67results about How to "Good vulcanization" patented technology

The invention relates to ethylene propylene diene monomer and a preparation method thereof. The ethylene propylene diene monomer comprises 30 to 70%(mol) of ethylene. A third monomer is a liquid low-molecular weight copolymer obtained by copolymerization of cyclopentene and dicyclopentadiene. The ethylene propylene diene monomer comprises 0.5 to 12%(mol) of the third monomer. The third monomer liquid low-molecular weight copolymer of cyclopentene and dicyclopentadiene is a liquid low-molecular weight copolymer containing different double bond structures and having different double bond contents and comprises 3 to 30%(wt) of dicyclopentadiene. The preparation method of the liquid low-molecular weight copolymer has simple processes and a low cost. The liquid low-molecular weight copolymer has no pollution on the environment, an adjustable molecular weight and good dissolvability in a hydrocarbon solvent. The ethylene propylene diene monomer obtained by the preparation method has good sulfuration performances, can be sulfurated by sulphur, has a sulfuration rate close to a sulfuration rate of butadiene styrene rubber, and has good processing performances. The ethylene propylene diene monomer can be widely used for automobile parts, building materials, wires and cables, heat-resistant rubber pipes, high-grade seal pipes and polyolefin modification.

The invention provides a preparation method of alkali-proof vulcanized fluororubber. The preparation method includes steps of (1), adding water, emulsifiers and pH (potential of hydrogen) modifiers in a reactor; (2), adding polymerized monomers; (3), starting a stirring device, increasing temperature to be 70-120 DEG C, and adding initiators and chain transfer agents so as to start polymerization reaction; (4), adding residual polymerized monomers in batches, and stopping reaction after all the polymerized monomers are added so as to obtain polymerized emulsion; (5), coagulating, washing and drying the polymerized emulsion to obtain fluororubber; and (6), vulcanizing the fluororubber obtained in the step (5) so as to obtain the vulcanized fluororubber. The preparation method is simple in operation and requires mild reaction conditions. The structure of the fluororubber is controlled effectively by means of regulating structures of the monomers, changing reaction temperatures and the like, so that peroxide, namely the alkali-proof vulcanized fluororubber, is prepared. The prepared vulcanized fluororubber with high Mooney viscosity also has good curability and good oil resistance and can be applied to various industrial fields.

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.

The invention relates to a synthetic method for fluororubber. According to the invention, polymeric monomers comprise, by molar weight, 45 to 70% of vinylidene fluoride, 30 to 55% of hexafluoropropene and 0 to 20% of tetrafluoroethene, and are polymerized by using an intermittent emulsion polymerization method, and obtained polymerized emulsion is subjected to coacervation, rinsing, drying and plastication molding so as to obtain the fluororubber. The synthetic method provided in the invention is simple to operate, needs mild reaction conditions, effectively controls a Mooney point of the fluororubber through the measures of adjusting the structure of the monomers, changing reaction temperature, changing addition time of a chain transferring agent, etc., and prepares the fluororubber with a high Mooney point; the prepared fluororubber with a high Mooney point has good curability and excellent oil resistance and can be applied in a plurality of industries, especially in the industry of automobiles.

The invention provides a preparation method of an EPDM (Ethylene-Propylene-Diene Monomer) rubber. The method comprises the steps of polymerizing an ethylene, a propylene and a third monomer in an organic solvent under the action of a catalyst system to obtain the EPDM rubber. The third monomer is polybutadiene rubber with the content of over 9% of 1, 2-polybutadiene or polyisoprene rubber with the content of over 9% of 3, 4-polyisoprene, and the weight-average molecular weight of the third monomer is 200000-1000000; The catalyst system comprises a vanadium catalyst, an alkyl aluminum compound and an activation promoter. The obtained EPDM rubber has appropriate double bonds, so that sulfonation of the rubber can be carried out by using sulfur, and the EPDM rubber has good vulcanizing property and good processability. The experimental result shows that in the prepared EPDM rubber, the mole percentage of the double bond is 2%-10.5%, and the molecular weight distribution index is 2-5.

The invention provides a method for preparing rubber vulcanization accelerator zinc dimethyl dithiocarbamate (PZ), wherein the raw materials used are dimethylamine, carbon disulfide, nonionic surfactant and zinc oxide, and the stoichiometric ratio is two Methylamine: carbon disulfide: non-ionic surfactant: zinc oxide=1: 0.95-1.25: 0.02-0.025: 0.52-0.58; the concrete process of the inventive method is: in the reactor that fills pure water, under stirring state successively Add specified amount of dimethylamine, non-ionic surfactant, zinc oxide, stir for 30-50min, then add carbon disulfide liquid dropwise, dropwise time is 2-2.5h, temperature is controlled at 20°C-25°C; then stir for 1 hour, Carry out solid-liquid separation, discard the liquid, dry the solid, crush, sieve, and pack.

The invention provides a method for preparing zinc dibenzyl dithiocarbamate (ZBDC) thiofide, which comprises that: the raw materials used are dibenzylamine, carbon disulfide, sodium hydroxide and anionic surfactant, wherein the stoichiometric molar ratio of dibenzylamine to carbon disulfide to sodium hydroxide and anionic surfactant to zinc chloride to sulfuric acid is 1:1.05-1.2:1.05-1.2:0.020-0.025:0.53-0.58:0.005-0.015; and the process comprises: adding dibenzylamine, carbon disulfide, sodium hydroxide and anionic surfactant in a given amount into a reaction kettle holding purified water with stirring in turn, lower the temperature by 10 to 20 DEG C totally, dripping carbon disulfide liquid in a given amount within 6 to 7 hours, stirring for 0.5 to 1 hours after the dripping is finished, keeping the temperature at 30 to 38 DEG C constantly, dripping solution of zinc chloride, performing replacement reaction, regulating the pH value of the reaction liquid to 7 to 9 with sulfuric acid after the replacement reaction is finished, finishing the reaction, stirring for 1 to 2 hours, performing solid-liquid separation, discarding liquid and drying, crushing, sieving and packaging the solid. The anionic surfactant is sodium dodecyl sulfate.

A method to enhance drying efficiency of natural rubber, which is, in the process of acid coagulated natural rubber and micro-organism coagulated natural rubber, adding nanometer silicon dioxide suspension, coagulating, drying. A plurality of polar ''aqueous channel'' is formed in hydrophobic natural rubber, which can enhance quality of natural rubber. Drying efficiency of the inventive natural rubber is improved by about 20%, energy consumption is reduced by about 20%. The obtained natural rubber is in golden color and very dry. The quality thereof meets quality criterion of fifth Chinese standard natural rubber, with initial drawability P0 between 35 and 42, plasticity retention PR1 equal to or more than 75, content of nitrogen equal to or less than 0.54%, content of volatile equal to or less than 0.70%, content of ash equal to or less than 0.54%, Mooney viscosity of raw rubber between 75 and 79. The product has good vulcanizing property, and vulcanization thereof has good physical properties, high mechanical strength, great tear resistance.

The invention relates to a synthesis method of a low temperature-resistant perfluoroether rubber. The synthesis method comprises the following steps: 1) evenly mixing an emulsifier, fluoroether oil and water together and heating until 40 DEG C to form a microemulsion, and adding a comonomer A and a comonomer B to the microemulsion to obtain a mixed liquor; 2) adding deionized water and a pH regulator to a reaction kettle, adjusting the content of oxygen in the reaction kettle to be lower than 20ppm, increasing the temperature in the reaction kettle to the range of 70-120 DEG C, and adding the mixture of tetrafluoroethylene and perfluoromethyl vinyl ether to the reaction kettle; 3) adding the mixed liquor to the reaction kettle and adding the initiator potassium peroxodisulfate to start reacting, and adding a vulcanization point monomer and a chain transfer agent until the reaction ends, thereby obtaining a polymer; 4) performing electrolyte coagulation on the polymer and then washing, drying in vacuum and molding by plastifying to obtain the perfluoroether rubber. The synthesis method is simple to operate and mild in reaction conditions, and is capable of preparing the low-temperature-resistant perfluoroether rubber by adjusting the monomer structure.

The invention discloses a high-performance fluorine rubber gasket. The high-performance fluorine rubber gasket comprises, by weight, 40-80 parts of binary fluorine rubber, 20-30 parts of silane-modified fluororubber, 12-20 parts of atomized carbon black, 5-10 parts of barium sulfate, 5-15 parts of calcium hydroxide, 1-5 parts of calcium titanate, 1-3 parts of chelate titanate coupling agents, 2-6 parts of molybdenum disulfide, 2-6 parts of phenyl methylpolysilicone resin, 1-2 parts of magnesium oxide, 1-3 parts of dicumyl peroxide, 0.5-1.2 parts of dibenzothiazyl disulfide, 0.5-1.2 parts of triallyl isocyanurate, 1-1.8 parts of bisphenol A, 1-3 parts of hexafluoride isopropylidene diphenol, 1-3 parts of benzyl triphenyl phosphoric chloride, 1-2 parts of sodium stearate, 1-3 parts of palm wax, 1-3 parts of fluorinated polyamide and 1-2 parts of fatty alcohol. The invention further discloses a manufacturing method of the high-performance fluorine rubber gasket. The compression deformation and high-temperature steam resistance of the fluorine rubber gasket are excellent, and the manufacturing method is simple.

The invention discloses an anti-aging modified natural rubber composite material. The anti-aging modified natural rubber composite material is prepared from natural rubber, butadiene rubber, butadiene styrene rubber, butadiene-acrylonitrile rubber, epoxidized natural rubber, nano-zinc oxide, stearic acid, sulfur, dicumyl peroxide, triallyl trimellitate, p-tert-butyl-phenolic resin, nano calcium carbonate, precipitated silica, carbon black purple, nano-microcrystalline cellulose, nano-silicon dioxide, an anti-aging agent, potassium iso-propyl xanthate, dibenzylamine, tetrahydrofurfurylamine, isopropyl trioleoyl titanate, vinyltris(beta-methoxyethoxy)silane, diethylene glycol distearate and polyethyl dialcohol adipate. The anti-aging modified natural rubber composite material is high in strength, good in heat resistance and aging resistance and capable of meeting the usage requirements of multiple fields of cables, rubber pipes and the like.

The invention relates to a rapidly vulcanized fluoroelastomer and a preparation method thereof. The rapidly vulcanized fluoroelastomer comprises comonomers. The comonomers comprise two or more of vinylidene fluoride, chlorotrifluoroethylene, tetrafluoroethylene, 3, 3, 3-trifluoropropene, hexafluoropropylene and a perfluoroalkyl ether monomer, and a vulcanization point monomer, wherein a use amount of the vulcanization point monomer is 2-3% that of the comonomers. The rapidly vulcanized fluoroelastomer has high fuel permeability resistance, short vulcanization time, a fast vulcanization rate, low Mooney viscosity and high mechanical properties. The preparation method controls vulcanization time tc90 of the fluoroelastomer within 80s. The rapidly vulcanized fluoroelastomer has Mooney viscosity [ML(1+10 121 DEG C)] of 50-80 DEG C, tensile strength of greater than or equal to 22MPa and elongation of greater than or equal to 230%.

The invention discloses a fluorubber use bisphenol AF pre-dispersion mother colloidal particle formula prepared from the following raw materials by mass: 30-70 parts of bisphenol AF; 35-55 parts of fluorubber; 0.1-10 parts of a dispersant; 0.1-10 parts of a release agent; and 0-1 parts of a colorant. The fluorubber as a carrier is cooperated with the dispersant and the release agent, the bisphenol AF curing agent is mixed into the fluorubber on an open blending machine, so that the bisphenol AF is fully dispersed uniformly in the fluorubber, the bisphenol AF curing agent has excellent curing properties in the fluorubber, and can meet the use requirements. The fluorubber use bisphenol AF pre-dispersion mother colloidal particle formula can improve the dispersion of the fluorubber curing agent bisphenol AF (2, 2-bis-(4-hydroxy phenyl) hexafluoropropane) and BPP (tri phenyl phosphorus chloride) in the fluorubber, and overcomes the problems of the poor dispersion and mutual smelting of a traditional curing agent in the fluorubber.

The invention relates to peroxide vulcanized fluororubber and a polymerizing method thereof. The polymerizing method comprises the following steps: (1) mixing an emulsifier, hydrofluoroether oil and water and heating to form colorless and transparent microemulsion; (2) adding water and a pH regulator into a reactor until system pH is 8 to 9, firstly utilizing nitrogen to displace air in the reactor, and then introducing mixed gas to displace nitrogen; (3) adding the microemulsion into the reactor, continuing introducing mixed monomer, adding an initiator and a chain transfer agent and starting polymerization reaction; (4) adding a vulcanization point monomer to react continuously when the mixed monomer reacts and reaches certain accumulative reacting weight; (5) agglomerating, washing and drying obtained polymerized emulsion, plastifying and shaping, and packaging to obtain the fluororubber. The polymerizing method disclosed by the invention improves a reaction rate by improving a configuring mode of the emulsifier, adjusting adding time and an adding mode of the vulcanization point monomer and the like, and improves vulcanizing performance of the peroxide vulcanized fluororubber.

The invention relates to a preparation method of tetrabutylthiuram disulfide used as a rubber vulcanization accelerator. By virtue of the preparation method, tetrabutylthiuram disulfide is prepared by a two-step process, namely sodium dibenzyl amino sulfonate is prepared from dibenzylamine, carbon disulfide and sodium hydroxide and then oxidized by a hydrogen peroxide oxidant to prepare tetrabutylthiuram disulfide. According to the preparation method, carbon disulfide is excessive, so that dibenzylamine is fully reacted; excessive unreacted carbon disulfide is separated and recycled in time; the production cost is reduced; the pollution to the environment is low; low-concentration hydrogen peroxide with a concentration of 5-20wt% is used as the oxidant and applied to the oxidation reaction; hydrogen peroxide has the characteristics of being low in cost, stable in property, small in pollution, easy to store and transport and high in safety; the cost can be effectively reduced; the pollution to workers in the operation process is alleviated; the safety is improved; meanwhile, the oxidization effect is not reduced.

The invention relates to a single-ingredient silicone structural sealant and a preparation method thereof. The single-ingredient silicone structural sealant is prepared from 100 parts of poly-alkylsiloxane, 70 to 150 parts of inorganic filling materials, 3 to 10 parts of composite silane cross linking agents, 1 to 5 parts of composite silane coupling agents, 1 to 5 parts of titanium ester catalysts and 0.1 to 0.5 part of organic tin catalysts. The single-ingredient silicone structural sealant uses a mode of adding the composite silane cross linking agents into the composite silane coupling agents on the basis of using the poly-alkylsiloxane as a main body raw material; by using a mode of improving the Van der Waals' force and the hydrogen-bond interaction on the polarity base material by polarity functional groups on longer polarity long chains in the composite silane coupling agents, the bonding force on the substrates can be further enhanced; on the basis, through the existence of the polarity chain sections, the reinforcing effect of the filling materials can be improved, and the cohesion of the structural sealant is improved; meanwhile, the effect of optimizing the cross linking structure can be achieved by the composite silane cross linking agents; therefore the stretch intensity of the structural sealant is improved.

The invention discloses a vulcanized mould for a secondary-class building seismic isolation support. The mould comprises an upper mould, a lower mould, two molding blocks, rubber discharging blocks, hoisting blocks and a mandrel, wherein the hoisting blocks are arranged surrounding the outer parts of the upper mould and the lower mould; the upper mould and the lower mould are connected through the molding blocks; the two molding blocks are connected through a bolt rod; the rubber discharging blocks are arranged on the upper mould and the lower mould; and the two ends of the mandrel are respectively connected with the rubber discharging block of the upper mould and the rubber discharging block of the lower mould. The mould has a simple structure, is reasonable in design, is simple and convenient to operate, has good vulcanizing property, has good integrity and use security, is attractive in appearance, is convenient to separate and replace, costs less time and saves materials; the mould is high in repeating utilization ratio, low in using cost, and long in service life; and the manufactured support has higher quality and can meet production demands of people.

The invention relates to a method for preparing zinc diphenyl dithiocarbamate, belonging to the technical field of chemical synthesis. The method comprises the steps of: firstly, reacting carbon disulfide with diphenylamine under the condition that water is used as solvent and sodium hydroxide is used as a catalyst, and then carrying out replacement reaction with zinc chloride. The synthesis can be finished in two steps in the reaction process and is free of complicated processing processes, three wastes are not generated basically, and products have high purity and good color. The invention has the advantages that the sodium hydroxide is cheap and common and is easy to purchase, the method has short production cycle and high safety coefficient, basically no waste gas is discharged, the products have high melting point and white appearance, the total product yield is 80-92% and the comprehensive cost is low.