Abstract: A thermoplastic polyurethane/olefin-graft polymer blend with an optional compatibilizing polymer that demonstrates improved tensile strength, compression set and abrasion resistance properties relative to a blend prepared from the same thermoplastic polyurethane and an ungrafted version of the olefin-graft polymer.

Abstract: A poly(arylene ether)-polyolefin composition is prepared by melt-blending a poly (arylene ether), a poly(alkenyl aromatic) resin, a hydrogenated block copolymer of an alkenyl aromatic compound and a conjugated diene, and an unhydrogenated block copolymer of an alkenyl aromatic compound and a conjugated diene to form a first blend, and melt-blending the first blend and a polyolefin to form a second blend. Reinforcing fillers may, optionally, be added during formation of the second blend or in an additional step. Multiple mixing elements, low throughput, and high extruder rotations per minute may be used to achieve high energy mixing of the first and second blends. Compositions prepared by the method exhibit an improved balance of impact strength, stiffness, and heat resistance, as well as reduced variability of physical properties.

Abstract: The invention relates to metallized, unsaturated polymer anions stabilized by coordinate bonding and having a high proportion of cis double bonds, to a process for the preparation thereof and also to the use of the new polymer anions for the preparation of graft polymers that can be obtained by reaction of the unsaturated polymer anions with anionically polymerisable, non-polar monomers. From the graft polymers that are prepared in this way the most diverse rubber mouldings can be produced by appropriate vulcanization processes.

Abstract: A polyoxymethylene resin composition is provided which comprises a polyoxymethylene resin (A), a silicone compound-grafted polyolefinic resin (B-1) and a silicone compound (B-2), the amount of the silicone compound-grafted polyolefinic resin (B1) being 0.05 to 10 parts by weight on the basis of 100 parts by weight of the polyoxymethylene resin (A), and the ratio of (B1)/(B2) by weight in the composition being 99/1 to 70/30.

Abstract: A weatherseal or belt-line seal for a vehicle is formed by extrusion of an olefin-based thermoplastic elastomer or vulcanizate (first TPV) as an elongate body of arbitrary length and cross-section. The cross-section is adapted for use in a particular location in the opening of a structure to be protected against wind and rain, for example around the glass of a window in a vehicle's door, or around the opening (at the periphery) in which the door is closed, so as to present at least one sealing surface against which the glass or door may be abutted to provide a seal against the elements. A slip-coating is co-extruded onto one or more longitudinal sealing surfaces of the body; the slip-coating contains a novel compatibilizer which allows thermoplastic polyurethane (TPU) to be chemically bonded to a graft copolymer of polypropylene (PP) and a compound having two anhydride groups. The reaction product of the grafted PP and the TPU effects a thermal bond with the sealing surface of the body.

Abstract: The molding composition comprises components A to C and, if desired, D: a: as component A, from 20 to 94% by weight of a hard component made from one or more copolymers of styrene and/or &agr;-methylstyrene with acrylonitrile, where the proportion of acrylonitrile is from 10 to 50% by weight, b: from 5 to 70% by weight of at least one graft copolymer B, made from b1: as component B1, from 10 to 90% by weight of at least one elastomeric particulate graft base with a glass transition temperature below 0° C., and b2: as component B2, from 10 to 90% by weight of at least one graft made from a copolymer of styrene and/or &agr;-methylstyrene with acrylonitrile, where the proportion of acrylonitrile is from 10 to 50% by weight, c: as component C, from 0.

Abstract: There is disclosed a process for producing films from ethylene-&agr;-olefin interpolymers, which films have, in combination, the properties of improved surface haze, improved stiffness, and improved color. The process involves incorporating from about 0.1 to less than 1% by weight, of a functionalized ethylene homopolymer or functionalized ethylene interpolymer into an ethylene-&agr;-olefin interpolymer-containing composition, and forming a film from the composition.

Abstract: The present invention provides adhesive compositions, particularly pressure sensitive adhesive compositions, comprised of from 30 weight percent to 70 weight percent of water insoluble graft copolymers dispersed in an aqueous medium. The graft copolymers are comprised of (i) from 1 weight percent to 30 weight percent of macromonomer, based on the total weight of the copolymer, wherein the macromonomer is water insoluble and has a number average molecular weight of from 2,000 to 50,000 g/mole and comprises from 85 to 100 weight percent polymerized units of at least one first ethylenically unsaturated monomer, 5 mole percent or less of polymerized mercapto-olefin compounds, and 10 weight percent or less polymerized acid-containing monomer; and (ii) from 70 weight percent to 99 weight percent of polymerized units of at least one second ethylenically unsaturated monomer, based on the total weight of the copolymer. In certain preferred embodiments, the adhesive compositions further comprise from 0.

Abstract: The invention provides a binder resin and a primer composition, paint composition, ink composition an adhesive composition with excellent gasohol resistance, adherence, weather resistance, etc. to polyolefinic resins and relates to a binder resin for polyolefinic resins comprising carboxyl group-containing chlorinated polyolefin (II), which contains not more than 2% of a component with molecular weight of 2,000 or lower and which has a ratio of weight average molecular weight (Mw) to number average molecular weight (Mn), that is the value Mw/Mn of not more than 4.

Abstract: The invention relates to a nanocomposite material on the basis of clay having a layered structure and a cation exchange capacity of from 30-250 milliequivalents per 100 gram, a polymeric matrix and a block copolymer or a graft copolymer, which block copolymer or graft copolymer comprises one or more first structural units (A), which are compatible with the clay and one or more second structural units (B), which are compatible with the polymeric matrix.

Abstract: Disclosed herein is a golf ball with a cover or mantle, or both, formed from a composition comprising a polyamide-ionomer graft copolymer and a method of making the same. Polyamide-ionomer graft copolymers include a polyamide component and an ionomeric component. In a preferred form, polyamide-ionomer graft copolymers have a polyamide component backbone and ionomeric components grafted thereto. Golf balls according to the invention may also be formed from a composition or material that includes a blend of a polyamide-ionomer graft copolymer and an ionomer. Such blends are preferably employed as a mantle or a cover of a golf ball. The cover composition has excellent durability and resistance to cracking, even at cold temperatures. Materials comprising polyamide-ionomer graft copolymer are a useful substitute for an ionomer golf ball cover, particularly when a low spin golf ball is desired.

Abstract: The objective of the present invention lies in providing a resin composition which enables water vapor permeability to be controlled over a broad range while maintaining a high gas permeability, together with molded articles or packaging materials comprising said composition, in particular a packaging material for foodstuffs like fruit and vegetables. A thermoplastic resin composition which is characterized in that a polymer (A) containing polyether chains as structural units, polyethylene (B) of density as specified in JIS K6760 of less than 0.91 g/cm3 and a compatibilizing agent (C) are blended together in proportions by weight of A/B/C=99.5 to 0.5/0.5 to 99.5/0 to 30 (where A+B+C=100); and molded articles comprising said composition, in particular a packaging material for vegetables and fruit cultivation or foodstuffs storage.

Abstract: Materials ranging from impact-modified thermoplastics to thermoplastic elastomers (TPE) can be obtained from blends of phase compatibility-treated recycled thermoset rubber with thermoplastic polymers by varying the ratio of components in the blend, or by changing the components themselves. The rubber component may include carbon black, or other fillers and additives, and it may be selected from among a variety of thermoset rubbers, both natural and synthetic. The thermoset rubber component can be obtained from a rubber material recycled according to a variety of known techniques. The thermoplastic component can be virtually any suitable polymer, the properties of which can be advantageously modified by combination with a rubber. Polyolefins are among the more preferred thermoplastic components.

Abstract: An elastic-thermoplastic graft polymer prepared by a multi-stage free radical polymerization is described. The elastic-thermoplastic graft polymer is prepared by polymerizing (i) one or more monomers containing vinyl groups, and (ii) at least one molecular weight regulating compound, in the presence of (iii) at least one rubber in latex form. The ratio of monomers (M) to the molecular weight regulating compound (MWR) is altered throughout the various stages of the polymerization method. The M:MWR ratio is: from 50:1 to 400:1 in the first stage; from 100:1 to 800:1 in the second stage; and from 200:1 to 2000:1 in the third stage of the polymerization. In at least one further reaction stage of the polymerization, the monomers, in the absence of the molecular weight regulating compound, are polymerized in the presence of the rubber. This further reaction stage occurs before the first stage and/or after the third stage of the polymerization.

Abstract: Thermosetting polymers and the electrical laminates made therefrom are disclosed. The polymer comprises the cross-linked product of: a) one or more ethylenically unsaturated aromatic monomers, optionally containing a halogenated monomer to impart fire retardation, and b) a vinyl-terminated polybutadiene or butadiene-styrene copolymer containing either a urethane or an ester group. It has been discovered that an unexpected combination of thermal, electrical, and mechanical properties are obtained from the composition recited herein. The composition is ideally suited as a matrix polymer for electrical substrate applications.

Abstract: Present invention is a resin composition obtained by reacting polyolefin (A) with a (co)polymer (B) prepared from a copolymerizable monomer mixture (C) comprising an &agr;,&bgr;-monoethylenically unsaturated monomer and other copolymerizable monomers in a weight ratio (A)/(B)=1/9-9/1 under radical generation in an organic solvent, or by polymerizing a copolymerizable monomer mixture (C) comprising an &agr;,&bgr;-monoethylenically unsaturated monomer and other copolymerizable monomers in the presence of polyolefin (A) in a weight ratio (A)/(C)=1/9-9/1 in an organic solvent and successively by reacting the obtained reaction mass under radical generation; and the resin composition has good solution stability, does not cause liquid phase separation or solid precipitation, can be used as intact, is excellent in sprayability at high concentration, and, specifically, has novel function and effect that adhesion to polyolefin molded articles is excellent; and the resin composition can be favorably used f

Abstract: The invention provides a resin composition comprising a polyphenylene ether-based resin and a polyolefin resin, having no interlayer peeling and exhibiting excellent heat resistance and dynamic properties such as impact resistance, rigidity and tensile breaking elongation.

Abstract: An aromatic carbonate polymer composition having improved thermal stability consisting of an aromatic carbonate polymer such as a polycarbonate or polycarbonate/polyester blend and an impact modifier which is free of alkali materials which catalytically degrade a polycarbonate. Also an impact modifier which is preferably of a shell-core structure prepared by the emulsion polymerization process and has a pH of about 3 to about 8. A preferred emulsifier is an alkyl sulfonate having an alkyl group of C6-C18 carbons.

Abstract: The present invention relates to shape deformable materials, which are capable of (1) being deformed, (2) storing an amount of shape deformation, and (3) recovering at least a portion of the shape deformation when exposed to a humid environment. The shape deformable materials can advantageously be in the form of films, fibers, filaments, strands, nonwovens, and pre-molded elements. The shape deformable materials of the present invention may be used to form products, which are both disposable and reusable. More specifically, the shape deformable materials of the present invention may be used to produce products such as disposable diapers, training pants, incontinence products, and feminine care products.

Abstract: The present invention relates to shape deformable materials, which are capable of (1) being deformed, (2) storing an amount of shape deformation, and (3) recovering at least a portion of the shape deformation when exposed to a humid environment. The shape deformable materials can advantageously be in the form of films, fibers, filaments, strands, nonwovens, and pre-molded elements. The shape deformable materials of the present invention may be used to form products, which are both disposable and reusable. More specifically, the shape deformable materials of the present invention may be used to produce products such as disposable diapers, training pants, incontinence products, and feminine care products.

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Abstract: An orientation layer of an acrylic copolymer is used to orient rod-like liquid crystal molecules perpendicularly to rubbing direction.

Abstract: A fitting composition capable of fitting a body-worn tool to be used in contact with skin, such as spectacles, a hearing aid, and an artificial limb, suitably to the body shape of individual wearer and thereby realizing the function of the body-worn tool in a steady state, as well as providing an excellent wear-feeling, a body-worn tool produced using the same, and a method of producing the same. The fitting composition for body-worn tools to be used in contact with skin including (a) a thermoplastic block copolymer having at least one polymer block (A) mainly composed of an aromatic vinyl compound and at least one elastic polymer block (B); (b) a (meth)acrylic monomer; and (c) a polymerization initiator.

Abstract: Molecular chemical and/or biological sensors that exhibit a very high density of sensing functionality and which are applicable to a wide variety of different analytes, and enable rapid, convenient and economical detection of analytes are prepared by reacting a dendritic polymer with a diacetylene reagent wherein the diacetylene functional groups are subsequently intramolecularly polymerized to form segments having alternating conjugated double and triple bonds. Sensory groups that can bind with an analyte are bonded to the acetylene monomer units to form molecular sensors that produce observable and measurable color changes when an analyte binds with the sensory groups.

Abstract: The rheological properties of a crosslinkable resin system are modified by the presence of a side chain crystalline (SCC) polymer (or a similar crystalline polymer which melts over a narrow temperature range). The polymer dissolves in the curable system at temperatures above the melting point of the crystalline polymer (Tp), but when the system is then cooled to a temperature below Tp, at least partially forms a separate phase in the curable system. Below Tp, this separate phase substantially increases the viscosity of the curable system (i.e. makes it thicker than the same system without the crystalline polymer). This is particularly valuable for sheet molding composites (SMCs) in which the increase in viscosity makes the composites less tacky, and for dry film resists (DFRs). Above Tp, the curable system containing the dissolved crystalline polymer has a viscosity which is substantially less than its viscosity below Tp.

Abstract: Thermoplastic elastomers containing hard segments formed from polyalkylenes and soft segments formed from elastomeric polymers near their gelation point are formed. Compositions containing these materials are elastomeric and exhibit excellent damping capabilities over a wide range of temperatures and frequencies.

Abstract: A thermoplastic composition includes a poly(arylene ether), a poly(alkenyl aromatic) resin, a polyolefin, a hydrogenated block copolymer of alkenyl aromatic compound and a conjugated diene having an alkenyl aromatic content of about 40 to about 90 weight percent, and an unhydrogenated block copolymer of an alkenyl aromatic compound and a conjugated diene. The composition exhibits excellent stiffness-impact strength balance, low property variability, and long melt hang time.

Abstract: The present invention is a blend of a polymeric hydrocarbon and a thermoplastic polyurethane which is compatibilized a polymeric hydrocarbon that contains low concentrations of isocyanate reactive group. The compatibilizer can be prepared by reacting a modified polymer having pendant or incorporated amine-reactive groups with a hydroxyl amine, a diamine, or a polyethermonoamine. The compatibilized blend may further include a non-TPU engineering thermoplastic to form compatible blends of the polymeric hydrocarbon and the non-TPU engineering thermoplastic. In this case, the TPU is used as a co-compatibilizer.

Abstract: A polyether monoamine containing from about 36 to about 44 ethylene oxide units and from about 1 to about 6 propylene oxide units is useful as a reactant with functionalized polypropylene such as maleated polypropylene to form a reaction product blended with polypropylene.

Abstract: The invention relates to a composition based on an ethylene-vinyl alcohol copolymer comprising: 50 to 98% by weight of an EVOH copolymer 1 to 50% by weight of a polyethylene (A) 1 to 15% by weight of a polymer (B) resulting from the reaction (i) of a copolymer (B1) of ethylene and of an unsaturated monomer X grafted or copolymerized with (ii) a polyamide (B2). It also relates to a multilayer structure comprising a layer consisting of this composition. This structure is useful for making packaging. The composition of the invention also adheres well to PET, this property being useful in coinjection to make bioriented preforms.

Abstract: To provide a thermoplastic polyester resin composition which has a very good durability to alkaline solutions for a long period of time. That is, a thermoplastic polyester resin composition, wherein a thermoplastic polyester resin (A) is compounded with 1-25% by weight (in the total composition) of impact resistance rendering materials (B), 0.1-15% by weight (in the total composition) of a silicone compound and/or a fluorine compound (C), 1-50% by weight (in the total composition) of an inorganic filler (D), and 0.1-10% by weight of at least one polyfunctional compound (E) selected from the group consisting of an epoxy compound, an isocyanate compound and a carboxylic acid dianhydride. A molded article of the present invention has anti-stress properties even in a weld part thereof.

Abstract: Compositions which have substantial weatherability and impact resistance include a substantially uniform blend of an acrylonitrile/styrene/acrylic polymeric material and a component selected from (A) polymeric materials including units derived from ethylene, carbon monoxide and copolymerizable ethylenically unsaturated organic compounds, (B) graft polymer components including ethylene-propylene-non-conjugated diene terpolymers grafted with styrene and acrylonitrile monomers, and mixtures thereof. Methods for making such compositions include forming a substantially uniform physical mixture of such polymeric material and component.

Abstract: An elastic-thermoplastic graft polymer prepared by a multi-stage free radical polymerization is described. The elastic-thermoplastic graft polymer is prepared by polymerizing (i) one or more monomers containing vinyl groups, and (ii) at least one molecular weight regulating compound, in the presence of (iii) at least one rubber in latex form. The ratio of monomers (M) to the molecular weight regulating compound (MWR) is altered throughout the various stages of the polymerization method. The M:MWR ratio is: from 50:1 to 400:1 in the first stage; from 100:1 to 800:1 in the second stage; and from 200:1 to 2000:1 in the third stage of the polymerization. In at least one further reaction stage of the polymerization, the monomers, in the absence of the molecular weight regulating compound, are polymerized in the presence of the rubber. This further reaction stage occurs before the first stage and/or after the third stage of the polymerization.

Abstract: An object of the present invention is to substantially improve the compatibility between a radical copolymerizable unsaturated resin and an addition polymerized polymer (thermoplastic resin) which is added for the purpose of low profile and improvement of physical properties. The present invention provides a compatibilizing agent for compatibilizing a radical copolymerizable unsaturated resin with an addition polymerized polymer, characterized in that said compatibilizing agent is a graft copolymer (A) which contains a styrene monomer as a principal component, and has a principal chain (A1) consisting of a copolymer with a (meth)acrylate monomer and a side chain (A2) selected from a ring-opening polymerized polyether side chain consisting of a polyoxyalkylene ether, a polyester side chain, and a polycarbonate side chain, the side chain (A2) being bonded to the principal chain.

Abstract: The object of the present invention is to provide a molding thermoplastic resin material giving resin mold whose quality and value are substantially equal to original resin mold even in a case where said resin mold is recycled.

Abstract: The invention relates to compatibilized blends comprising a non-polar thermoplastic elastomer, a polar thermoplastic polymer selected from thermoplastic polyurethane (TPU), chloro containing polymers, fluoro containing polymers, polyesters, acrylonitrile-butadiene-styrene copolymers, styrene-acrylonitrile copolymers, styrene-maleic anhydride copolymer, polyacetal, polycarbonate, polyphenylene oxide, and a suitable compatibilizer.

Abstract: The invention relates to polyazacycloalkanes having 3, 4 or 5 nitrogen atoms, tri-, tetra- or penta-azamacrocyclic transition metal complexes and processes for the production of said polyazacycloalkanes. The object of the invention is to form polyazacycloalkanes able to trap metal cations and in particular U, Pu, Am, Ce, Eu, Al, Gd, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ag, Cd, Sn, Au, Mg or Pb or complexes able to trap in particular oxygen in a gaseous mixture. The invention more particularly applies to the treatment of liquid effluents from nuclear power stations.

Abstract: The invention provides a combination of specific graft polymers produced by emulsion polymerization on the basis of a mixture of three rubber latices with ABS polymers produced by solution, bulk or suspension polymerization, by which products with extremely high impact strength values are obtained.

Abstract: Porous polyolefins are especially efficiently free-radically grafted using (fluorinated alkyl)olefins, vinylsilanes or certain carboxylic acids or their esters as the grafting molecules. The use of a solvent to swell the porous polyolefin is sometimes advantageous.

Abstract: A thermoplastic molding composition comprising a grafted acrylate rubber (ASA) and a gloss reducing agent and a process for making the same are disclosed. The gloss reducing agent is the reaction product of (i) a compound having two or more epoxy groups per molecule and (ii) a compound having two or more amine groups per molecule, with the proviso that the total of epoxy groups of (i) and amine groups of (ii) per molecule is greater than 4. The gloss reducing agent may be either incorporated in ASA as the reaction product of (i) and (ii) or, in the alternative, formed upon the reaction of (i) with (ii) in the course of the thermal processing of the a blend containing ASA, (i) and (ii).

Abstract: This invention relates to grafted ethylene-higher &agr;-olefin polymers and blends thereof. Preferred grafted ethylene-higher &agr;-olefin polymers are multimodal EPDM's having 5-40 weight % of a higher molecular weight, higher ethylene content, lower diene content fraction grafted with maleic anhydride. These polymers can then be used as modifiers for additional polymers such as polyamides, polyesters, and other EPDM's.

Abstract: A thermoplastic molding composition having improved mechanical properties is disclosed. The ABS composition that comprise a graft rubber polymer obtained by emulsion polymerization in the presence of specifically defined butadiene polymer latices and a rubber-free copolymer is suitable for making molded articles.

Abstract: A distinctive graft copolymer is made by dissolving an unsaturated polyester resin in various vinyl monomers (methyl methacrylate, styrene, etc.). The monomer/unsaturated polyester solution is then miniemulsion polymerized to form a latex consisting of submicron particles of polymer with the polyester grafted onto the polymer backbone. The latex can be applied to a substrate, which on drying forms a polymeric film with good film properties. The latex can be used in a latex paint formulation in place of an acrylate, acetate or styrene-divinyl benzene latex. In this way it is possible to produce water-borne unsaturated polyester coatings which combine the film hardness properties of an unsaturated polyester coating with easy application and cleanup. The coating will beneficially lack organic solvent exposure of typical polyester coatings.

Abstract: Thermosetting polymers and the electrical laminates made therefrom are disclosed. The polymer comprises the cross-linked product of: a) one or more ethylenically unsaturated aromatic monomers, optionally containing a halogenated monomer to impart fire retardation, and b) a vinyl-terminated polybutadiene or butadiene-styrene copolymer containing either a urethane or an ester group. It has been discovered that an unexpected combination of thermal, electrical, and mechanical properties are obtained from the composition recited herein. The composition is ideally suited as a matrix polymer for electrical substrate applications.

Abstract: In a dispersion containing acrylic polymer microparticles, particularly useful in automotive coatings, the dispersion is formed by free radical addition copolymerization of unsaturated monomers in a hydrocarbon dispersing medium in the presence of first and second polymeric dispersion stabilizers. The first polymeric dispersion stabilizer has an acrylic backbone and polyester side chains, and the second polymeric dispersion stabilizer is a branched polyester formed from the reaction of polyol, polyacid or anhydride, and fatty acid.

Abstract: A weatherseal or belt-line seal for a vehicle is formed by extrusion of an olefin-based thermoplastic elastomer or vulcanizate (first TPV) as an elongate body of arbitrary length and cross-section. The cross-section is adapted for use in a particular location in the opening of a structure to be protected against wind and rain, for example around the glass of a window in a vehicle's door, or around the opening (at the periphery) in which the door is closed, so as to present at least one sealing surface against which the glass or door may be abutted to provide a seal against the elements. A slip-coating is co-extruded onto one or more longitudinal sealing surfaces of the body; the slip-coating contains a novel compatibilizer which allows thermoplastic polyurethane (TPU) to be chemically bonded to a graft copolymer of polypropylene (PP) and a compound having two anhydride groups. The reaction product of the grafted PP and the TPU effects a thermal bond with the sealing surface of the body.

Abstract: This invention relates to a process for stabilizing and at the same time phase compatibilising plastics or plastic compositions by incorporating polymeric compounds obtainable by reacting a compound selected from the group consisting of the sterically hindered phenols, sterically hindered amines, lactones, sulfides, phosphites, benzotriazoles, benzophenones and 2-(2-hydroxyphenyl)-1,3,5-triazines, which compounds contain at least one reactive group, with a compatibilisator.

Abstract: The present invention is generally directed to a process for forming a diene-rubber grafted centipede polymer. The process includes copolymerizing a copolymer comprising a maleimide and at least one block chosen from the group consisting of vinyl aromatic hydrocarbons, R1R2ethylenes, or alkyl vinyl ethers with an amine. The amine is further functionalized with at least one functional group capable of grafting to a diene rubber. The copolymer is cocured with a diene rubber to form the diene-rubber grafted centipede polymer.

Abstract: A polymeric gel composition comprising a polymer including an anhydride unit and an alkenyl unit, a crosslinking agent, a maleated polyalkylene, an extender, and an organic fatty acid is provided. The polymeric gel composition has superior high-temperature stability, mechanical strength, and moldability.

Abstract: Synthetic polymers having moieties capable of covalent or hydrogen bonding to cellulose and one or more amphiphilic moieties are disclosed. These polymers are capable of providing two distinct properties to paper products, such as tissues, which properties heretofore have been imparted through the use of at least two different molecules. The backbone of these synthetic polymers is based on modified vinyl polymers, such as polyvinyl alcohol, polyacrylamides and polyacrylic acids.