1529 results about "Interfacial polymerization" patented technology

The present invention generally relates to systems and methods of forming particles and, in certain aspects, to systems and methods of forming particles that are substantially monodisperse. Microfluidic systems and techniques for forming such particles are provided, for instance, particles may be formed using gellation, solidification, and/or chemical reactions such as cross-linking, polymerization, and/or interfacial polymerization reactions. In one aspect, the present invention is directed to a plurality of particles having an average dimension of less than about 500 micrometers and a distribution of dimensions such that no more than about 5% of the particles have a dimension greater than about 10% of the average dimension, which can be made via microfluidic systems. In one set of embodiments, at least some of the particles may comprise a metal, and in certain embodiments, at least some of the particles may comprise a magnetizable material. In another set of embodiments, at least some of the particles may be porous. In some embodiments, the invention includes non-spherical particles. Non-spherical particles may be formed, for example, by urging a fluidic droplet into a channel having a smallest dimension that is smaller than the diameter of a perfect mathematical sphere having a volume of the droplet, and solidifying the droplet, and/or by exposing at least a portion of a plurality of particles to an agent able to remove at least a portion of the particles.

A thin film composite or TFC membrane formed by interfacial polymerization of an organic and aqueous phase on a support membrane with nanoparticles in the discrimination layer and/or the support membrane, optimized by the selection of nanoparticles for membrane flux, hydrophilicity and to minimize thickness of the support membrane while maintaining the strength and ruggedness characteristics required for forward osmosis (FO) and/or pressure retarded osmosis (PRO) so that the flux flow paths are less tortuous than conventional support membranes and thereby provide increased flux flow.

This invention provides novel methods for the formation of biocompatible membranes around biological materials using photopolymerization of water soluble molecules. The membranes can be used as a covering to encapsulate biological materials or biomedical devices, as a “glue” to cause more than one biological substance to adhere together, or as carriers for biologically active species. Several methods for forming these membranes are provided. Each of these methods utilizes a polymerization system containing water-soluble macromers, species, which are at once polymers and macromolecules capable of further polymerization. The macromers are polymerized using a photoinitiator (such as a dye), optionally a cocatalyst, optionally an accelerator, and radiation in the form of visible or long wavelength UV light. The reaction occurs either by suspension polymerization or by interfacial polymerization. The polymer membrane can be formed directly on the surface of the biological material, or it can be formed on material, which is already encapsulated.

The invention relates to a hyperfiltration membrane or nanofiltration membrane with a multi-layered composite structure and a preparation method thereof. The hyperfiltration membrane or nanofiltration membrane is a polymer electrostatic spinning nanofiber membrane layer characterized in strong chemical resistance prepared through an electrostatic spinning method, a hydrophilic polymer ultra-thin separation layer obtained through interfacial polymerization, and a functional group surface modification functional layer formed through the grafting reaction of reactant gases on the surfaces of hydrophilic polymers, or a long-chain polymer surface modification functional layer formed through the grafting reaction of the reaction gases on the surfaces of the hydrophilic polymers, or a functionalgroup-containing long-chain polymer surface modification functional layer through the grafting reaction of the reaction gases with the functional groups on the surfaces of the hydrophilic polymers. The hyperfiltration membrane or nanofiltration membrane with the multi-layered composite structure has the advantages of high water flux, high cutting rate and stable chemical performances. The filtration membrane can be used for the production of domestic water, drinking water or water in special conditions, and is suitable for the medical field, food field, environmental protection field and the like.

The present invention relates to a composite membrane for gas separation and/or nanofiltration of a feed stream solution comprising a solvent and dissolved solutes and showing preferential rejection of the solutes. The composite membrane comprises a separating layer with intrinsic microporosity. The separating layer is suitably formed by interfacial polymerisation on a support membrane. Suitably, at least one of the monomers used in the interfacial polymerisation reaction should possess concavity, resulting in a network polymer with interconnected nanopores and a membrane with enhanced permeability. The support membrane may be optionally impregnated with a conditioning agent and may be optionally stable in organic solvents, particularly in polar aprotic solvents. The top layer of the composite membrane is optionally capped with functional groups to change the surface chemistry. The composite membrane may be cured in the oven to enhance rejection. Finally, the composite membrane may be treated with an activating solvent prior to nanofiltration.

The invention discloses a high-selectivity composite nanofiltration membrane and a preparation method thereof. The high-selectivity composite nanofiltration membrane comprises a nonwoven layer and a polymer porous supporting layer; and the porous supporting layer is provided with one or two polyamide surface layers prepared by reacting polyamine and/or amine polyalcohol with chlorine polyacyl. Compared with the prior art, by forming one or two polyamide surface layers on the porous supporting layer through an interfacial polymerization method, the nanofiltration membrane has increased thickness of a surface layer, has more smooth, hydrolysis-resistant, oxidation-resistant and scratch-resistant surface, and improves pollution resistance; and the surface of the membrane can carry negative or positive charges, so that the composite nanofiltration membrane has a high-selectively functional desalting layer; besides, the method for preparing the composite nanofiltration membrane is simple to operate, high water flux and desalination rate are ensured under low pressure, and the service life of the membrane component is prolonged.

The invention provides a process for the preparation of essential oil microcapsules comprising dissolving a di- or polyisocyanate into an essential oil, emulsifying the resulting mixture in an aqueous solution containing a di- or polyamine, and/or a di or polyhydroxy compound to effect encapsulation of said essential oil through interfacial polymerization, whereby there is formed a polyurea and/or polyurethane film around the essential oil droplets which film enhances the stability of said essential oil, reduces its evaporation rate and controls its release rate when applied to a substrate.

The invention discloses a crosslinking hyper branched polymer composite nanofiltration membrane as well as the preparation method thereof. The crosslinking hyper branched polymer composite nanofiltration membrane is prepared by taking an ultrafiltration membrane as a basement membrane and crosslinking hyper branched polymer as a selecting layer through hyper branched polymer and the interfacial polymerization of polybasic acid, polybasic acyl chloride, polybasic anhydride and polybasic amine; and the interfacial polymerization takes the mixed solution of water and ethanol as the water phase and n-hexane, n-heptane or n-octane as the organic phase. As the hyper branched polymer has the spheroidal structure, a plurality of nano-voids exist in the interior of the molecule, so as to enable the selecting layer of the crosslinking hyper branched polymer composite nanofiltration membrane to be looser, and leads the nanofiltration membrane to maintain high flux and retention rate under the lower operating pressure. The nanofiltration membrane can be used in the fields of medicament, foodstuff, environmental protection, etc. The composite nanofiltration membrane is applicable to the separation and the condensation of high valence ions, low valence ions, neutral particles, drugs, food additives, etc.

The invention discloses a preparation method of an aromatic polyamide film modified by a ZIF-8 type metal-organic framework material. A ZIF-8 filling polyamide composite film is prepared on an ultrafiltration bottom film by an interfacial polymerization method, wherein nano-grade ZIF-8 particles are added into an m-phenylenediamine aqueous solution and/or a trimesoyl hexane solution; a polyamide ultrathin skin layer, to which ZIF-8 is added, is formed through interfacial polymerization. The preparation method has the advantages that by the use of a ZIF-8 nano-grade aperture and a three-dimensional multi-hole structure, the selectivity or the permeability of the aromatic polyamide film is improved; the prepared ZIF-8 filling polyamide composite film can serve as a nanofiltration or reverse osmosis film for removing organic matters from the aqueous solution; when the adding ratio of an organic phase or water phase solution, to which ZIF-8 is added, is 0.05-0.15% (w/v), the performance of the film is the highest, and the permeation flux and the retention rate can be increased at the same time; furthermore, the nanofiltration or reverse osmosis performance of the two-phase adding film is higher than that of a single-phase adding film.

The invention discloses a grafted modified aromatic polyamide composite reverse osmosis membrane and a preparation method thereof, belonging to preparation technology of composite reverse osmosis membranes. The structural formula of the membrane is shown as follow. The preparation process comprises the following steps: taking a polysulphone membrane as a support membrane, preparing an aromatic polyamide composite reverse osmosis membrane to be grafted by an interfacial polymerization; enabling a graft modified solution containing 3-hydroxymethyl-5,5-dimethylhydantoin to contact the surface of the membrane to be grafted quickly for reacting, and conducting heat treatment to obtain the modified aromatic polyamide composite reverse osmosis membrane grafted with hydantoin derivatives. The invention has simple process, and the prepared membrane has the characteristics of good chlorine resistance and good microbial contamination resistance.

The invention discloses a preparation method of a high-throughput cross-linked polyimide solvent-resistant agent nanofiltration membrane. The preparation method comprises the following steps: interface polymerization, polyamines modification, chemical cross-linking and solvent activation. According to the preparation method disclosed by the invention, the polyamines modification on the surface of an original ecological membrane is carried out after the interface polymerization is carried out, so that the separation performance and the solvent-resistant agent performance of the membrane are obviously improved. The polyamines have more free amino groups, so that the cross-linking degree of an interface separation layer is greatly enhanced, and the solvent-resistant agent performance of the membrane is effectively improved; polyamines modified reagents containing different additives are adopted, so that the separation performance of the membrane can be improved. The preparation process disclosed by the invention is simple, and has good application prospects in the fields of separation of organic solvent systems and treatment on water containing organic solvents.

The invention relates to a high-water-flux forward-osmosis composite membrane and a preparation method thereof. The forward-osmosis composite membrane is a polysulfone-sulfonated polysulfone-inorganic filler blended/polyamide composite membrane. A traditional osmosis membrane is generally applied to a reverse-osmosis system, and if the traditional osmosis membrane is used in a forward-osmosis process, the water flux of osmosis is far lower than a theoretical value since the traditional osmosis composite membrane is large in thickness, the hydrophilicity of a supporting layer of a polyamide layer is poor so as to cause serious inner concentration polarization. The preparation method comprises the following steps: blending a polymer with a modifier to form film casting liquid; after scraping or leveling, performing non-solvent coagulating bath with water; by a phase-inversion method, preparing a polysulfone ultrafiltration membrane with good hydrophilicity, high porosity, uniform surface pore structure and narrow pore diameter distribution; and in a clean environment and at room temperature, airing the polysulfone membrane till the surface is dry, and growing a polyamide active layer on the surface of the polysulfone membrane by an interfacial polymerization method, thereby obtaining the forward-osmosis composite membrane with good hydrophilicity, high porosity, low thickness and high mechanical strength. The high-water-flux forward-osmosis composite membrane disclosed by the invention has the advantages that not only the osmosis flux is high, but also the reverse leakage of an extraction medium is low, and the selective permeability is good.

Thin film composite membranes on polyolefin structures may be prepared by interfacial polymerization on a polyolefin support. Polyolefin structures may have hollow and/or solid portions. The polyolefin structure may be hydrophilized prior to interfacial polymerization. The hydrophilized structure may also be treated with an aqueous monomer containing solution first, followed by the organic monomer containing solution. Alternatively, an organic monomer solution may be introduced first, followed by the aqueous monomer containing solution when treating a hydrophilized structure. The formed membrane may possess advantageous characteristics, including stability, hydrophilicity, predetermined pore sizes and/or solvent resistance.

A liquid crystal material containing polymer network forming material is microencapsulated by a method utilizing an interfacial polymerization which creates a combination of polyurethane and polyurea polymers or melamine fromaldehyde or urea formaldehyde polymer which form the capsule walls surrounding the discrete liquid crystal droplets. The prepolymer of urethane acrylate and acrylate within the liquid crystal capsules is cured under UV light irradiation to form a web-like structure and induce the formation of polydomain configuration of nematic director. This allows to produce the display having faster switching property and showing significant lower threshold voltage.

It is known to encapsulate various materials in polyurea microcapsules, but obtaining satisfactory microcapsules incorporating alcoholic materials has proven difficult. A process has now been found where polyurea microcapsules are formed by interfacial polymerization between an aqueous phase and a water-immiscible phase, and properties, particularly the solubility parameters, of the water immiscible phase are closely matched to corresponding properties of the polyurea. Microcapsules prepared by this process have improved stability, mechanical strength and controlled release properties.

This invention relates to preparation method of a facies change stuff microcapsule. It takes paraffin as phase-change material, takes toluene diisocyanate and urea-formaldehyde resin as cyst wall stuff, by interfacial polymerization and in situ polymeric method to carry out microencapsulate, to prepare double deck, microcapsule packed paraffin phase-change material. This method could prepare microcapsule phase-change material that contain any specification paraffin from 1% to 70%. Transformation temperature of this phase-change material is adjustable from 0 to 70 deg.C. This compound phase-change material can directly apply to construction region, textile region, and martial region and so on.

The invention discloses a preparation method of a high-throughput anti-pollution composite nanofiltration membrane. The preparation method comprises the following steps: inorganic nanoparticles are uniformly dispersed in a porous polymer supporting layer, a surface active agent is added in solution A, a polyamide layer is prepared on the porous polymer supporting layer through interfacial polymerization, hot water soaking treatment and glycerol moisturization treatment are adopted, and then drying is performed, and thus, the high-throughput anti-pollution composite nanofiltration membrane is prepared. According to the method, the porous supporting layer microstructure is changed by inorganic nano particles, the surface active agent is added in the solution A, and the flux and the antifouling property of the composite nanofiltration membrane are improved. The preparation method is easy, the raw material is cheap, the preparation process is simple and the method has good industrial applicability.

Polymer nanofibers, such as polyaniline nanofibers, with uniform diameters less than 500 nm can be made in bulk quantities through a facile aqueous and organic interfacial polymerization method at ambient conditions. The nanofibers have lengths varying from 500 nm to 10 μm and form interconnected networks in a thin film. Thin film nanofiber sensors can be made of the polyaniline nanofibers having superior performance in both sensitivity and time response to a variety of gas vapors including, acids, bases, redox active vapors, alcohols and volatile organic chemicals.

The invention relates to a method for preparing a multi-layer composite-structure filter membrane with a plasma pretreatment method. According to the filter membrane, a polymer nano-grade fiber film layer prepared through an electrostatic spinning method, and a hydrophilic polymer ultra-thin separation layer are sequentially arranged on a non-woven fabric support layer substrate. Before the hydrophilic polymer ultra-thin separation layer is prepared through an interfacial polymerization reaction, the plasma pretreatment is carried out on the surface of the polymer nano-grade fiber film layer, such that functional groups are grafted on the surface of the polymer nano-grade fiber. Therefore, polymer nano-grade fiber film surface property is improved, such that the polymer ultra-thin separation layer can be better compounded, and the filtering performance of the multi-layer composite-structure filter membrane is comprehensively improved. The multi-layer composite-structure filter membrane provided by the invention has the characteristics of high water flux, high retention rate, and stable chemical property. The film can be used in productions of water used in special conditions, such as domestic water and drinking water. The film is suitable to be used in fields such as medicines, foodstuffs, environment protection, and the like.

The invention relates to a high-performance composite nanofiltration membrane with resistance to oxidation of an organic solvent and chlorine, as well as a preparation method and application of the membrane. According to the preparation method, an interfacial polymerization process is interfered by supporting electrolyte, so that the density of aqueous phase monomers adsorbed on the surface of the membrane is increased, a base membrane is closely connected with an active layer, and the active layer is compact while the thickness of the active layer is reduced; therefore, high permeation flux can be obtained while low-concentration monomers are used, and high selectivity is maintained. The composite nanofiltration membrane has the properties of resisting to oxidation of the organic solvent and chlorine, under the pressure of 1.0 MPa and at the temperature of 25 DEG C, the flux of 2g/L sodium sulfate aqueous solution is 25-65 L/(m<2>.h), and retention rate is 85-99%; the flux of 2g/L sodium chloride aqueous solution is 30-60 L/(m<2>.h), and the retention rate is 50-75%.