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    • 专利摘要:
    Methods of preparing dispersions of small particles in the precursor polymers provide a mixture of surfactant and particulate material in a non-aqueous solvent, form a dispersion of particulate material in a non-aqueous solvent, and Blending the dispersion and heating the blend of precursor material and particulate dispersion to a temperature sufficient to evaporate the non-aqueous solvent. Surfactants are soluble in non-aqueous solvents and stabilize particulate matter from flocculation. The non-aqueous solvent swells the precursor polymer near its boiling point. The range of non-aqueous solvents is higher than the temperature at which the precursor polymer can be mixed and lower than the temperature at which the precursor polymer is polymerized or degraded. In certain embodiments, the particulate material is inorganic. For example, inorganic materials are ferroelectric materials such as barium titanate and lead titanate. In another embodiment, the microparticles are ferromagnetic materials such as magnetite, barium ferrite.
    公开号:KR20000069322A
    申请号:KR1019997005010
    申请日:1997-12-05
    公开日:2000-11-25
    发明作者:레오니드 안토니 터케비치；데이빗 루이스 마이어스
    申请人:로날드 디. 맥크레이；킴벌리-클라크 월드와이드, 인크.；
    IPC主号:
    专利说明:

    Method for Preparing Small Particle Dispersion {Method of Preparing Small Particle Dispersions}
    Cross Reference to Related Application
    The methods claimed and described in this application are described in, but not claimed in, co-pending and commonly assigned US patent application Ser. No. 08 / 762,213.
    Background of the Invention
    The present invention relates to small particle dispersions in a liquid medium.
    It is often desirable or necessary to prepare dispersions of solid or particulate matter in liquids or other solid media. Adding pigments to oily and aqueous paints (or latexes) is a good example of a dispersion of solid pigment (s) in a flow carrier that forms a continuous liquid phase. Likewise, pigments and organic dyes are added to the solid material to impart various color properties to the colorless material. Techniques for preparing dispersions of this type are well known. Typically, the aqueous particle dispersion is blended with the continuous phase material through a process called flushing. The particles are incorporated into the continuous phase and the water is removed by decantation or heating under vacuum.
    The preparation of small particle dispersions is complicated by the tendency of the particles to aggregate into macroscopic large aggregates. Large agglomerates are undesirable because they cause non-uniform coloring in the case of pigments or non-uniform physical properties in the case of other additives. In aqueous dispersions of small particles, surfactants are used to avoid the problems mentioned above by "stabilizing" the particles so that they do not reaggregate.
    In the case of non-aqueous media, the role of surfactants is less known. Particles dispersed in the non-aqueous medium exhibit the same aggregation problems as they do in the aqueous medium, but for non-aqueous media the behavior of surfactant-like molecules appears very different from that in the aqueous medium. If the agglomeration of small particles in non-aqueous media can be overcome, the non-aqueous dispersion will have significant advantages in the production of other solid-liquid, solid-solid and solid-semi-solid dispersions.
    While methods for preparing non-aqueous or oil-based particle dispersions are well known, their use as intermediates in the production of other types of particle dispersions is not well known. For example, the above-mentioned U.S. Patent Application No. 08 / 762,213, which is incorporated herein in its entirety, describes the preparation of fibers containing ferroelectric particles. Preparation of the fibers first requires preparing a dispersion of the particles in a non-aqueous solvent and dispersing the particles in an organic wax. The present invention provides an improvement in the preparation of wax dispersions.
    Summary of the Invention
    The present invention relates to small particle dispersions in liquid or polymer media. In either case, the liquid or polymer medium forms a continuous phase and the particles are in a discontinuous phase. The present invention provides a mixture of particulate matter and a surfactant in a nonaqueous solvent, forms a particulate dispersion in a nonaqueous solvent, blends the resulting particulate dispersion in a nonaqueous solvent with a precursor polymer material, The difficulties and problems discussed above are solved by providing a method for preparing small particle dispersions in precursor polymers, which consists of heating the mixture to a temperature sufficient to evaporate the non-aqueous solvent. Surfactants are soluble in non-aqueous solvents and stabilize fine particles from aggregation. The non-aqueous solvent swells the precursor polymer near its boiling point. As a result, the boiling point of the non-aqueous solvent is higher than the temperature at which the precursor polymer can be mixed and lower than the temperature at which the precursor polymer is polymerized or degraded.
    In certain embodiments, the microparticles are inorganic. For example, the inorganic material may be a metal oxide.
    As used herein, the term "precursor polymer" includes low molecular weight organic polymer waxes (organic waxes), oligomers (or macromers) and monomers for illustrative purposes only.
    "Organic wax" means an organic polymeric material that is liquid, semisolid or solid at ambient temperature, ie, 20-25 ° C. For illustrative purposes only, typical liquids are oligomeric forms of low weight average molecular weights (M w ) of polyethylene, polypropylene, polyisobutylene. Typical examples of semisolids are polyisobutylene (M w = 100,000) and atactic polypropylene. Examples of typical solids are polyethylene (M w = 1,000-4,000), polypropylene (M w = 1,000-4,000) and various carboxylate, amide and alcohol-based waxes.
    As used herein, the term "ferroelectric material" means a crystalline material having spontaneous polarization that can be redirected by application of an electric field. The term includes all phases or combinations thereof that exhibit spontaneous polarization in which the magnitude and orientation of the polarity can be varied as a function of temperature and externally applied electric field. The term also encompasses mixtures of a single ferroelectric material and two or more ferroelectric materials of the same or different classes. Ferroelectric materials also include "doped" ferroelectric materials, ie solid solutions of such substituents in host ferroelectric materials or ferroelectric materials containing small amounts of elemental substituents.
    The structure of the crystalline material is typically classified into 32 symmetric structural groups. 21 of these are nonsymmetrical. That is, they do not have a center of symmetry. Twenty of the nonsymmetric symmetry groups are piezoelectric, and only ten of these twenty are called pyroelectrics. Pyroelectric materials are unique in that they have spontaneous electrical polarization directly attributable to permanent dipoles present at the unit cell level in the individual crystals. The arrangement of dipoles along the crystal axis of the material results in net spontaneous polarization in the material. Pyroelectric materials are also referred to as polar solids. As the name implies, "superelectricity" means that the magnitude and direction of the spontaneous polarity changes with temperature. Ferroelectric materials are a subgroup of pyroelectric materials that spontaneously polarize. The magnitude and direction of spontaneous polarization in ferroelectric materials reacts to both temperature and externally applied electric field.
    All ferroelectric materials exhibit a "Curie point" or "Curie temperature" which is the critical temperature at which spontaneous polarization disappears at higher temperatures. Curie temperatures are often referred to herein as "T c ".
    Ferroelectric materials include perovskite, tungsten bronze, layered bismuth oxide, pyrochlor, alum, Rochelle salt, dihydrogen phosphate, dihydrogen arsenate, guanidine aluminum sulfate hexahydrate, triglycine sulfate, cholemanite and Thiourea, and the like. More useful materials of this kind are discussed in detail below.
    Perovskite
    Perovskite is a mixed metal oxide having a stoichiometry of ABO 3 type. Perovskite occupies the central octahedral B position with highly charged small cations such as titanium (Ti), tin (Sn), zirconium (Zr), niobium (Nb), tantalum (Ta) and tungsten (W). Degraded large cations such as Na, potassium (K), rubidium (Rb), calcium (Ca), strontium (Sr), barium (Ba), and lead (Pb) are between the oxygen octahedron in the larger 12 coordination A position. It has a very simple three-dimensional structure consisting of oxygen octahedron filling the vertex, filling the gap of. The ferroelectricity associated with these materials is due to the distortion of the lattice that occurs below the Curie temperature, resulting in the formation of very large dipoles in the crystal.
    Perovskite is unique in that it forms a variety of solid solutions ranging from simple two- or three-membered solid solutions to very complex multicomponent solid solutions. Some examples are given for illustrative purposes only without limitation, BaSrTiO 3 , KBaTiO 3 , Pb (Co 0.25 Mn 0.25 W 0.5 ) O 3 , and barium titanate doped with niobium oxide, antimony oxide, lanthanum oxide And lead titanate. The wide solid solution formation ability of perovskite compounds allows those skilled in the art to systematically change the electrical properties of materials by forming solid solutions or adding dopant phases. For example, the Curie temperature of barium titanate (BaTiO 3 ) can be systematically increased from 130 ° C. to 490 ° C. by replacing barium ions with lead ions, and reaches a T c upper limit when the lead ion substitution rate is 100%. Likewise, it is known that the T c of barium titanate slowly decreases by replacing barium ions with strontium ions.
    Perovskite Related Octahedral Structure
    This material has a structure similar to perovskite, except that oxygen octahedrons share edges rather than share vertices. Of these kinds, only two kinds of lithium niobate (LiNbO 3 ) and lithium tantalate (LiTaO 3 ) are important. For convenience these materials are included in "perovskite".
    Tungsten bronze
    Tungsten Bronze is a regular diet (0 <n ≦ l, M is a monovalent metal cation, most typically Na) and is a nonstoichiometric material. Ferroelectric tungsten bronze is typically n ≦ 0.3. Materials of this kind include lead metanibate (PbNb 2 O 6 ) and lead metatantalate (PbTa 2 O 6 ).
    Layered bismuth oxide material
    It is a complex layered structural material in which a perovskite layer is inserted into a bismuth oxide layer. Typical bismuth oxide layered compound is lead bismuth niobate (PbBiNb 2 O 9 ).
    Pirochlor
    Pyrochlor is a vertex-covalent oxygen octahedral structure similar to perovskite. However, these classes of compounds are more limited in cation substitution. Typical pyrochlores are cadmium niobate and tantalate, lead niobate and lead tantalate. These materials have Curie temperatures of less than 200 ° K (73 ° C) and may be of limited use in some applications.
    The term "ferromagnetic material" means a crystalline material having residual magnetization induced by a magnetic field. The term includes any phase or combination of phases whose magnitude can be varied as a function of temperature and external magnetic field. Ferromagnetic materials also include single, binary, tertiary or more mixtures of the same or different types of ferromagnetic materials. Furthermore, it includes "doped" ferromagnetic materials.
    The term "broken" and its modifications mean a reduction in the size of the particles of the material to be dispersed. The terms "particle" and "aggregated particle" refer to particles of material that have not been treated to reduce particle size. "Destroyed particles" means "particles" or "aggregated particles" that have been treated or destroyed to reduce particle size.
    In general, particles of any size may be used in the present invention as long as the size permits the preparation of dispersions useful for the intended use. For example, the longest dimension of the particles may range from about 10 nanometers to about 10 micrometers. If necessary, the particles can be destroyed.
    Destruction of the particles can be carried out by any method known to those skilled in the art. For example, the particles can be destroyed by treatment in ball mills, wear mills or pin mills. Processing conditions will vary depending on the design and operating conditions of the ball mill used, but those skilled in the art will readily be able to determine appropriate conditions. Destruction is typically carried out in the presence of a non-aqueous solvent and a surfactant, the surfactant being soluble in the solvent and stabilizing the broken particles from aggregation.
    In general, the process of the present invention employs non-aqueous solvent dispersions of surfactants and propolymer materials that stabilize particles and particles against aggregation. As already mentioned, non-aqueous solvents and surfactants are used to form solvent dispersions of the particles. Solvent dispersions may be prepared by various particle-dispersion methods, such as ball milling, small media milling, or high shear / wear milling, to name just a few.
    The non-aqueous solvent is chosen to have a boiling point higher than the softening point of the precursor polymer that is solid at ambient temperature, or a temperature higher than necessary to reduce the viscosity of the liquid polymerization precursor to the point where it can mix. In addition, the boiling point of the solvent should be below the decomposition temperature of the precursor polymer and / or below the temperature at which polymerization can be initiated.
    In general, any liquid that is a solvent of the surfactant can be used. The surfactant stabilizes the crushed particles from aggregation. Suitable liquids include aliphatic hydrocarbons such as hexane, heptane, octane and decane; Aromatic hydrocarbons such as xylene, toluene and cumin; Aliphatic alcohols such as 2-propanol, 1-butanol, 1-hexanol and benzyl alcohol; Aliphatic ketones such as methyl ethyl ketone; Halogenated hydrocarbons such as dichloromethane, chloroform, carbon tetrachloride and chlorobenzene; And polar solvents such as water, tetrahydrofuran and N, N-dimethylpyrrolidinone.
    The liquid is preferably an aliphatic alcohol having about 3-10 carbon atoms. For example, aliphatic alcohols include normal alcohols having about 4-10 carbon atoms, such as 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, and 1-nonanol. . Another example is an aliphatic alcohol containing a branched alkyl group. 2-propanol, 2-butanol, 2-methyl-2-propanol, 2-pentanol, 3-pentanol, 2-methylbutanol, 3-methylbutanol, 2-hexanol, 3-hexanol, 3,3- Dimethylbutanol, 3-heptanol, 4-heptanol, 2-ethyl-1-propanol, 4-octanol, 3,3-dimethyl-1-hexanol, 5-nonanol, 6,6-dimethyl-2- Examples are heptanol, 5-ethyl-3-heptanol, 2-decanol, and 3,4,7-trimethyl-1-heptanol.
    Forms of surfactants that may be used in the process of the present invention include cationic, anionic, nonionic and zwitterionic surfactants. In some instances, it may be desirable to mix and use two or more surfactants to stabilize the broken ferroelectric particles. Examples of cationic surfactants include aliphatic and aromatic primary, secondary, tertiary amines; Amine oxides, amide bonded amines; And quaternary ammonium salts. Examples of anionic surfactants include carboxylic acids and salts; Sulfonic acid and salts; Fatty acids such as oleic acid; Lignosulfonate; Alkyl benzene sulfonates; Alkyl aryl sulfonates; Petroleum sulfonic acid salts; Sulfonates with ester, ether, or amide bonds; Sulfuric acid esters and salts; Sulfate alcohols; Sulfate ethoxylated alcohols; Sulfate ethoxylated alkylphenols; Sulfate acid; Sulfate amides; Sulfate esters; Sulfated natural fats and oils; Ethoxylated alkylphosphate esters; Phosphoric acid, polyphosphoric acid esters and salts; Phosphated alcohols; Phosphated phenols; Phosphated alkoxylated alcohols; Phosphated alkoxylated phenols; And salts of each kind of phosphated anionic surfactant. Examples of nonionic surfactants include ethoxylated alcohols; Ethoxylated alkylphenols; Ethoxylated carboxylic acid esters; Glycerol esters; Polyethylene glycol esters; Sorbitol esters; Ethoxylated natural fats and oils; Ethylene and diethylene glycol esters; Propanediol esters; And ethoxylated carboxylic acid amides.
    In general, surfactants are used in an amount sufficient to stabilize the broken ferroelectric material from aggregation. For example, the surfactant is used in the range of about 0.01-10% by weight based on the total amount of ferroelectric material to be broken down and stabilized from aggregation. The surfactant is preferably used in the range of about 0.01-1% by weight.
    The mixture of nonaqueous solvent and propolymer consists of one or two phases if the temperature of the mixture is at or above the boiling point of the nonaqueous solvent. In the case of a two-phase system, the composition of the phase is determined by the relative miscibility of the constituents. Near the boiling point, the nonaqueous solvent acts as a solvent or nonsolvent for the precursor polymer. In either case, the non-aqueous solvent swells the precursor polymer near its boiling point.
    In one embodiment, the non-aqueous solvent / particle dispersion (or solvent dispersion) is mixed with the precursor polymer while heating to evaporate off the solvent to disperse the particles in the precursor polymer. When the solvent dispersion-precursor polymer mixture is a single phase at the boiling point of the solvent, small particles remain in the medium where the precursor gradually increases by evaporating the volatile solvent. When the solvent is completely removed, a particle-precursor polymer dispersion is formed. If the solvent dispersion-precursor polymer mixture consists of two phases, the particles are partitioned between the two phases when the volatile solvent is evaporated off. Upon complete removal of the non-aqueous solvent, a dispersion of the particle-precursor polymer is formed.
    The present invention is explained in more detail through the following examples. However, the examples should not be regarded as limiting the gist or scope of the present invention in any sense.
    Example 1
    Preparation of Solvent Dispersion
    Barium titanate (BaTiO 3 ) is TICON 5016 available from Tam Ceramiscs, Inc. Niagara Falls, New York. Solvent dispersions were prepared using a large stainless steel mixing tank (about 130 gallons or 492 liters) equipped with a hydraulic stirrer. The dispersion was processed through a high speed stainless steel pin / wear mill using an electric motor of 1750 rpm, 50 horsepower. Mixing tanks and pin / wear mills were made to orderridge stand-ups from Standridge Color Corporation, Social Circle, Georgia. Half of the bottom of the mixing tank was in the form of a funnel. The mixing tank was connected to a hydraulic pump, which was connected to the pin / wear mill through a 2.5 inch (about 10 cm) diameter soluble hose. The effluent from the mill was recycled to the top of the mixing tank. The hydraulic pump discharged 0.25 gallons (about 0.95 liters) once and operated at a flow rate of 8-10 gallons per minute (about 0.5-0.6 liters per second).
    The mixing tank was filled with 190 pounds (86.4 kg) of industrial 1-butanol. Rhodamine 7.2 pounds (3.27 kg) of PN430 (Rhone-Poulenc) was added with vigorous stirring. Barium titanate was added to the mixing tank until 55 pounds (about 25 kg) totaled 770 pounds (about 350 kg). The slurry was fed to a high speed pin / wear mill and recycled to the mixing tank for approximately 30 minutes. The resulting 1-butanol dispersion was single in composition and contained 80% by weight of barium titanate.
    Formation of Polyethylene Wax Dispersions
    An 80 wt% barium titanate / 1-butanol dispersion was added directly to the molten low molecular weight polyethylene (PE) wax (A-C 16 from Allied Signal). It should be noted that in the previous example 50 wt% barium titanate aqueous dispersion was added to the molten PE wax through a process commonly known in the art as flushing. In this example, the stabilized colloidal barium titanate particles were partitioned into 1-butanol-rich phase and PE wax-rich phase and 1-butanol was evaporated off. This process differs from water / wax flushing in that 1-butanol boils at temperatures above the melting point of A-C 16 PE wax. The wax was melted in a 150 gallon (approximately 568 liter) steam-heated batt that slowly mixed the mixture using a rotating blade. Steam was supplied to 50 psig of batt at a temperature corresponding to about 297 ° F. (about 147 ° C.).
    In this example, 1-butanol / barium titanate / rhodamine 969.20 pounds (440.55 kg) of PN-430 dispersion was mixed with 190.8 pounds (86.73 kg) of AC 16 PE wax. The molten wax and 1-butanol dispersion were continuously mixed until no alcohol vapor was detected in the mixture. At this point, BaTiO 3 / rhodamine The Pn-430 / AC 16 PE wax dispersion was cooled to room temperature along the dish. The solidified wax composite was cooled to dry ice temperature and ground to a coarse powder for dry mixing with polypropylene.
    Polypropylene Kneading
    BaTiO3 / Rhodamine Montel Profax PN-430 / AC 16 PE Wax Composite 832 lbs. Dry mixed with 2,496 pounds (approximately 1339 kg) of PF-015 polypropylene (PP). The dry mixture was melt mixed using a single screw kneading extruder to obtain a mixture comprising 20 wt% barium titanate. Thin films prepared from the mixtures were examined by light microscopy and showed that the particles were well dispersed in a continuous polypropylene matrix.
    Example 2
    600 pounds (273 kg) of the 20 wt% concentrate prepared in Example 1 was added to Montel Profax. PF-015 polypropylene was mixed with 1800 pounds (approximately 818 kg). This dry mixture was melt mixed using a single screw kneading extruder to obtain a 5 wt% barium titanate / polypropylene composite.
    Nonwoven Structure Formation
    The nonwoven structure was made essentially on a 100 inch (about 2.5 meter) meltblown line as described in US Pat. The 100 inch wide web was cut into five 20 inch (about 51 cm) pieces. Meltblowing conditions were kept constant for all materials. All structures had a nominal basis weight of 0.6 osy (about 20 gsm). New Montel Profax 20% Barium Titanate / Polypropylene Composite Dry mixing with PF-015 at a ratio of 1-15 parts yielded a meltblown fabric comprising about 1% by weight barium titanate. The 5 wt% barium titanate / polypropylene composite was treated without further dilution. Finally, the new Montel Profax PF-015 polypropylene was melt spun to serve as a control standard. All meltblown nonwoven webs were treated with on-line electrets under the same conditions. Electret treatment was performed as taught in US Pat. No. 5,401,446 (Tsai et al.).
    result
    Air filtration measurement
    The air filtration efficiency of the meltblowing nonwoven web was evaluated using a Model 8110 Automatic Filter Tester (AFT) from TSI Inc. (Saint Paul, Minnesota). Model 8110 AFT measured the pressure drop and particle filtration characteristics for the air filtration media. AFT produced sub-micron sodium chloride aerosols, which are compressed with aerosols to measure filter performance using compressed air nebulizers. The characteristic size of the particles used for this measurement is 0.1 micrometers. Typical air flow rates were between 31 liters and 33 liters per minute. AFT experiments were performed on samples of about 140 cm 2 area. The efficiency or performance of the filter medium is expressed as the percentage of sodium chloride particles that pass through the filter. Permeation is defined as the transmission of particles through a filter medium. The transmitted particles are detected downstream of the filter. Permeation percentage (% P) reflects the ratio of downstream particle counts to the particle counts upstream. Light scattering was used to count and detect sodium chloride particles.
    Meltblown material samples were taken from ten cross deck positions of the nonwoven web (eg two per 20 inch slit). The samples were cut into flat plates approximately 8 inches square. At least 20 samples were evaluated for pressure drop (Δp in mm H 2 O) and percent particle permeation (% P). Tables 1 to 3 summarize the pressure drop and particle permeation data of the control formulation (Mntel Profax PF-015) and the formulation containing barium titanate.
    Air Filtration Results for Polypropylene Control Standard Webs Cd a Pressure drop b σ (△ p) c % P d σ (% P) e5 (13)2.070.0717.350.64 15 (38)1.900.0720.831.31 25 (64)2.420.0813.421.12 35 (89)2.640.0811.771.08 45 (114)2.720.0811.270.85 55 (140)2.750.0912.591.23 65 (165)2.640.0913.151.09 75 (190)2.470.1013.771.03 85 (216)2.240.0517.291.19 95 (241)2.320.0614.091.06a cross deck position, inches (cm)b mm H 2 Oc standard deviation of the pressure drop measurementd transmission percentagee standard deviation of the transmission percentage measurement
    Air Filtration Results for Polypropylene Webs Containing 1 wt.% BaTiO 3 CD a Pressure drop b σ (△ p) c % P d σ (% p) e5 (13)2.260.087.850.58 15 (38)1.920.0610.980.87 25 (64)2.250.078.461.06 35 (89)2.570.095.990.41 45 (114)2.730.095.680.63 55 (140)2.790.114.860.42 65 (165)2.490.086.880.62 75 (190)2.470.097.080.58 85 (216)2.210.079.881.12 95 (241)2.180.069.591.01a cross deck position, inches (cm)b mm H 2 Oc standard deviation of the pressure drop measurementd transmission percentagee standard deviation of the transmission percentage measurement
    Air Filtration Results for Polypropylene Webs Containing 5 wt.% BaTiO 3 CD a Pressure drop b σ (△ p) c % P d σ (% p) e5131.810.067.050.41 15381.670.058.850.63 25642.30.075.830.44 35892.530.074.970.63 451142.720.134.080.33 551402.590.113.860.39 651652.340.084.720.52 751902.350.084.720.34 852162.120.16.160.55 952412.060.056.140.86a cross deck position, inches (cm)b mm H 2 Oc standard deviation of the pressure drop measurementd transmission percentagee standard deviation of the transmission percentage measurement
    The pressure drop (Δp) and particle permeation percent (% P) data shown in Tables 1-3 clarify the superior filtration performance of meltblown webs made from barium titanate / PP composites. All webs examined were characterized by cross deck profile in pressure drop and permeation data. The shape of the profile is independent of the material. The pressure drop measured along the web was the same for each of the three materials described. This suggests that fiber and web formation is independent of spinning materials (eg polypropylene to barium titanate / PP composites). In contrast, the particle permeation percentages were significantly lower compared to the control standard polypropylene in both the 1 wt% and 5 wt% BaTiO 3 formulations. Thus, for a given pressure drop across the web, the barium titanate / PP composite showed better filter performance than the control standard polypropylene.
    Example 3
    The procedure of Example 1 was repeated except that barium titanate was replaced with lead titanate and the particles were destroyed using a ball mill as described below.
    In a typical batch mode, approximately 1 kg of lead titanate was vigorously stirred with 2.6 L of 1-butanol and 4-5 ml of surfactant. The resulting slurry was poured into 6.2 L of Roalox ceramic mill ego (U. S. Stoneware, East Palestine, Ohio) filled with 21 pounds (about 5.4 kg) of zirconia grinding media (U. S. Stoneware). Ego metaphor. s. Using Stoneware (Model 764AVM) was rotated for 48 hours at 70 rpm. After milling the resulting dispersion was mixed with polypropylene wax as described in Example 1.
    Example 4
    Example 3 was repeated except that lead titanate was replaced with magnetite, a ferromagnetic material. Oleic acid was used as a surfactant to prepare a dispersion in 1-butanol. The particles were ball milled in a 2L stainless steel mill ego (U. S. Stoneware) using a 440 stainless steel grinding media. Half of the ego volume was filled with the grinding medium. The mill ego (Model 764AVM from U. S. Stoneware) was spun at 70 rpm for 7 days.
    Example 5
    The procedure of Example 4 was repeated except that magnetite was replaced with another ferromagnetic barium ferrite.
    Example 6
    The procedure of Examples 4 and 5 was repeated except that the ethoxylated alkyl phosphate ester, Rhodafac, as a surfactant RE-610 (Rhone-Poulenc) was used.
    Although the present specification has been described in detail with reference to specific embodiments, those skilled in the art will readily conceive of variations, modifications, and increments of such embodiments after understanding the above detailed description. Accordingly, the scope of the invention should be construed as the appended claims and equivalents thereof.
    权利要求:
    Claims (24)
    [1" claim-type="Currently amended] Providing a mixture of particulate material and a surfactant in the non-aqueous solvent, the surfactant being soluble in the non-aqueous solvent and stabilizing the particulate material from aggregation;
    Forming a dispersion of particulate material in a non-aqueous solvent;
    Combining the resulting particulate material dispersion in the non-aqueous solvent with a precursor polymer material (the non-aqueous solvent swells the precursor polymer near its boiling point); And
    Heating the blend of particulate material dispersion and precursor material to a temperature sufficient to evaporate the non-aqueous solvent (the boiling point of the non-aqueous solvent is higher than the temperature at which the precursor polymer can be mixed and not at the temperature at which the precursor polymer is polymerized or degraded). Low), a method for producing a small particle dispersion in a precursor polymer.
    [2" claim-type="Currently amended] The method of claim 1 wherein the particulate material is an inorganic material.
    [3" claim-type="Currently amended] The method of claim 2 wherein the particulate material is a metal oxide.
    [4" claim-type="Currently amended] The method of claim 1 wherein the metal oxide is a ferroelectric material.
    [5" claim-type="Currently amended] The method of claim 4, wherein the ferroelectric material is barium titanate.
    [6" claim-type="Currently amended] The method of claim 4, wherein the ferroelectric material is lead titanate.
    [7" claim-type="Currently amended] The method of claim 3, wherein the metal oxide is a ferromagnetic material.
    [8" claim-type="Currently amended] 8. The method of claim 7, wherein the ferromagnetic material is magnetite.
    [9" claim-type="Currently amended] 8. The method of claim 7, wherein the ferromagnetic material is barium ferrite.
    [10" claim-type="Currently amended] The method of claim 1 wherein the surfactant is an ethoxylated alkylamine.
    [11" claim-type="Currently amended] The method of claim 1 wherein the surfactant is a fatty acid.
    [12" claim-type="Currently amended] The method of claim 11, wherein the fatty acid is oleic acid.
    [13" claim-type="Currently amended] The process of claim 1 wherein the surfactant is an ethoxylated alkyl phosphoric acid ester.
    [14" claim-type="Currently amended] The method of claim 1 wherein the non-aqueous solvent is an aliphatic alcohol having about 3-10 carbon atoms.
    [15" claim-type="Currently amended] The method of claim 14, wherein the aliphatic alcohol is a normal alcohol having about 4-10 carbon atoms.
    [16" claim-type="Currently amended] The method of claim 15, wherein the aliphatic alcohol is 1-butanol.
    [17" claim-type="Currently amended] The method of claim 14, wherein the aliphatic alcohol comprises a branched alkyl group.
    [18" claim-type="Currently amended] The method of claim 14, wherein the aliphatic alcohol is 2-propanol.
    [19" claim-type="Currently amended] The method of claim 14, wherein the aliphatic alcohol is 2-butanol.
    [20" claim-type="Currently amended] The method of claim 1 wherein the non-aqueous solvent is a hydrocarbon.
    [21" claim-type="Currently amended] The method of claim 20, wherein the hydrocarbon is an aliphatic hydrocarbon having about 6-10 carbon atoms.
    [22" claim-type="Currently amended] The method of claim 20, wherein the hydrocarbon is an aromatic hydrocarbon.
    [23" claim-type="Currently amended] The method of claim 22 wherein the aromatic hydrocarbon is selected from the group consisting of benzene, toluene, cumene and xylene.
    [24" claim-type="Currently amended] The method of claim 1 wherein the solvent is 1,1-dimethyl-2-pyrrolidinone.
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    同族专利:
    公开号 | 公开日
    EP0942943A1|1999-09-22|
    DE69737560D1|2007-05-16|
    BR9713878A|2001-11-27|
    EP0942943B1|2007-04-04|
    WO1998024833A1|1998-06-11|
    SK75799A3|2000-02-14|
    AU5517898A|1998-06-29|
    AU721135B2|2000-06-22|
    US5800866A|1998-09-01|
    JP2001505248A|2001-04-17|
    DE69737560T2|2007-12-27|
    CN1239972A|1999-12-29|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    法律状态:
    1996-12-06|Priority to US08/758,749
    1996-12-06|Priority to US8/758,749
    1997-12-05|Application filed by 로날드 디. 맥크레이, 킴벌리-클라크 월드와이드, 인크.
    2000-11-25|Publication of KR20000069322A
    优先权:
    申请号 | 申请日 | 专利标题
    US08/758,749|US5800866A|1996-12-06|1996-12-06|Method of preparing small particle dispersions|
    US8/758,749|1996-12-06|
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