228results about How to "Improve copolymerization performance" patented technology

The present invention relates to a method for making a fluoropolymer comprising an aqueous emulsion polymerization of one or more fluorinated monomers wherein said aqueous emulsion polymerization is carried out in the presence of an oligomer that comprises one or more ionic groups, has a partially fluorinated backbone, a number average molecular weight of not more than 2000 g / mol and that has a combination of repeating units different from that of the fluoropolymer that is being produced by the polymerization of said one or more fluorinated monomers. Since the polymerization of the one or more fluorinated monomers to produce the desired fluoropolymer is carried out in the presence of the oligomer, the resulting dispersion will contain the oligomer in addition to the fluoropolymer. Thus, in a further aspect, the invention relates to an aqueous dispersion of a fluoropolymer comprising the oligomer.

Disclosed is a water- and oil-repellent agent comprising the following fluorine-containing copolymer (A). The fluorine-containing copolymer (A) comprises: (a1) a fluoroalkyl group-containing polymerizable monomer of the formula:  wherein Y is a divalent organic group [for example, an aliphatic group having 1 to 10 carbon atoms, an aromatic or cycloaliphatic group having 6 to 10 carbon atoms, a —SO2N(R1)R2— group (in which R1 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R2 is an alkylene group having 1 to 10 carbon atoms), a —CON(R1)R2— group (in which R1 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R2 is an alkylene group having 1 to 10 carbon atoms), or a —CH2CH(OY1)CH2— group (in which Y1 is a hydrogen atom or an acyl group having 1 to 4 carbon atoms)]; and  Rf is a linear or branched fluoroalkyl or fluoroalkenyl group having 1 to 6 carbon atoms; and (a2) vinylidene chloride.

The present invention is thus directed to a cement additive which comprises a copolymer (A) obtained by polymerizing a monomer mixture (K), wherein;said monomer mixture (K) comprises a polyalkylene glycol ester monomer (I) represented by the general formula (1): a polyalkylene glycol ester monomer (II) represented by the general formula (2): and a carboxylic acid monomer (III) represented by the general formula (3):

A catalyst for polymerization or copolymerization of ethylene is prepared through dissolving magnesium halide in organic epoxy compound, organic phosphorus compound or inertial diluent, adding alkane educing aid, porous inertial carrier and halide of Ti, and educing. It is possible to add alcohol compound and / or electron donor. Its advantages are high activity and copolymerizing performance, and high sensitivity to hydrogen regulation.

The present invention provides catalyst active components used in ethylene polymerization or polymerization, the catalyst precursors as well as the preparation method of the catalyst active components. The catalyst active components in the present invention comprise: magnesium compounds; titanium compounds Ti (OR) 4-n X n , where X is halogen, R is alkyl, n is O or an integer less than or equals 4; catalytic accelerant which is of chelate function and is of matching iron of [O,O] or[O,N]; Electron donor with silicon; Organic ester R'OH, where R' represents alkyl; and halogenated hydrocarbon. The catalyst precursors provided in the present invention are firm particles with high catalytic activity, stable dynamics and good polymerization and hydrogen-sensitive performance. The polyethylene products obtained from the catalyst precursors are particles of good shape, with the particle diameter evenly distributed. The density of the particles is high.

The invention relates to a copolymerization flotation-sedimentation tank. The copolymerization flotation-sedimentation tank comprises a multi-channel folded plate copolymerization flocculation basin, a flotation-sedimentation tank and an air dissolving system, wherein the multi-channel folded plate copolymerization flocculation basin is used for realizing the coagulation and the copolymerization of flocculates and microbubbles; the flotation-sedimentation tank is connected to the rear end of the multi-channel folded plate copolymerization flocculation basin and is used for separating foamed flocculates from water flow and precipitating settleable flocculates which cannot float; and the air dissolving system is connected with a water outlet end of the flotation-sedimentation tank and is connected with the multi-channel folded plate copolymerization flocculation basin and the flotation-sedimentation tank to supply high-pressure backflow gas dissolved water to the multi-channel folded plate copolymerization flocculation basin and the flotation-sedimentation tank. According to the copolymerization flotation-sedimentation tank, the high-pressure backflow gas dissolved water is fed for three times, by virtue of organic combination with a flocculation process, a microbubble and flocculate copolymerized environment is created, and the produced foamed flocculates are stable and are not easily separated, so that the problems that the adhesion efficiency of particles is low, the trapping effect is not ideal, the adhesion of the foamed flocculates is instable, and the like of a traditional dissolved air flotation process are solved, and the coagulation, air floatation and sedimentation processes are organically combined and integrated; and the copolymerization flotation-sedimentation tank has prominent superiority in the treatment of water quality in high-algae, low-turbidity and burst high-turbidity reservoirs.

The invention provides a catalyst active ingredient used for propylene polymerization or copolymerization, a catalyst precursor containing the active ingredient, and a preparation method thereof. The catalyst active ingredient comprises a magnesium compound, a titanium compound Ti(OR)4-nXn, a chelated corrdination type electron donor, a selectively added diester electron donor, a siliceous electron donor, organic alcohol R'OH and halogenated hydrocarbons, wherein X is halogen; R is alkyl; n is 0 or an integer which is less than or equal to 4; and R' is alkyl. The catalyst precursor provided by the invention has the advantages of solid particles, high catalytic activity, stable dynamic curve, strong copolymerization performance, high hydrogen regulation sensitivity and so on, and a polypropylene product prepared by utilizing the catalyst precursor has the advantages of good particle shape, uniform particle size distribution, high fusion index of polymers, high bulk density and a small quantity of powder.

A reactive emulsifier comprising a compound of formula (I), which makes polymerization stability satisfactory and is capable of improving the water resistance etc. of the polymer film to be obtained.In the formula (I), D represents a polymerizable unsaturated group represented by the chemical formula D-1 or D-2; m1 represents a number of 1 or larger; R1 represents an alkyl group having 1 to 12 carbon atoms; m2 represents a number of 0 to 4; and the sum of m1 and m2 is 1 to 5. R2 represents a hydrocarbon group having 6 to 30 carbon atoms; A represents either an alkylene group or a substituted alkylene group which has 2 to 4 carbon atoms; and n is in the range of 0 to 1,000. X represents a hydrogen atom or an anionic hydrophilic group which is —(CH2)a—SO3M etc.R3 represents a hydrogen atom or methyl.

The invention provides ethylene-propylene-diene methylene taking liquid-state oligomers of diolefin as a third monomer and a method for preparing same. Combined propylene cells account for 20 to 45 molar percent of the ethylene-propylene-diene methylene, the third monomer which is a liquid-state oligomer of diolefin accounts for 0.5 to 15 molar percent of the ethylene-propylene-diene methylene, and the total molar percentage of the combined cells of ethylene, propylene and the third monomer is 100 percent; and the liquid-state oligomer of diolefin of the third monomer is selected from liquid-state oligomers with different double-bond structures and double-bond contents, including the liquid polybutadiene containing 20 to 80 percent of 1,2-strucutres and liquid polyisoprene containing over 90 percent of 1,4-strucutres. Because the side chains contain more double bonds, the ethylene-propylene-diene methylene has good curing and processing properties, and can vulcanize sulfur; the polymer has the molecular weight distribution indexes from 2 to 10; the ethylene-propylene-diene methylene can be used for manufacturing industrial rubber products of automobile parts, waterproof materials, telecom cables and the like.

A catalyst for the polymerizing and copolymerizing of ethene and its preparing process is disclosed. The active component of said catalyst is prepared through dissolving magnesium halide in organic epoxy compound, organic P compound, organic alcohol, or inertial deluent to obtain uniform solution, educing out the solid deposition contain Mg / Ti by adding educing assistant and Ti halide or its derivative, and treating the Ti contained component by hydrogenating improver. Its advantages are high activity, high hydrogenating sensitivity and good granular form.

The invention relates to ingredients of a catalyst for vinyl polymerization. The ingredients comprise the following reaction products: (1) a magnesium compound, (2) an organic alcoholic compound, (3) an organic silicon compound, (4) a non-ionic surfactant, and (5) a titanium compound, wherein the structural formula of the organic silicon compound is at least one of R<1>xR<2>ySi(OR<3>)z, wherein R<1> and R<2> are respectively alkyl or halogen of which the carbon numbers are 1 to 10; R<3> is alkyl of which the carbon number is 1 to 10; x, y and z are integral numbers; x is larger than or equal to 0 and smaller than or equal to 2; y is larger than or equal to 0 and smaller than or equal to 2; z is larger than or equal to 0 and smaller than or equal to 4; x+y+z=4; the non-ionic surfactant is at least one of the periodic copolymers of a poly-oxyethylene ether compound, a carbon oxo alcohol ethoxy compound and an epoxy compound. The catalyst is relatively high in catalytic activity and copolymerization performance; a polymer prepared with the catalyst is relatively high in bulk density and relatively small in size distribution; the catalyst is suitable for homopolymerization of ethylene or copolymerization of ethylene and other Alpha-olefin.

This invention provides an olefin polymerization catalyst active component suitable for ethene polymerization or copolymerization reaction of ethene and alpha-olefin and a catalyst containing said active component, which introduces electronic compound and halohydrocarbon into an active component containing Ti to get a high-active olefin polymerized catalyst. When carrying out olefin polymerrization by the catalyst prepared in such method, one can get the polymer in large density and resin in good size.

A spherical Ziegler-Natta catalyst used for sludge or gas-phase polymerization of ethene and its preparing process are disclosed. Said catalyst along with organoaluminum cocatalyst can be used for the homopolymerization of ethene or copolymerization of ethene and alpha-olefin to obtain spherical products.

The invention relates to a supported vanadium alkene polymerization catalyst, which comprises a porous inorganic carrier, a catalyst composite modifying component, a vanadium containing component, and a catalyst activating component; wherein the catalyst composite modifying component is the product of high temperature burning of a first soluble compound and / or a second soluble compound, and the vanadium containing component is the product of high temperature burning of a third compound. Compared with the conventional Ziegler-Natta vanadium catalysts, the provided supported vanadium alkene polymerization catalyst has the advantages of higher and more stable activity, wider range of polymerization temperature, and excellent copolymerization performance.

Disclosed is a catalyst for olefin polymerization composed of a crosslinked metallocene compound (A-1) represented by the general formula [1-1] below and at least one or more compounds (b) selected from organic aluminum oxy compounds (b-1), compounds (b-2) forming an ion pair, and organic aluminum compounds (b-3). [1-1] (In the general formula [1-1], R<1>, R<2>, R<3>, R<4>, R<5>, R<8>, R<9> and R<12> respectively represent one selected from a hydrogen atom, a hydrocarbon group and a silicon-containing group; R<6>, R<7>, R<10> and R<11> are not hydrogen atoms and respectively represent one selected from a hydrocarbon group and a silicon-containing group; R<13> and R<14> respectively represent a hydrogen atom, a hydrocarbon group other than a methyl group or the like; M represents Ti, Zr or the like; Y represents carbon or the like; Q represents a halogen or the like; and j represents an integer of 1-4.

A catalyst for the ethylene polymerization and its preparing process and application are disclosed. Said catalyst contains an inorganic oxide as carrier, and several active components, carried by said carrier, which are alkyl metal compound, halide, dual-function compound able to react with dihydroxy magnesium, Mg compound, and Ti compound. Its advantages are better hydrogen regulating performance and balanced activity, and low static electricity.

The invention provides an organic chromium catalyst for ethylene polymerization and a preparation method thereof. The catalyst comprises a main active catalyst, an inorganic oxide carrier, a modifier and a cocatalyst, wherein the main active catalyst is a chromium salt, and the content of the main active catalyst in the catalyst is 0.01-5% by mass; technical requirements of the carrier inorganic oxide comprise that the surface area is about 200-700m<2> / g, the pore volume is about 1-4cc / g, the aperture is about 60-700 and the particle dimension is about 10-200mum; the modifier is a recovery liquid for the preparation of an alkylsilane chromate catalyst; and the cocatalyst is an alkyl compound of Al, Li, B and Zn. The organic chromium catalyst for the ethylene polymerization provided in theinvention has the advantages of high activity, proper induction time, and suitableness of the production of wide molecular weight distribution range polyethylene products; and the preparation method provided in the invention has the advantages of simple synthetic technology and low preparation cost.

The invention belongs to polyethylene catalysts, and particularly relates to a titanium fluoride modified load type chrome alum double-active center catalyst. The titanium fluoride modified load type chrome alum double-active center catalyst comprises an inorganic carrier and loaded active components and modified components. The active components comprise chromium oxides and vanadium oxides, and the modified components comprise fluorine and titanium. According to the catalyst, the content and distribution of comonomers are improved, the number of the comonomers inserted into a low molecular weight end is reduced, the number of the comonomers inserted into a high molecular weight end is increased, and therefore more chalaza molecules can be formed easily, and polyethylene products with better performance are prepared. Meanwhile, the catalyst has the advantages of being high in activity, sensitive in hydrogen regulation response performance and the like. The invention further provides a preparation method of the catalyst. The inorganic carrier is firstly loaded with one of the modified components, and then loaded with the rest of the components, the process is reasonable, and industrial production is easy.

The invention discloses a strain of caries resistant lactobacillus plantarum K41 and application thereof. Lactobacillus plantarum K41 provided by the invention is preserved in Common Microorganism Center of Chinese Microorganism Strain Preservation Management Committee, with preservation number of CGMCC No.15462, and preservation date of March 20, 2018. The strain is separated from farmyard self-made pickles in Yanan Road, Shunqing District, Nanchong, Sichuan, grows well on an MRS agar culture medium, can inhibit growth of streptococcus mutans UA159, forming of exopolysaccharide, degradation of hydroxyapatite, and forming of a biological film, has good auto-agglutination and copolymerization capability, is good in tolerance for antibiotics, salt and acid, and is easy to be planted in the oral cavity. Animal experiment shows that K41 can inhibit rat enamel demineralization and caries degree, can be applied to functional food, and has very important meaning for body health.

The invention discloses a phosphate surfactant, of which the chemical formula is: H-(CF2)m-CH2-O-(CH2CH2O)n-PO(OM)2, wherein m is equal to 2, 4, 6 or 8, n is equal to 0 or 1, and M is NH4+ or Na+. The invention also discloses a method for preparing trifluorochlor oethylene polymer emulsion or solid with the phosphate surfactant as an emulsifier. The surfactant can be used for emulsion polymerization of fluoride-containing monomer. Used as the emulsifier, the surfactant can achieve a high polymerization rate, good dispersion stability, high yield, excellent copolymerization performance and / or multiple particle sizes (including small particle size). Besides, the method can realize polymerization by only using conventional equipment, is easy and convenient to operate and has a low cost, and does not cause environmental pollution during and after reaction.

The present invention provides a catalyst containing mono schiff base and monocyclopentadiene gliand. The said catalyst is used in polymerization of olefine and can be used to obtain polymer with high molecular weight and high copolymerized monomer inserting rate.

The invention belongs to the field of olefin polymerization catalysts, and particularly provides a solid catalyst component and catalyst system for olefin polymerization, and an olefin polymerizationmethod. The solid catalyst component comprises a reaction product of the following components: 1) an alkoxy magnesium compound; 2) a titanium compound; and 3) an internal electron donor compound, wherein the internal electron donor compound comprises at least one selected from cyclotetraveratrylene represented by a formula (I) and derivatives of the cyclotetraveratrylene. According to the solid catalyst component disclosed by the invention, polymerization activity, hydrogen regulation sensitivity and copolymerization performance of the polyolefin catalyst are improved by introducing the cyclotetraveratrylene and the derivative of the cyclotetraveratrylene as the internal electron donor.

The invention discloses an emulsion strength-increasing agent which is special for papers and its preparation method, the preparation method includes the following steps: reacting the initiating agent, the mixed monomer combined with phenylethene and acrylic ester, water and composite emulsifier 0.5-1.5 hours and under 50-65deg.Cwhich total amount is 0.2-2.0%; drip-adding the excess mixing monomer combined by the initiating agent, acrylic nitrile, water-solubility monomer and basic ion monomer, the drip-adding time is 2-5 hours; heating the body system temperature to 75-90deg.C after the drip-adding is completed, and reacting 1-4 hours under the temperature; adjusting pH valve to 6.5-8.0 and the product is prepared. The emulsion strength-increasing agent in the invention has the advantages of small particle size, easy adsorbing, high effective ingredients, stable performance and etc.; it can be used in the wet part adding when paper making, it can significantly improve the dry strength and tear resistance of paper, at the same time, the ring compression strength and folding resistance of paper is markedly improved.

The invention relates to a diimine metal complex as shown in a formula I and a preparation method and application thereof, and the diimine metal complex is used as a main catalyst of a catalyst for olefin polymerization and can catalyze ethylene polymerization at a relatively high temperature to prepare high-molecular-weight branched polyethylene.

The invention relates to a charcoal circulation type co-coagulation flotation tank water purification system and method. Mechanical flocculation, dissolved air flotation and an inclined plate settling basin are organically combined so as to form copolymerization dissolved air flotation, and mechanical flocculation and dissolved air flotation are organically combined through a copolymerization dissolved air flotation process, so that the stability of bubble floc is improved. Ozone oxidation and biological activated carbon are organically combined, so that the decomposition ability of powder biological activated carbon on organic matters is greatly improved. Air flotation and ozone oxidation are organically combined, so that an ozone oxidation effect is greatly improved. Mechanical flocculation, copolymerization air flotation, the biological activated carbon and inclined plate settling are organically combined, so that under the conditions of effectively controlling the rotate speed, reducing the hydraulic loss and the like, an aquatic organic matter is removed, and the stable bubble floc is formed. The system provided by the invention is flexible in process and operation manner, can be beneficial for effectively reducing the operation cost, has the advantages of high adaptability to water quality change, high efficiency, convenience in operation and the like, and has a wide application prospect.

The invention relates to the field of olefin polymerization catalysts, and specifically relates to a solid catalyst component and catalyst system used for olefin polymerization, and an olefin polymerization method. The solid catalyst component includes reaction products of the following components: 1) a liquid component containing magnesium, 2) a titanium compound, 3) an internal electron donor compound, and optionally selected 4) an assistant precipitating agent. The internal electron donor compound is selected from at least one of cyclotriveratrylene and derivatives thereof shown as a formula (I), and M1-M6 are selected from hydrogen, hydroxy, amino, an aldehyde group, a carboxyl group, an acyl group, halogen atoms. Through the introduction of the cyclotriveratrylene and derivatives thereof as internal electron donors, the polymerization activity, hydrogen response and copolymerization performance of the polyolefin catalyst can be enhanced. The structure of the cyclotriveratrylene and the derivatives thereof is shown as the formula (1).

The invention relates to a dual core metallocene catalyst and a preparation method and applications thereof. The catalyst comprises two parts: a main catalyst and a co-catalyst; wherein the main catalyst is formed by bridging two molecules containing IVB-IIB group transition metal atoms with an organic metal complex formed by a cyclopentadienyl group or a substituted cyclopentadienyl group throughrigid groups. The catalyst is applied to ethylene / alpha-olefin solution co-polymerization reactions under the assistance of an activating co-catalyst, has extremely good polymerization activity and copolymerization performance, and can be used to prepare high molecular weight ethylene / alpha-olefin random copolymer with a high alpha-olefin content.

The invention relates to the field of microorganisms, and in particular to lactobacillus salivarius LS97 and an application thereof. The strain is preserved in the China General Microbiological Culture Collection Center on Dec.10, 2018, and the preservation number of the strain is CGMCC NO.16922. The strain is classified and named as Lactobacillus salivarius, and the preservation address of the strain is Institute of Microbiology, Chinese Academy of Sciences on No.3, No.1 Courtyard, Beichen West Road, Chaoyang District, Beijing. The lactobacillus salivarius LS97 can effectively inhibit growthof streptococcus sobrinus.