35 results about "P-dichlorobenzene" patented technology

The invention relates to a synthesis process of p-chlorophenylboronic acid, which comprises the following steps: by taking tetrahydrofuran as a solvent and p-dichlorobenzene as an initial raw material, firstly preparing p-chlorophenylmagnesium chloride through Grignard reaction, then reacting the p-chlorophenylmagnesium chloride with boric acid ester in a microchannel reactor to obtain a p-chlorophenylboronic acid ester crude product, and then hydrolyzing, layering and carrying out oil-phase azeotropic distillation to obtain the p-chlorophenylboronic acid ester. And finally, recrystallizing by adopting a mixed system of an alcohol solvent and a benzene solvent to obtain p-chlorophenylboronic acid with the content of 98% or above. The synthetic process of the p-chlorophenylboronic acid is mild in reaction condition, simple and convenient to operate, low in cost, high in safety, high in product content and very suitable for being applied to industrial large-scale production.

The invention relates to the technical field of high polymer materials, and discloses a synthesis method of low-chlorine polyphenylene sulfide nitrile, which comprises the following steps: carrying out pressurized prepolymerization reaction on a sodium sulfide solution and p-dichlorobenzene to obtain a first prepolymerization reaction product; carrying out copolymerization prepolymerization reaction on the first prepolymerization reaction product and 2, 6-dichlorobenzonitrile to obtain a second prepolymerization reaction product; carrying out heating polymerization reaction on the second prepolymerization reaction product and benzyl chloride to obtain a heating polymerization reaction product; and raising the temperature of the polymerization reaction product, and carrying out phase separation to obtain the low-chlorine polyphenylene sulfide nitrile. Under the condition of no auxiliary agent, the polymerization process of inert gas pressurization and phase separation is adopted, benzyl chloride is applied to adjust the end group, low-chlorine high-molecular-weight polyphenylene sulfide nitrile can be obtained in a short time, the production efficiency of synthesizing polyphenylene sulfide nitrile can be improved, the purification process of byproduct sodium chloride is shortened, auxiliary agent recovery is omitted, and the production cost is reduced. The engineering construction investment is reduced, and the production cost for manufacturing the polyphenylene sulfide nitrile is greatly reduced.

The invention is suitable for the technical field of chemical purification, and provides a high-purity 2, 4-dichlorobenzonitrile preparation method, which comprises: carrying out cooling crystallization treatment on a 2, 4-dichlorobenzonitrile liquid crude product at a cooling rate of 0.5-5 DEG C / h and a cooling end point of 50-53 DEG C, and carrying out heat preservation for 1-1.5 h; and performing heating sweating treatment on the crystal obtained by the cooling crystallization treatment at a heating rate of 0.5-3 DEG C / h, heating to 57-61 DEG C, and keeping the temperature for 0.5-1 h. According to the method, the high-purity 2, 4-dichlorobenzonitrile product with the purity being greater than or equal to 99.5% can be obtained, no additional solvent is needed, no other three-waste treatment is needed, the product purity is high, and the method is a green separation and purification process; in addition, the preparation process is simple and efficient, the investment of melt crystallization equipment is low, the operation condition is mild, the risk is low, the production safety coefficient is high, the total yield of purification is high after coupling with an upstream rectification process, and the method is suitable for industrial production.

The invention belongs to the field of high polymer material synthesis, and provides a method for preparing polyphenylene sulfide from high-purity p-dichlorobenzene, which adopts the whole process design of pre-construction of a composite sulfur source intermediate, regulation and control of an end group controllable oligomerization polyphenylene sulfide intermediate, segmented polymerization of the high-purity p-dichlorobenzene and precise dehydration-washing-drying. The ultra-low impurity level of 0.05-0.25 wt% of burning residues of the polyphenylene sulfide product, the sodium ion content of 10-200 mg / kg and the chloride ion content of 10-500 mg / kg is achieved, and meanwhile the high-performance stability of the melting point of 270-300 DEG C, the gel fraction of 92-99 wt% and the water content of 0.01-0.20 wt% is kept. The problems of deep removal of inorganic ions and ash content, balance of gel fraction and processability and control of residual solvents in the traditional polyphenylene sulfide preparation process are solved, and the method has wide application value in the fields of high-performance engineering plastics, special fibers, electronic packaging materials and the like.

The utility model discloses a condenser for dichlorobenzene separation. The condenser comprises a condensing shell and a cleaning mechanism, partition plates are arranged at the upper end and the lower end in the condensation shell respectively, condensation pipes which are evenly distributed are arranged between the partition plates in a penetrating mode, a steam pipe and a liquid outlet pipe are arranged on the side wall of the condensation shell in a penetrating mode respectively, a gathering tank is arranged at the right end of the liquid outlet pipe through a connecting pipe, a leading-out pipe is arranged on the bottom wall of the gathering tank in a penetrating mode, and a cold water pipe is arranged on the top wall of the condensation shell in a penetrating mode. A water outlet pipe penetrates through the bottom wall of the condensation shell; the cleaning mechanism is arranged in the condensation shell, the cleaning mechanism and the condensation pipe are installed in a matched mode, according to the condenser for dichlorobenzene separation, the pressure in the device is balanced by adjusting the pressure of liquefied and separated dichlorobenzene, and therefore the liquefied and separated dichlorobenzene can conveniently flow out by overcoming the negative pressure; and meanwhile, the device can automatically clean impurities adhered to the surface of a condensation part, so that the condensation, liquefaction and separation efficiency of dichlorobenzene is prevented from being influenced.

The invention belongs to the technical field of chromosome karyotype analysis, and particularly discloses a bougainvillea speetabilis karyotype chromosome number identification method which comprises the following steps: S1, putting a root tip of bougainvillea speetabilis into a mixed solution containing a saturated p-dichlorobenzene solution, 5-20 [mu] L of alpha-bromonaphthalene and 0.008% 15-30 [mu] L of cyclohexaneimide for pretreatment; s2, the root tips are placed in paraformaldehyde fixing liquid to be fixed; s3, after the root tips are cleaned, the root tips are put into an HCl solution; s4, the root tips obtained in the step S3 are placed in a 0.075 mol / L KCl solution to be soaked; s5, dyeing; and S6, carrying out microscopic examination and photographing. The invention also provides an identification system for the bougainvillea glabra karyotype chromosome number. By adopting the identification method and system provided by the invention for identification, chromosomes of bougainvillea speetabilis are dispersed without overlapping, distortion, fracture and main singular marks, and bougainvillea speetabilis chromosome karyotype analysis is facilitated.

The invention relates to the technical field of polyphenylene sulfide, in particular to low-molecular-weight polyphenylene sulfide and a preparation method thereof.The preparation method of the low-molecular-weight polyphenylene sulfide comprises the steps that sodium hydroxide, sodium acetate and sodium hydrosulfide with the required amount are sequentially put into a reaction kettle, then N-methyl pyrrolidone is added, heating dehydration is conducted under nitrogen protection, and a mixed solution is obtained; adding preheated paradichlorobenzene into the mixed solution, adding part of an end-capping reagent at the required polymerization temperature under the protection of nitrogen, and carrying out prepolymerization stage reaction; and after the pre-polymerization stage is finished, carrying out temperature programming on the reaction kettle, adding the residual end-capping reagent, and carrying out polymerization stage reaction to obtain the low-molecular-weight polyphenylene sulfide. According to the invention, a specific amount of the end-capping reagent is added in the stages of prepolymerization and polymerization reaction, so that the chain growth of the polymerization reaction of the polyphenylene sulfide is actively terminated, and the low-molecular-weight polyphenylene sulfide with the molecular weight of less than 8000, narrower molecular weight distribution and good melting and viscosity properties is prepared.

The invention belongs to the technical field of high polymer material synthesis, and particularly discloses super-tough polyphenylene sulfide resin and a preparation method and application thereof.The method comprises the following steps that sodium sulfide and a sodium hydroxide solution are heated and mixed in the nitrogen atmosphere; raising the temperature again, performing decompression dehydration, and adding N-methyl pyrrolidone; adding p-dichlorobenzene and a catalyst for reaction; cooling, and carrying out solid-liquid separation on the polymer mixed slurry to obtain a solid material; and drying the solid material in vacuum. According to the super-tough polyphenylene sulfide resin as well as the preparation method and the application thereof, the super-tough polyphenylene sulfide resin with high molecular weight and low molecular weight distribution can be directly prepared at a synthesis end, and a low-temperature-freezing-resistant super-tough polyphenylene sulfide resin composite material can be obtained through the super-tough polyphenylene sulfide resin; and therefore, the application in multiple fields such as cooling systems of new energy automobiles and water peripheries of household appliances is realized.

This invention belongs to the field of catalyst technology, specifically relating to a supported iron-ruthenium catalyst and its application in the synthesis of m-dichlorobenzene and / or para-dichlorobenzene. The iron-ruthenium catalyst comprises a support and iron and ruthenium supported on the support. The support comprises quaternary ammonium salt-modified diatomaceous earth. Based on the total weight of the catalyst, the mass percentage of iron is 5-15%, and the mass percentage of ruthenium is 3-9%. The abundant active sites on the surface of the quaternary ammonium salt-modified diatomaceous earth support can significantly improve the catalytic activity and selectivity for m-dichlorobenzene and / or para-dichlorobenzene, without the formation of trichlorobenzene. The catalyst lifetime is 5-8 times longer than that of iron catalysts. The product can be separated and purified by stripping, distillation, and crystallization. The process is simple and can obtain high-purity m-dichlorobenzene and para-dichlorobenzene products.

The invention relates to the technical field of p-dichlorobenzene production, and discloses a feeding device for p-dichlorobenzene production, which comprises a barrel body, a liquid inlet pipe, a liquid outlet pipe, a liquid outlet pipe and a liquid outlet pipe, the air inlet pipe is communicated with the top of the barrel body; and the feeding assembly is arranged at the top of the barrel body, the feeding assembly is further connected with the rotating rod, and the feeding assembly is used for enabling the catalyst to uniformly enter the barrel body step by step. According to the device, benzene liquid, chlorine and a catalyst can intermittently and uniformly enter the barrel body for mixing in batches, the situation that all raw materials are added at a time to cause uneven mixing is avoided, the benzene liquid, the chlorine and the catalyst in the barrel body can be automatically stirred and mixed, the reaction uniformity is ensured in the stirring process, and the reaction efficiency is improved. And the reaction efficiency is improved, so that the use effect of the equipment is improved.

This invention relates to a bacterium that degrades chlorobenzene pollutants and its applications. The bacterium is a *Pseudomonas putida* strain, named *Pseudomonas putida* BS-1, deposited at the China Center for Type Culture Collection (CCTCC) with accession number CCTCC M 2024441 on March 11, 2024. Compared with existing technologies, the strain provided by this invention can completely degrade a complex pollutant mixture of dichlorobenzene, chlorobenzene, and benzene within 48 hours. It can survive for a long time and maintain its degradation activity under actual pollution conditions of complex pollution and low temperatures. Furthermore, the functional genes related to the degradation of chlorobenzene pollutants are located on a plasmid, which helps the indigenous bacterium acquire the relevant functions for degrading chlorobenzene pollutants. This strain can be applied to in-situ bioremediation of groundwater with complex chlorobenzene pollution in chemical industrial parks, effectively overcoming the technical shortcomings of traditional reduction dechlorination remediation technologies, which often result in incomplete reduction of products, and achieving green, sustainable, and thorough purification without secondary pollutants.

The present invention provides a method for separating mixed dichlorobenzenes. The method comprises: (a) contacting the mixed dichlorobenzenes with extractant A in an extractive distillation column for extractive distillation separation to obtain crude p-dichlorobenzene from the top of the extractive distillation column; (b) feeding the bottom material of the extractive distillation column and solvent B into a crystallization and precipitation unit to obtain crystals mainly composed of m-dichlorobenzene and o-dichlorobenzene, as well as a solvent phase of extractant A and solvent B; (c) heating the crystals mainly composed of m-dichlorobenzene and o-dichlorobenzene and feeding them into a rectification column for rectification separation, separating out the crude product containing solvent B from the top of the rectification column, and taking out the crude m-dichlorobenzene from the side line and the crude o-dichlorobenzene from the bottom of the column. The method of the present invention includes using extractive distillation technology, crystallization technology and rectification technology to separate the mixed dichlorobenzenes containing o-dichlorobenzene, m-dichlorobenzene and p-dichlorobenzene, and finally obtaining high-purity o-, m- and p-dichlorobenzene products.

The invention discloses a preparation method of an anaerobic microbial agent for stably degrading 1, 4-dichlorobenzene. The method comprises the following steps: collecting 1, 4-dichlorobenzene polluted site soil and in-situ underground water, constructing a sealed anaerobic microcosm in an anaerobic glove box according to 30 g of soil and 170 mL of underground water, and culturing in a dark place; 1, 4-dichlorobenzene is used as a directional selection substrate, and an electron donor (preferably methanol) capable of anaerobic hydrogen production is added according to 10 times of electron equivalent relative to the 1, 4-dichlorobenzene. In the first round, 5.15-10.3 mg / L is added, if complete degradation or residue is smaller than or equal to 3% of the initial round, the next round is supplemented, the amount of the added liquid is increased by 5.15-10.3 mg / L in each round, the amount of the added liquid is smaller than or equal to 58.5 mg / L in a single round, and circulation is larger than or equal to 10 rounds; and 10 mL of the enriched bacterial liquid can be transferred to 190 mL of a mineral culture medium for passage amplification. The obtained microbial inoculum can tolerate 1, 4-dichlorobenzene with relatively high concentration, is stable in degradation, and can be used for anaerobic bioremediation of polluted soil and underground water.

This invention belongs to the field of resin preparation technology, specifically relating to a polyphenylene sulfide resin and its preparation method. The preparation method includes the following steps: a composite stabilizer, anhydrous sodium sulfide, and a polar solvent are first mixed; the resulting first mixture undergoes a dehydration reaction to obtain a dehydrated reaction solution; the dehydrated reaction solution is then mixed with p-dichlorobenzene; the resulting second mixture undergoes prepolymerization and postpolymerization sequentially to obtain the polyphenylene sulfide resin; the composite stabilizer includes carbodiimide having the structure of formula I, lithium chloride, and sodium hydroxide; R 1 -(N=C=N) n -R 2 Equation I; n is an integer from 1 to 20; R 1 and R 2 The polymer is independently selected from substituted or unsubstituted alkyl, cycloalkyl, aryl, or aralkyl groups. The composite stabilizer in this invention effectively inhibits excessive hydrolysis by polar solvents, improves reaction efficiency, and controls the polymer molecular structure, thereby obtaining high molecular weight, high yield, and high whiteness PPS resin.

The invention belongs to the technical field of resin gears, and particularly provides a low-friction compound gear as well as a preparation method and application thereof.The low-friction compound gear is prepared by mixing the following raw materials in parts by mass: 50-60 parts of polylaurolactam, 15-20 parts of polyformaldehyde, 2-3 parts of a compatilizer, 2-3 parts of heat conduction fibers, 0.3-0.4 part of a coupling agent, 0.1-0.2 part of a crystal forming agent and 0.01-0.02 part of an antioxidant; the heat-conducting fibers are obtained by etching polyether-ether-ketone fibers and coating and curing the polyether-ether-ketone fibers; the crystal forming agent is obtained by condensation polymerization of p-dichlorobenzene, sodium sulfide and biphenyl derivatives. According to the compound gear prepared by matching the crystal forming agent with the heat-conducting fiber, the crystallinity of the gear product can reach 67.9%, the heat conductivity is greater than or equal to 3.34 W. (m.K)-1, and the mechanical property is excellent.

The invention discloses a carbon material doped polyphenylene sulfide composite material and a preparation method thereof. The carbon material doped polyphenylene sulfide composite material comprises the following raw materials in parts by weight: 100 parts of alkali metal hydrosulfide, 90-110 parts of p-dichlorobenzene, 500-700 parts of N-methyl pyrrolidone, 90-120 parts of alkali metal hydroxide, 20-60 parts of alkali metal weak acid salt and 0.3-1.2 parts of a carbon material. According to the carbon material doped polyphenylene sulfide composite material and the preparation method thereof disclosed by the invention, the carbon material doped polyphenylene sulfide composite material is prepared, and the carbon material and a PPS matrix form chemical bonding in a polymerization process, so that the interface bonding strength is remarkably enhanced, the dispersity of the carbon material in a system is improved, and the carbon material doped polyphenylene sulfide composite material is prepared. The problem of performance reduction caused by weak interface bonding in a traditional physical mixing method is solved, and meanwhile, the electrical conductivity, the thermal conductivity and the mechanical performance of the material are comprehensively optimized.

The invention relates to a preparation method of 4 '-chloro-2-aminobiphenyl, and relates to the technical field of organic synthesis.The preparation method comprises the following steps that p-dichlorobenzene, a sulfur trioxide-pyridine compound and thionyl chloride are subjected to a reaction, and 2, 5-dichlorobenzene sulfonyl chloride is obtained; the preparation method comprises the following steps: reacting 2, 5-dichlorobenzenesulfonyl chloride, aniline hydrochloride and a sodium bicarbonate solution to obtain 2, 5-dichloro-N-phenylbenzenesulfonamide; the preparation method comprises the following steps: reacting 2, 5-dichloro-N-phenylbenzenesulfonamide, cysteine, a titanium dioxide nanotube and a hydrogen peroxide solution to obtain 2-chloro-6H-dibenzothiazine dioxide; the preparation method comprises the following steps: reacting 2-chloro-6H-dibenzothiazine dioxide, zinc powder and glacial acetic acid to obtain an intermediate; and mixing the intermediate, p-toluenesulfonic acid and a solvent, and carrying out microwave-assisted hydrolysis to obtain 4 '-chloro-2-aminobiphenyl. The method has the effects of improving the yield and purity of the product, and meanwhile, the environmental protection property and economical efficiency of the process are improved.

The present application discloses a method for synthesizing 2,4-difluoronitrobenzene and 2-fluoro-5-chloronitrobenzene, which belongs to the technical field of organic chemical industry. 2,5-dichloronitrobenzene is used as a raw material to generate 2,4-difluoronitrobenzene and 2-fluoro-5-chloronitrobenzene. 2-Fluoro-4-chloronitrobenzene and potassium fluoride are reacted with a phase transfer catalyst and 2-fluoro-5-chloronitrobenzene as a solvent to obtain 2,4-difluoronitrobenzene and 2-fluoro-5-chloronitrobenzene. Starting from 2,5-dichloronitrobenzene obtained by nitrating inexpensive p-dichlorobenzene, a synthetic route is found that can synthesize high-value-added 2,4-difluoronitrobenzene at low cost and can also improve the selectivity of fluorination of 2,5-dichloronitrobenzene. The method improves the selectivity of the fluorination reaction of 2,5-dichloronitrobenzene and reduces the production cost of 2,4-difluoronitrobenzene.

The invention discloses a preparation method of antioxidant polyphenylene sulfide resin, and aims to solve the problems of metal catalytic oxidation, easy loss of antioxidant due to uneven dispersion and poor high-temperature stability in the prior art. The preparation method comprises the following steps: pre-polymerizing p-dichlorobenzene, sodium sulfide, N-methyl pyrrolidone and a catalyst to obtain oligomer slurry; after cooling, adding a composite antioxidant system for dispersion, and then adding a dispersing aid containing a siloxane chain segment; raising the temperature to 230-250 DEG C for final polymerization, and washing and drying to obtain a product. The composite antioxidant system can block multi-path oxidation, and the dispersing aid can reduce the loss of the antioxidant. The oxidation induction temperature of the product is 490-470 DEG C, the tensile strength retention rate is greater than or equal to 92% after the product is aged for 1200 hours at 230 DEG C, the loss rate of the antioxidant is less than or equal to 5%, and the process is suitable for industrialization and is suitable for harsh scenes such as high-temperature filtration and automotive electronics.

The present disclosure discloses a method for preparing high-activity polyphenylene sulfide (PPS) by regulating and controlling a water content in a polymerization process and a high-efficiency polyphenylene sulfide resin prepared thereby. The preparation method includes: carrying out a polycondensation reaction with sodium hydrosulfide and p-dichlorobenzene as raw materials and N-methyl-2-pyrrolidone as a solvent until a conversion rate of the p-dichlorobenzene reaches 97% or above, adding deionized water, reducing the temperature in a reactor to 250-260° C. for heat preservation for 1-3 h, and performing cooling for post-treatment; and calculated with the sodium hydrosulfide as 1.0 mol, a molar amount of the added deionized water is 1.0-2.5 mol. The method for preparing high-activity polyphenylene sulfide disclosed in the present disclosure can be simultaneously realized in a PPS polymerization process, and that is to say, an end-capping reagent is not required to be additionally added to affect the molecular weight and thermal stability of the finally prepared PPS; and activation treatment is also not required to be performed after the PPS resin is prepared to additionally increase the technological process and the production cost.

The invention discloses a synthesis method of 2, 4-difluoronitrobenzene and 2-fluorine-5-chloronitrobenzene, and belongs to the technical field of organic chemical industry, 2, 5-dichloronitrobenzene is used as a raw material to generate 2, 4-difluoronitrobenzene and 2-fluorine-5-chloronitrobenzene, 2-fluorine-4-chloronitrobenzene and potassium fluoride are subjected to a reaction in the presence of a phase transfer catalyst and 2-fluorine-5-chloronitrobenzene as a solvent, and 2, 4-difluoronitrobenzene and 2-fluorine-5-chloronitrobenzene are subjected to post-treatment to obtain 2, 4-difluoronitrobenzene and 2-fluorine-5-chloronitrobenzene. The 2, 4-difluoronitrobenzene and the 2-fluorine-5-chloronitrobenzene are reacted to obtain 2, 4-difluoronitrobenzene According to the method, 2, 5-dichloronitrobenzene is obtained through nitration of cheap p-dichlorobenzene, and a route capable of synthesizing 2, 4-difluoronitrobenzene with a high additional value at low cost and a synthesis route capable of improving the fluoridation selectivity of 2, 5-dichloronitrobenzene are found; according to the method, the selectivity of the fluoridation reaction of the 2, 5-dichloronitrobenzene is improved, and the production cost of the 2, 4-difluoronitrobenzene is reduced.

The present invention relates to the technical field of electrical insulation materials, and specifically to an oil-resistant and hydrolysis-resistant electrical insulation composite material, a preparation method, and an application thereof. The composite material comprises a membrane material, a paper material adhered to both sides of the membrane material, and a glue for bonding. The membrane material is made of polyphenylene sulfide, and the pulp used to prepare the paper material comprises polyphenylene sulfide staple fibers, meta-aramid staple fibers, and meta-aramid precipitation slurry. The polyphenylene sulfide is prepared by polymerization of anhydrous sodium sulfide and dichlorobenzene, wherein the molar ratio of the anhydrous sodium sulfide to the dichlorobenzene is 1:(0.95-0.98). The dichlorobenzene comprises meta-dichlorobenzene and para-dichlorobenzene, and the molar ratio of the meta-dichlorobenzene to the para-dichlorobenzene is (3-4):1. The oil-resistant and hydrolysis-resistant electrical insulation composite material of the present invention has good mechanical and electrical properties, can meet the application requirements in motors, and the composite material has excellent insulation properties, while also having oil resistance and hydrolysis resistance.

The invention discloses low-end-group chlorine polyphenylene sulfide and a preparation method thereof.The preparation method comprises the following steps that N-methyl pyrrolidone, a sodium hydrosulfide aqueous solution, a hydroxide aqueous solution and a catalyst are mixed, and a mixture is obtained; removing free water in the mixture, adding N-methyl pyrrolidone and p-dichlorobenzene into the mixture under a nitrogen protection atmosphere, heating to 180-240 DEG C, carrying out an early polymerization reaction, heating to 240-270 DEG C, adding a third monomer, and carrying out a later polymerization reaction; and after the reaction is finished, cooling, filtering, washing and drying to obtain the low-end-group chlorine polyphenylene sulfide. Through an innovative synthesis process, the prepared PPS resin with low end group chlorine is uniform in particle shape, the product yield is in an industry leading level, and the problems that in a traditional process, the content of end group chlorine of a product is high, and the product gradually dissociates in the processing process are effectively solved; by means of excellent performance, the packaging film can be widely applied to high-end fields such as electronic component packaging and the like.

The invention discloses branched polyphenylene sulfide resin for aerospace and a preparation method of the branched polyphenylene sulfide resin, and belongs to the technical field of high polymer materials. The branched polyphenylene sulfide resin for aerospace comprises the following raw materials: sodium sulfide, sodium hydroxide, a catalyst, a solvent NMP, p-dichlorobenzene and a third monomer, the molar ratio of p-dichlorobenzene to sodium sulfide is 1: 1.05, the third monomer is one or a mixture of more of chlorine-terminated or sulfur-terminated third monomers, the addition amount of the third monomer is 0.01-5.0% of the total molar weight of the monomers, and the addition amount of the third monomer is 0.01-5.0% of the total molar weight of the monomers. The catalyst is added when the reaction time is 60-80% of the total reaction time and the temperature is 220-260 DEG C. By accurately regulating and controlling the type, the addition amount, the addition time and the reaction temperature of the third monomer, the branching structure is uniform and controllable, and the branching degree, the thermal deformation temperature, the mechanical property and the processability of the resin are remarkably improved; therefore, the high-performance branched polyphenylene sulfide resin suitable for engine parts, high-temperature-resistant structural members and electrical insulation systems in the aerospace field is prepared.

The invention belongs to the field of high polymer material synthesis, and particularly provides a preparation method of an antioxidant PPS melt-blown material.In the polymerization process, a naphthalene ring structure monomer is introduced to be subjected to condensation polymerization with p-dichlorobenzene and sodium hydrosulfide in a polar solvent, a PPS copolymer containing a naphthalene ring structure is formed, the oxidation resistance of the PPS copolymer can be improved through introduction of a naphthalene ring, and the antioxidant performance of the PPS melt-blown material is improved; the strength and the toughness of the material can also be enhanced; when the composite material is applied to preparation of the melt-blown material, the subsequent modification treatment of coating, dipping or adding an antioxidant on the surface of the melt-blown material can be reduced, the process is simplified, the production efficiency is improved, and the production cost of the melt-blown material is reduced.

The invention belongs to the field of chemical material treatment, and particularly relates to a solvent recovery method in a polyphenylene sulfide resin production process. According to the method, low polymers are cut firstly, then N-methyl pyrrolidone and p-dichlorobenzene in washing liquid are extracted and recovered, high-energy-consumption operation of direct water steaming is avoided, an extraction agent in a raffinate phase is recovered in a pervaporation mode, selective permeability of a membrane is utilized, and compared with steam stripping, the separation efficiency is high, the energy consumption is low, and the cost is low. The extraction agent is recovered in an azeotropic coupling steam stripping manner, so that on one hand, the energy consumption is reduced, and on the other hand, the problem of acidizing corrosion of a reboiler caused by heating rectification by using the reboiler is solved; the method comprises the following steps: carrying out reduced pressure supergravity rectification on residual components, recycling unreacted p-dichlorobenzene monomers, and then carrying out refining purification and other treatment operations on NMP, so that efficient recovery of the solvent NMP is realized, and the method has the characteristics of controllable process, high separation efficiency, low energy consumption, small pollution, high solvent purity and high yield.

The invention relates to the technical field of electrical insulation materials, in particular to an oil-resistant hydrolysis-resistant electrical insulation composite material and a preparation method and application thereof.The composite material comprises a membrane material, paper materials adhered to the two sides of the membrane material and glue playing a bonding role, paper pulp for preparing the paper material comprises polyphenylene sulfide staple fibers, meta-aramid staple fibers and meta-aramid precipitation pulp. The polyphenylene sulfide is prepared by polymerization reaction of anhydrous sodium sulfide and dichlorobenzene, the molar ratio of the anhydrous sodium sulfide to the dichlorobenzene is 1: (0.95-0.98), the dichlorobenzene comprises m-dichlorobenzene and p-dichlorobenzene, and the molar ratio of the m-dichlorobenzene to the p-dichlorobenzene is (3-4): 1. The oil-resistant and hydrolysis-resistant electrical insulation composite material disclosed by the invention has good mechanical properties and electrical properties, can meet the application requirements in a motor, has good insulation properties, and has oil-resistant and hydrolysis-resistant properties at the same time.

The present application belongs to the technical field of new plant variety breeding, and particularly relates to a breeding method of a bletilla triplod and application thereof. The breeding method of the bletilla triplod comprises the following steps: screening a bletilla diploid; artificially inducing and identifying a bletilla tetraploid; culturing the identified bletilla tetraploid to flowering; and hybridizing the bletilla tetraploid and the bletilla diploid to obtain a bletilla triplod fruit; wherein a mutagen used for the induction is a mixed aqueous solution of 10 ppm p-dichlorobenzene and 5 ppm alpha-bromonaphthalene. The present application first creates a new bletilla triplod variety, and establishes a complete set of bletilla triplod advantage utilization and breeding method. The present application first obtains a new bletilla triplod germplasm, and lays a scientific foundation for bletilla triplod breeding.

The application belongs to the technical field of resin gears, and specifically provides a low-friction composite gear, a preparation method and application thereof, which is prepared by mixing raw materials including the following components by mass: poly(lauryl lactam) 50-60 parts, polyformaldehyde 15-20 parts, a compatilizer 2-3 parts, a heat-conducting fiber 2-3 parts, a coupling agent 0.3-0.4 parts, a crystallization agent 0.1-0.2 parts, and an antioxidant 0.01-0.02 parts; the heat-conducting fiber is obtained by etching and glue-curing poly(ether ether ketone) fiber; and the crystallization agent is obtained by polycondensation reaction of p-dichlorobenzene, sodium sulfide and a biphenyl derivative. The composite gear prepared by using the crystallization agent and the heat-conducting fiber has a gear product crystallinity of 67.9%, a thermal conductivity of 3.34 W·(m·K) ‑1 , and excellent mechanical properties.

The invention belongs to the technical field of cultivation of new varieties of plants, and particularly relates to a breeding method and application of a bletilla striata triploid plant. The cultivation method of the bletilla striata triploid comprises the following steps: screening a bletilla striata diploid; artificially inducing and identifying the rhizoma bletillae tetraploid; cultivating the identified tetraploid until the tetraploid blooms; hybridizing the tetraploid and the diploid to obtain a rhizoma bletillae triploid fruit; wherein a mutagenic agent used for induction is a mixed aqueous solution of 10 ppm of p-dichlorobenzene and 5 ppm of alpha-bromonaphthalene. According to the invention, a new bletilla striata triploid strain is created for the first time, and a set of complete bletilla striata triploid advantage utilization and breeding method is established. The new bletilla striata triploid germplasm is obtained for the first time, and a scientific foundation is laid for bletilla striata triploid breeding.