189 results about "Living polymerization" patented technology

A process for the preparation of a latex polymer consistent with E/A (emulsion/aggregation/coalescence) toner manufacture. The process utilizes a standard (universal) latex composition and involves chain-transfer agent partitioning, emulsion polymerization that provides a latex polymer with a wide range of molecular properties. In particular, the process customizes a wide range Mw (weight average molecular weight) latex, without substantially varying the Mn (number average molecular weight) and hence, without substantially varying Tg (glass transition temperature) such that good toner performance is maintained. In a preferred process, a latex polymer is prepared by mixing a seed particle latex, generated by aqueous emulsion polymerization of a first portion of a monomer emulsion, with a second portion of the monomer emulsion and at least one chain-transfer agent. The mixing is done in the presence of a free-radical initiator and heated, and wherein the monomer emulsion comprises a mixture of polymerization reagents of at least one monomer, at least one chain-transfer agent, at least one surfactant, and water. This process may be applied to core-shell polymerization as well. These latex polymers are ideally suited in the manufacture of toner and developer for electrophotographic imaging and printing.

A method for catalytic polymerization of alpha-olefin monomers using an ultra-high activity non-metallocene pre-catalyst featuring an amine bis(phenolate) ligand-metal chelate, having general formulas of [{(O)1R1R2R3R4(C6)1(CH2)1(RnY-T)N(CH2)2(C6)2R5R6R7R8(O)2}MX1X2] and [{(O)1R1R2R3R4(C6)1(CH2)1(RnY-T)N(CH2)2(C6)2R5R6R7R8(O)2}MX3], where, M, O, and N, are metal, oxygen, and, nitrogen; X1, X2, and X3, are ligands bonded to M; R1 through R8 are radicals; (RnY-T) is an optional non-donor or donor group bonded to N. The relatively stable and simply synthesized pre-catalyst is activated by a co-catalyst under mild reaction conditions, producing exceptionally reactive polymerization of a wide variety of alpha-olefin monomers, and forming a variety of poly(alpha-olefin) products, having high molecular weight and low molecular weight distribution (PDIs close to 1). Living polymerization is performed at or above room temperature, along with achieving block co-polymerization of alpha-olefin monomers at room temperature, and producing polymers and oligomers having a wide range of molecular weights. The catalyst formed during reaction remains "alive' for as long as 31 hours, for producing a polymer with a molecular weight as high as 450,000 grams/mole.

Bis(salicylaldiminato)titanium complex with optionally substituted phenyl or cyclohexyl on nitrogen catalyzes highly syndiospecific polymerization of propylene. Syndiotactic polypropylene with defects of the type rmr having [rrrr] content greater than 0.70 and block copolymer containing block(s) of the syndiotactic polypropylene and block(s) of poly(ethylene-co-propylene) and/or poly(alpha-olefin-co-propylene) are obtained. Certain of the catalysts provide living polymerization. Living olefin polymers and olefin terminated oligomers and polymers are also products.

The invention provides a hydrophilic bactericidal anti-contamination reverse osmosis membrane and a preparation method thereof. A bactericidal high-molecular polymer and an antibacterial polymer are grafted on the surface of a reverse osmosis membrane through a reversible addition-fragmentation chain transfer polymerization (RAFT) living polymerization method, so that the hydrophilic bactericidalanti-contamination reverse osmosis membrane is obtained, the method utilizes free amino groups on the surface of a polyamide functional layer to link a RAFT chain transfer agent in situ through an amide condensation reaction, and functional layers with different thicknesses and different molecular weights are controllably grafted, such as an amphoteric ion functional layer with hydrophilic properties and a quaternary ammonium salt functional layer with bactericidal performance. The anti-contamination reverse osmosis membrane prepared by the method still has excellent anti-contamination characteristics without sacrificing the performance of the original membrane, the long-term anti-contamination ability of the original membrane in a complex operating environment is improved, and the purposes of inhibiting the growth of bacteria and reducing attachment of microorganisms on the membrane are achieved.

The invention relates to a process method of synthesizing medical biodegradable material by bionic organic carbamidine catalyst, especially a new process method of synthesizing medical biodegradable polyester polymers, and its character: it uses nontoxic metal-free bionic acetic hexabutyl carbamidine and acetic tetramethyl dibutyl carbamidine as catalysts to make the ring-opening polymerization reaction of cyclo-ester monomers (L-lactide, D, L-lactide, glycollide, epsilon-caprolactone), thus synthesizing high-organism safety medical biodegradable materials. The new process method avoids cytotoxinic stannous octoate catalyst. The process adopts body polymerization method and the polymerization reaction has the characters of controlled and active polymerization reaction, not only able to synthesize homopolymers but also be used in synthesizing controlled composed block copolymer.

The invention relates to a functional segmented copolymer based on living polymerization. The functional segmented copolymer has a structural formula as shown in the specification, wherein a segment A is prepared by polymerizing at least two olefinic bond unsaturated monomer segments; A1 is a polar olefinic bond unsaturated monomer with an amino functional group, an acid functional group or methacrylic acid glycidyl ester; A2 is a copolymerization prompting monomer; a segment B is prepared by polymerizing at least one or more than one olefinic bond unsaturated monomers; x, y and z are the polymerization degrees; z ranges from 0 to 400; the number-average molecular weight of the segment A is 500-50000; the number-average molecular weight of the segment B is 1000-20000. By introducing the copolymerization prompting monomer A2, the defects in preparing the conventional segmented active copolymer are avoided, not only can the functional segmented copolymer prepared in an ordinary solvent, but also the compatibility of a dispersing agent and a substrate of the functional segmented copolymer is greatly improved, and the functional segmented copolymer is good in dispersion effect for carbon black, organic dye and the like, low in color paste velocity, good in paint film color showing, and particularly high in blackness of the carbon black.

A betaine-containing polymer film that can be formed on a substrate surface using living polymerization such as controlled radical polymerization is disclosed.

The invention discloses a living polymerization preparation method for a polyacrylic acid ball brush and application of the polyacrylic acid ball brush and particularly discloses the polyacrylic acid ball brush prepared by the living polymerization method and the application of the polyacrylic acid ball brush in the protein high density immobilization. The method comprises steps of synthesizing a novel silylanized reversible addition-fragmentation chain transfer (RAFT) polymeric chain transfer reagent; fixing the RAFT polymeric chain transfer reagent to a spherical solid phase carrier surface through a reaction; forming a polyacrylic acid brush structure on the carrier surface which is grafted with the RAFT polymeric chain transfer reagent through the RAFT polymerization; and obtaining the polyacrylic acid ball brush. The polyacrylic acid ball brush material is subjected to activation and protein immobilization, the compound of the ball brush and the protein is obtained, ant the application in the protein high density immobilization is achieved. By the aid of the method, the synthetic process and the synthetic time of the polyacrylic acid ball brush are shortened, the reaction efficiency is improved, and the polyacrylic acid ball brush has high grafting density and carboxyl content and provides more positions for protein immobilization.

The invention relates to a Schiff base transition metal complex containing alkoxy groups, a preparation method thereof and application of a catalyst composition composed of the transition metal complex and aluminum alkyl in catalyzing ethene polymerization, belonging to the technical field of catalysts. The preparation method for the Schiff base transition metal complex containing alkoxy groups comprises the following steps: synthesizing Schiff base ligand through a condensation reaction between substituted salicylaldehyde and an amine compound; reacting the ligand with an alkali metal compound to obtain a ligand salt solution; and reacting the ligand salt solution with MCl4 to prepare the Schiff base transition metal complex. The preparation method is simple; and when used for ethene polymerization, the synthesized Schiff base transition metal complex containing alkoxy groups has the following advantages compared to the prior art: common aluminum alkyl is used as a cocatalyst to substitute expensive MAO during polymerization, and the catalyst composition has high activity under the condition of a small usage amount of the cocatalyst. Hexane is used as a solvent to substitute toluene during polymerization, which is favorable for industrial introduction.

A method for evaluating the polymer growth inhibition ability of a compound or compounds is disclosed wherein the method comprises: A) weighing a dry seed of insoluble polymer capable of growing via a living polymerization mechanism; B) subjecting the seed of insoluble polymer to conditions capable of causing a living polymer to grow via a living polymerization mechanism; C) drying the seed; and D) weighing the seed a second time to determine any increase in weight; wherein the polymer growth inhibition ability of the compound or compounds is inversely proportional to any increase found in weight of the seed.

Belonging to the technical field of polymer synthesis, the invention relates to a frustrated Lewis pair FLP catalyzed vinyl polar monomer living polymerization method. A vinyl polar monomer is adoptedas the monomer raw material for conjugate addition polymerization under the synergic catalysis of a frustrated Lewis pair, in terms of mole, Lewis acid is greater than Lewis base and smaller than themonomer, and the ratio of the monomer to the Lewis base is 20-3200:1, the reaction temperature is room temperature, and the reaction time is 30sec-24h. The method provided by the invention has the characteristics of easily available raw materials, convenient operation, mild reaction conditions, rapidity, high conversion rate, wide monomer adaptability and the like, also the catalyst dosage is small, and the initiation efficiency is close to 100%, therefore the method is living controlled polymerization, and can realize random copolymerization and block copolymerization between different polarmonomers.

A method of manufacturing a charged particle, comprising: a) providing a mother particle; and b) forming a coating layer that covers at least a part of a surface of the mother particle wherein the step b) includes: coupling a first chemical compound having at least a part where is going to be a starting point of living polymerization to the surface of the mother particle; and polymerizing a second chemical compound having an ionic group or a functional group convertible to an ionic group so as to form a polymer through the living polymerization that starts from the starting point of the first chemical compound.

A process for forming a fluorocarbon polymer film on a substrate is disclosed. A self-assembled monolayer (SAM) containing an initiator for living polymerization such as controlled radical polymerization is formed on the surface of the substrate followed by living polymerization such as controlled radical polymerization of a polymerizable fluorocarbon monomer component.

The invention relates to a method for carrying out living polymerization by directly using an industrial-grade monomer, in particular to a method for preparing polymethyl methacrylate by carrying out atom transfer radical polymerization (AGET ATRP) reaction generating a catalyst through electron transfer by directly using the monomer, i.e. industrial-grade methyl methacrylate containing a polymerization inhibitor, belonging to the field of organic polymerization. The method comprises the following steps of: adding the monomer, an initiator, the catalyst and a coordinating agent according to the mole ratio of monomer:initiator:catalyst:coordinating agent=(100-1000):1:(0.05-1):(0.15-3) by taking the industrial-grade methyl methacrylate as the monomer; and carrying out the atom transfer radical polymerization (AGET ATRP) reaction generating the catalyst through the electron transfer to synthesize a high molecular polymer under the catalysis of ferric salt. The invention decreases the steps of eliminating the polymerization inhibitor by carrying out the AGET ATRP polymerization by directly using the industrial-grade methyl methacrylate containing the polymerization inhibitor, simplifies the polymerization process and greatly reduces the production cost.

The invention provides a preparation method for a polymeric nanometer microsphere. The preparation method comprises the following steps: with trithiocarbonate represented by a formula (I) as a chain transferring agent, carrying out RAFT living polymerization to synthesize a gradient copolymer; dissolving the gradient copolymer in an organic solvent and then adding water to form a polymeric micelle solution, wherein the organic solvent and water are intermiscible; and adding the polymeric micelle solution into an aqueous solution of an inorganic salt and carrying out solvent displacement so as to obtain the polymeric nanometer microsphere, wherein a volume ratio of the polymeric micelle solution to the aqueous solution of the inorganic salt is 0.01 to 1. The polymeric nanometer microsphere prepared by using the method has good stability and uniformity, narrow particle size distribution and photoresponse characteristics and the surface of the microsphere is rich in carboxyl groups, thereby facilitating application of the polymeric nanometer microsphere as a good carrier for drugs and proteins. Moreover, the method provided by the invention has the advantages of simpleness, easy practicability, good repeatability, low energy consumption, extensive applicability and easy realization of industrialization.

A macromolecule includes at least one polymer chain with at least one functionality. The polymer can include unsaturated mer units and can be provided via anionic and pseudo-living polymerization techniques. In either technique, the functionality can include at least one 5- or 6-membered ring which includes a secondary amine group and at least one additional heteroatom; in the latter technique, the functionality can include a hydrazone radical. Such polymers can be used to provide compositions that also include particulate fillers, such compositions being useful for the production of vulcanizates.