Abstract: The present invention relates to an acrylic pressure sensitive adhesive composition containing ester plasticizer having at least one of ether linkages in the molecule represented by formula 1, alkali metallic salt and quaternary ammonium salt together and polarizer and LCD using the same. The acrylic pressure sensitive adhesive composition of the present invention for polarizer has improved antistatic property, owing to the synergy effect of ester plasticizer having one or more ether linkages, alkali metallic salt and quaternary ammonium salt, in addition to the excellent adhesive force and durability. In particular, the acrylic pressure sensitive adhesive composition provided by the present invention shows excellent durability and improved antistatic property by adding quaternary ammonium salt containing weakly coordinated anions.

Abstract: Emulsion paint type damping coatings show an excellent film forming property even if it leaves at low temperature from 5 to 20° C. It does not generate a defective coated film like swellings after baking drying and brings out an excellent damping performance within a range of 20 to 60° C. That is, it contains one or more than two kinds of organic chemicals within a range of 0.5% to 5% by weight in total and the MFT, the minimum film forming temperature of the entire resin emulsion is within a range of 5 to 15° C. and the boiling point for a film forming assistant is within a range of 150 to 240° C., thus, it enables to obtain an excellent film forming property at 5° C. and even in baking drying and does not generate a defective coated film like swellings as well. As a result, emulsion paint type damping coatings bring out an excellent damping performance within a range of 20 to 60° C.

Abstract: The present invention is drawn to passivated pigment suspensions, methods of forming passivated pigment suspensions, and ink sets based thereupon. The coated pigment suspension can comprise a liquid vehicle and a passivated pigment suspended in the liquid vehicle. The coated pigment can include a pigment core, on which is deposited a passivation layer comprising a polymer precursor synthesized while separate from the pigment. A polymer encapsulation layer may be attached to or deposited on the passivation layer.

Abstract: A method for producing a modified conjugated diene polymer includes a step (A) carrying out a primary modification reaction that reacts a heterocumulene compound having two or more specific functional groups with a conjugated diene polymer having a vinyl content of below 10% and a cis-1,4-bond content of 75% or more and possessing an active end to obtain a primary-modified conjugated diene polymer, and a step (B) carrying out a secondary modification reaction that reacts an active hydrogen-containing compound that includes one or more functional groups selected from the group consisting of an amino group, an imino group, a mercapto group, and a hydroxyl group with the primary-modified conjugated diene polymer to obtain a secondary-modified conjugated diene polymer. The method can produce a modified conjugated diene polymer that exhibits low heat build-up (low fuel consumption) and excellent wear resistance.

Abstract: A nitrile copolymer rubber composition obtained by coagulation of a nitrile copolymer latex composition comprised of a latex of a nitrile copolymer rubber (A) having ?,?-ethylenically unsaturated nitrile monomer units in 55 to 80 wt % and cationic monomer units and/or monomer units able to form cations in which an inorganic filler (B) is dispersed is provided. Note that, preferably, the inorganic filler is a clay. According to the present invention, a nitrile copolymer rubber composition giving a nitrile copolymer rubber cross-linked product with an extremely low gasoline permeability and superior in sour gasoline resistance can be provided.

Abstract: A process for producing a modified polymer which increases low heat buildup and reinforcing capability of a rubber composition and which has excellent abrasion resistance, mechanical characteristics, and processability; a modified polymer obtained by the process; and a rubber composition using the modified polymer are provided. The process comprises a step of carrying out a modification reaction on the active end of a conjugated diene polymer having a vinyl content of below 10%, a cis-1,4 bond content of 75% or higher, and an active end, using an alkoxysilane compound, and a step of carrying out a condensation reaction in the presence of a condensation accelerator comprising a compound of an element belonging to at least one of the groups 4A (excluding Ti), 2B, 3B, and 5B of the periodic table.

Abstract: The present invention provides a rubber composition having more improved low heat build-up property and abrasion resistance, especially a rubber composition useful for the rubber composition used for a tread of tire, and the present invention also provides a tire having a tread prepared using the rubber composition. The rubber composition is one comprising 15 to 150 parts by weight of silica on the basis of 100 parts by weight of a rubber component, wherein the rubber component comprises not less than 10% by weight of a butadiene rubber which has a vinyl content of not more than 35% by weight and is modified with an un-substituted aminosilane compound.

Abstract: In one aspect, the invention includes an aqueous composition for coating articles including isocyanate resins. The coating composition includes from about 50% to about 100% by weight of at least one thermoplastic acrylic polymer; from about 0.1% to about 20% by weight titanium dioxide; and water. The composition has a basic pH, a solids ratio of from about 58% to about 69% by weight, and is substantially free of quartz pigments.

Abstract: A resin molding material for making pulleys containing a novolac type phenolic resin, a glass fiber, an inorganic substrate other than the glass fiber, and an elastomer is described. The novolac type phenolic resin, ranges from 25% by weight to 45% by weight, the glass fiber together with the inorganic substrate other than the glass fiber ranges from 45% by weight to 65% by weight, and the elastomer ranges from 0.5% by weight to 5% by weight, relative to the entire molding material and are blended together. As the inorganic substrate other than the glass fiber, for example, calcium carbonate is used. As the elastomer, for example, NBR is used. The phenolic resin molding material is molded to obtain a resin pulley.

Abstract: A composition for creating a perfect bead of caulk by spraying the substance on a caulk line of any type of caulk and smoothing the line with an implement. The compound provides for the release of caulking agents thereby reducing the coefficient of friction at the surface of the caulk in order to allow the use of a finger or tool to create a symmetric and aesthetically pleasing bead of caulk. The invention is non-hazardous, does not stain or leave a residue on the caulk line or surrounding surfaces, can be painted, can be used with any type of caulk. The release agent comprises a co-solvent, a carrier, a surfactant, a polymer, a defoamer, a coupling agent, and a corrosion inhibitor to optimize the composition for the ideal spraying application.

Abstract: Thermoplastic compositions comprising polyacrylonitriles that contain greater than 90% acrylonitrile as monomer, or copolymers of such polyacrylonitriles with an olefinic unsaturated co-monomer, can be formed by the use of certain compatibilizers and/or thermal stabilizers. Other thermoplastic compositions comprising the high nitrile polyacrylonitriles can be obtained by melt blending the polyacrylonitriles with certain aromatic engineering thermoplastic polymers in the presence of compatibilizers and thermal stabilizers. All of the foregoing high nitrile compositions have been found to possess good optical and gas barrier properties, and good stress crack resistance.

Abstract: A laser-weldable composition is disclosed, comprising, based on the total weight of the laser-weldable composition, more than zero to 99.95 weight percent of a thermoplastic polymer composition; from 0.00001 to 5 weight percent of a near-infrared absorbing material; from 0.0 to 0.02 weight percent of carbon black; and from 0.05 to 20 weight percent of a white pigment.

Abstract: The present invention provides a glass fiber reinforced polycarbonate resin composition having good flowability and excellent impact resistance. The resin composition comprises (A) 100 parts by weight of a glass fiber reinforced polycarbonate resin; and (B) about 0.1 to about 10 parts by weight of a polyolefin modified with at least one functional group selected from the group consisting of methacrylate groups, acrylate groups, modified ester groups, C6-C12 arylate groups, acrylonitrile groups, and combinations thereof.

Abstract: A resin pulley is provided in which, in particular, abrasion resistance in a dusty atmosphere and thermal shock resistance are superior and belt attacking property is suppressed. A resin composition including 35 to 55 mass % of a phenolic resin as a base resin, 1 mass % or more of an acrylonitrile butadiene rubber, 10 to 25 mass % of an inorganic fiber and 3 to 15 mass % of an inorganic powder, and further comprising a polyester acrylate, and a resin pulley formed with the use of the resin composition.

Abstract: A biocompatible coating for solid phase microextraction (SPME) of a small molecule from a biological matrix. The coating comprises SPME particles and a biocompatible polymer. The biocompatible polymer (e.g. polyacrylonitrile) reduces adsorption of proteins or macromolecules onto the SPME particles and allows the SPME particles to extract the small molecule from the matrix. A process for coating a flexible fiber with a biocompatible coating. The process comprises: coating the fiber with a suspension of SPME particles, the SPME particles being suspended in a solution of a biocompatible polymer and a solvent, the biocompatible polymer can comprise polyacrylonitrile (PAN); drying the coated fiber to remove the solvent; and curing the dried coated fiber at an elevated temperature.

Abstract: The invention relates to agglomerate particles which are constructed from agglomerated nanoscale primary particles and also to a method for incorporation of these particles in a polymer matrix and to the use of these agglomerate particles.

Abstract: A thermoplastic resin composition having good electromagnetic shielding properties and high stiffness comprising thermoplastic polymer, metal alloy having a melting point of between about 200° C. and 500° C.

Abstract: The present invention relates to a recording liquid comprising at least: a pigment (a); and a polymer (b) having one or more types of bond selected from the group consisting of amide bond, urethane bond and urea bond in the molecule, having a weight-average molecular weight of 5000 to 300000 and having an acid value of free acid of not less than 55 mgKOH/g and less than 150 mgKOH/g, the surface tension of said recording liquid being 25 to 54 dyne/cm.

Abstract: A process for producing a modified polymer which increases low heat buildup and reinforcing capability of a rubber composition and which has excellent abrasion resistance, mechanical characteristics, and processability; a modified polymer obtained by the process; and a rubber composition using the modified polymer are provided. The process comprises a step of carrying out a modification reaction on the active end of a conjugated diene polymer having a vinyl content of below 10%, a cis-1,4 bond content of 75% or higher, and an active end, using an alkoxysilane compound, and a step of carrying out a condensation reaction in the presence of a condensation accelerator comprising a compound of an element belonging to at least one of the groups 4A (excluding Ti), 2B, 3B, and 5B of the periodic table.

Abstract: Provided is an insulating layer in which an inorganic material is added to an organic polymer to thereby improve the insulating properties, an organic thin film transistor using the insulating layer, and a method of fabricating the organic thin film transistor. An insulating layer for an organic thin film transistor including a vinyl polymer and an inorganic material is provided. Here, a weight ratio of the vinyl polymer to the inorganic material may be in the range of 1:0.0001 to 1:0.5. Accordingly, it is possible to fabricate a thin film at low temperature and, further, to fabricate an insulating layer having a high-dielectric constant, not affecting other layers formed in the previous processes during the formation of the insulating layer.

Abstract: The rubber compositions described herein have been found to have an exceptionally long life as a spring-biased actuator diaphragm material that maintains its position compressed, e.g., bolted, between opposed flanges, while maintaining excellent compressibility, low temperature flexibility, hydrocarbon resistance, abrasion resistance and mechanical strength. The compositions include a copolymer rubber component; a plasticizer for the copolymer rubber; a vulcanizing agent for the copolymer rubber; a silica filler; and a coupling agent, such as a silane coupling agent, capable of coupling the silica filler to the copolymer rubber.

Abstract: Disclosed is a composition comprising or produced from nanoparticle-sized TiO2, an ethylene copolymer or ionomer of the ethylene copolymer, and optionally a second polymer. Also disclosed are films and other shaped articles produced therefrom. The composition, possessing a UV light barrier, can be used to protect the products that may be susceptible to UV such as foodstuffs.

Abstract: The present invention relates to polymer composites comprising at least one, optionally hydrogenated, nitrile rubber polymer having a Mooney viscosity (ML 1+4 @ 100° C.) below 30 at least one filler and optionally at least one cross-linking agent, a process for preparing said polymer composite wherein at least one, optionally hydrogenated, nitrile rubber polymer having a Mooney viscosity (ML 1+4 @ 100° C.) below 30, at least one filler and optionally at least one cross-linking agent are mixed and a process for the manufacture of a shaped article comprising the step of injection molding a polymer composite comprising at least one, optionally hydrogenated, nitrile rubber polymer having a Mooney viscosity (ML 1+4 @ 100° C.) below 30, at least one filler and at least one cross-linking agent.

Abstract: An aqueous elastomer coating composition and objects coated with this elastomer coating composition are described.

Abstract: The present invention relates to polymer composites containing at least one, optionally hydrogenated, nitrile rubber polymer having a Mooney viscosity (ML 1+4 @ 100° C.) in the range of from 50–30 at least one filler and optionally at least one cross-linking agent, a process for preparing said polymer composite wherein at least one, optionally hydrogenated, nitrile rubber polymer having a Mooney viscosity (ML 1+4 @ 100° C.) in the range of from 50–30, at least one filler and optionally at least one cross-linking agent are mixed and a process for the manufacture of a shaped article including the step of injection molding a polymer composite containing at least one, optionally hydrogenated, nitrile rubber polymer having a Mooney viscosity (ML 1+4 @ 100° C.) in the range of from 50-30, at least one filler and at least one cross-linking agent.

Abstract: A method for modifying polyolefin-clay nanocomposites is disclosed. The method comprises shearing a melt of solution-prepared nanocomposites at an effective shear rate. The modified nanocomposite shows significantly decreased complex melt viscosity, storage modulus, and loss modulus.

Abstract: A method of dispersing an insoluble material in an aqueous solution comprising the following steps: (i) providing a formulation comprising at least one insoluble material and at least one dispersant comprising a water soluble agriculturally acceptable derivative of an alternating copolymer or an agriculturally acceptable salt thereof wherein said alternating copolymer comprises at least one residue of a first comonomer and at least one residue of a second comonomer, wherein said first comonomer comprises ?,?-unsaturated oxyacids or anhydrides and said second comonomer comprises olefinic compounds containing one or more polymerizable double bonds; and (ii) dispersing said formulation in an aqueous medium.

Abstract: The invention is the manipulation of the zinc oxide content and sulfur content of nitrile butadiene rubbers and selected vulcanization conditions that can be achieved economically with common production facilities. The manipulation of these components affects the relaxation property of gloves formed by this material. Produced are gloves that have a relaxation property, higher than 50%, and a low modulus (approximately 3 Mpa). The glove maintains decent ultimate tensile strength (>20 Mpa) and elongation (>500%). The glove is produced by a vulcanization process, which lasts from 5 to 60 minutes at temperatures ranging from 300° F. to 400° F. The tensile strength and elongation are well above the ASTM requirements for medical gloves. The current ASTM requirements are ASTM D412-92. Thanks to sufficient vulcanization, the films produced provide satisfactory protection from viral penetration. The tearing strength is also better because of the lower modulus.

Abstract: A novel agricultural formulation includes at least one finely divided solid water-insoluble material and at least one novel dispersant containing a polymer synthesized from first and second comonomers. The first comonomer is an ?,?-unsaturated oxyacid or anhydride, and the second comonomer is an olefin having at least one polymerizable double bond. Also disclosed is a method for dispersing a finely divided solid insoluble material, in particular, an active water-insoluble agrochemical principal, in an aqueous solution; a method for treating a substrate with such a material or principal; and a method of making an agrochemical formulation, where the methods are based on application of the novel dispersant to the preparation of aqueous dispersions of the solid material and agrochemical principal.

Abstract: A hydrogenated nitrile rubber composition, which comprises 100 parts by weight of hydrogenated nitrile rubber with a bound acrylonitrile content of not less than 30%, a polymer Mooney viscosity ML1+4(100° C.)(according to JIS K6395) of not more than 80 (median value) and an iodine number of not more than 28 (median value), and 65 to 200 parts by weight of carbon fibers is provided as a hydrogenated nitrile rubber composition containing carbon fibers as filled at a high density, which can overcome inconveniences as to kneadability and moldability and improve the wear resistance, and thus can be used as a suitable molding material for sealing members.

Abstract: An uncured epoxy adhesive comprising a resin component, a hardener component, and a microencapsulated accelerator component. The microencapsulated accelerator component comprises an infrared absorber, an accelerator and a wall that covers substantially the entire surface of the accelerator. The epoxy adhesive is cured by exposing it to infrared energy. The infrared energy is absorbed by the infrared absorber which disintegrates the wall and allows the accelerator to come into contact with the other adhesive components and initiate the curing polymerization reaction.

Abstract: The invention relates to comb polymers and macromonomers based on acrylates prepared by the ATRP (Atom Transfer Radical Polymerization) method. These polymers have an improved capability of dispersing pigments in the given solvent. The invention also relates to compositions comprising the comb polymers and macromonomers dispersible inorganic or organic pigment particles. The compositions are used by applying them to any suitable substrate, for example to metal, wood plastic or ceramic materials.

Abstract: Active water compatible actinic radiation curable printing ink or coating compositions comprised of maleimide derivatives, water compatible resins and water, which are capable of curing at a practical intensity and energy level and a method for curing same.

Abstract: A novel agricultural formulation includes at least one finely solid water-insoluble material and at least one novel dispersant containing a polymer synthesized from first and second comonomers. The first comonomer is an ?,?-unsaturated oxyacid or anhydride, and the second comonomer is an olefin having at least one polymerizable double bond. Also disclosed is a method for dispersing a finely divided solid insoluble material, in particular, an active water-insoluble agrochemical principal, in an aqueous solution; a method for treating a substrate with such a material or principal; and a method of making an agrochemical formulation, where the methods are based on application of the novel dispersant to the preparation of aqueous dispersions of the solid material and agrochemical principal.

Abstract: This invention relates to a jointing compound of an acrylate/acrylonitrile copolymer containing 2 to 8 carbon atoms in the alcohol component as binder and fatty compounds as plasticizer and also fillers and auxiliaries. Epoxystearic acid methyl ester in particular may be used as the fatty compound while a butyl acrylate/acrylonitrile copolymer in particular may be used as the acrylate/acrylonitrile copolymer. The combination of the two substances results in jointing compounds characterized by a dramatic improvement in elasticity (resilience). Accordingly, they are particularly suitable for substrates with different coefficients of thermal expansion.

Abstract: The present invention relates to preparation of fluorinated core-shell particles with water and oil repellency, and more particularly, to preparation of emulsion-type coating material with good water and oil repellency using only small amount of expensive fluorinated monomers, which comprise a shell wherein a large amount of hydrophobic fluorinated monomers are included and a core wherein no fluorinated monomers are included.

Abstract: The invention is directed to a new formulation for making a carboxylated polyacrylonitrile butadiene (usually referred to as nitrile in the glove industry) glove. The new formulation contains no accelerators commonly used in sulfur vulcanization. A sulfur free (including organic sulfur donors) crosslinking system is utilized. The invention provides formulations to make compounds and methods to make such gloves. The new formulations and procedures could be easily realized economically under common glove production lines. Depending on the desired applications, both powdered and powder free gloves are produced in the same formula.

Abstract: Active water compatible energy curable compositions comprised of maleimide derivatives, water compatible resins and water which are capable of curing at a practical intensity and energy level and a method for curing same.

Abstract: An objective of the invention is to provide a conjugated diene-based rubber having a specific composition and an oil extended rubber using the same, as well as a rubber composition capable of being converted into a vulcanized rubber which has a low rolling resistance, an excellent wearing resistance and the like, and is useful for a tire or the like. A conjugated diene-based rubber in the invention has repeating units consisting of 1 to 30% by mass of an olefinically unsaturated nitrile monomer unit such as acrylonitrile, 10 to 50% by mass of an aromatic vinyl monomer unit such as styrene, 19.9 to 88.9% by mass of a conjugated diene monomer unit such as 1,3-butadiene and 0.1 to 10% by mass of a monomer unit having one polymerizable unsaturated group and at least one functional group selected from the group consisting of an amino group, a hydroxyl group, an epoxy group, a carboxyl group and an alkoxysilyl group, and has a specific glass transition point and a Mooney viscosity [ML1+4(100° C.

Abstract: The present invention relates to a process for hydrogenating ethylenically unsaturated double bonds in polymers P by reacting an aqueous dispersion of at least one polymer P with hydrogen in the presence of at least one hydrogenation catalyst comprising at least one transition metal selected from rhodium and/or ruthenium and at least one nonionic phosphorus compound capable of forming a coordinative compound with the transition metal, which comprises incorporating the hydrogenation catalyst into the aqueous dispersion of the polymer P without adding a solvent. The present invention also relates to the aqueous dispersions of the hydrogenated polymers P obtainable by this process and to coating compositions comprising such dispersions.

Abstract: A pigment dispersion comprising pigment, an aqueous carrier selected from water and a mixture of water and at least one organic solvent, and a pigment dispersant is described. The pigment dispersant is prepared by controlled radical polymerization, e.g.

Abstract: Mixture of at least one filler and organosilicon compounds of the general formula Y—Sx-Z, wherein the filler is surface-treated, hydrophobic, precipitated silica, are prepared by homogeneously applying an organosilicon compound from a nozzle to the surface-treated, hydrophobic, precipitated silica in a mixing unit at a temperature of less than 50° C. The mixture can be used in rubber mixtures.

Abstract: Ammonia-free polymer dispersions containing at least one copolymer which contains, as polymerized monomers, a) from 40 to 80% by weight of at least one ester of acrylic acid with C2-C12-alkanols, b) from 10 to 40% by weight of at least one vinylaromatic monomer and/or at least one ester of methacrylic acid with C1-C4-alkanols, c) from 2 to 15% by weight of at least one monoester of a C2-C10-alkanediol with acrylic acid or methacrylic acid, d) not more than 1% by weight of ethylenically unsaturated monomers which have at least one acid group, or salts thereof, e) less than 5% by weight of &agr;,&bgr;-ethylenically unsaturated nitrites and f) less than 1% by weight of amides of &agr;,&bgr;-ethylenically unsaturated mono- and dicarboxylic acids, and the polymer powders or polymer granules obtainable from the polymer dispersion, are used as additives for building materials based on hydraulic binders.

Abstract: A process for producing a superabsorbent polymer is described. The process that entails a continuous hydrolysis of an aqueous emulsion of crosslinked or uncrosslinked polyacrylonitrile in the form of fine particles is carried out in a cascade of stirred tanks. The reaction with alkali-hydroxide solution an aqueous-alcoholic medium at 60 to 100° C. yields polymers that are suitable for the preparation of hygiene products, water-storing materials in agriculture, and sheathing of electrical cables.

Abstract: The present invention provides a composition for forming a removable coating for an optical substrate. In this form, the composition is an aquesous emulsion having one or more substantially non-polar polymers.

Abstract: An objective of the invention is to provide a conjugated diene-based rubber having a specific composition and a method of producing the same, an oil extended rubber using the same, as well as a rubber composition capable of being converted into a vulcanized rubber which has a low rolling resistance, an excellent wearing resistance and the like, and is useful, for example, as a tire or the like. A conjugated diene-based rubber in the invention has a glass transition point of −60 to 0° C., an olefinically unsaturated nitrile monomer unit randomly contains in its molecular chain, its repeating units consists of 9 to 30% by mass of an olefinically unsaturated nitrile monomer unit such as acrylonitrile, 10 to 50% by mass of an aromatic vinyl monomer unit such as styrene and 20 to 81% by mass of a conjugated diene monomer unit such as 1,3-butadiene, and its Mooney viscosity [ML1+4(100° C.)] is 20 to 200.

Abstract: A rubber composition having improved properties containing a starting rubber (e.g., diene rubber) and a polysiloxane having the following alkoxysilyl group (I) and/or acyloxysilyl group (II) and having an average degree of polymerization of 3 to 10,000: ≡Si—OR1  (I) ≡Si—OCOR2  (II) wherein, R1 is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 18 carbon atoms or an organic group containing an ether bond and R2 is hydrogen or a hydrocarbon group having 1 to 21 carbon atoms.

Abstract: An objective of the present invention is to provide an unsaturated nitrile-conjugated diene-typed rubber capable of giving a vulcanized rubber which exhibits is well-balanced in terms of the mechanical strength, the oil resistance and the like, as well as a process for the production of the same, and a rubber composition which is containing such rubber and exhibits an excellent processability as well as a process for the production of the same. The unsaturated nitrile-conjugated diene-typed rubber in the invention is produced by polymerizing using certain amounts of an olefinically unsaturated nitrile monomer such as acrylonitrile and a conjugated diene monomer such as butadiene at first, and continuing by supplying a remainder of the monomers at a certain ratio continuously or stepwise to proceed the polymerization.

Abstract: A highly saturated nitrile group-containing copolymer rubber having a Mooney viscosity lowered by 15 points or more by applying a high shearing force thereto in the presence of an aging inhibitor, which has a Mooney viscosity of 5-35 and a weight average molecular weight/number average molecular weight ratio of 3-5, and exhibits an increase in Mooney viscosity of 10 points or fewer while the rubber is allowed to stand in the air at room temperature for 30 days. The viscosity of the copolymer rubber changes only to a minor extent with the lapse of time, and the copolymer rubber has excellent processability and storage stability. The copolymer rubber can be used as a heat-resistant rubber composition comprising the copolymer rubber and other heat-resistant rubber. The copolymer rubber can be used as a composite thereof with a fiber, which has good mechanical strength.

Abstract: A pigment dispersion that includes a pigment, an aqueous carrier, and a pigment dispersant. The pigment dispersant is prepared by atom transfer radical polymerization initiated and has the polymer chain structure: &phgr;—(G)p—(E)a—T where G is a residue of at least One ethylenically unsaturated monomer; E is a hydrophilic residue of at least one ethylenically unsaturated monomer; &phgr; is a hydrophobic residue of or derived from an initiator; T is or is derived from a radically transferable group from the initiator, p and s represent average numbers of residues occurring in a block of residues; p and s are each individually selected such that said pigment dispersant has a number average molecular weight of at least 250.