A multidentate phosphite ligand is used in the catalytic synthesis of adiponitrile. The ligand is represented by the following general formula (I). The method of catalytic synthesis of adiponitrile comprises primary hydrocyanation, isomerization, and secondary hydrocyanation reactions, wherein the catalyst adopted each comprises a phosphite ligand-nickel complex composed of a nickel precursor and a multidentate phosphite ligand. The ligand molecule has a higher electron cloud density, and the phosphorus content capable of participating in coordination in the ligand molecule per unit mass is higher, so that the catalytic activity of the catalyst is improved, and the amount of the catalyst is reduced.
A multidentate phosphite ligand is used in the catalytic synthesis of adiponitrile. The ligand is represented by the following general formula (I). The method of catalytic synthesis of adiponitrile comprises primary hydrocyanation, isomerization, and secondary hydrocyanation reactions, wherein the catalyst adopted each comprises a phosphite ligand-nickel complex composed of a nickel precursor and a multidentate phosphite ligand. The ligand molecule has a higher electron cloud density, and the phosphorus content capable of participating in coordination in the ligand molecule per unit mass is higher, so that the catalytic activity of the catalyst is improved, and the amount of the catalyst is reduced.
C07C 253/10 - Preparation of carboxylic acid nitriles by addition of hydrogen cyanide or salts thereof to unsaturated compounds to compounds containing carbon-to-carbon double bonds
B01J 31/18 - Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes containing nitrogen, phosphorus, arsenic or antimony
C07F 9/06 - Phosphorus compounds without P—C bonds
C07F 9/6571 - Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom having phosphorus atoms, with or without nitrogen, oxygen, sulfur, selenium or tellurium atoms, as ring hetero atoms having phosphorus and oxygen atoms as the only ring hetero atoms
2.
CATALYST SYSTEM AND METHOD FOR CARBONYLATION REACTION
SHANDONG NHU FINE CHEMICAL SCIENCE AND TECHNOLOGY COMPANY LTD. (China)
Inventor
Wang, Chuang
Pan, Jiasheng
Li, Haoran
Hong, Xin
Zhang, Yuhong
Wu, Lei
Xu, Yong
Zhang, Shuoqing
Abstract
The present invention relates to a catalyst system for a carbonylation reaction and a method for a carbonylation reaction. The catalyst system comprises: (a) a group VIII metal or a compound of the group VIII metal; (b) a bidentate phosphine ligand; and (c) an acidic additive. The component (b) is represented by the following formula (I): R1>P-A-Ar-B-P
C07F 9/6568 - Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom having phosphorus atoms, with or without nitrogen, oxygen, sulfur, selenium or tellurium atoms, as ring hetero atoms having phosphorus atoms as the only ring hetero atoms
C07F 9/6571 - Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom having phosphorus atoms, with or without nitrogen, oxygen, sulfur, selenium or tellurium atoms, as ring hetero atoms having phosphorus and oxygen atoms as the only ring hetero atoms
C07F 9/6584 - Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom having phosphorus atoms, with or without nitrogen, oxygen, sulfur, selenium or tellurium atoms, as ring hetero atoms having phosphorus and nitrogen atoms with or without oxygen or sulfur atoms, as ring hetero atoms having one phosphorus atom as ring hetero atom
C07C 67/38 - Preparation of carboxylic acid esters by reaction with carbon monoxide or formates by addition to an unsaturated carbon-to-carbon bond
C07C 69/24 - Esters of acyclic saturated monocarboxylic acids having the carboxyl group bound to an acyclic carbon atom or to hydrogen having three or more carbon atoms in the acid moiety esterified with monohydroxylic compounds
C07C 69/612 - Esters of carboxylic acids having a carboxyl group bound to an acyclic carbon atom and having a six-membered aromatic ring in the acid moiety
C07C 69/75 - Esters of carboxylic acids having an esterified carboxyl group bound to a carbon atom of a ring other than a six-membered aromatic ring of acids with a six-membered ring
3.
METHOD FOR MANUFACTURING HIGH-REACTIVITY POLYPHENYLENE SULFIDE RESIN AND PRODUCT MANUFACTURED THEREBY
Disclosed in the present invention are a method for manufacturing high-activity polyphenylene sulfide (PPS) by regulating and controlling the water content in the polymerization process and a high-efficiency PPS resin manufactured thereby. The manufacturing method comprises: taking sodium hydrosulfide and p-dichlorobenzene as raw materials, taking N-methyl-2-pyrrolidone as a solvent, carrying out a polycondensation reaction until the conversion rate of p-dichlorobenzene reaches 97% or more, adding deionized water, reducing the temperature in a reaction kettle to 250-260°C, keeping the temperature for 1-3 h, and cooling for post-processing. The molar weight of the added deionized water is 1.0-2.5 mol based on 1.0 mol of sodium hydrosulfide. The method for manufacturing high-activity PPS disclosed in the present invention can be realized in the PPS polymerization process, that is, an end-capping reagent does not need to be additionally added, without affecting the molecular weight and thermal stability of the finally manufactured PPS; chain extension treatment does not need to be carried out after the PPS resin is manufactured, without additionally increasing the technological process and the production cost.
Disclosed are a poly(arylene sulfide) manufacturing process, a product thereof, and an application thereof. The manufacturing process uses a sulfur source and a dichloroaromatic compound as raw materials, utilizes an organic amide solvent, and performs a series of processes for preparation, including dehydration, pre-polymerization, polymerization, flash evaporation, post-treatment, etc. The invention creatively adds sodium chloride seed crystals into a reaction liquid during the pre-polymerization stage, and adds a filtration processing step for the reaction liquid after the pre-polymerization reaction ends. The use of the manufacturing process allows for greatly reducing the salt content of a prepared poly(arylene sulfide) resin crude product, greatly reducing the amount of high-salt wastewater generated, reducing water consumption and energy consumption, and helping to efficiently prepare a high-molecular-weight poly(arylene sulfide) resin; more importantly, the process is not only suitable as an intermittent process, but is likewise suited for continuous production, and is expected to greatly increase the production efficiency of the production system, reduce production costs and be more environmentally-friendly and green.
A method and apparatus for preparing methyl methacrylate (MMA) are provided. The method includes an aldol condensation reaction, a first distillation, a second distillation, a third distillation, a phase splitting, and a fourth distillation. Through the control of the process, the aldol condensation reaction can be performed when methyl propionate is used as the ninth material stream and formalin solution is used as the fifteenth stream material, MMA is obtained as the final product from the third material stream, and the waste with low content of residual formaldehyde is recovered from the eighth material stream.
11011011010 alkanoyl, aryl, heteroaryl, cyano, or nitro, and n is an integer from 1 to 8; and mixing the first preparation with the second preparation for a reaction, removing HCl generated by the reaction, filtering, and carrying out post-processing on a filtrate to obtain the phosphorus-containing ligand.
C07F 9/6506 - Five-membered rings having the nitrogen atoms in positions 1 and 3
C07F 9/6584 - Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom having phosphorus atoms, with or without nitrogen, oxygen, sulfur, selenium or tellurium atoms, as ring hetero atoms having phosphorus and nitrogen atoms with or without oxygen or sulfur atoms, as ring hetero atoms having one phosphorus atom as ring hetero atom
B01J 31/02 - Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
B01J 31/06 - Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides containing polymers
The present application relates to a preparation method and apparatus for methyl methacrylate. The preparation method comprises an aldol condensation reaction, first distillation, second distillation, third distillation, phase splitting, and fourth distillation, so that by means of the control of a process flow, it is only needed to use methyl propionate as a ninth material stream and use a formalin solution as a fifteenth material stream so as to perform the aldol condensation reaction, and a final product, i.e., methyl methacrylate, is obtained from a third material stream, and waste materials comprising low formaldehyde residues is recovered from an eighth material stream.
C07C 67/343 - Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group by isomerisationPreparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group by change of size of the carbon skeleton by increase in the number of carbon atoms
The present invention relates to an application of a polydentate phosphite ligand in the catalytic synthesis of adiponitrile. The ligand is represented by general formula (I). A method for catalytically synthesizing adiponitrile comprises a primary hydrocyanation reaction, an isomerization reaction and a secondary hydrocyanation reaction, wherein the catalysts used respectively comprise a phosphite ligand-nickel complex comprised of a nickel precursor and a polydentate phosphite ligand. The ligand molecule has a higher electron cloud density, and the content of phosphorus capable of participating in coordination in unit mass of the ligand molecule is higher, so that the catalytic activity of the catalyst is improved, and the amount of the catalyst is reduced. Furthermore, by designing and optimizing the ligand skeleton structure, the three-dimensional steric configuration of the phosphite ligand-nickel complex can be adjusted, and by combining with flexible regulation and control of the electronic effect and the steric hindrance effect of a substituent group on the ligand molecular structure, the chemical environment and the three-dimensional steric effect around a metal center can be changed, and the selectivity for the linear product adiponitrile is improved.
C07C 255/04 - Carboxylic acid nitriles having cyano groups bound to acyclic carbon atoms of an acyclic and saturated carbon skeleton containing two cyano groups bound to the carbon skeleton
C07C 253/10 - Preparation of carboxylic acid nitriles by addition of hydrogen cyanide or salts thereof to unsaturated compounds to compounds containing carbon-to-carbon double bonds
C07F 9/6571 - Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom having phosphorus atoms, with or without nitrogen, oxygen, sulfur, selenium or tellurium atoms, as ring hetero atoms having phosphorus and oxygen atoms as the only ring hetero atoms
9.
Porous Polymer and Method for Preparing the Same, Catalyst, and Method for Preparing Adiponitrile
A porous polymer has a pore volume of 0.3 to 2.5 cm3/g and comprises a pore having a first pore diameter and a pore having a second pore diameter. A ratio of pore volume of the pore having a first pore diameter to pore volume of the pore having a second pore diameter is 1 to 10:1. The porous polymer is obtained by self-polymerization or copolymerization of at least one of the phosphorus ligands, and phosphorous content of the porous polymer is 1 to 5 mmol/g. The porous polymer-nickel catalyst made of the porous polymer has a significant increase in water resistance, which may reduce the consumption of phosphorus ligands, eliminating the steps of removing water from raw materials and reaction system water control, which greatly saves process equipment investment. When used in the preparation of adiponitrile from butadiene, it has high catalytic activity, high reaction selectivity, and high linearity.
B01J 31/06 - Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides containing polymers
C08F 30/02 - Homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and containing phosphorus, selenium, tellurium or a metal containing phosphorus
C08J 9/14 - Working-up of macromolecular substances to porous or cellular articles or materialsAfter-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent organic
B01J 31/28 - Catalysts comprising hydrides, coordination complexes or organic compounds containing in addition, inorganic metal compounds not provided for in groups of the platinum group metals, iron group metals or copper
B01J 35/10 - Solids characterised by their surface properties or porosity
B01J 35/00 - Catalysts, in general, characterised by their form or physical properties
C07C 253/10 - Preparation of carboxylic acid nitriles by addition of hydrogen cyanide or salts thereof to unsaturated compounds to compounds containing carbon-to-carbon double bonds
Provided are a method and device for preparing adiponitrile. The method of the present disclosure comprises the steps of a first hydrocyanation reaction, an isomerization reaction and a second hydrocyanation reaction, wherein online Raman spectroscopy is used for detecting the content of a specific component in the system; and the reaction conditions are regulated based on the detection results, so as to achieve precise control of the materials in each step of the reaction system. The method of the present disclosure can reduce an amount of butadiene, thereby reducing the subsequent energy consumption needed for recycling butadiene and equipment investment after reaction; by monitoring the content of hydrocyanic acid in real time, the residue of hydrocyanic acid is reduced to a lower level, and the operation safety and the stability of a catalyst during reaction are improved; and the loss of the catalyst is reduced.
C07C 253/10 - Preparation of carboxylic acid nitriles by addition of hydrogen cyanide or salts thereof to unsaturated compounds to compounds containing carbon-to-carbon double bonds
11.
POROUS POLYMER, PREPARATION METHOD THEREFOR, CATALYST AND PREPARATION METHOD FOR ADIPONITRILE
A porous polymer having a pore volume of 0.3-2.5 cm3/g, the porous polymer comprising pores having a first pore diameter and pores having a second pore diameter, wherein the pore volume ratio of the pores having the first pore diameter to the pores having the second pore diameter is 1-10:1. The porous polymer is obtained by means of self-polymerization or copolymerization of at least one phosphorus ligand, and the phosphorus content of the porous polymer is 1-5 mmol/g. A porous polymer-nickel catalyst prepared from the porous polymer has significantly improved water resistance, can reduce the consumption of phosphorus ligands, omits the steps of water removal of raw materials and water control of a reaction system, and greatly saves on process equipment investment. In addition, when used for preparing adiponitrile by using butadiene, the catalyst has a high catalytic activity, a high reaction selectivity and high linearity, and is easy to recycle and reuse.
C08F 230/02 - Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and containing phosphorus, selenium, tellurium or a metal containing phosphorus
C08J 9/00 - Working-up of macromolecular substances to porous or cellular articles or materialsAfter-treatment thereof
B01J 31/18 - Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes containing nitrogen, phosphorus, arsenic or antimony
C07C 253/10 - Preparation of carboxylic acid nitriles by addition of hydrogen cyanide or salts thereof to unsaturated compounds to compounds containing carbon-to-carbon double bonds
C07C 255/04 - Carboxylic acid nitriles having cyano groups bound to acyclic carbon atoms of an acyclic and saturated carbon skeleton containing two cyano groups bound to the carbon skeleton
B01J 35/10 - Solids characterised by their surface properties or porosity
C08L 43/02 - Homopolymers or copolymers of monomers containing phosphorus
12.
HIGH-THERMAL-CONDUCTIVITY REINFORCED POLYPHENYLENE SULFIDE COMPOSITE MATERIAL AND PREPARATION METHOD THEREFOR
Disclosed are a high-thermal-conductivity reinforced polyphenylene sulfide composite material and a preparation method therefor, the high-thermal-conductivity reinforced polyphenylene sulfidecomposite material comprising the following raw materials by weight percentage: 30-50% of a polyphenylene sulfide base material; 5-30% of a surface carbonized reinforcing body; and 20-60% of a heat-conducting filler, the surface carbonized reinforcing body being a reinforcing body the outer surface of which is coated with a carbon layer. The preparation method comprises: blending a monomer raw material, a reinforcing body and an optionally added two-dimensional sheet-like heat-conducting filler, and passing through in-situ polymerization and carbonization to obtain a surface carbonized reinforcing body; and by using a polyphenylene sulfide base material, the heat-conducting filler and the prepared surface carbonized reinforcement as raw materials, passing through extrusion granulation to prepare and obtain a high-thermal-conductivity reinforced polyphenylene sulfide composite material. In the high-thermal-conductivity reinforced polyphenylene sulfide composite material disclosed, excellent processability and mechanical properties of the polyphenylene sulfide composite material are ensured while significantly improving the thermal conductivity of the polyphenylene sulfide composite material.
The present disclosure discloses a semi-aromatic polyamide and a preparation method therefor. The semi-aromatic polyamide is obtained by polymerization reaction using a diamine, a dibasic acid and a monoacid as main raw materials while adding a special end-capping agent. The semi-aromatic polyamide prepared according to the present disclosure has good thermal stability, a yellowness index of less than 20, a glass transition temperature of 90° C. or above, and a melting point of 300° C. or above, and can be applied to spare parts for fuel pipelines in automobiles, and electronic and electrical industries such as LED panels.
C08G 69/48 - Polymers modified by chemical after-treatment
C08G 69/26 - Polyamides derived from amino carboxylic acids or from polyamines and polycarboxylic acids derived from polyamines and polycarboxylic acids
Provided are a method and device for preparing adiponitrile. The preparation method of the present invention comprises the steps of a first hydrocyanation reaction, an isomerization reaction and a second hydrocyanation reaction, wherein on-line Raman spectroscopy is used for detecting the content of a specific ingredient in the system; and on the basis of the detection results, the reaction conditions are regulated, so as to achieve precise control over a substance in each step in the reaction system. The method of the present invention can reduce the amount of butadiene, thereby reducing the subsequent energy consumption needed for recycling butadiene and equipment investment after reaction; by means of the real time monitoring of the content of hydrocyanic acid, the residue of hydrocyanic acid is reduced to a lower level, and the operation safety and the stability of a catalyst during reaction are improved; and the loss of the catalyst is reduced.
C07C 253/10 - Preparation of carboxylic acid nitriles by addition of hydrogen cyanide or salts thereof to unsaturated compounds to compounds containing carbon-to-carbon double bonds
C07C 255/04 - Carboxylic acid nitriles having cyano groups bound to acyclic carbon atoms of an acyclic and saturated carbon skeleton containing two cyano groups bound to the carbon skeleton
15.
SEMI-AROMATIC POLYAMIDE THERMOPLASTIC ELASTOMER AND CONTINUOUS PRODUCTION METHOD THEREFOR
A continuous production method for a semi-aromatic polyamide thermoplastic elastomer, comprising: mixing an aromatic dibasic acid, a diamine and a molecular weight regulator with water and a catalyst to form a slurry, and then dissolving at an elevated temperature to form a salt solution, the molecular weight regulator being selected from dibasic acid monoesters; dehydrating the salt solution prepared in the previous step and then carrying out a pre-polymerization reaction, performing flash evaporation on the obtained pre-polymerization reaction liquid; and then completing a post-condensation reaction between the product resulting from flash evaporation and a polymer polyol under the action of a transesterification catalyst. The described production process uses non-toxic and inexpensive aromatic dibasic acid as a raw material to prepare a semi-aromatic polyamide thermoplastic elastomer, has high reaction activity and a short reaction time, uses a molten system reaction, does not use an organic solvent, and is environmentally friendly. The prepared semi-aromatic polyamide thermoplastic elastomer is mainly terminated by ester groups, has excellent thermodynamic and mechanical properties, and also has excellent hydrolysis resistance.
Disclosed is a continuous washing process for a polyphenylene sulfide (PPS) slurry, which mainly comprises the following steps: pressurizing and heating a PPS slurry, and then feeding same to the top of a washing tower, while feeding a high-temperature washing liquid to the bottom of the washing tower; using the high-temperature washing liquid in the tower to perform countercurrent washing on the PPS slurry to obtain a washed PPS resin at the bottom of the tower. The process significantly improves the washing efficiency, and the salt content of the product can be reduced to less than 0.2%.
The present disclosure discloses a preparation method for 4-phenylthio-benzenethiol. The preparation method comprises the following steps: subjecting phenyl sulfide as a raw material to a halogenation reaction to obtain 4-halophenyl sulfide; subjecting the 4-halophenyl sulfide to a sulfhydrylation reaction to obtain a 4-phenylthio-phenylthiolate; and subjecting the 4-phenylthio-phenylthiolate to acidification. The preparation method of the present disclosure avoids the use of materials such as thiophenol which pollutes the environment, and realizes efficient recycling of the reaction materials, solvents, water and the like. The preparation method of the present disclosure is a green process for the synthesis of 4-phenylthio-phenylthiol without organic waste, waste acid and waste water discharge.
C07C 319/20 - Preparation of thiols, sulfides, hydropolysulfides or polysulfides of sulfides by reactions not involving the formation of sulfide groups
C01D 5/02 - Preparation of sulfates from alkali metal salts and sulfuric acid or bisulfatesPreparation of bisulfates
18.
Preparation method of polyphenylene sulfide resin, and polyphenylene sulfide resin prepared thereby
A preparation method of a polyphenylene sulfide resin, and a polyphenylene sulfide resin prepared by the method using a sulfur-containing compound, an alkaline substance and p-dichlorobenzene as raw materials, a fatty acid as a polycondensation aid to carry out a polycondensation reaction. After purification treatment, a primary polyphenylene sulfide is obtained, which then reacts with a terminal-group adjusting agent at a high temperature to generate the polyphenylene sulfide resin resulting in high yield and low cost. The prepared polyphenylene sulfide resin has high reactivity, high melting crystallization temperature and excellent thermal stability. The resulting polyphenylene sulfide resin can be directly used for extrusion and injection molding.
A polyarylene sulfide granule, a preparation method therefor and a molded product thereof, wherein the surface of the granule has a porous structure, functional additives are adsorbed on at least a part of the surface of the porous structure, and the granule comprises polyarylene sulfide particles and/or slices.
C08K 5/524 - Esters of phosphorous acids, e.g. of H3PO3
C08J 3/20 - Compounding polymers with additives, e.g. colouring
D06M 101/30 - Synthetic polymers consisting of macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
A spinning method and apparatus. The method and apparatus are suitable for the production of polyarylene sulfide fibers having relatively high glass transition temperature. By adding the fibers into an oil bath storage tank, uniform heating during fiber drawing can be maintained and the heating temperature can be precisely controlled; the damage to equipment and to the quality of the fibers in an oil bath tank due to high temperature transmission of a heating medium is avoided, and the problem of insufficient utilization of the heating medium caused by the reduction of starting and stopping efficiency and the drastic change in the flow of the heating medium when the equipment is started or stopped is avoided.
Disclosed are semi-aromatic polyamide and a preparation method therefor. The semi-aromatic polyamide is obtained by taking diamine, dibasic acid, and monoacid as main raw materials, and adding a specific end-capping agent for polymerization reaction. The semi-aromatic polyamide prepared in the present invention is good in thermal stability, and has a yellowness index of less than 20, a glass transition temperature of above 90°C, and a melting point of above 300°C, and can be applied to parts such as vehicle fuel pipelines, and electronic and electrical industries such as LED panels.
C08G 69/48 - Polymers modified by chemical after-treatment
C08G 69/26 - Polyamides derived from amino carboxylic acids or from polyamines and polycarboxylic acids derived from polyamines and polycarboxylic acids
The present invention relates to a high-molecular-weight polyphenylene sulfide resin and preparation method and use thereof. In the present invention, sulfur-containing compound and halogenated aromatic compound are used as raw materials, and basic compound and fatty acid as polycondensation agent; a polycondensation reaction is performed, and, after purification, a polyphenylene sulfide primary product is obtained; said polyphenylene sulfide primary product is then reacted with a chain extender at high temperature to produce a high-molecular-weight polyphenylene sulfide resin. The preparation method of the present invention has high yield and low cost, and has the features of selective and controllable preparation of polyphenylene sulfide resins having different melt viscosities and molecular weights; the obtained polyphenylene sulfide resins have excellent heat resistance. The linear high-molecular-weight polyphenylene sulfide resin having high thermal stability obtained by the present invention can be used for the production of plate, pipe, and rod material, and, like metal, can be cut, ground, polished, drilled, and otherwise mechanically processed, and can also be used for making fibers, membranes, and films, and is especially suitable for automotive component parts, electronic/electrical devices, chemical engineering, and mechanical industries.
The present disclosure provides a production method of a semi-aromatic polyamide, and a semi-aromatic polyamide. Said production method of a semi-aromatic polyamide includes: step 1 of subjecting an initial charge of a diamine and a binary acid in an amine/acid molar ratio of less than 1.0 to form a slurry together with water and a catalyst, and subjecting the slurry to heating and dissolution to form a saline solution; step 2 of dehydrating said saline solution after detecting the composition thereof, detecting the content of diamine in a steam condensate from a dehydration unit, adjusting the amine/acid molar ratio to be larger than 1.0 by a molten diamine and a monoacid as a molecular weight regulator, and performing pre-polymerization; and step 3 of subjecting a pre-polymerization solution to post-polycondensation after vacuum flashing. The semi-aromatic polyamide of the present disclosure has a low gel content, excellent performance and extensive scope of application.
C08G 69/26 - Polyamides derived from amino carboxylic acids or from polyamines and polycarboxylic acids derived from polyamines and polycarboxylic acids
Provided is a method for detecting sodium polysulfide, comprising the following steps: a) adding an ammonium salt agent to an analyte, such that sodium polysulfide in the analyte reacts with the ammonium salt, and determining, by means of a potentiometric titration method, the titration end point to obtain a sulfur deposit; and b) performing, according to a molar quantity of ammonium ions in the ammonium salt agent consumed in step a) and a mass of the sulfur deposit, calculation to obtain a sodium polysulfide content in the analyte.
G01N 31/16 - Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroupsApparatus specially adapted for such methods using titration
25.
PREPARATION METHOD FOR POLYPHENYLENE SULFIDE AND POLYPHENYLENE SULFIDE PREPARED BY MEANS OF SAME
A preparation method for polyphenylene sulfide, and polyphenylene sulfide prepared by means of the same. The method comprises: carrying out a polycondensation reaction by using an alkaline substance and p-dichlorobenzene as raw materials and by using fatty acid as a polycondensation additive, obtaining a primary product of polyphenylene sulfide after performing purification processing, then reacting the same with a terminal regulator at a high temperature to produce polyphenylene sulfide. The preparation method has a high yield and is low cost, and the prepared polyphenylene sulfide has high reactive activity, high melting crystallization temperature and excellent heat resistance. The polyphenylene sulfide may be directly used for extrusion and injection, and is particularly suitable for the fields of automobile parts, electronic/electrical equipment, the chemical industry, the machinery industry, and so on.
Disclosed in the present invention is a preparation method for 4-phenylthio-benzenethiol. The preparation method comprises the following steps: subjecting phenyl sulfide as a raw material to a halogenation reaction to obtain 4-halophenyl sulfide; subjecting the 4-halophenyl sulfide to a sulfhydrylation reaction to obtain a 4-phenylthio-phenylthiolate; and subjecting the 4-phenylthio-phenylthiolate to acidification. The preparation method of the present invention avoids the use of materials such as thiophenol which pollute the environment, and realizes efficient recycling of the reaction materials, solvents, water and the like. The preparation method of the present invention is a green process for the synthesis of 4-phenylthio-phenylthiol without organic waste, waste acid and waste water discharge.
C07C 319/20 - Preparation of thiols, sulfides, hydropolysulfides or polysulfides of sulfides by reactions not involving the formation of sulfide groups
C07C 323/09 - Thiols, sulfides, hydropolysulfides or polysulfides substituted by halogen, oxygen or nitrogen atoms, or by sulfur atoms not being part of thio groups containing thio groups and halogen atoms, or nitro or nitroso groups bound to the same carbon skeleton having sulfur atoms of thio groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton
27.
METHOD FOR PRODUCING SEMI-AROMATIC POLYAMIDE AND SEMI-AROMATIC POLYAMIDE
A method for producing a semi-aromatic polyamide and a semi-aromatic polyamide. The method for producing the semi-aromatic polyamide comprises: step 1, forming a slurry by mixing an initial charge of a diamine and a dibasic acid with an amine/acid molar ratio being less than 1.0 and water as well as a catalyst, heating the slurry and dissolving same into a salt solution; step 2, detecting the composition of the salt solution, then dehydrating the salt solution, detecting the content of the diamine in steam condensate discharged from the dehydrating device, and using a molten diamine and a molecular weight regulator monobasic acid to adjust the amine/acid molar ratio to more than 1.0, so as to perform prepolymerization; and step 3, reducing the pressure of a prepolymerization reaction liquid and performing flash evaporation to perform post-polycondensation. The semi-aromatic polyamide product prepared in the method has a low gel content and excellent properties, and is suitable for a wide range of applications.
C08G 69/26 - Polyamides derived from amino carboxylic acids or from polyamines and polycarboxylic acids derived from polyamines and polycarboxylic acids
A polyphenylene sulfide having a low chlorine content, a preparation method therefor, a resin composition, and a formed body; the polyphenylene sulfide having a low chlorine content is obtained by capping 4-thiophenyl-thiophenol. The preparation method of the polyphenylene sulfide uses a sulfocompound, an alkaline substance and p-dichlorobenzene as raw materials, a fatty acid as a polycondensation additive, and 4-thiophenyl-thiophenol (PTT) as a terminal group modifier for condensation polymerization. Product yield is high and cost is low; the obtained polyphenylene sulfide product has low chlorine content, and also has excellent flowability and heat resistance; thus, the product can satisfy the use requirements for low chlorine and high flowability in the electronic and electric trade.
4, and whiteness is over 90, it can satisfy requirements for fiber polyphenylene sulfide resin. C5-C6 fatty acid salt according to the method of the present invention has a higher solubility in NMP, which can better promote polymerization. It is to be fully diverted into the filtrate after filter prior to conversion into free fatty acid again through acidification with hydrochloric acid. C5-C6 fatty acid is available for azeotropy with water, which has a limited solubility in water. Therefore, it is applicable to recycle C5-C6 fatty acid from the filtrate through azeotropy with water, and thereby solve the problem with separation of additive and sodium chloride that are soluble in water.
C08G 75/16 - Polysulfides by polycondensation of organic compounds with inorganic polysulfides
C08G 75/00 - Macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing sulfur, with or without nitrogen, oxygen, or carbon
Disclosed is a method for synthesizing a fibre-grade polyphenylene sulphide resin, comprising synthesizing via a polycondensation reaction by using a sodium hydrosulphide solution and p-dichlorobenzene as raw materials, N-methyl-2-pyrrolidone as a solvent, and a C5-C6 fatty acid salt formed by dehydration of a C5-C6 fatty acid and sodium hydroxide as an auxiliary for the polycondensation reaction. The reaction liquid is subjected to acidification and washing to obtain a white polyphenylene sulphide resin, the melt flow rate of the product is less than 125 g/10 min, the weight-average molecular weight measured by GPC is greater than 4.2 × 104, and the whiteness is higher than 90, meeting the requirements of the fibre-grade polyphenylene sulphide resin. In the method of the present invention, the C5-C6 fatty acid salt used has good solubility in NMP and can better promote the polycondensation reaction, all of it enters a filtrate after reaction and filtration, and it is again converted into a free fatty acid through acidification with hydrochloric acid; and the C5-C6 fatty acid can co-boil with water, has low solubility in water, and can be recovered from the filtrate by the method of co-boiling with water, thereby avoiding the problem that both the auxiliary and sodium chloride are dissolved in water and cannot be separated and recovered.
patents
