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79 results about "Cyclic siloxane" patented technology

Nano-composite silicone rubber insulator with hydrophobic mobility and manufacturing method of nano-composite silicone rubber insulator

The invention provides a nano-composite silicone rubber insulator with hydrophobic migration and a manufacturing method thereof, the nano-composite silicone rubber insulator comprises a core rod and an umbrella skirt sheath, and the umbrella skirt sheath comprises the following raw materials: a silicone rubber matrix, phenyl silicone rubber, linear polydimethylsiloxane, microencapsulated cyclic siloxane and a functional filler. Through a dual-mechanism hydrophobic migration system, a multi-scale filler framework and filler frameworks of different dimensions, a mechanically enhanced continuous path is provided, smoothness of a low-molecular-weight siloxane migration channel under a low-temperature condition is ensured, and through cooperation of anisotropy of the boron nitride nanosheets and microencapsulated cyclic siloxane, the low-molecular-weight siloxane migration channel is improved. The volatilization rate of low-molecular-weight siloxane under a high-temperature condition is reduced, and the hydrophobic migration stability of the insulator under severe environments such as low temperature and high temperature is greatly improved.
Owner:LILING PUKOU ELECTRIC PORCELAIN MFG CO LTD

Base material of self-lubricating sliding bearing as well as preparation method and application of base material

The invention relates to a base material of a self-lubricating sliding bearing as well as a preparation method and application of the base material. The base material comprises a component A, a component B and a component C, and the mass ratio of the component A to the component B to the component C is (0.4-0.8): (0.1-0.3): (0.1-0.3); wherein the component A is prepared from the following raw materials: vinyl cyclic siloxane, 1-thioglycerol and methacryloyl isocyanate; the component B is prepared from the following raw materials: a hexamethylene diisocyanate tripolymer and 2-hydroxy propyl methacrylate; and the component C is prepared from the following raw materials: a diphenylmethane diisocyanate tripolymer and 2-hydroxy propyl methacrylate. The compression strength and the compression modulus of the base material are both higher than those of commercially available resin, the bearing performance of the self-lubricating sliding bearing is greatly improved, meanwhile, the wear rate of the bearing is reduced through the high-crosslinking-degree resin, the gasket is more wear-resistant, and the service life of the bearing is prolonged.
Owner:TSINGHUA UNIVERSITY

Purified polyether siloxanes i

PCT designated stageWO2026021896A1Polymer scienceOrganic chemistry
The present invention relates to a polyether siloxane comprising at least one siloxane block and at least one polyether block, characterized in that the polyether siloxane comprises not more than 0.015 wt.-% of at least one cyclic siloxane D4 to D6.
Owner:EVONIK OPERATIONS GMBH

Anti-blocking liquid packaging film and preparation process

The present application relates to the technical field of anti-adhesion packaging material research and development, and discloses an anti-adhesion liquid packaging film and a preparation process, which comprises the following steps: synthesizing octahexyl double-layer cyclic siloxane monomer, preparing an organic-inorganic hybrid type connecting agent through addition reaction of Si-H bonds of the octahexyl double-layer cyclic siloxane monomer and olefinic functional groups of an allyl silane coupling agent, modifying and treating hydroxylated silicon dioxide nanoparticles through the organic-inorganic hybrid type connecting agent, and then dispersing the hydroxylated silicon dioxide nanoparticles in a PE-SILICON-PE block copolymer matrix to prepare an anti-adhesion composite material; a film structure of a nine-layer co-extrusion film is arranged, the anti-adhesion composite material is introduced into the first layer and the ninth layer of the nine-layer co-extrusion film, and a nine-layer co-extrusion blown film process is used to prepare a packaging film with excellent anti-adhesion performance, which can be applied in the field of non-Newtonian liquid product packaging.
Owner:SUZHOU ZIJIN PLASTIC

Non-aqueous electrolytes and lithium secondary batteries containing them

The present invention relates to a non-aqueous electrolyte comprising a lithium salt, an organic solvent, and an additive, wherein the additive comprises a cyclic siloxane compound represented by a specific chemical formula.
Owner:LG ENERGY SOLUTION LTD

Silicone hydrogel polymer material for contact lenses and preparation method thereof

The invention discloses a silicone hydrogel polymer material for contact lenses and a preparation method thereof, and relates to the field of high polymer materials. Siloxane monomers, hydrophilic monomers and a dynamic cross-linking agent are mixed to obtain a monomer mixed solution; mixing functional nanoparticles, the monomer mixed solution and an initiator to obtain a pre-polymerized solution; according to the silicon hydrogel polymer material for the contact lens, the cyclic siloxane monomer and the linear siloxane are copolymerized to form a hydrophobic micro-area with a controllable size, the oxygen permeability is optimized, a borate bond is introduced as a dynamic crosslinking point, a network is reconstructed when ocular surface inflammation occurs, and the contact lens has the advantages that the contact lens is not prone to inflammation; functional nano-particle loaded anti-inflammatory and antibacterial components are released, and the high-oxygen-permeability, intelligent anti-inflammatory and antibacterial, ultra-durable and comfortable silicon hydrogel polymer material for the contact lenses is obtained.
Owner:IRIS (XIAMEN) TECH CO LTD

Preparation method of sodium difluorophosphate

The invention relates to a preparation method of sodium difluorophosphate, which comprises the following steps: S1, reacting sodium hexafluorophosphate with cyclic siloxane in an aprotic organic solvent at 50-80 DEG C, and filtering after the reaction to obtain a sodium difluorophosphate crude product and mother liquor; s2, the sodium difluorophosphate crude product is subjected to ultrasonic washing with a washing solvent, a sodium difluorophosphate wet solid is obtained, and the washing solvent is a mixed solvent of tetrahydrofuran and any one of dimethyl carbonate, ethyl acetate and ethylene glycol dimethyl ether; and S3, gradually heating the sodium difluorophosphate wet solid, carrying out vacuum drying, and introducing inert gas at intervals in the drying process for replacement. The method is wide in reaction raw material source, low in price, mild in reaction condition, convenient to operate and easy for industrial production; and the prepared sodium difluorophosphate has high purity and high yield, and can meet the relevant requirements of battery application.
Owner:JIANGSU GUOTAI SUPER POWER NEW MATERIALS

Polymer waterproof coiled material and preparation method thereof

The invention relates to the technical field of waterproof coiled materials, in particular to a macromolecular waterproof coiled material and a preparation method thereof. The waterproof roll structurally comprises the release film, the waterproof layer, the polymer layer, the aggregate layer, the polymer layer, the waterproof layer and the release film in sequence from outside to inside, and the problems that a waterproof roll is poor in waterproof effect and poor in aging resistance are solved. The polymer waterproof roll mainly comprises a release film, a waterproof layer, a polymer layer and an aggregate layer. The reaction temperature and time are adjusted by adjusting the types of cyclic siloxane in the aggregate layer and the waterproof layer; the synthetic plasticizer is added into the polymer layer; synthesizing polyarylsulfone, and adding the polyarylsulfone into the high-molecular waterproof coiled material, the component proportion of the raw materials of the polymer layer is changed; finally, bentonite is modified, and the modified bentonite is used in the waterproof layer. The prepared high-molecular waterproof coiled material is good in waterproof effect and high in peel strength after thermal aging.
Owner:韦贝贝

Fluorine-free ester-based electrolyte, preparation method and high-voltage lithium ion battery

The application provides a fluorine-free ester-based electrolyte, a preparation method and a high-voltage lithium ion battery. The fluorine-free ester-based electrolyte comprises a lithium salt, a fluorine-free solvent and a fluorine-free additive; the fluorine-free solvent is a methylated linear carbonate and / or a methylated linear carboxylate, and the fluorine-free additive is a cyclic boroxine or a cyclic siloxane with 3-5 carbon-carbon double bonds; the methylated linear carbonate has a general structural formula as shown in formula (1); wherein R1 and R2 are independently alkyl groups with 1-4 carbon atoms, and the carbon atom number of at least one of R1 and R2 is greater than or equal to 3; the methylated linear carboxylate has a general structural formula as shown in formula (2); wherein R3 is a hydrogen atom or an alkyl group with 1-4 carbon atoms, R4 is an alkyl group with 2-4 carbon atoms, and the carbon atom number of at least one of R3 and R4 is greater than or equal to 3. The fluorine-free ester-based electrolyte can significantly prolong the cycle life of the lithium ion battery.
Owner:TSINGHUA SHENZHEN INTERNATIONAL GRADUATE SCHOOL

Sodium-ion battery electrolyte and sodium-ion battery

The invention provides a sodium-ion battery electrolyte and a sodium-ion battery, and relates to the technical field of electrolytes. According to the sodium-ion battery electrolyte disclosed by the invention, the cyclic siloxane compound and the bicyclic sulfate compound of which at least one silicon atom is simultaneously connected with alkenyl and phenyl are added as electrolyte additives, so that the thermal stability of a sodium-ion battery is improved, and meanwhile, the interface impedance of the battery can be prevented from being increased; therefore, the obtained sodium ion battery has high-temperature stability and low interface impedance.
Owner:JIANGSU YIN GONG TECHNOLOGY CO LTD

Thermally conductive silicone compositions and methods for making same

PendingCN120641467APolymer sciencePtru catalyst
Provided is a thermally conductive silicone composition for forming a cured product, which exhibits high heat dissipation performance, does not produce voids, and has excellent processability. The thermally conductive silicone composition includes: an organopolysiloxane (A) containing an alkenyl group; a linear organopolysiloxane (B) having two or more hydrosilyl groups in one molecule; a hydrogenated cyclic siloxane (C) having only repeating units of-SiRHO-and having a degree of polymerization of 4 to 8; an addition reaction catalyst (D); and a thermally conductive filler (E). In the composition, the content of the component (C) is 0.5 to 1.8 parts by mass or less and the content of the component (E) is 500 to 3,000 parts by mass or less with respect to 100 parts by mass of the total amount of the components (A) and (B).
Owner:WACKER CHEMIE AG

Energy-saving purification and precision filtration processing method for recycling silica gel

The application discloses an energy-saving purification and precision filtration processing method of recycled silica gel materials, and relates to the technical field of high polymer material recycling. After waste silica gel is melted and plasticized, the waste silica gel is sequentially subjected to two purification procedures of ultrasonic field auxiliary dynamic self-cleaning step-by-step filtration and low-temperature vacuum membrane distillation ring removal, and waste heat generated in the two procedures is reversely transported to a front-end preheating plasticizing procedure through a closed heat-conducting fluid loop. A differential pressure feedforward composite control algorithm is used in the filtration procedure, a differential pressure change rate is used as a feedforward trigger signal to adaptively adjust the power and frequency of an ultrasonic transducer array, white carbon black secondary agglomerates are dispersed in situ, and the filter screen is flushed, so that continuous filtration is realized without shutdown. In the ring removal procedure, D3 to D6 cyclic siloxanes are targetedly removed in a vacuum environment of not more than 1 kPa at 130 DEG C to 160 DEG C by using oil-repellent modified PTFE hollow fiber membranes, the residual amount of D4 / D5 can be reduced to below 0.1 wt%, and secondary thermal degradation is inhibited.
Owner:JIAFUNUO TECHNOLOGY (SUZHOU) CO LTD

Medical silicone gel for scar repair and method of preparation and use thereof

The application discloses a medical silicone gel for scar repair and a preparation method and application thereof, and belongs to the technical field of biomedical materials and tissue engineering. The medical silicone gel comprises the following components in percentage by mass: cyclic siloxane 1-10%, silicone 30-50%, polysiloxane polymer 10-30%, gel matrix 1-10%, and the balance is water. The silicone gel provided by the application is stable in property, has no cytotoxicity, has no skin irritation, is easy to spread, has good film forming property, has strong adhesion to skin tissue, has a tension reducing and pressure adding effect on scars, and has a better scar repair effect than that of a commercial product.
Owner:ZHONGSHAN HOSPITAL FUDAN UNIV +1

Preparation method of alkyl-functionalized polysiloxanes

This disclosure relates to a method for preparing alkyl-functionalized polysiloxanes, comprising the steps of: I) reacting a silane oligomer with a hydroxyl-terminated polysiloxane in the presence of catalyst 1, and II) reacting the reactant obtained in step (I) with a capping agent in the presence of catalyst 2, thereby obtaining the polysiloxane. This method allows for flexible adjustment of the degree of polymerization and viscosity of the desired polysiloxane by adjusting the feedstock, making it suitable for different applications; it can introduce multiple alkyl functional groups and further functional groups to obtain dual-modified polysiloxanes; using linear hydroxyl-terminated polysiloxanes as starting materials significantly reduces the proportion of undesirable cyclic siloxanes in the equilibrium product; and the reaction is mild, simple to operate, and environmentally friendly.
Owner:WACKER CHEMIE AG

Organic heat-resistant additive, high-temperature-resistant transparent silicone rubber and preparation method of organic heat-resistant additive

PendingCN121628121AMetal chloridePtru catalyst
The invention discloses an organic heat-resistant additive, high-temperature-resistant transparent silicon rubber and a preparation method of the organic heat-resistant additive, and belongs to the field of organic silicon materials. The preparation method of the organic heat-resistant additive comprises the following steps: uniformly mixing a cyclic siloxane solution with lithium dimethyl vinyl silanolate, stirring at 25 DEG C for 12 hours, dropwise adding a metal chloride solution into a reaction system, stirring for reaction, and purifying to obtain metal hybrid vinyl-terminated polysiloxane, and dissolving the polysiloxane and thioether-containing silane in toluene, adding a platinum catalyst, carrying out a stirring reaction, and carrying out vacuum concentration to obtain the thioether-containing polysiloxane. The synthesized organic heat-resistant additive is added into liquid silicone rubber to prepare the high-temperature-resistant transparent silicone rubber. The organic heat-resistant additive disclosed by the invention has excellent dispersity and compatibility in the silicone rubber, can ensure the transparency, mechanical properties and processability of the material while remarkably improving the thermo-oxidative aging resistance of the silicone rubber, and meets the use requirements of special application scenes under some harsh conditions.
Owner:CHINA BLUESTAR CHENGRAND CO LTD +1

Alcohol-modified silicone emulsion and its preparation method and application

The present invention discloses a kind of alcohol-modified organosilicon emulsion and its preparation method and application. The alcohol-modified organosilicon emulsion is formed by the mixed reaction of the following components by mass fraction: 20%~30% of cyclic siloxane, 1%~3% of epoxyalkoxysilane, 0.5%~5% of nonionic surfactant, 5%~10% of anionic surfactant, 1%~2% of strong acid, 0.1%~0.5% of chain capping agent, 1%~5% of hydroxyl-terminated polydiorganosiloxane, and the balance is water. The alcohol-modified organosilicon emulsion of the present invention can be mixed with amino-modified silicone emulsion or epoxy-modified organosilicon emulsion in proportion, and is moderately cross-linked. It can form a film to better protect the fiber, and can avoid the sticky roller phenomenon caused by excessive cross-linking of traditional amino-epoxy-modified organosilicon emulsion during heating, and fiber quality and processability are greatly improved and improved.
Owner:JIANGSU ZHONGFU SHENYING CARBON FIBER ENG CENT CO LTD

Reactive phosphate functional emulsifier and preparation method thereof

The application discloses a reactive phosphate functional emulsifier and a preparation method thereof, relates to the technical field of emulsifiers, and comprises the following steps: mixing vinyl salicylaldehyde, ethyl acetate and triethylamine, stirring under an inert atmosphere, adding phenyl phosphorodichloridate in an ice bath, centrifuging, washing and drying after warming reaction to obtain a preform; ultrasonically mixing the preform with anhydrous ethanol, adding hyperbranched polyether amine, continuously ultrasonically mixing, then adding 2-amino-4-fluorothiophenol for constant-temperature reaction, washing and drying after removing the solvent to obtain a mixture; stirring the mixture with anhydrous ethanol and an initiator, high-speed dispersing cyclic siloxane, adding glycidyl methacrylate for heating reaction, washing and drying after gradient cooling and solidification to obtain the emulsifier; by introducing cyclic siloxane and hyperbranched polyether amine, a hydrophobic film and a hydrogen bond network hierarchical protection system are constructed, the hydrolysis resistance and the flame resistance of the emulsifier are improved, and the stability of water-based paint is improved.
Owner:ZHAOQING SHUOBO TECHNOLOGY CO LTD

Resin composition and gear

A resin composition containing a polyaryl ketone, the resin composition containing a polysiloxane having a structure represented by formula (1), a peak corresponding to a cyclic siloxane being detected in pyrolysis GC / MS of the resin composition, and the content ratio of the polysiloxane in the resin composition being 0.25-1.25 mass%. (In formula (1), R1 and R2 each independently represent an alkyl group having 1-3 carbon atoms)
Owner:POLYPLASTICS-EVONIK CORP

Removal of silicones and other impurities in pyrolysis oil using silica gel matrices

A process to reduce siloxanes in a waste plastic pyrolysis oil composition is disclosed. The process can include contacting the waste plastic pyrolysis oil composition with a modified silica gel composition under conditions sufficient to produce a purified waste plastic pyrolysis oil composition. The purified waste plastic pyrolysis oil composition can have at least 50% by weight less siloxanes, preferably at least 60% by weight less siloxanes, as compared to the untreated waste plastic pyrolysis oil composition. The siloxanes can include acyclic siloxanes, cyclic siloxanes, or a combination thereof. The modified silica gel composition can include cobalt or iron compositions.
Owner:SABIC GLOBAL TECHNOLOGIES BV

Wafer surface modification composition and application thereof in preventing high aspect ratio pattern from collapsing

The invention relates to a wafer surface modification composition and application thereof in preventing collapse of a high aspect ratio pattern. The composition comprises: (a) an organic solvent; (b) 0.1 to 1 wt% of a fluoropolymer; (c) 1 to 10 wt% of a silane coupling agent; (d) 1 to 10 wt% of a long-chain cyclic siloxane solvent; and (e) 0.01 to 0.1 wt% of a catalyst. During application, the super-hydrophobic film layer is constructed on the surface of the wafer, so that the Si / SiO2 / Si3N4 contact angle is increased from 44 degrees / 28 degrees / 18 degrees to 94 degrees / 102 degrees / 105 degrees or above, and the pattern of the wafer with the high aspect ratio structure does not collapse after being etched, cleaned and dried.
Owner:HUBEI SINOPHORUS ELECTRONIC MATERIALS CO LTD

Silica gel chemical recovery process

The invention discloses a silica gel chemical recovery process, and belongs to the technical field of silicone rubber. The process comprises the following steps: disassembling, sorting, crushing, cleaning and drying the waste silica gel parts; mixing the pretreated silica gel particles with a specific cracking catalyst, carrying out catalytic cracking in an inert atmosphere, and collecting condensed crude silicone oil; carrying out reduced pressure distillation, molecular distillation and adsorption refining on the crude silicone oil to obtain high-purity regenerated silicone oil which takes cyclic siloxane such as octamethylcyclotetrasiloxane as a main component; and carrying out balanced polymerization and end group regulation on the regenerated silicone oil, a cyclic monomer and an end group regulator to obtain the regenerated silicone rubber-based rubber. The regenerated liquid silicone rubber product is obtained by compounding regenerated silicone rubber base rubber, a cross-linking agent, a filler and the like and vulcanizing. Compared with the prior art, the recovery process has the advantages of less carbon emission and higher material purity, and meets the requirements of high-end products.
Owner:ZHAOQING TEPUAI POLYMER MATERIALS CO LTD

Black Photosensitive Resin Composition, Black Matrix and Display Device

InactiveKR102992209B1Polymer scienceImage resolution
The present invention relates to a black photosensitive resin composition comprising a black coloring agent, an alkali-soluble resin, a photopolymerizable compound, a photopolymerization initiator, one or more of a cyclic siloxane compound containing an epoxy group and a silsesquioxane compound, a thiol compound, and a solvent, a black matrix formed using the same, and an image display device comprising the black matrix. The black photosensitive resin composition according to the present invention exhibits a pure taper shape even when low-temperature curing and a TMAH-based developer are applied, and can form a pattern with excellent reflectance retention rate, resolution, solvent resistance, and pencil hardness.
Owner:DONGWOO FINE CHEM CO LTD

Method for removing trace boron and phosphorus impurities in trichlorosilane

The invention discloses a method for removing trace boron and phosphorus impurities in trichlorosilane, which belongs to the technical field of chlorosilane purification, and comprises the following steps: adding a complexing agent into crude liquid trichlorosilane, carrying out complexation reaction, and rectifying the mixture obtained by the reaction to obtain the purified trichlorosilane, the cyclic siloxane and the chain siloxane have the advantages that the stability is high, new impurities are not easy to introduce, the compatibility with chlorosilane is good, and the like, so that ppb-level boron and phosphorus impurities can be efficiently removed; the trichlorosilane purified by the method is suitable for production of electronic-grade polycrystalline silicon.
Owner:EAST CHINA UNIV OF SCI & TECH

Organosilicone acrylic acid grafted copolymer resin emulsion and preparation method and application thereof

PendingCN120795322APolymer sciencePtru catalyst
The invention discloses an organosilicon acrylic acid graft copolymer resin emulsion and a preparation method and application thereof, and the preparation method comprises the following preparation steps: (I) carrying out hydrosilylation reaction on cyclic organosiloxane and an acrylic acid monomer in the presence of a catalyst to form functionalized cyclic oligosiloxane; (II) carrying out ring opening polymerization on the functionalized cyclic oligosiloxane in the presence of an acid catalyst and an emulsifier, and continuously adding a silane coupling agent for reaction to obtain linear organic silicon acrylic acid grafted copolymer resin emulsion; in the step (I), the addition monomer molar ratio Si-H: C = C between the cyclic organosiloxane and the acrylic monomer is (3-6): 1; the cyclic organosiloxane comprises non-hydrogen-containing cyclic siloxane and hydrogen-containing cyclic siloxane, and the mass ratio of the non-hydrogen-containing cyclic siloxane to the hydrogen-containing cyclic siloxane is (1.5-10): 1. According to the scheme, the cross-linking side reaction caused by multi-site substitution in the traditional method can be effectively avoided, the reaction can be complete, and the purity of the linear functionalized cyclic oligosiloxane is improved.
Owner:HANGZHOU XINYU JINGYUAN NEW MATERIALS CO LTD

Preparation method of tetramethyl hydrogen cyclotetrasiloxane

The invention discloses a preparation method of tetramethylhydrocyclotetrasiloxane, which comprises the following steps: mixing linear polymethylhydrosiloxane, hydrogenated terphenyl or a biphenyl-diphenyl ether mixture and an acid catalyst for reaction, carrying out negative pressure distillation on a product, and collecting distillate to obtain a mixture containing methylhydrocyclotetrasiloxane; washing the mixture with water until the mixture is neutral, and separating out an acid water layer; and carrying out primary distillation extraction and rectification purification on the washed mixture to obtain a target product. According to the technical scheme, the linear polymethylhydrosiloxane, the high-temperature-resistant solvent and the acid catalyst are mixed and then are heated under the negative pressure working condition for catalytic cracking to prepare methylhydrocyclosiloxane, and then the target product tetramethylhydrocyclotetrasiloxane is extracted under the negative pressure, so that the yield of tetramethylhydrocyclotetrasiloxane is increased, and the yield of tetramethylhydrocyclotetrasiloxane is increased. The reaction is sufficient, the product quality is stable, the process flow is short, the gelation problem is solved, the process safety is improved, and the method is environment-friendly.
Owner:JIUJIANG RUNHE SYNTHETIC MATERIALS CO LTD

Controllable polymerized gel electrolyte and preparation method thereof

The invention discloses a controllable polymerized gel electrolyte as well as a preparation method and application thereof. The controllable polymerization gel electrolyte is formed by in-situ polymerization of a controllable polymerization gel electrolyte precursor, and the controllable polymerization gel electrolyte precursor comprises the following components in parts by weight: 0.8-2.7 parts of a retarder, 5-27 parts of a cationic polymerization monomer, 15-35 parts of a lithium salt and 4-8 parts of a lithium salt additive; the retarder is a cyclic ether or cyclic siloxane compound with a substituent group containing fluorine atoms. By regulating and controlling the ratio of the retarder to the monomer, the gel process can be controlled, so that the electrolyte is kept in a liquid state at room temperature to be beneficial to storage and infiltration, and a gel structure is formed in situ at a high-temperature aging stage after the battery is assembled. The controllable polymerized gel electrolyte is suitable for a lithium ion battery, and the safety, the cycling stability and the interface compatibility of the battery can be remarkably improved.
Owner:HEFEI GUOXUAN HIGH TECH POWER ENERGY

Polymerization of siloxane polymers

PendingCN121195013APolymer scienceOligomer
The present invention relates to a process for the polymerization of siloxane polymers and copolymers prepared by base-catalyzed ring-opening polymerization of cyclosiloxane oligomers having six siloxane units per ring using a sodium silanol catalyst. The invention also relates to siloxane polymers and copolymers prepared by this process and to the use of these siloxane polymers and copolymers.
Owner:DOW GLOBAL TECHNOLOGIES LLC

Hydrogen-terminated polydimethylsiloxane and preparation method thereof

The invention discloses hydrogen-terminated polydimethylsiloxane and a preparation method thereof. The preparation method comprises the following steps: (1) carrying out mixed reaction on a cyclic siloxane monomer, an end-capping reagent containing a silicon-hydrogen bond and a strong acid catalyst to obtain a first reaction solution containing hydrogen-terminated polydimethylsiloxane; (2) adding ammonia water into the first reaction solution, and carrying out neutralization reaction to obtain a second reaction solution containing hydrogen-terminated polydimethylsiloxane, wherein the temperature of the neutralization reaction is 10-50 DEG C; and (3) carrying out high-temperature vacuum purification treatment on the second reaction liquid to obtain a hydrogen-terminated polydimethylsiloxane purified product, wherein the temperature of the vacuum high-temperature treatment is 100 DEG C or above. According to the preparation method disclosed by the invention, time-consuming and complicated solid-liquid separation steps (such as sedimentation and filtration) in a traditional process can be fundamentally eliminated, so that the production process is simplified, and meanwhile, the prepared hydrogen-terminated polydimethylsiloxane is high in solid content, relatively narrow in molecular weight distribution, good in structural integrity and high in yield. The performance in downstream application (such as textile after-treatment) can be effectively improved.
Owner:GUANGDONG HONGHAO CHEM CO LTD