly-ero-epichlorohydrin adducts and the like. Preferred crosslinkers are the glycidyl ether compounds of higher molecular weight of at least 200 and the polymeric epichlorohydrin adducts having an average molecular weight exceeding 2000. Illustrative surface crosslinkers are diglycidyl polyethylene glycol ethers, diglycidyl ethers. polypropylene glycol, substituted epichlorohydrin compounds, substituted compounds with inethyl-epichlorohydrin, hexamethylene dusocyanate, tolytenetriaran, polyethylenalene, 2, 2-b? sh? drox? rnet? l butanol-tp sC3 - (l-az? d ? n? l) proponatol, polyarynin-epichlorohydrin adducts, polyethylene-polyamine-epichlorohydrin adducts and the like. The preferred surface crosslinkers are the higher molecular weight diglycidyl ether compounds, polyarynide (polyaromide-polyarnine) adducts, ep? CLorh? Dr-ina, polyamine-epichlorohydrin adducts, and polynuclear adducts. -epiclorhidpna. The polyarnide-epichlorohydrin adducts are prepared by reacting epichlorohydrin with the polycondensation product of a polyalkylene polyamine with a polyboxylic acid such as diethiitriamine with a dibasic acid such as adipic acid. The epichlorohydrin and polyamine adducts are made by condensing a polyalkylene polyamine directly with epichlorohydrin.

These adducts include polyalkylene polyamines which are * - interlinked with dihalogenides to form higher polyesters before reacting them with epichlorohydrin. The adducts of a polymer-epichlorohydrin include resins in which the polyarnary amine is polymerized to a polyarynin precursor which is then alkylated and reacted with epi clorhi dpna. They include polymers substituted with amines of vinyl monomers, aillo, acplato or epoxi. The adducts of epichlorhydrin either the polymer is poly-knotted, a polyamide or an amine polymer reacts with the epichlorohydrin in different ways. Without the anino group n 97 Polymer chain is a primary amine, two molecules epichlorohydrin are reacted with nitrogen and form an amino group substituted with chloro disubstituted hLdroxypropyl. The secondary amine groups react with epichlorohydrin to form a tertiary ammochlorohydrin group which is cyclized to form a 3-h? Droxazet? Din? Or reactive salt portion. This is a preferred reactive group. The tertiary amine groups react with epichlorohydrin for a glycidyl; salt of (2,3 epoxy pr-opyl) arnon? o. Preferably, the reactive group is an azetidinium position. However, these adducts may contain a mixture of chlorohydroxypropyl epoxy and azetidyl groups. Preferably, the epichlorohydrin adducts have a molecular weight of at least 2,000, preferably 300,000 to 500,000 and at least 50 mol% of the reactive groups in the adduct are the azetidium group. A preferred polymer is one in which about 90% of the substitution is in the form of an azetidinium group and about 10% as an epoxide group. Illustrative products are epichlorohydrin adducts Reten "204LS and Kymeme" 736, available from Lbles from Hercules Inc., Uilrnington, Delaware. These products are sold as an aqueous solution of the reactive epichlorohydrin adduct, the product Reten "204L is available as a 15% aqueous solution and the product Ky? NerneR 736 co or a 38% aqueous solution. it should have a surface tension no greater than about 55 dynes x crn, preferably no greater than about 50 dynes x ein; e.g., of about 40 to about 50 dynes per crn. The surface interlayer solution has a lower absorbency, as evidenced by a low AUL value of .042 kg / crn2, although it is not desired to limit any theory of the interlacing solution to be greater than about 55 dynes per-ein., it is believed that when the surface tension of the interlacing solution is greater than "*" about 55 dynes per cm, the solution is not uniformly distributed over the surface of the polymer particles and a lower absorbency value is obtained. A surfactant can be used to reduce the surface tension of the interlacing solution The desired surface tension is achieved by adding a dihydroxy compound of C3 to Ce to the water component of the interlaced solution a to achieve a surface tension by The amount of each solvent is determined by simple experimentation, generally, the entr-builder has a negligible effect on the surface tension of the interlacing solution The diols useful in the invention are propylene glycol, butylene glycol , pentanediol and hexanediol The ethylene glycol was found to be an undesired solvent since it tends to swell the superabsorbent polymer particles and its super fi cial becomes sticky resulting in unwanted particle agglomeration.Adoles, the ethylene glycol is undesirable due to its toxicity and biodegradability properties The diol from C3 to Ce is used in an amount of about 1% at p> to about 2.5% by weight based on the weight of the superabsorbent polymer, preferably about 1 to about about 2% by weight The water component of the interlayer solution comprises approximately 0.5 to 3.5% by water based on the weight of the po limer, preferably about 1.5 to 2.0%. The total amount of interlacing solution used depends on the type of equipment and the method used to coat the base polymer with the surface interlacing solution. Generally, the amount of interlacing solution should be about 1.5% minimum based on the weight of the polymer. The interlacing solution is applied to the base particles in such a way that the solution is evenly distributed over the surface of the base polymer particle. Any of the known methods for dispensing a liquid can be used; preferably dispersing the interlacing solution in fine droplets; e.g., by using a nozzle under pressure or a rotating disc. The uniform interlayer dispersion on the base polymer can be achieved in a high density mechanical mixer or a fluidized mixture that suspends the base polymer in a turbulent gas stream. The methods for the dispersion of a liquid on the surface of the superabsorbent based polymer < -, are known in the art; see, for example, E.U.fl. 4,734,478; whose teachings are incorporated herein by reference; in particular column 6, line 45 to column 7, line 35. Illustrative commercially available equipment for conducting the dispersion step of the interlacing solution of the invention are high speed variable intensity blade mixers such as a "Turbulizer" mixer. the Bepex Corporation, Rolling Meadows, Illinois; or the high-speed variable intensity vertical mixer sold by Bepex under the trade name "Turboflex". These machines are generally operated in a continuous manner using a short residence time of the order of 2 seconds to 2 minutes, typically 2-30 seconds. The dispersion can be effected intermittently in a high intensity mixer such as a Henschel mixer or in a liquid-solid V mixer equipped with a liquid dispersion device. In either case, whether an intermittent or continuous dispersion method is used, simple experimentation can be conducted to determine the best conditions of the process for the particular machine employed in the process. Preferably, the surface interleaver is coated on the Polymer particles under conditions of high intensity mixing After the dispersion of the surface initiator on the base polymer particle, the reaction in the elastomer is effected and the polymer particle is dried, the interlacing reaction is carried out. It can be carried out at a temperature (around 70 ° C to about 150 ° C).

TEST METHODS The following test methods were used to determine the properties of the p > superabsorbent olimers which are described herein.

Absorbency under one load (AUL) at 2,042 kg / cm2 This test is designed to determine the absorbency under load of a superabsorbent material. The amount of saline solution (0.9% by weight aqueous NaCl solution) absorbed with the pee applied to p >olimer indicates the effectiveness of polymer absorbency in a diaper system under the weight of a baby ». Absorbency under load is measured using a plastic petp box with lifting rods and a plexiglass tube of 3.152 c outside diameter x 2.535 crn inside diameter x 3 cm with a wire mesh (100 mesh) at the bottom of the tube. The particle size of the test samples is between 30 mesh to 50 mesh (passes through 30 mesh and is retained by 50 mesh). A test sample, 0.160 + O.Olg is weighed and recorded as Si. The sample is placed in the plastic tube and spread equally over the wire mesh. A weight of 100 g and a disc are placed in the sample p assembly (polymer sample, tube, disc and weight) is weighed and recorded as Ui. The assembly is then placed in a petp box containing 40 ml of 0.9% aqueous saline. After one hour of absorption, the assembly is removed from the petri dish and the excess saline solution is removed from the bottom. The assembly is p > once again and this value is registered as U2. The absorbance under load (AUL) is equal to (U2-W?) / S? and ee expressed in g / g.

Absorbency under load (AUL) at approximately 0.04218 kg / cm2 Absorbency under load at 0.04218 kg / cm2 is determined in the same way as the absorbency under load at 0.02109 kg / cm described above, except that a weight of 200 grams is used in instead of a weight of 100 grams.

Surface tension A suitable quantity of liquid is transferred into a sample retention cup with a surface tension tension (Fisher Sur-face Tensiornat) Model 21 and then the sample cup is placed in the sample table of the tensiometer. A clean platinum / iridium ring is placed in the calibrated tensioner and the sample table is raised until the non-iridium plati ring is below the surface of the liquid. After the ring has been immersed in the liquid for approximately 30 seconds, the arm is released so that it hangs freely and the reference arm is adjusted to be parallel with the line in the mirror of the tensioner. The reference arm is kept parallel to the line in the mirror by decreasing the sample cup when necessary.When the ring is detached from the liquid surface, the number that is registered in the front meter This is the tensile surface in dynes / crn The measurement is conducted at 23 ° C, repeated three times and the average value is recorded.

Centrifugal holding capacity (CRET) This test is designed to measure the amount of saline retained within a superabsorbent polymer when it is under a specific centrifugal force. Approximately 0.200 gram of super absorbent polymer is placed in a sealable tea bag (7.5 cn x 6.5 cm) and the sealed tea bag. The tea bag and the polymer are immersed in a 0.9% saline solution for 30 minutes and then centrifuged for three minutes at 1600 rpm in a centrifugal diameter of 21.6 cm. The difference in weight before and after the centrifugation is the amount of saline solution absorbed by the polymer gel which is divided by half the weight of the original dry polymer and this value is the centrifugal retention capacity of the polymer expressed in g / g. The following examples illustrate the preparation (Je The superabsorbent polymers of the invention and their preparation. These examples are intended to be illustrative and are not intended to limit the scope of the invention or the claims. In this description (unless otherwise specified) the values in percent are percent by weight and the molecular weight of a polynuclear composite is average molecular weight. The measurements and values of surface tension are made and registered at 23 ° C.

EXAMPLE 1 This example illustrates the preparation of a polymer base having 0.02109 kg / cm 2 of AUL of 15 g / g or less and a centrifugal retention value of 40 g / g. Into a 4 liter reaction vessel under a nitrogen atmosphere are added 816 grams of acrylic acid, 306 grams of a starch solution of 8%, 4.5 grams of tetraliloxyethane and 2840.2 grams of de-mineralized water. The mixture is sprayed with nitrogen and cooled to ICC and 16.32 grams of 0.1% aqueous hydrogen peroxide solution, 12.24 grams of 0.1% aqueous ascorbic acid solution and 4.75 grams of 10% aqueous solution of 2.2 -azob? s arní dinopropanodichlorohydrate are added to the reaction vessel. The polymerization reaction is initiated and the reaction temperature increases to 60 ° C from the heat of the reaction. The reaction is repeated for six hours at 60 ° C. The reaction product is a gel that is broken into pieces. Id match reaction gel is neutralized to approximately 70 percent mole with 656.6 grams of 50 percent aqueous sodium hydroxide. The gel is split three times to blend evenly and neutralize the gel. The gel is then dried in a rotary drum dryer of 150 ° C to 200 ° C and the resulting superabsorbent slit is milled into a powder with the following polymer properties and particle size distribution.

Polymer properties 0.02109 kg / cm2 of AUL 13.0g / g 0.04218 kg / cm2 of flul 6.0g / g CRET 46.2g / g Particle size distribution Normal mesh in E.U.fl. Per hundred or by weight 20 0 30 12 50 44 170 41 325 1 -325 0.3 EXAMPLE 2 A rnezcl dora-V (Jel lab-a liquid-sol-sol, adjusted with a liquid dispersion bar (Patterson-KeLloy Corp., East Stroudsburg, PR, Model number 0131200), was loaded with 1.25 kg of the base polymer of Example 1. l.a 3.1 The mixer began to mix, the liquid dispersion bar was adjusted and a mixture comprising 21.9 g of propylene glycol (Ollin Chemical, Stamford, Connecticut.) and 3.12 g (0.25%) of an arnino-polymer-epichlorohydrin adduct as a solution. at 15% in water (Retain "204LS, Hercules Incorporated, lilrnington, Delaware) were added to the mixer for more than one minute of time The weight of the interlayer solution (propylene glycol, water and amino-polycarbonate adduct - ** ' epichlorohydrin) was 4.25% based on the weight of the polymer and the solution had a surface tension value of 50.7 dynes / crn After adding the interlaced solution, the mixture was continued for 2 minutes, then the polymer was heated to 150 ° C and maintained at 150 ° C for 90 minutes to effect the surface interlacing reaction and dry the polymer.The product had the following properties and particle size distribution: Polymer properties 0 02109 kg / crn2 of AUL 31. 4 0. 04218 kg / crn2 of AUL 26. 9 CRET 35. 8 Particle size distribution Normal mesh of E.U.A. Percent by weight 20 0.14 30 31.5 50 52.4 170 15.8 325 0.2 -325 0.0 EXAMPLE 3 The procedure used in this example is substantially identical to that used in Example 2, but the interlaced concentration was increased to 0.375% (4.69 grams of an ino-poly ero-epichlorohydrin adduct) and 2.125% of water was added to maintain the concentration of interlaced solution equal to that of Example 2. The surface tension of the interlacing of the solution was 49.5 dynes / cn. The product had the following properties: 0 02109 kg / cm2 of flul 32.9 0. 04718 k g / crn2 of AUL 22.0 CRET 38.1 EXAMPLE 4 The procedure used in this example is substantially identical to that used in Example 2, but the interlaced concentration was increased to 0.5% (arnine / polyarne / epichlorohydrin adust) and 2.0% water was added to maintain the amount of the interlaced solution; The same as that of example 2. The surface tension of the interlaced solution was 50.1 dynes / cm. The product had the following properties: 0. 02109 kg / cm2 of AUL 31.5 0.04218 kg / cm2 of AUL 26.3 CRET 35.7 EXAMPLE 5 The procedure used in this example is substantially identical to that used in Example 2, but the interlaced concentration contained 0.97% crosslinking (polyethylene / epichlorohydrin adduct) and 1.59% water was added to maintain the concentration of interlaced solution equal to that of example 2. The surface tension of the interlaced solution was 48.8 dynes / crn. The product had the following properties: 0. 02109 kg / crn2 of AUL 32.4 0.04218 kg / crn2 of AUL 25.5 CRET 36.8 The following table L summarizes the information in examples 1-5. In all the examples, the amount of interlaced solution was 4.25 percent at p > that based on the weight (je polymer and the diol was propylene glycol.

TABLE 1 (Examples 1-5) Ex.% XL% PG% ag? A or 0.02109 0.04218 CRET kg / crn2 AUL kg / cm2 AUL CRET 1 0 0 0 0 13 6 46.2 2 0.25 1.75 2.25 50.7 31.4 26.9 35.8 3 0.375 1.75 2.125 49.5 32.9 22.0 38.1 4 0.50 1.75 2.0 50.1 31.5 26.3 35.7 0 97 1.69 1.59 48.8 32.4 25.5 36.8 XXL =% interlaced,% GP =% propylene glycol, s = surface tension-dynes / cm, AUL = absorbency under load g / g, CRET = centrifugal retention g / g.

EXAMPLE 6 This example is substantially identical to Example 3, but 21.9 g of ethylene glycol (Aldrich Chemical, Milwa? Kee, Wisconsin), were used instead of propylene glycol.

The surface tension of the interlocking solution was 6.6.

The product had the following properties: 0.02109 kg / crn2 of AUL 31.5 0.04218 kg / crn2 of AUL 24.0 CRET 36.0 Although the absorbency properties of the polymer were good, the ethylene glycol caused the polymer particles to swell and the particles will agglomerate into large unwanted particles.

EXAMPLE 7 The procedure used in this example is substantially identical to that used in Example 3, but 21.9 g of 1,3-b-tanediol (Aldrich Chemical, Milwaukee, Wisconsin), were used instead of propylene glycol. The surface tension of the interlaced solution was 50.1 dynes / cm. The product had the following properties: 0.02109 kg / cm2 of AUL 32.8 0.04218 kg / cm2 of AUL 23.5 CRET 38.8 EXAMPLE 8 This example is substantially identical to Example 3, but 21.9 g of 1,5-pentad (Aldrich Chemical, Milwaukee, Uiscons) was used instead of propylene glycol. The surface tension of the embedded solution was 43. The product had the following properties: 0. 02109 kg / crn2 of AUL 11.7 0.04218 dj / cm2 of AUL 20.7 CRET 37 .'-) The following table 2 summarizes the information of examples 6,7 and 8. The information of example 3 is also included for reference. These examples had the following common factor: interlocking solution - 4.25%; Interlaced concentration - 0.375%; Diol concentration - 1.75%; and concentration of water - 2.125%. All percentages are in percent by weight based on polymer weight.

TABLE 2 (Examples 3, 6-8) Ex. Solvent Voltage 0.02109 0.04218 CRET surface kg / cm2 AUL kg / crn2 AUL 3 GP 49.5 32.9 22.0 38.1 6 * GE 61.6 31.5 24.8 36.8 7 BD 50.1 32.8 23.5 38.8 8 PD 43 31.7 20.7 37.9 * = observed agglomeration of excessive particles, GP propylene glycol, GE = ethylene glycol, BD = butanediol, PD pentane-diol.

EXAMPLE 9 The procedure used in this example is substantially identical to that used in Example 3, but the interleaved solution contained 40.63 g of propylene glycol (3.25%); 4.75g (0.38%) of adduct of polymeric arnine -epiclorohydpna (Kyrnerne "736; Hercules Incorpor-ated, Wilrnington, DE; 38% solution in water), 7.75g (0.62% 9 (Water je.) The amount of interlaced solution was 4.25 weight percent based on polymer and had a surface tension of 42.7.The product had the following properties: 0.02109 kg / cm2 of AUL 33.2 0.04218 kg / cm2 of AUL 20.6 CRET 38.8 The procedure for this example is substantially identical to that used in example 9, but the amount of propylene glycol was decreased to 18.8g (1.5%). The interlaced solution was 2.5 weight percent based on polymer and had a surface tension of 44.3. The product had the following properties: 0.02109 kg / cm2 of AUL 33.2 0.04218 kg / crn2 of AUL 28.2 CRET 36.0 EXAMPLE 11 The procedure for this example is substantially identical to the one used in example 9, but the amount of prop i lengl icol was decreased to l? .5g (1.0%). The interlaced solution was 7.0 percent by weight based on polymer and had a surface tension of 16.7. The product had the following properties: 0. 02109 k g / crn2 of AUL 34. 6 0. 04218 k g / cm2 of AUL 20. 9 CRET 37 6 EXAMPLE 12 The procedure for this example was substantially identical to that used in example 9, but the amount of propylene glycol was reduced to 6.25 g '- (0.5%). The amount of interlaced solution was 1.5% by weight of polymer and had a surface tension of 50.2. The product had the following properties: * 0.02109 Kg / crn2 of AUL 34 0.04218 kg / cm2 of AUL 16 CRET 41 Table 3 summarizes the information from examples 9-12. In these examples, the amount of interleaver and water remained constant at 0.38% and 0.62% respectively. The amount of propylene glycol was progressively reduced. At a propylene glycol level of less than 1.0 by weight, 0.04218 kg / cm2 decreased to 16 g / g.

TABLE 3 (Examples 9-12) Ex.% GP% XL of s 0.02109 kg / cm2 0.04218 kg / crn2 CRET solution of AUL of AUL 9 3.25 4.25 42.7 33.2 20.6 38.8 1.5 2.5 44.3 33.2 28.2 36.0 11 1.0 2.0 46.2 34.6 28.9 37.6 1122 00..55 11..55 5500..22 34.0 16.0 41.0 % GP =% of propylene glycol,% XL =% of interlaced solution, s = surface tension - dynes / cm, AUL = absorbency under load g / g, CRET = centrifugal retention g / g.

EXAMPLES 13-15 The procedure of Example 3 was repeated, except that the propylene glycol was progressively reduced from 1.0% to 0. 5% to 0%, while the amount of interlaced solution remained at 4.25%. Table 4 summarizes the results of those experiments.

TABLE 4 (EXAMPLES 13-15) Ex.% GP% of s 0.02109 kg / cm2 0.04218 kg / cm2 CRET water of AUL of AUL 13 1.0 2.88 56.9 32.9 14 39.3 14 0.5 2.38 63.3 63.3 8.5 43.2 0.0 3.88 74.7 9.4 8.0 44.8% GP =% propylene glycol, or = surface tension - dmas / crn, AUL = absorbency under load g / g, CRET = centrifugal retention g / g. These examples illustrate the need to maintain the surface tension of the interlaced solution below about 55 dynes / crn.

EXAMPLES 16-18 The procedure for example 3 was substantially repeated, except for butanediol (butylene glycol) which was used instead of propylene glycol. The amount of butylene glycol was proactively reduced from 1.5% to 1.0% at 0.5%. Table 5 summarizes the results of these experiments. The quantity of the interbedded solution was maintained at 4.25% and the interleaving at 0.375%.

TABLE 5 (EXAMPLES 16-18) Ex.% GB% of 02109 kg / cm2 0.04218 kg / crn2 CRET water of AUL of AUL 16 1.5 2.38 51.4 32.9 26.7 36.5 17 1.0 2.88 55.1 33.3 26.3 37.8 18 0.5 3.38 60.8 32.8 18.4 38.5 % GB =% butylene glycol, or = surface tension -dines / crn, AUL = absorbency under load g / g, CRET = centrifugal retention g / g.

EXAMPLE 19 The procedure of Example 3 was substantially repeated, except that the crosslinker was diethylene glycol glycidyl ether (MU 224) and the weight percent of the crosslinked solution was 3.95% and the amount of the crosslinker was 0.33%. The surface tension of the interlaced solution was 49.8. The product had the following properties: 0.02109 Kg / cm2 of flul 34 0.04218 kg / cm2 of AUL 28.8 CRET 33.8 47 EXAMPLE 20 The product of Example 3 was substantially repeated, except that the propylene glycol was replaced by an equal amount of glycerin. The interlaced solution had a surface tension of 70.2 dynes per centimeter. The resulting polymer had the following properties: 0.04218 kg / cm2 of AUL 11.2 0.02109 Kg / cm2 of AUL 19.1 CRET 41.2 EXAMPLE 21 The products of Example 1 and Example 2 were analyzed to determine the powder content of each product. 20 g of the product were slowly added to a 600 ml vacuum flask by means of funnel which has a diameter of 150 inm and a height of 230 nm. The vacuum port of the flask was connected to a digital powder analyzer (Digital Dust Analyzer) Model P-5 manufactured by Sibata Scientific Technology Ltd., Tokyo, Japan, and distributed by MDA Instruments, Lmcolnshire, TL. The powder analyzer was calibrated for atmospheric dust levels normally before adding the test sample. The powder content of each sample was measured one minute after adding the solution to the flask. An average of three tests is recorded later for each test on dust counts per minute (CPM).

DUST CONTENT Example 1 13.3 ± 3.2 cprn Example 2 1.7 ± 0.6 cpm Additionally it has been discovered that a C3-C6 diol can be used to reduce the dust content of superabsorbent polymer compositions. Optionally, the diol can be applied as an aqueous solution. The amount of diol used depends, in part, on the equipment used to effect dispersion of the diol in the superabsorbent polymers and the amount of powder present in the compositions. Generally, the effective amount of diol will be between 0.1 to about 1% by weight; preferably from about 0.3 to about 0.6 percent by weight. An equal amount of water can be used to facilitate dispersion. However, it may be necessary to dry the polymer to add water to remove unwanted moisture.

EXAMPLE 22 This example illustrates a treatment for a superabsorbent polymer composition with an aqueous propylene glycol solution in an amount of about 1% glycol and about 1% water. 1750 parts of SANUIET water-absorbing resin "(Lot # 32204) was placed in a laboratory-sized Patterson-Kelley mixer.An aqueous organic solution, 17.5 parts of propylene glycol and 17.5 parts of DI water, was sprayed into the powder. super absorbent polymer and mixed uniformly The resulting mixture was heated for about 30 minutes at 130 ° C. The airborne powder content of the resulting superabsorbent polymer was determined by the digital indicator of powder (Digital Dust Indicator) model P-5, manufactured by Sibata Scientific Technology, Ltd. and is recorded in dust counts per minute. The absorption properties of the resulting superabsorbent polymer were analyzed by the absorbance or load (AUL) method at 0.02109 kg / cm2. The results comparatives are listed as follows: 2 ?! = * EXAMPLE 23 The procedure of example 2? is substantially repeated, except that the amount of propylene glycol is reduced to 0.4% based on the weight of the polymer and the water concentration was reduced to zero. A similar low powder content (4 cpm) is obtained in the treated polymer. The superabsorbent polymers of this invention are useful in the manufacture of moisture absorbing articles, such as disposable diapers, sanitary napkins, incontinence garments, bandages, and the like. The superabsorbent compositions of this invention are particularly in the manufacture of thin and ultra-thin disposable diapers which have excellent moisture absorbency, liquid distribution properties and reduced leakage. In the manufacture of absorbent articles or in the compositions of this invention, the superabsorbent composition may be blended with, added to, laminated to, or dispersed in a porous fiber matrix. Said matrices are made with hydrophilic fibers such as wood pulp or pellet, cotton linings, and synthetic fibers or a mixture of fibers and wood fluff. The fibers may be loose or bonded as in nonwoven fabrics. The synthetic fibers can be made of polyethylene, polypropylene, polyester, polyester copolymers and polyamides and the like. The synthetic fibers can be blown fibers under melt or fibers that have been treated to make them hydrophilic. Finally, the superabsorbent polymers of the invention may be incorporated in the absorbent article in a localized compartment or area of the absorbent structure. Absorbent articles, such as disposable diapers, are made of a liquid-impermeable backing material, a liquid-permeable material (Je facing the body side and a mixed fluid-absorbing body sandwiched between the backing material and the material). The liquid-impermeable backing material may be made of commercially available polyolefin film and the liquid permeable front material may be made of a commercially available nonwoven fabric material, such as a spunbonded fibrous web. or in the form of cord which is convenient and capable of passing urine The inventive articles of the invention may comprise from about 5% to about 90% by weight of the superabsorbent polymers of the invention In a typical absorbent article, the superabsorbent polymer of The invention may be dispersed in a fiber matrix in which the superabsorbent is present in a amount of about 30 to 70% by weight and the fiber matrix comprises 70 to 30% by weight of the article. In another form of absorbent article, the superabsorbent may be present in a containment structure in which the superabsorbent polymer is present in an amount of about 30 to 90% by weight. Also known are combinations of dispersed sorptorbent polymer and contained sorptive polymer. The superabsorbent polymers of this invention can be used in the manufacture of absorbent articles such as those described in US Patent Nos. 3,669,103; 3,670,731; 4,654,039; 4,699,823; 4,430,086; 4,973,325 4,892,598; 4,798,603; 4,500,315; 4,596,567; 4,938,756 4,637,590; 4,935,022; 4,673,402; 5,061,259; 5,147,343 5,149,335; and 5,156,902; the teachings of which are incorporated into the preeminent by reference.

Claims (26)

NOVELTY OF THE INVENTION CLAIMS

1. - A superabsorbent polymer that has a value

0. 04218 kg / cm2 of AUL of at least 25 g / g at a centrifugal retention value of at least 35 g / g where said super-absorbent polymer is the product of a process comprising dispersion to an aqueous solution of C3-Ce diol and an entangled compound having at least two functional reactive groups in a partially neutralized carboxyl or carboxylate group base interlaced polymer having a value of 0.02109 kg / cm2 of 15 g AUL / go menoe, and heating said dispersion to entangle said polymer wherein said aqueous solution has a surface tension that is not greater than about 55 dynes per cn.

2. A superabsorbent polymer according to claim 1, characterized in that said base polymer is a partially neutralized polyacrylic acid polymer.

3.- A polymer sup > Absorbent according to claim 1, further characterized in that said base polymer has a centrifugal retention value of at least 40 g / g.

4. A super-absorbent polymer according to claim 1, further characterized in that said base polymer is an L-acrylic acid copolymer and a water-soluble hydroxy group polymer.

5. A superabsorbent polymer according to claim 1, further characterized in that said C3-Ce diol is propylene glycol and the surface tension of said aqueous solution is not greater than about 50 dynes per cent.

6. A superabsorbent polymer according to claim 1, further characterized in that said entangled compound is selected from the group comprising diglycidyl ether compounds, adductions of polyamide-epichlorohydrin, adductions of polyamino epichlorohydrin and adductions of amino-polyfin-epichlorohydrin.

7. A superabsorbent polymer according to claim 1, further characterized in that said entangled compound is an adduct of a ino-polyrneno-epichlorohydrin wherein at least 50% of the reactive groups of said adduct are the acetydinium group .

8. A super-absorbent polymer according to claim 1, further characterized in that said interlaced compound is an adduct of arnino-p > olírnero-epiclorohi dri na where approximately 90% moles of the reactive groups of said adduct are the acetidinium group.

9. ~ A p > The super-absorbent oligogen according to claim 1, further characterized in that said entangled compound is diethylene glycolylglycidyl ether.

10. A process for preparing a superabsorbent polymer comprising dispersion to an aqueous solution of a C3-C6 diol and an interlaced compound having at least two functional reactive groups on the surface of a crosslinked polymer of a base. carboxyl or carboxylate, partially neutralized, having a value of 0.02109 kg / cm 2 of AUL of 15 g / g and heating the mixture to crosslink said polymer wherein said aqueous solution has a surface tension not greater than about 55 dynes per crn

11. A method according to claim 9, further characterized in that said polymer based is a partially neutralized polyacrylic acid.

12. A method according to claim 9,. further characterized in that said base polymer has a centrifugal retention value of at least 40 g / g.

13. A method according to claim 9, further characterized in that it is a superabsorbent polymer according to claim 8, wherein said base polymer is an acrylic acid copolymer and a water-soluble hydroxyl group polymer. .

14. A process according to claim 9, further characterized in that said diol of C3-Ce is propylene glycol and the superabsorbent tension of said aqueous solution is not greater than about 50 dynes porin.

15. A method according to claim 9, further characterized in that said interlaced compound is selected from the group comprising 5L compounds. of diglycidyl ether, adducts of polyamide-epichlorohydp a, adductions of polyamino epichlorohydrin and adductions of polynin-epichlorohydrin ainino.

16. A super-absorbent polymer according to claim 9, further characterized in that said interlaced compound is an amino-polyhydro-epichlorohydrin wherein at least 50% of the reactive groups of said adduct are the acetydinium group .

17. A superabsorbent polymer according to claim 9, further characterized in that said entangled compound is an amino-polymer-epichlorohydrin wherein approximately 90% of the reactive groups of said adduct are the acetydinium group.

18. An absorbent article comprising about 5 to about 90% by weight of a superabsorbent polymer composition in accordance with the claim 1, and about 10 to about 95% by weight of a hydrophilic fiber.

19. An absorbent article comprising about 30 to about 90% by weight of a superabsorbent polymer composition according to claim 1, and about 10 to about 70% by weight of a hydrophilic fiber.

20 - An absorbent article comprising about 30 to about 70% by weight of a polymer or superabsorbent composition according to claim R? 1, and about 30 to about 70% by weight of a hydrophilic fiber.

21. A method for reducing the dust content of a super absorbent polymer particle composition comprising contacting said particles with an aqueous solution of a C3-C6 diol in an interlaced compound.

22. A method according to claim 20, further characterized in that said aqueous solution has a surface tension that is not greater than about 55 dynes per cm.

23. A method according to claim 20, further characterized in that said aqueous solution has a surface tension that is not greater than about 50 dynes per cm.

24. A method for reducing the dust content of a superabsorbent polymer composition comprising mixing said composition with an effective amount of a diol of C3 to Ce.

25. A method according to claim 23, further characterized in that said diol is propylene glycol.

26. A method according to claim 23, further characterized in that said diol is an aqueous solution.