Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
  • A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
  • A61L15/22—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons containing macromolecular materials
  • A61L15/24—Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives thereof
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
  • A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
  • A61L15/22—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons containing macromolecular materials
  • A61L15/26—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives thereof
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
  • B01J20/22—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising organic material
  • B01J20/26—Synthetic macromolecular compounds
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F8/00—Chemical modification by after-treatment
  • C08F8/34—Introducing sulfur atoms or sulfur-containing groups
  • C08F8/36—Sulfonation; Sulfation
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F8/00—Chemical modification by after-treatment
  • C08F8/44—Preparation of metal salts or ammonium salts
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
  • C08L23/26—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers modified by chemical after-treatment
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
  • D01F6/00—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
  • D01F6/28—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds
  • D01F6/30—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds comprising olefins as the major constituent
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
  • D01F8/00—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof
  • D01F8/04—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof from synthetic polymers
  • D01F8/06—Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof from synthetic polymers with at least one polyolefin as constituent
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F2800/00—Copolymer characterised by the proportions of the comonomers expressed
  • C08F2800/10—Copolymer characterised by the proportions of the comonomers expressed as molar percentages
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F2810/00—Chemical modification of a polymer
  • C08F2810/50—Chemical modification of a polymer wherein the polymer is a copolymer and the modification is taking place only on one or more of the monomers present in minority

Definitions

• This present invention describes absorbent compositions comprising 5 sulfonated substantially random interpolymers.
• the sulfonated substantially random interpolymers can be used either alone or as blends with other polymers, and can be in either the sulfonic acid form, or as a neutralized or partially neutralized sulfonate salt.
• Another feature of the present invention is a process to prepare the sulfonated substantially random interpolymers, comprising the use of a hydrocarbon swelling
• the sulfonated substantially random interpolymers or blends therefrom can be used to prepare structures such as pellets, film, ribbon, sheet, strand or fiber, or closed and open cell foams, and fabricated articles therefrom.
• interpolymers by varying the relative amount of alpha olefin and vinyl or vinylidene aromatic monomer content provides a great deal of flexibility in tailoring their properties for a particular end use application.
• copending US Application No. 09/317,389 filed on May 24th 1999 and PCT Publication WO 99/64500 describes the use of substantially random interpolymers in formable membranes. Also,
• polystyrene and styrenic block copolymers are often sulfonated at the aromatic ring.
• US Patent Nos. 5468,574 and 5,679,482 disclose ion-conducting membranes prepared from polymers composed of sulfonated hydrogenated block copolymers of styrene and butadiene.
• the sulfonated aromatic rings be randomly dispersed throughout the polymer chains and, in order to precisely tailor the resulting product properties, that the sulfonation be done in a controlled fashion such that all degrees of sulfonation can be attained including surface sulfonation, bulk sulfonation or anything in between.
• ionomer applications These require both low sulfonation conversion, (that is ⁇ approximately lOpercent) and localized sulfonation resulting in ionic domains called clusters, which propagate physical crosslinks at low levels.
• PCT Publication WO 99/20691 discloses surface sulfonated substantially random interpolymers and articles therefrom as in the form of sheet or film, and that films and sheets made from such polymers can be used to "improve the barrier properties of articles to gases".
• the sulfonation of any particular phenyl group in such substantially random interpolymers has minimal directing effect on the sulfonation of other phenyl group in the interpolymer.
• the absorbent fibers of the present invention can be initially formed comprising the substantially random polymers which fibers can then be subsequently sulfonated to the required degree.
• the fibers can be directly fabricated from the sulfonated substantially random interpolymers.
• the use of the materials and processes of the present invention allows the design of bicomponent/biconstituent materials comprising the sulfonated substantially random interpolymers for performance and cost optimization.
• the present invention pertains to an absorbent polymer composition comprising
• A) one or more sulfonated substantially random interpolymers comprising repeating units derived from; a) ethylene and/or one or more alpha olefins; b) one or more sulfonated vinyl or vinylidene aromatic monomers; c) one or more vinyl or vinylidene aromatic monomers, or a combination of one or more vinyl or vinylidene aromatic monomers and one or more sterically hindered aliphatic or cycloaliphatic vinyl or vinylidene monomers; and optionally B) one or more polymers other than said sulfonated substantially random interpolymer.
• compositions include the preparation of absorbent foams, fibers films and membranes as well as the preparation of absorbent fabricated articles for personal hygiene. These include diapers, sanitary napkins, adult incontinence pads, and highly absorbent wipes, and dust pickups. All references herein to elements or metals belonging to a certain Group refer to the Periodic Table of the Elements published and copyrighted by CRC Press, Inc., 1989. Also any reference to the Group or Groups shall be to the Group or Groups as reflected in this Periodic Table of the Elements using the IUPAC system for numbering groups.
• any numerical values recited herein include all values from the lower value to the upper value in increments of one unit provided that there is a separation of at least 2 units between any lower value and any higher value.
• the amount of a component or a value of a process variable such as, for example, temperature, pressure, time is, for example, from 1 to 90, preferably from 20 to 80, more preferably from 30 to 70, it is intended that values such as 15 to 85, 22 to 68, 43 to 51, 30 to 32 etc. are expressly enumerated in this specification.
• one unit is considered to be 0.0001, 0.001, 0.01 or 0.1 as appropriate.
• hydrocarbyl as employed herein means any aliphatic, cycloaliphatic, aromatic, aryl substituted aliphatic, aryl substituted cycloaliphatic, aliphatic substituted aromatic, or aliphatic substituted cycloaliphatic groups.
• hydrocarbyloxy means a hydrocarbyl group having an oxygen linkage between it and the carbon atom to which it is attached.
• interpolymer is used herein to indicate a polymer wherein at least two different monomers are polymerized to make the interpolymer. This includes copolymers, terpolymers, etc.
• absorbent polymer composition is used herein to indicate a polymer or blend of polymers able to take up at least 5, preferably at least 50, more preferably at least 100 percent of its own weight when placed in water.
• superabsorbent polymer is used herein in the conventional sense in reference to polymeric materials that imbibe fluid and thereby form a swollen hydrogel. That is, a superabsorbent polymer is a hydrogel-forming polymeric gelling agent.
• the polymeric gelling agent comprises a substantially water- insoluble, partially neutralized, hydrogel-forming polymer material that is typically prepared from polymerizable, unsaturated, acid-containing monomers and often grafted onto other types of polymer moieties and then slightly crosslinked with agents such as, for example, triallyl amine. See, for example, U.S. Patent No. 5,061,259 and U.S. Patent No. 4,654,039, the disclosures of which are incorporated herein by reference, for additional description pertaining to superabsorbent polymers.
• Superabsorbent polymer is referenced herein by the acronym "SAP".
• absorbent fabricated article is used herein to indicate an article such as a foam, fiber, film, membrane, or any article prepared therefrom which in turn comprises the absorbent polymer compositions of the present invention. More specifically, the term refers to devices that are placed against or in proximity to the body of the wearer to absorb and contain the various exudates discharged from the body. These exudates include, but are not limited to urine, menses, vaginal discharge, sweat and feces.
• the devices include, but are not limited to absorbent articles for personal hygiene such as diapers, sanitary napkins and adult incontinence pads,
• substantially random in the substantially random interpolymer comprising polymer units derived from ethylene and one or more ⁇ -olefin monomers with one or more vinyl or vinylidene aromatic monomers and/or sterically hindered aliphatic or cycloaliphatic vinyl or vinylidene monomers
• the distribution of the monomers of said interpolymer can be described by the Bernoulli statistical model or by a first or second order Markovian statistical model, as described by J. C. Randall in POLYMER SEQUENCE DETERMINATION.
• substantially random inte ⁇ olymers do not contain more than 15 percent of the total amount of vinyl aromatic monomer in blocks of vinyl aromatic monomer of more than 3 units.
• the interpolymer is not characterized by a high degree of either isotacticity or syndiotacticity. This means that in the carbon "13 NMR spectrum of the substantially random interpolymer the peak areas corresponding to the main chain methylene and methine carbons representing either meso diad sequences or racemic diad sequences should not exceed 75 percent of the total peak area of the main chain methylene and methine carbons.
• degree of sulfonation or “percent conversion” are used interchangeably and as used herein refer to the percentage of the aromatic content of the aromatic groups in the unsulfonated substantially random interpolymer which are converted to sulfonated aromatic groups on sulfonation (on a scale of 0 to 100). It is calculated from the percent weight gain of the interpolymer on sulfonation using the following formula:
• homoofil refers to fiber which has a single polymer region or domain and does not have any other distinct polymer regions (as do bicomponent fibers), even though the polymer itself may have a plurality of phases or microphases.
• meltblown is used herein in the conventional sense to refer to fibers formed by extruding the molten elastic composition through a plurality of fine, usually circular, die capillaries as molten threads or filaments into converging high velocity gas streams (for example air) which function to attenuate the threads or filaments to reduced diameters. Thereafter, the filaments or threads are carried by the high velocity gas streams and deposited on a collecting surface to form a web of randomly dispersed fibers with average diameters generally smaller than 10 microns.
• high velocity gas streams for example air
• spunbond is used herein in the conventional sense to refer to fibers formed by extruding the molten elastic composition as filaments through a plurality of fine, usually circular, die capillaries of a spinneret with the diameter of the extruded filaments then being rapidly reduced and thereafter depositing the filaments onto a collecting surface to form a web of randomly dispersed spunbond fibers with average diameters generally between about 7 and about 30 microns.
• nonwoven as used herein and in the conventional sense means a web or fabric having a structure of individual fibers or threads which are randomly interlaid, but not in an identifiable manner as is the case for a knitted fabric.
• conjuggated refers to fibers which have been formed from at least two polymers extruded from separate extruders but meltblown or spun together to form one fiber.
• the interpolymers used in the present invention include the substantially random interpolymers, which are then sulfonated either prior to or after fabrication.
• the substantially random interpolymers are prepared by polymerizing i) ethylene and/or one or more ⁇ -olefin monomers and ii) one or more vinyl or vinylidene aromatic monomers and/or one or more sterically hindered aliphatic or cycloaliphatic vinyl or vinylidene monomers, and optionally iii) other polymerizable ethylenically unsaturated monomer(s).
• Suitable ⁇ -olefins include for example, ⁇ -olefins containing from 3 to 20, preferably from 3 to 12, more preferably from 3 to 8 carbon atoms.
• ethylene propylene, butene-1, 4-methyl-l-pentene, hexene-1 or octene-1 or ethylene in combination with one or more of propylene, butene-1, 4- methyl-1- ⁇ entene, hexene-1 or octene-1.
• ⁇ -olefins do not contain an aromatic moiety.
• Suitable vinyl or vinylidene aromatic monomers which can be employed to prepare the interpolymers, include, for example, those represented by the following formula:
• R i — C C(R2) 2
• R 1 is selected from the group of radicals consisting of hydrogen and alkyl radicals containing from 1 to 4 carbon atoms, preferably hydrogen or methyl
• each R 2 is independently selected from the group of radicals consisting of hydrogen and alkyl radicals containing from 1 to 4 carbon atoms, preferably hydrogen or methyl
• Ar is a phenyl group or a phenyl group substituted with from 1 to 5 substituents selected from the group consisting of halo, C 1- -alkyl, and C 1-4 -haloalkyl
• n has a value from zero to 4, preferably from zero to 2, most preferably zero.
• Exemplary vinyl or vinylidene aromatic monomers include styrene, vinyl toluene, ⁇ -methylstyrene, t-butyl styrene, chlorostyrene, including all isomers of these compounds,.
• Particularly suitable such monomers include styrene and lower alkyl- or halogen-substituted derivatives thereof.
• Preferred monomers include styrene, ⁇ -methyl styrene, the lower alkyl- ( - C ) or phenyl-ring substituted derivatives of styrene, such as for example, ortho-, meta-, and para-methylstyrene, the ring halogenated styrenes, para-vinyl toluene or mixtures thereof.
• a more preferred aromatic vinyl monomer is styrene.
• sterically hindered aliphatic or cycloaliphatic vinyl or vinylidene compounds it is meant addition polymerizable vinyl or vinylidene monomers corresponding to the formula:
• a 1 R 1 — C C(R 2 ) 2
• a 1 is a sterically bulky, aliphatic or cycloaliphatic substituent of up to 20 carbons
• R 1 is selected from the group of radicals consisting of hydrogen and alkyl radicals containing from 1 to 4 carbon atoms, preferably hydrogen or methyl
• each R 2 is independently selected from the group of radicals consisting of hydrogen and alkyl radicals containing from 1 to 4 carbon atoms, preferably hydrogen or methyl
• R 1 and A 1 together form a ring system.
• Preferred aliphatic or cycloaliphatic vinyl or vinylidene compounds are monomers in which one of the carbon atoms bearing ethylenic unsaturation is tertiary or quaternary substituted.
• substituents include cyclic aliphatic groups such as cyclohexyl, cyclohexenyl, cyclooctenyl, or ring alkyl or aryl substituted derivatives thereof, tert- butyl, norbornyl.
• Most preferred aliphatic or cycloaliphatic vinyl or vinylidene compounds are the various isomeric vinyl- ring substituted derivatives of cyclohexene and substituted cyclohexenes, and 5-ethylidene-2-norbornene. Especially suitable are 1-, 3-, and 4-vinylcyclohexene and 5-ethylidene-2-norbornene.
• Simple linear non- branched ⁇ -olefins including for example, ⁇ -olefins containing from 3 to 20 carbon atoms such as propylene, butene-1, 4-methyl-l-pentene, hexene-1 or octene-1 are not examples of sterically hindered aliphatic or cycloaliphatic vinyl or vinylidene compounds.
• ethylenically unsaturated monomer(s) include norbornene and Ci-to alkyl or C 6-10 aryl substituted norbornenes, with an exemplary interpolymer being ethylene/styrene/norbornene.
• the most preferred substantially random interpolymers are the ethylene/styrene, ethylene/propylene/styrene, ethylene/styrene/norbornene, and ethylene/propylene/styrene/norbornene interpolymers.
• the substantially random interpolymers include the pseudo-random interpolymers as described in EP-A-0,416,815 by James C. Stevens et al. and US
• the substantially random interpolymers can be prepared by polymerizing a mixture of polymerizable monomers in the presence of one or more metallocene or constrained geometry catalysts in combination with various cocatalysts. Preferred operating conditions for such polymerization reactions are pressures from atmospheric up to 3000 atmospheres and temperatures from -30°C to 200°C.
• Polymerizations and unreacted monomer removal at temperatures above the autopolymerization temperature of the respective monomers may result in formation of some amounts of homopolymer polymerization products resulting from free radical polymerization.
• substantially random ⁇ -olefin/vinyl aromatic interpolymers can also be prepared by the methods described in JP 07/278230 employing compounds shown by the general formula Cp l Rl
• Cp2 R2 where Cp 1 and Cp 2 are cyclopentadienyl groups, indenyl groups, fluorenyl groups, or substituents of these, independently of each other; R 1 and R 2 are hydrogen atoms, halogen atoms, hydrocarbon groups with carbon numbers of 1-12, alkoxyl groups, or aryloxyl groups, independently of each other; M is a group IV metal, preferably Zr or Hf, most preferably Zr; and R 3 is an alkylene group or silanediyl group used to crosslink Cp 1 and Cp 2 .
• the substantially random ⁇ -olefin/vinyl aromatic interpolymers can also be prepared by the methods described by John G. Bradfute et al. (W. R. Grace & Co.) in WO 95/32095; by R. B. Pannell (Exxon Chemical Patents, Inc.) in WO 94/00500; and in Plastics Technology, p. 25 (September 1992).
• substantially random interpolymers which comprise at least one ⁇ -olefin/vinyl aromatic/vinyl aromatic/ ⁇ -olefin tetrad disclosed in U. S. Application No. 08/708,869 filed September 4, 1996 and WO 98/09999 both by Francis J. Timmers et al.
• These interpolymers contain additional signals in their carbon- 13 NMR spectra with intensities greater than three times the peak to peak noise. These signals appear in the chemical shift range 43.70 - 44.25 ppm and 38.0 - 38.5 ppm. Specifically, major peaks are observed at 44.1, 43.9, and 38.2 ppm.
• a proton test NMR experiment indicates that the signals in the chemical shift region 43.70 - 44.25 ppm are methine carbons and the signals in the region 38.0 - 38.5 ppm are methylene carbons.
• ⁇ -olefin/vinyl aromatic monomer interpolymers such as propylene/styrene and butene/styrene are described in United States patent number 5,244,996, issued to Mitsui Petrochemical Industries Ltd or United States patent number 5,652,315 also issued to Mitsui Petrochemical Industries Ltd or as disclosed in DE 197 11 339 Al and U.S. Patent No. 5,883,213 to Denki Kagaku Kogyo KK. All the above methods disclosed for preparing the interpolymer component are incorporated herein by reference. Also, the random copolymers of ethylene and styrene as disclosed in Polymer Preprints Vol 39, No. 1, March 1998 by Toru Aria et al.
• an amount of atactic vinyl aromatic homopolymer may be formed due to homopolymerization of the vinyl aromatic monomer at elevated temperatures.
• the presence of vinyl aromatic homopolymer is in general not detrimental for the purposes of the present invention and can be tolerated.
• the vinyl aromatic homopolymer may be separated from the interpolymer, if desired, by extraction techniques such as selective precipitation from solution with a non solvent for either the interpolymer or the vinyl aromatic homopolymer.
• the substantially random interpolymers can be sulfonated by any suitable means known in the art for sulfonating aromatic ring compounds including using so called “wet” (sulfuric acid, oleum, chlorosulphonic acid, SO 3 complexes) or gaseous (air sulfonation, SO3 vapor phase sulfonation) reagents.
• wet sulfuric acid, oleum, chlorosulphonic acid, SO 3 complexes
• gaseous air sulfonation, SO3 vapor phase sulfonation
• a preferred method involves contacting the substantially random interpolymer with a fluid phase of sulfur trioxide, present as minor composition (less than 50 percent by weight) in another carrier gas such as nitrogen or air at a temperature of from 20°C to 200°C, preferably from 50°C to 150°C, more preferably from 80°C to 150°C.
• a C ⁇ -C 2 o, preferably C ⁇ -C 10 , more preferably C ⁇ -C 6 hydrocarbon swelling agent including but not exclusively ethane, propane, butane, pentane, hexane, and cyclohexane
• the interpolymer can be exposed to the swelling agent prior to sulfonation.
• the substantially random interpolymer can also be sulfonated by contacting with a liquid phase of oleum (5-60 percent sulfur trioxide dissolved in sulfuric acid), at a temperature of from -20°C to 100°C, preferably from 0°C to 80°C, more preferably from 0°C to 50°C.
• the polymer can be exposed to a Cj . -C 2 o, preferably - o, more preferably Ci-C 6 hydrocarbon swelling agent (including, but not exclusively, pentane, hexane, and cyclohexane) either prior to or concurrently with sulfonation.
• the substantially random interpolymer is sulfonated by contacting with a sulfonating complex comprising the reaction product of 2 to 4 moles of sulfur trioxide and 1 mole of a lower trialkyl phosphate or phosphite at a temperature of from 25°C to 100°C, preferably from 50°C to 83°C, more preferably from 75°C to 83°C followed by recovering the resultant sulfonated polymer.
• Sulfur trioxide can also be supplied in the form of chlorosulfonic acid or fuming sulfuric acid.
• Particularly suitable trialkyl phosphates include trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, trimethyl phosphite, triethyl phosphite, tripropyl phosphite, tributyl phosphate, hydrogen phosphate, diethyl hydrogen phosphate, dimethyl hydrogen phosphite, diethyl hydrogen phosphite, methyl dihydrogen phosphate, ethyl dihydrogen phosphate, methyl dihydrogen phosphite, ethyl dihydrogen phosphite, any combination thereof.
• Another method of sulfonation is that described by H. S. Makowski, R. D.
• a mixed anhydride is prepared by mixing sulfuric acid with acetic anhydride at a temperature of from -70°C to 130°C (preferably between -20 to 20 °C) followed by adding this mixture to a solution of the interpolymer in a chlorinated solvent such as, for example dichloroethane, methylene chloride, chloroform, tetrachloroethane, trichloroethane or combinations thereof at a temperature of from -20 °C to 100°C.
• a chlorinated solvent such as, for example dichloroethane, methylene chloride, chloroform, tetrachloroethane, trichloroethane or combinations thereof at a temperature of from -20 °C to 100°C.
• the salts of the sulfonated interpolymers can be prepared by reacting with a neutralizing agent or base (ammonia, alkylamines, ammonium hydroxide, sodium hydroxide, etc.) in a solvent or as a gas phase at temperatures of from -20 °C to about 100°C, preferably from 40°C to 100°C, more preferably from 60°C to 80°C for a period of time to convert essentially all of the SO 3 H groups to the neutralized salt, - SO 3 Me (where Me is the counterion). This time is usually from about 0.01 to 240, preferably from 1 to 60, more preferably from 5 to 30 minutes. Me can include a group 1, 2, 7, 11 or 12 metals of the Periodic Table of Elements.
• the amount of the neutralizing agent employed is that which is sufficient to convert substantially all of the sulfonate groups to the neutralized salt, usually from 1 to 1.5, preferably from 1 to 1.1, more preferably about 1 mole of the neutralizing agent per mole of sulfonate group present in the interpolymer.
• the amount of solvent employed is that amount sufficient to create a substantially homogeneous mixture, which can range from 5 to 95, preferably from 10 to 80, more preferably from 15 to 75 percent by weight based on the combined weight of the mixture.
• the sulfonated substantially random interpolymers comprise from 35 to 98.5 mol percent of polymer units derived from ethylene and/or said ⁇ -olefin which comprises at least one of propylene, 4-methyl-l-pentene, butene-1, hexene-1 or octene- 1 ; and from 1.5 to 65 mol percent of polymer units derived from one or more sulfonated vinyl aromatic monomers which are mono substituted with either a sulfonic acid group or a sulfonic acid salt represented by the following formula;
• R 1 — C C(R 2 ) 2 wherein R is selected from the group of radicals consisting of hydrogen and alkyl radicals containing from 1 to 4 carbon atoms, each R 2 is independently selected from the group of radicals consisting of hydrogen and alkyl radicals containing from 1 to 4 carbon atoms, Ar is a phenyl group or a phenyl group substituted with from 1 to 5 substituents selected from the group consisting of halo, C 1-4 -alkyl, and C 1- -haloalkyl; and n has a value from zero to 4, and X is hydrogen, a group 1, 2, 7, 11 or 12 metal ion, an ammonium salt NR' 4 + where R' is hydrogen or a C3-C20 alkyl or a combination thereof;
• suitable metal salts which can be employed herein include the salts formed from group 1, 2, 7, 11 or 12 metals as well as the ammonium (NH 4 + ) salts.
• Particularly suitable metals of group 1, 2, 7, 11, or 12 include Na, K, Li, Co, Cu, Mg, Ca, Mn, or Zn. Also suitable are the hydroxides of such metals. Particularly suitable salts and hydroxides include the hydroxides, acetates, hexanoates, and oxides of Na, Li, K, Ca, Mg, Cu, Co, Zn Al, NH 4 +, and any combination thereof. Also suitable are the hydrates of the aforementioned salts.
• the sulfonated substantially random interpolymers would thus also comprise polymer units derived from the starting substantially random interpolymer namely ethylene and/or one or more ⁇ -olefin monomers and ii) one or more vinyl or vinylidene aromatic monomers and/or one or more sterically hindered aliphatic or cycloaliphatic vinyl or vinylidene monomers, and optionally iii) other polymerizable ethylenically unsaturated monomer(s). Additional Blend Component(s).
• the polymers used to prepare the absorbent compositions of the present invention can also comprise one or more polymers other than the sulfonated substantially random interpolymer.
• These additional polymers can comprise homogenous ⁇ -olefin homopolymer or interpolymers comprising polypropylene, propylene/C 4 -C 20 ⁇ - olefin copolymers, polyethylene, and ethylene/C 3 -C 20 ⁇ - olefin copolymers
• the interpolymers can be either heterogeneous ethylene/ ⁇ -olefin interpolymers , preferably a heterogeneous ethylene/ C 3 -C 8 ⁇ -olefin interpolymer, most preferabl a heterogeneous ethylene/ octene-1 inteipolymer or homogeneous ethylene/ ⁇ - olefin interpolymers, including the substantially linear ethylene/ ⁇ -olefin interpolymers, preferably a substantially linear ethylene/ ⁇ -ole
• Such polymers can comprise nonionic polymers like polyacrylamide, polyethylene oxide, polyvinyl alcohol; anoionic polymers and their neutralized salts including polyacrylic acid, graft copolymers including starch-g- poly acrylic acid, poly (vinyl alcohol-g-poly acrylic acid), hydrolyzed starch-g- poly (acrylonitrile), carboxymethylcellulose, alginic acid; cationic polymers including poly(diallyldimethylammonium chloride, polyvinylpyridine, cationic starches, and hydroyzed chitin. These materials can be optionally crosslinked to prevent dissolution into water.
• Fillers Also included as a potential component of the polymer compositions used in the present invention are various organic and inorganic fillers, the identity of which depends upon the type of application for which the composition is to be utilized.
• the fillers can also be included in the sulfonated substantially random interpolymer, component, the other polymer component and/or the overall blend compositions employed in the present invention.
• fillers include organic and inorganic fibers such as those made from asbestos, boron, graphite, ceramic, glass, metals (such as stainless steel) or polymers (such as aramid fibers) talc, carbon black, carbon fibers, calcium carbonate, alumina trihydrate, glass fibers, marble dust, cement dust, clay, feldspar, silica or glass, fumed silica, alumina, magnesium oxide, magnesium hydroxide, antimony oxide, zinc oxide, barium sulfate, aluminum silicate, magnesium aluminum silicate, calcium silicate, titanium dioxide, titanates, aluminum nitride, B 2 O 3 , nickel powder or chalk.
• organic and inorganic fibers such as those made from asbestos, boron, graphite, ceramic, glass, metals (such as stainless steel) or polymers (such as aramid fibers) talc, carbon black, carbon fibers, calcium carbonate, alumina trihydrate, glass fibers, marble dust, cement dust, clay, feldspar, silica or glass
• organic or inorganic, fiber or mineral, fillers include carbonates such as barium, calcium or magnesium carbonate; fluorides such as calcium or sodium aluminum fluoride; hydroxides such as aluminum hydroxide; metals such as aluminum, bronze, lead or zinc; oxides such as aluminum, antimony, magnesium or zinc oxide, or silicon or titanium dioxide; silicates such as asbestos, mica, clay (kaolin or calcined kaolin), feldspar, glass (ground or flaked glass or hollow glass spheres or microspheres or beads, whiskers or filaments), nepheline, perlite, pyrophyllite, talc or wollastonite; sulfates such as barium or calcium sulfate; metal sulfides; cellulose, in forms such as wood or shell flour; calcium terephthalate; and liquid crystals. Also included are the various classes of fillers that act as anti-microbial agents. Mixtures of more than one such filler may be used as well. Other Additives
• Additives such as antioxidants (for example, hindered phenols such as, for example, J ganoxTM 1010), phosphites (for example, IrgafosTM 168) both trademarks of, and commercially available from, Ciba Geigy Corporation), U. V. stabilizers, cling additives (for example, polyisobutylene), antiblock additives, colorants, pigments, are optionally also included in in the sulfonated substantially random interpolymer, component, the other polymer component and/or the overall blend compositions employed in the present invention, to the extent that they do not interfere with the enhanced properties discovered by Applicants.
• antioxidants for example, hindered phenols such as, for example, J ganoxTM 1010
• phosphites for example, IrgafosTM 168) both trademarks of, and commercially available from, Ciba Geigy Corporation
• U. V. stabilizers for example, polyisobutylene
• antiblock additives for example,
• Processing aids which are also referred to herein as plasticizers, can also be included in the sulfonated substantially random interpolymer, component, the other polymer component and/or the overall blend compositions employed in the present invention.
• phthalates such as dioctyl phthalate and diisobutyl phthalate
• natural oils such as lanolin, and paraffin
• naphthenic and aromatic oils obtained from petroleum refining
• liquid resins from rosin or petroleum feedstocks rosin or petroleum feedstocks.
• Exemplary classes of oils useful as processing aids include white mineral oil (such as KaydolTM oil (available from and a registered trademark of Witco), and ShellflexTM 371 naphthenic oil (available from and a registered trademark of Shell Oil Company).
• Tackifiers can also be included in the sulfonated substantially random interpolymer, component, the other polymer component and/or the overall blend compositions employed in the present invention, to alter the processing performance of a polymer and thus extend the available application temperature window of the application.
• a suitable tackifier may be selected on the basis of the criteria outlined by Hercules in J. Simons, Adhesives Age, "The HMDA Concept: A New Method for Selection of Resins", November 1996.
• Tackifying resins can be obtained by the polymerization of petroleum and terpene feedstreams and from the derivatization of wood, gum, and tall oil rosin.
• tackifiers include wood rosin, tall oil and tall oil derivatives, and cyclopentadiene derivatives, such as are described in United Kingdom patent application GB 2,032,439A.
• Other classes of tackifiers include aliphatic C5 resins, polyterpene resins, hydrogenated resins, mixed aliphatic- aromatic resins, rosin esters, natural and synthetic terpenes, terpene-phenolics, and hydrogenated rosin esters.
• the additives are advantageously employed in functionally equivalent amounts known to those skilled in the art.
• the amount of antioxidant employed is that amount which prevents the polymer or polymer blend from undergoing oxidation at the temperatures and environment employed during storage and ultimate use of the polymers.
• Such amount of antioxidants is usually in the range of from 0.01 to 10, preferably from 0.05 to 5, more preferably from 0.1 to 2 percent by weight based upon the weight of the polymer or polymer blend.
• the amounts of any of the other enumerated additives are the functionally equivalent amounts such as the amount to render the polymer or polymer blend antiblocking, to produce the desired amount of filler loading to produce the desired result, to provide the desired color from the colorant or pigment.
• Such additives are advantageously employed in the range of from 0.05 to 50, preferably from 0.1 to 35, more preferably from 0.2 to 20 percent by weight based upon the weight of the polymer or polymer blend.
• Fillers can be advantageously employed in amounts up to about 90 percent by weight based on the weight of the polymer or polymer blend.
• the sulfonated substantially random interpolymers and blends therefrom of the present invention can be available in a wide range of structures including but not limited to, fibers, films, sheet, and foams, and fabricated articles therefrom Preparation of Fibers Comprising the Sulfonated Substantially Random Interpolymers
• the sulfonated substantially random interpolymers are used to prepare absorbent fibers.
• the fibers can be prepared from the sulfonated substantially random interpolymers using the methods described herein.
• the fibers can be prepared from the substantially random interpolymers and then the resulting fiber can then be sulfonated either after or during the fiber manufacturing process, using the sulfonation processes described herein. In such a post fiber sulfonation process, the nature and incorporation of the previously described swelling and sulfonation agents and reaction times can then be tailored to the particular fiber preparation.
• the main advantages of the sulfonated substantially random interpolymers versus other polymers such as sulfonated polystyrene for use in fibers are the improved physical properties such as flexibility resulting from the occurrence of aromatic and ethylene and/or alpha olefin functionality in the polymer and their relative distributions. Polystyrene and sulfonated polystyrene by itself will be very brittle.
• the olefinic groups of the sulfonated substantially random interpolymer component provide improved compatibility with a polyolefin core fiber in bicomponent structures.
• the ethylene groups can provide some degree of hydrophobicity to the fiber, keeping it from dissolving even when all the aromatic rings are sulfonated.
• the absorbent fibers of the present invention can be prepared using techniques well known in the art including for example, dry lay, wet lay, carding, spin bonding, garnetting, and air laying processes. (See, for example U.S. Patents 5,108,827, 5,487,943, 4,176,108 and 4,814,226).
• Nonwoven fabrics and articles can be prepared using binding techniques including, for example, hot roll, hot press, lamination, hot air bonding, calendar, spray, dip and roll transfer processes. (See, for example, U.S. Patents 5,824,610, 5,593,768, 5,169,580 and 5,244,695).
• the diameter can be widely varied. Fiber diameter can be measured and reported in a variety of fashions. Generally, fiber diameter is measured in denier per filament. Denier is a textile term that is defined as the grams of the fiber per 9000 meters of that fiber's length. Monofilament generally refers to an extruded strand having a denier per filament greater than 15, usually greater than 30. Fine denier fiber generally refers to fiber having a denier of about 15 or less. Microdenier (aka microfiber) generally refers to fiber having a diameter not greater than about 100 micrometers.
• the fiber denier can be adjusted to suit the capabilities of the finished article and as such, would preferably be: from 0.5 to 30 denier/filament for melt blown; from 1 to 30 denier/filament for spunbond; and from 1 to 20,000 denier/filament for continuous wound filament. Nonetheless, preferably, the nominal denier is greater than 37, more preferably greater than or equal to 55 and most preferably greater than or equal to 65. These preferences are due to the fact that typically durable apparel employ fibers with deniers greater than or equal to about 40.
• Finishing operations can optionally be performed on the fibers of the present invention.
• the fibers can be texturized by mechanically crimping or forming such as described in Textile Fibers, Dyes, Finishes, and Processes: A Concise Guide, by Howard L. Needles, Noyes Publications, 1986, pp. 17-20.
• interpolymer compositions used to make the fibers of the present invention or the fibers themselves may also be modified by various cross-linking processes using curing methods at any stage of the fiber preparation including, but not limited to, before during, and after drawing at either elevated or ambient temperatures.
• cross-linking processes include, but are not limited to, peroxide-, silane-, sulfur-, radiation-, or azide-based cure systems.
• Dual cure systems which use a combination of heat, moisture cure, and radiation steps, may be effectively employed. Dual cure systems are disclosed and claimed in U. S. Patent Application Serial No. 536,022, filed on September 29, 1995, in the names of K. L. Walton and S. V. Karande, incorporated herein by reference. For instance, it may be desirable to employ peroxide crosslinking agents in conjunction with silane crosslinking agents, peroxide crosslinking agents in conjunction with radiation, sulfur- containing crosslinking agents in conjunction with silane crosslinking agents, etc.
• the polymer compositions may also be modified by various cross-linking processes including, but not limited to the incorporation of a diene component as a termonomer in its preparation and subsequent cross linking by the aforementioned methods and further methods including vulcanization via the vinyl group using sulfur for example as the cross linking agent.
• the fibers of the present invention may be surface functionalized by methods including, but not limited to, chlorination using chemical treatments for permanent surfaces or incorporating a temporary coating using the various well known spin finishing processes.
• the fibers comprising the sulfonated substantially random interpolymers can be essentially in the form of any fibers previously known in the art. This includes the homofil fibers including staple fibers, spunbond fibers or melt blown fibers (using, for example, systems as disclosed in USP 4,340,563 (Appel et al.), USP 4,663,220
• Staple fibers can be melt spun (that is, they can be extruded into the final fiber diameter directly without additional drawing), or they can be melt spun into a higher diameter and subsequently hot or cold drawn to the desired diameter using conventional fiber drawing techniques.
• the shape of the fiber is not limited.
• typical fiber has a circular cross-sectional shape, but sometimes fibers have different shapes, such as a trilobal shape, or a flat (that is, "ribbon” like) shape.
• the absorbent fibers disclosed herein, are not limited by the shape of the fiber.
• the fibers comprising the sulfonated substantially random interpolymers can also be used as bonding fibers, especially where the inventive fibers have a lower melting point than the surrounding matrix fibers.
• the bonding fiber is typically blended with other matrix fibers and the entire structure is subjected to heat, where the bonding fiber melts and bonds the surrounding matrix fiber.
• Typical matrix fibers which benefit from use of the inventive fibers disclosed herein include, but are not limited to, poly(ethylene terephthalate) fibers, cotton fibers, nylon fibers, polypropylene fibers, heterogeneously branched polyethylene fibers, homogeneously branched ethylene polymer fibers, linear polyethylene homopolymer fibers and combinations thereof.
• the diameter of the matrix fiber can vary depending upon the end use application.
• These fibers of the present invention can comprise more than one polymer, including wettable binder fibers (U.S. Patent 5,894,000); hydrophilic fibers, superabsorbent polymer fibers (U.S. Patents 5,593,399 and 5,698,480); and the fibers listed in U.S. Patent 4,176,108. Mixtures of fibers can also be employed. Examples of common materials used in the manufacture of fibers available for mixing with the fibers of the present invention include natural and synthetic materials such as, for example, polyethylene terephthalate, polyethylene, polypropylene, polyurethane, nylon, rayon, and cotton and other cellulosic materials.
• the absorbent fibers comprising the sulfonated substantially random interpolymers are conjugated or bicomponent or multi- component fibers (as disclosed in U.S. Patent Nos. 5,843,063; 5,169,580; 4,634,739; 5,921,973; 4,483,976; and 5,403,444).
• the polymer components are usually different from each other, although conjugated fibers may be mono-component fibers.
• the polymers are arranged in substantially constantly positioned distinct zones across the cross-section of the conjugated fibers and extend continuously along the length of the conjugated fibers.
• the configuration of the conjugated fibers of the present invention can be, for example, a sheath/core arrangement (wherein one polymer is surrounded by another), a side by side arrangement, a pie arrangement or an "islands-in-the sea” arrangement.
• Conjugated fibers are described in U.S Patent No. 5,108,820 to Kaneko et al; U.S. Patent No. 5,336,552 to Strack et al.; and U.S. Patent No. 5,382,400 to Pike et al., the disclosures of all of which are incorporated herein by reference.
• the fibers comprising the sulfonated substantially random interpolymers of the present invention can be in a conjugated configuration, for example, as a core or sheath, or both.
• Different sulfonated substantially random interpolymers can also be used independently as the sheath and the core in the same fiber, especially where the sheath component has a lower melting point than the core component.
• Nonwoven fabrics can be made variously, including spunlaced (or hydrodynamically entangled) fabrics as disclosed in USP 3,485,706 (Evans) and USP 4,939,016 (Radwanski et al.), the disclosures of which are incorporated herein by reference; by carding and thermally bonding staple fibers; by spunbonding continuous fibers in one continuous operation; or by melt blowing fibers into fabric and subsequently calandering or thermally bonding the resultant web.
• spunlaced (or hydrodynamically entangled) fabrics as disclosed in USP 3,485,706 (Evans) and USP 4,939,016 (Radwanski et al.), the disclosures of which are incorporated herein by reference; by carding and thermally bonding staple fibers; by spunbonding continuous fibers in one continuous operation; or by melt blowing fibers into fabric and subsequently calandering or thermally bonding the resultant web.
• nonwoven fabrics of the invention may be used in filtration applications, medical applications, clean room applications, garments, barrier products, sterilization wraps, interlinings, cushioning, CSR wrap, stretchable absorbent materials, and wipes.
• the absorbent articles of the present invention can be utilized in disposable products which are capable of absorbing significant quantities of body fluids, such as urine and water in body wastes.
• Such articles may be prepared in the form of sanitary napkins and other feminine hygiene products, disposable diapers, adult incontinence briefs, adult incontinence pads.
• the sulfonated substantially random interpolymer fibers are used in the construction of diapers, as part of the distribution, acquisition and/or surge layers and in the core.
• Especially preferred absorbent articles of this invention are disposable diapers. Articles in the form of disposable diapers are fully described in Duncan and Baker, U.S. Patent No. Re. 26,151, Issued Jan. 31, 1967; Duncan, U.S. Pat. No. 3,592,194, Issued Jul. 13, 1971; Duncan and Gellert, U.S. Pat. No. 3,489,148, Issued Jan. 13, 1970; and Buell, U.S. Pat. No. 3,860,003, Issued Jan. 14, 1975; which patents are incorporated herein by reference.
• the absorbent fibers of the present invention may be used as the sole superabsorbent core component or may be used in addition to the aforementioned core components of the prior art to facilitate liquid transport and alleviate the problem of gell blocking.
• Nonwoven products prepared with the absorbent fibers of the invention may also be useful in specialty applications such as the preparation of hygiene articles having patterned component distribution (see, for example, U.S. Patents 5,843,063, 5,593,399 and 5,941,862) and flushable diapers (see, for example, U.S. Patent 5,770,528).
• Woven fabrics can also be made which comprise the absorbent fibers of the present invention.
• the various woven fabric-manufacturing techniques are well known to those skilled in the art and the disclosure is not limited to any particular method.
• Woven fabrics are typically stronger and more heat resistant and are thus used typically in durable, non-disposable applications as for example in the woven blends with polyester and polyester cotton blends.
• the woven fabrics comprising the absorbent fibers of the present invention can be used in applications including but not limited to, upholstery, athletic apparel, carpet, fabrics, bandages.
• the fibers of the present invention can be included in the woven fabrics of the prior art (for example as staple fibers in existing fabrics) to promote absorbency.
• novel absorbent fibers described herein also can be used in a spunlaced (or hydrodynamically entangled) process to make novel structures.
• USP 4,801,482 (Goggans), the disclosure of which is incorporated herein by reference, discloses a sheet which can now be made with the novel fibers/fabric described herein.
• Composites that utilize very high molecular weight linear polyethylene or copolymer polyethylene also benefit from the novel fibers disclosed herein.
• the novel fibers that have a low melting point, such that in a blend of the novel fibers and very high molecular weight polyethylene fibers (as described in USP 4,584,347 by Harpell et al., the disclosure of which is incorporated herein by reference), the lower melting fibers bond the high molecular weight polyethylene fibers without melting the high molecular weight fibers, thus preserving the high strength and integrity of the high molecular weight fiber.
• Absorbent and superabsorbent foams have attracted considerable attention as candidates for replacing multiple components of an absorbent core. They hold the potential of offering some of the same advantages sought for film or fiber forms; performing the absorbent functions of multiple components of a conventional diaper, not migrating in the product, and not creating dust.
• superabsorbent polymer foams have been described in the patent literature. One approach seeks to embed conventional superabsorbent granules in non-superabsorbent foam.
• a second option is to utilize capillary suction forces, instead of or in addition to osmotic pressure, to create an absorbent material.
• Paper towels, sponges, and cellulose fluffs are examples of capillary absorbers.
• HIPEs high internal phase-ratio emulsions
• An important aspect of these foams is that they are inherently lipophilic, requiring a post-treatment in order to absorb aqueous solutions.
• the sulfonated substantially random interpolymers are used to prepare absorbent foams.
• the foams can be prepared from the sulfonated substantially random interpolymers using the methods described herein.
• the foams can be prepared from the substantially random interpolymers and then the resulting foams can then be sulfonated either after or during the foam manufacturing process, using the sulfonation processes described herein. In such a post foam sulfonation process, the nature and incorporation of the previously described swelling and sulfonation agents and reaction times can then be tailored to the particular foam preparation.
• Foam forming steps of the process are within the skill in the art. For instance as exemplified by the excellent teachings to processes for making ethylenic polymer foam structures and processing them in C. P. Park. "Polyolefin Foam", Chapter 9, Handbook of Polymer Foams and Technology, edited by D. Klempner and K. C. Frisch, Hanser Publishers, Kunststoff, Vienna, New York, Barcelona (1991), which is incorporated here in by reference.
• the absorbent foam structures of the present invention are optionally made by a conventional extrusion foaming process.
• the structure is advantageously prepared by heating the sulfonated substantially random interpolymer or blend to form a plasticized or melt polymer material, incorporating therein a blowing agent to form a foamable gel, and extruding the gel through a die to form the foam product.
• a blowing agent Prior to mixing with the blowing agent, the sulfonated substantially random interpolymer is heated to a temperature at or above its glass transition temperature or melting point.
• the blowing agent is optionally incorporated or mixed into the melt polymer material by any means known in the art such as with an extruder, mixer, blender, or the like.
• the blowing agent is mixed with the melt polymer material at an elevated pressure sufficient to prevent substantial expansion of the melt polymer material and to advantageously disperse the blowing agent homogeneously therein.
• a nucleator is optionally blended in the melt or dry blended with the sulfonated substantially random interpolymer prior to plasticizing or melting.
• the foamable gel is typically cooled to a lower temperature to optimize physical characteristics of the foam structure.
• the gel is then extruded or conveyed through a die of desired shape to a zone of reduced or lower pressure to form the foam structure.
• the zone of lower pressure is at a pressure lower than that in which the foamable gel is maintained prior to extrusion through the die.
• the lower pressure is optionally superatmospheric or subatmospheric (vacuum) but is preferably at an atmospheric level.
• the resulting absorbent foam structure is optionally formed in a coalesced strand form by extrusion of the polymer material through a multi-orifice die.
• the orifices are arranged so that contact between adjacent streams of the molten extrudate occurs during the foaming process and the contacting surfaces adhere to one another with sufficient adhesion to result in a unitary foam structure.
• the streams of molten extrudate exiting the die take the form of strands or profiles, which desirably foam, coalesce, and adhere to one another to form a unitary structure.
• the coalesced individual strands or profiles should remain adhered in a unitary structure to prevent strand delamination under stresses encountered in preparing, shaping, and using the foam.
• styrene monomer is optionally impregnated into the suspended pellets prior to their impregnation with blowing agent to form a graft interpolymer with the sulfonated substantially random interpolymer.
• blowing agent blowing agent
• Blowing agents useful in making the absorbent foam structures of the present invention include inorganic agents, organic blowing agents and chemical blowing agents. Suitable inorganic blowing agents include carbon dioxide, nitrogen, argon, water, air, nitrogen, and helium.
• Organic blowing agents include aliphatic hydrocarbons having 1-6 carbon atoms, aliphatic alcohols having 1-3 carbon atoms, and fully and partially halogenated aliphatic hydrocarbons having 1-4 carbon atoms.
• Aliphatic hydrocarbons include methane, ethane, propane, n-butane, isobutane, n-pentane, isopentane, neopentane,.
• Aliphatic alcohols include methanol, ethanol, n-propanol, and isopropanol.
• Fully and partially halogenated aliphatic hydrocarbons include fluorocarbons, chlorocarbons, and chlorofluorocarbons.
• fluorocarbons include methyl fluoride, perfluoromethane, ethyl fluoride, 1,1-difluoroethane (HFC- 152a), 1,1,1-trifluoroethane (HFC-143a), 1,1,1-2-tetrafluoro-ethane (HFC-134a), pentafluoroethane, difluoromethane, perfluoroethane, 2,2-difluoropropane, 1,1,1- trifluoropropane, perfluoropropane, dichloropropane, difluoropropane, perfluorobutane, perfluorocyclobutane.
• Partially halogenated chlorocarbons and chlorofluorocarbons for use in this invention include methyl chloride, methylene chloride, ethyl chloride, 1,1,1- trichloroethane, 1,1-dichloro-l fluoroethane (HCFC-141b), 1-chloro 1,1-difluoroethane (HCFC-142b), l-dichloro-2,2,2-trifluoroethane (HCFC-123) and 1-chloro- 1,2,2,2- tetrafluoroethane (HCFC-124).
• Fully halogenated chlorofluorocarbons include trichloromonofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12), trichlorotrifluoroethane (CFC-113), 1,1,1-trifluoroethane, pentafluoroethane, dichlorotetrafluoroethane (CFC-114), chloroheptafluoropropane, and dichlorohexafluoropropane.
• CFC-11 trichloromonofluoromethane
• CFC-12 dichlorodifluoromethane
• CFC-113 trichlorotrifluoroethane
• 1,1,1-trifluoroethane pentafluoroethane
• pentafluoroethane pentafluoroethane
• dichlorotetrafluoroethane CFC-114
• chloroheptafluoropropane dichlor
• Chemical blowing agents include azodicarbonamide, azodiisobutyro-nitrile, barium azodicarboxylate, N,N'-dimethyl-N,N'- dinitrosoterephthalamide, and benzenesulfonhydrazide, 4,4-oxybenzene sulfonyl semicarbazide, and p-toluene sulfonyl semicarbazide trihydrazino triazine.
• Preferred blowing agents include isobutane, HFC- 152a, and mixtures of the foregoing.
• the absorbent foams are optionally perforated to enhance or accelerate permeation of blowing agent from the foam and air into the foam. Such perforation is within the skill in the art, for instance as taught in U.S. Patent Nos. 5,424,016 and 5,585,058.
• additives are optionally incorporated in the resulting foam structure such as stability control agents, nucleating agents, inorganic fillers, pigments, antioxidants, acid scavengers, ultraviolet absorbers, flame retardants, processing aids, extrusion aids,.
• a stability control agent is optionally added to the present foam to enhance dimensional stability.
• Preferred agents include amides and esters of C 10-24 fatty acids. Such agents are seen in U.S. Pat. Nos. 3,644,230 and 4,214,054, which are incorporated herein by reference.
• nucleating agent is optionally added in order to control the size of foam cells.
• Preferred nucleating agents include inorganic substances such as calcium carbonate, talc, clay, titanium oxide, silica, barium sulfate, diatomaceous earth, mixtures of citric acid and sodium bicarbonate,.
• the amount of nucleating agent employed may range from 0.01 to 5 parts by weight per hundred parts by weight of a polymer resin.
• the resulting foam structure is optionally closed-celled or open-celled.
• the open cell content will range from 0 to 100 volume percent as measured according to ASTM D2856-A.
• the resulting absorbent foam structure is substantially noncrosslinked or uncrosslinked, and is optionally is in any physical configuration within the skill in the art, such as extruded sheet, rod, plank, and profiles.
• the stalling material substantially random interpolymer prior to sulfonation comprises from 0.5 to 65, preferably from 5 to 65, more preferably from 10 to 65 mole percent of at least one vinyl or vinylidene aromatic monomer and/or aliphatic or cycloaliphatic vinyl or vinylidene monomer and from 35 to 99.5, preferably from 35 to 95, more preferably from 35 to 90 mole percent of ethylene and/or at least one aliphatic ⁇ -olefin having from 3 to 20 carbon atoms.
• the melt index (I 2 ) of the starting material substantially random interpolymer prior to sulfonation is from 0.01 to 1000, preferably of from 0.3 to 30, more preferably of from 0.5 to 10 g/10 min.
• the molecular weight distribution (M w /M n ) of the starting material substantially random interpolymer prior to sulfonation is from 1.5 to 20, preferably of from 1.8 to 10, more preferably of from 2 to 5.
• the density of the starting material substantially random interpolymer prior to sulfonation is greater than about 0.930, preferably from 0.930 to 1.045, more preferably of from 0.930 to 1.040, most preferably of from 0.930 to 1.030 g/cm 3 .
• the degree of sulfonation of the starting material substantially random interpolymer is from 1.5 to 100, preferably from 15 to 100, more preferably from 30 to 100 mol percent (based on the total number of aromatic rings in the initial substantially random interpolymer) of mono substituted aromatic rings substituted with a sulfonic acid group or a sulfonic acid salt.
• the absorbent polymers compositions of the present invention comprise from
• 10 to 100 preferably from 20 to 100, more preferably from 50 to 100 wt percent, (based on the combined weights of this component and the polymer component other than the sulfonated substantially random interpolymer) of one or more sulfonated substantially random interpolymers of ethylene and/or one or more ⁇ -olefins and one or more vinyl or vinylidene aromatic monomers and/or one or more sterically hindered aliphatic or cycloaliphatic vinyl or vinylidene monomers.
• the sulfonated substantially random interpolymers comprise from 35 to 98.5, preferably from 35 to 85, more preferably from 35 to 70 mol percent of repeating units derived from ethylene and/or said ⁇ -olefin which comprises at least one of propylene, 4-methyl-l-pentene, butene-1, hexene-1 or octene-1.
• the sulfonated substantially random interpolymers comprise from 1.5 to 65 preferably from 15 to 65, more preferably from 30 to 65 mol percent of repeating units derived from said sulfonated vinyl or vinylidene aromatic monomers.
• the sulfonated substantially random interpolymers comprise from 0 to 63.5, preferably from 0 to 50, more preferably from 0 to 35 mol percent of repeating units derived from vinyl or vinylidene aromatic monomers.
• the sulfonated substantially random interpolymers comprise from 0 to 63.5, preferably from 0 to 50, more preferably from 0 to 35 mol percent of repeating units derived from said sterically hindered aliphatic or cycloaliphatic vinyl or vinylidene monomers.
• the sulfonated substantially random interpolymers comprise from 0 to 20 preferably, more preferably mol percent of norbornene, or a C 1-10 alkyl or C 6-1 o aryl substituted norbornene.
• the absorbent polymers compositions of the present invention can also comprise from 0 to 90, preferably from 0 to 80, more preferably from 0 to 50 wt percent of at least one polymer other than said sulfonated substantially random interpolymer (based on the combined weights of this component and the sulfonated substantially random interpolymer).
• compositions of the present invention as binders for the recovery of coal and refractory fines.
• applications using the materials of the present invention as solid acid catalysts including shape selective and optically active catalytic transformations.
• the molecular weight of the polymer compositions for use in the present invention is conveniently indicated using a melt index measurement according to ASTM D-1238, Condition 190°C/2.16 kg (formally known as "Condition
• Sweep width 5000 hz Acquisition time, 3.002 sec Pulse width, 8 ⁇ sec
• Polystyrene has five different types of protons that are distinguishable by proton NMR.
• these protons are labeled b, branch; ⁇ , alpha; o, ortho; m, meta; p, para, as shown in figure 1.
• b branch
• ⁇ alpha
• o ortho
• m meta
• p para
• the NMR spectrum for polystyrene homopolymer includes a resonance centered around a chemical shift of about 7.1 ppm, which is believed to correspond to the three ortho and para protons.
• the spectrum also includes another peak centered around a chemical shift of about 6.6 ppm. That peak corresponds to the two meta protons.
• Other peaks at about 1.5 and 1.9 ppm correspond to the three aliphatic protons (alpha and branch).
• the relative intensities of the resonances for each of these protons were determined by integration.
• the integral corresponding to the resonance at 7.1 ppm was designated PS 7 . ! below. That corresponding to the resonance at 6.6 ppm was designated PS 6 . 6j and that corresponding to the aliphatic protons (integrated from 0.8- 2.5 ppm) was designated PS al .
• the theoretical ratio for PS .j . : PS 6 . 6 : PS a ⁇ is 3:2:3, or 1.5:1:1.5.
• An aliphatic ratio of 2 to 1 is predicted based on the protons labeled ⁇ and b respectively in figure 1. This ratio was also observed when the two aliphatic peaks were integrated separately. Further, the ratio of aromatic to aliphatic protons was measured to be 5 to 3, as predicted from theoretical considerations.
• the 1H NMR spectrum for the ESI interpolymer was then acquired. This spectrum showed resonances centered at about 7.1 ppm, 6.6 ppm and in the aliphatic region. However, the 6.6 ppm peak was relatively much weaker for the ESI interpolymer than for the polystyrene homopolymer. The relative weakness of this peak is believed to occur because the meta protons in the ESI copolymer resonate in the 7.1 ppm region. Thus, the only protons that produce the 6.6 ppm peak are meta protons associated with atactic polystyrene homopolymer that is an impurity in the ESI.
• the peak centered at about 7.1 ppm thus includes ortho, meta and para protons from the aromatic rings in the ESI interpolymer, as well as the ortho and para protons from the aromatic rings in the polystyrene homopolymer impurity.
• the peaks in the aliphatic region include resonances of aliphatic protons from both the ESI interpolymer and the polystyrene homopolymer impurity. Again, the relative intensities of the peaks were determined by integration.
• the peak centered around 7.1 ppm is referred to below as I 7 . 1 , that centered around 6.6 ppm is Lj. 6 and that in the aliphatic regions is Lj.
• I 7 .i includes a component attributable to the aromatic protons of the ESI interpolymer and a component attributable to the ortho and para protons of the aromatic rings of the polystyrene homopolymer impurity.
• J-7.1 Ic7.1 + Ips7.1
• I c7 1 is the intensity of the 7.1 ppm resonance attributable to the aromatic protons in the interpolymer and I ps7.
• ⁇ is the intensity of the 7.1 ppm resonance attributable to the ortho and meta protons of the polystyrene homopolymer.
• Ic7.1 I7.1 - 1 -5(I ⁇ 5. 6 ).
• I pSal the intensity attributable to the aliphatic protons of the polystyrene homopolymer impurity.
• Wt% PS 100% * Wt% S * (I 6 6 /2S). 100 - [Wt% S * ( 2S)]
• the total styrene content was also determined by quantitative Fourier transform infrared spectroscopy (FTIR).
• FTIR quantitative Fourier transform infrared spectroscopy
• PPl is INSPIRETM H700-12 polypropylene (a trademark of and available from The
• TiCl3 «3THF and about 120 ml of THF was added at a fast drip rate about 50 ml of a
• the residue was slurried in 60 ml of mixed hexanes at about 20 °C for approximately 16 hours. The mixture was cooled to about -25 °C for about 1 hour. The solids were collected on a glass frit by vacuum filtration and dried under reduced pressure. The dried solid was placed in a glass fiber thimble and solid extracted continuously with hexanes using a Soxhlet extractor. After 6 hours a crystalline solid was observed in the boiling pot. The mixture was cooled to about -20 °C, isolated by filtration from the cold mixture and dried under reduced pressure to give 1.62 g of a dark crystalline solid. The filtrate was discarded. The solids in the extractor were stirred and the extraction continued with an additional quantity of mixed hexanes to give an additional 0.46 g of the desired product as a dark crystalline solid.
• ESI #'s 1 - 2 were prepared in a continuously operating loop reactor (36.8 gal).
• An Ingersoll-Dresser twin screw pump provided the mixing.
• the reactor ran liquid full at 475 psig (3,275 kPa) with a residence time of approximately 25 minutes.
• Raw materials and catalyst/cocatalyst flows were fed into the suction of the twin screw pump through injectors and Kenics static mixers.
• the twin screw pump discharged into a 2 inch diameter line which supplied two Chemineer-Kenics 10-68 Type BEM Multi- Tube heat exchangers in series.
• the tubes of these exchangers contained twisted tapes to increase heat transfer.
• loop flow returned through the injectors and static mixers to the suction of the pump.
• Heat transfer oil was circulated through the exchangers' jacket to control the loop temperature probe located just prior to the first exchanger.
• the exit stream of the loop reactor was taken off between the two exchangers.
• the flow and solution density of the exit stream was measured by a Micro-MotionTM mass flow meter.
• Solvent feed to the reactor was supplied by two different sources.
• a fresh stream of toluene from an 8480-S-E PulsafeederTM diaphragm pump with rates measured by a Micro-MotionTM mass flow meter was used to provide flush flow for the reactor seals (20 lb/hr (9.1 kg/hr).
• Recycle solvent was mixed with uninhibited styrene monomer on the suction side of five 8480-5-E PulsafeederTM diaphragm pumps in parallel. These five PulsafeederTM pumps supplied solvent and styrene to the reactor at 650 psig (4,583 kPa).
• Fresh styrene flow was measured by a Micro-MotionTM 1 mass flow meter, and total recycle solvent/styrene flow was measured by a separate Micro- MotionTM mass flow meter.
• Ethylene was supplied to the reactor at 687 psig (4,838 kPa).
• the ethylene stream was measured by a Micro-MotionTM mass flow meter.
• a Brooks flow meter/controller was used to deliver hydrogen into the ethylene stream at the outlet of the ethylene control valve.
• the temperature of the entire feed stream as it entered the reactor loop was lowered to 2°C by an exchanger with -10°C glycol on the jacket.
• Preparation of the three catalyst components took place in three separate tanks. Fresh solvent and concentrated catalyst/cocatalyst premix were added and mixed into their respective run tanks and fed into the reactor via variable speed 680-S-AEN7 PulsafeederTM diaphragm pumps.
• the three component catalyst system entered the reactor loop through an injector and static mixer into the suction side of the twin screw pump.
• the raw material feed stream was also fed into the reactor loop through an injector and static mixer downstream of the catalyst injection point but upstream of the twin screw pump suction.
• This flashed polymer entered the first of two hot oil jacketed devolatilizers.
• the volatiles flashing from the first devolatizer were condensed with a glycol jacketed exchanger, passed through the suction of a vacuum pump, and were discharged to the solvent and styrene/ethylene separation vessel. Solvent and styrene were removed from the bottom of this vessel as recycle solvent while ethylene exhausted from the top.
• the ethylene stream was measured with a Micro-MotionTM mass flow meter. The measurement of vented ethylene plus a calculation of the dissolved gases in the solvent styrene stream were used to calculate the ethylene conversion.
• the polymer and remaining solvent separated in the devolatilizer was pumped with a gear pump to a second devolatizer.
• the pressure in the second devolatizer was operated at 5 mmHg (0.7 kPa) absolute pressure to flash the remaining solvent.
• This solvent was condensed in a glycol heat exchanger, pumped through another vacuum pump, and exported to a waste tank for disposal.
• the dry polymer ( ⁇ 1000 ppm total volatiles) was pumped with a gear pump to an underwater pelletizer with 6-hole die, pelletized, spin-dried, and collected in 1000 lb boxes.
• Table 1 Preparation Conditions for ESI 2*
• Catalyst A is ;(lH-cyclopenta[l]phenanthrene-2-yl)dimethyl(t-butylamido)-silanetitanium 1,4-diphenylbutadiene)
• Cocatalyst B is tris(pentafluorophenyl)borane, (CAS# 001109-15-5),.
• c a modified methylaluminoxane commercially available from Akzo Nobel as MMAO-3A (CAS# 146905-79-5) *ESI 1 was prepared in a similar manner to ESI 2.
• Disks (5 mil thick; 25mm diameter) prepared from extruded film of ESI 1 were placed in 4 ounce glass vials followed by 25 ml of swelling solvents (hexanes, Isopar C, Isopar M). The disks were allowed to swell for 15 minutes; followed by addition of an equivalent volume of 30 percent oleum. The oleum formed a separate lower phase to the swelling solvent; the disk remained at the interface between the two fluids. After 5 minutes, the disks were removed with tweezers from the vial and immersed into 1 Normal aqueous sodium hydroxide in a beaker.
• swelling solvents hexanes, Isopar C, Isopar M
• Example 2 a,b,c Using procedure as described in Example 1, three ESI 1 disks (Examples 2 a,b,c) were exposed to 15 minutes of hexane solvent followed by 5, 10, and 15 minutes of 30 percent oleum exposure, respectively. After neutralization and drying, the weight gain was 7, 18, and 24 percent, respectively.
• sulfonated disks (Exs 2a, b, and c), after water exposure gained 109, 143, and 231 percent weight, respectively. The percent weight increase from sulfonation/ neutralization versus water uptake is shown in Table 4.
• the fibers were fabricated using two 1.25 inch diameter extruders which fed two gear pumps each pumping at a rate of 6 cm 3 /rev. The gear pumps pushed the material through a spin pack containing a filter and a multiple hole spinneret.
• the spin head temperature was typically from about 285°C, and varied depending upon the melting point and degradation temperature of the polymer components being spun. Generally the higher the molecular weight of the polymers, the higher the melt temperature.
• Quench air (about 10°C) was used to help the melt spun fibers cool.
• the quench air was located just below the spinneret and blows air perpendicularly across the length of the fibers as they are extruded.
• the fibers were collected on a series of godet rolls to produce the yarn.
• the first godet located about 2.5 meters below the spinneret die and having a diameter of about 6 inches (15.24 cm).
• the fiber was tested on an Instron tensile testing device equipped with a small plastic jaw on the cross-head (the jaw has a weight of about six gms) and a 500 gram load cell.
• the jaws are set 1 inch (2.54 cm) apart.
• the cross head speed is set at 5 inches/minute (12.7 cm/minute).
• a single fiber is loaded into the Instron jaws for testing.
• the fiber is then stretched to 100 percent of strain (that is, it is stretched another 1 inch), where the tenacity is recorded.
• the fiber is allowed to return to the original Instron setting (where the jaws are again 1 inch apart) and the fiber is again pulled.
• the strain is recorded and the percent permanent set is calculated.
• a fiber pulled for the second time which did not provide stress resistance (that is, pull a load) until it had traveled 0.1 inches (0.25 cm) would have a percent permanent set is of 10 percent, that is, the percent of strain at which the fiber begins to provide stress resistance.
• the numerical difference between the percent permanent set and 100 percent is known as the percent elastic recovery.
• a fiber having a permanent set of 10 percent will have a 90 percent elastic recovery.
• percent permanent set the fiber is pulled to 100 percent strain and the tenacity recorded.
• the fiber pulling process is repeated several times, with the percent permanent set recorded each time and the 100 percent strain tenacity recorded as well.
• the fiber is pulled to its breaking point and the ultimate breaking tenacity and elongation recorded.
• the tow was cut into 1.5-2.5 cm lengths, then place in a Waring Blender, combined with water (ca 500 grams water/100 grams chopped tow) and stirred at high speed for 2 minutes. The fibrillated chopped tow was then dried in a forced air oven overnight at 50°C.
• Fibrillated chopped tow was placed into three 6 inch long by 1 inch diameter open cylinder made from coarse stainless screen material.
• the screens were then sequentially (as defined below) immersed in a series of beakers containing excess hexane swelling agent, 30 percent oleum, 100 percent sulfuric acid, 50 percent sulfuric acid, 1 normal aqueous sodium hydroxide for the indicated times.

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