CN115417991A - Polymerization-termination device and method for continuous production of organopolysiloxane - Google Patents
Polymerization-termination device and method for continuous production of organopolysiloxane Download PDFInfo
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- 229920001296 polysiloxane Polymers 0.000 title claims abstract description 121
- 238000000034 method Methods 0.000 title claims abstract description 96
- 238000010924 continuous production Methods 0.000 title claims description 31
- 238000006116 polymerization reaction Methods 0.000 claims abstract description 158
- KPUWHANPEXNPJT-UHFFFAOYSA-N disiloxane Chemical class [SiH3]O[SiH3] KPUWHANPEXNPJT-UHFFFAOYSA-N 0.000 claims abstract description 64
- -1 cyclic siloxane Chemical class 0.000 claims description 86
- 239000003054 catalyst Substances 0.000 claims description 59
- 230000008569 process Effects 0.000 claims description 57
- 239000003795 chemical substances by application Substances 0.000 claims description 45
- 238000007599 discharging Methods 0.000 claims description 21
- 238000009826 distribution Methods 0.000 claims description 20
- 239000000203 mixture Substances 0.000 claims description 18
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 15
- 230000000694 effects Effects 0.000 claims description 12
- 229920000642 polymer Polymers 0.000 claims description 12
- 239000010703 silicon Substances 0.000 claims description 12
- 229910052710 silicon Inorganic materials 0.000 claims description 12
- WGTYBPLFGIVFAS-UHFFFAOYSA-M tetramethylammonium hydroxide Chemical compound [OH-].C[N+](C)(C)C WGTYBPLFGIVFAS-UHFFFAOYSA-M 0.000 claims description 12
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 9
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- 125000003342 alkenyl group Chemical group 0.000 claims description 6
- 125000002877 alkyl aryl group Chemical group 0.000 claims description 6
- 125000003710 aryl alkyl group Chemical group 0.000 claims description 6
- 125000003118 aryl group Chemical group 0.000 claims description 6
- 125000000547 substituted alkyl group Chemical group 0.000 claims description 6
- 238000005979 thermal decomposition reaction Methods 0.000 claims description 5
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- HUCVOHYBFXVBRW-UHFFFAOYSA-M caesium hydroxide Inorganic materials [OH-].[Cs+] HUCVOHYBFXVBRW-UHFFFAOYSA-M 0.000 claims description 4
- 125000000217 alkyl group Chemical group 0.000 claims description 3
- OBETXYAYXDNJHR-UHFFFAOYSA-N alpha-ethylcaproic acid Natural products CCCCC(CC)C(O)=O OBETXYAYXDNJHR-UHFFFAOYSA-N 0.000 claims description 3
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims description 3
- FSIJKGMIQTVTNP-UHFFFAOYSA-N bis(ethenyl)-methyl-trimethylsilyloxysilane Chemical compound C[Si](C)(C)O[Si](C)(C=C)C=C FSIJKGMIQTVTNP-UHFFFAOYSA-N 0.000 claims description 3
- 125000004432 carbon atom Chemical group C* 0.000 claims description 3
- UQEAIHBTYFGYIE-UHFFFAOYSA-N hexamethyldisiloxane Chemical compound C[Si](C)(C)O[Si](C)(C)C UQEAIHBTYFGYIE-UHFFFAOYSA-N 0.000 claims description 3
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- 239000000463 material Substances 0.000 description 94
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- GKTNLYAAZKKMTQ-UHFFFAOYSA-N n-[bis(dimethylamino)phosphinimyl]-n-methylmethanamine Chemical compound CN(C)P(=N)(N(C)C)N(C)C GKTNLYAAZKKMTQ-UHFFFAOYSA-N 0.000 description 11
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- 229920001971 elastomer Polymers 0.000 description 5
- 229910017053 inorganic salt Inorganic materials 0.000 description 5
- QPFMBZIOSGYJDE-UHFFFAOYSA-N 1,1,2,2-tetrachloroethane Chemical group ClC(Cl)C(Cl)Cl QPFMBZIOSGYJDE-UHFFFAOYSA-N 0.000 description 4
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- 230000014759 maintenance of location Effects 0.000 description 3
- ZQJAONQEOXOVNR-UHFFFAOYSA-N n,n-di(nonyl)nonan-1-amine Chemical compound CCCCCCCCCN(CCCCCCCCC)CCCCCCCCC ZQJAONQEOXOVNR-UHFFFAOYSA-N 0.000 description 3
- 230000001105 regulatory effect Effects 0.000 description 3
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- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
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- GFQRGIBXEJMWJM-UHFFFAOYSA-N [SiH3]O.[K] Chemical group [SiH3]O.[K] GFQRGIBXEJMWJM-UHFFFAOYSA-N 0.000 description 2
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- 125000005372 silanol group Chemical group 0.000 description 2
- YFTHZRPMJXBUME-UHFFFAOYSA-N tripropylamine Chemical compound CCCN(CCC)CCC YFTHZRPMJXBUME-UHFFFAOYSA-N 0.000 description 2
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 2
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- IGYZIZQEEZDUQY-UHFFFAOYSA-N OP(=O)O[SiH3] Chemical compound OP(=O)O[SiH3] IGYZIZQEEZDUQY-UHFFFAOYSA-N 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
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- 239000012530 fluid Substances 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 150000007517 lewis acids Chemical class 0.000 description 1
- 150000007527 lewis bases Chemical class 0.000 description 1
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- 238000012423 maintenance Methods 0.000 description 1
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- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical group CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- HMMGMWAXVFQUOA-UHFFFAOYSA-N octamethylcyclotetrasiloxane Chemical compound C[Si]1(C)O[Si](C)(C)O[Si](C)(C)O[Si](C)(C)O1 HMMGMWAXVFQUOA-UHFFFAOYSA-N 0.000 description 1
- 229920001558 organosilicon polymer Polymers 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
- 230000005501 phase interface Effects 0.000 description 1
- 238000012643 polycondensation polymerization Methods 0.000 description 1
- 239000002861 polymer material Substances 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- IALUUOKJPBOFJL-UHFFFAOYSA-N potassium oxidosilane Chemical compound [K+].[SiH3][O-] IALUUOKJPBOFJL-UHFFFAOYSA-N 0.000 description 1
- 150000003141 primary amines Chemical class 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- SCPYDCQAZCOKTP-UHFFFAOYSA-N silanol Chemical compound [SiH3]O SCPYDCQAZCOKTP-UHFFFAOYSA-N 0.000 description 1
- 229920002379 silicone rubber Polymers 0.000 description 1
- 239000004945 silicone rubber Substances 0.000 description 1
- YIKQLNRXIWIZFA-UHFFFAOYSA-N silyl dihydrogen phosphate Chemical compound OP(O)(=O)O[SiH3] YIKQLNRXIWIZFA-UHFFFAOYSA-N 0.000 description 1
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- 230000002194 synthesizing effect Effects 0.000 description 1
- IMFACGCPASFAPR-UHFFFAOYSA-N tributylamine Chemical compound CCCCN(CCCC)CCCC IMFACGCPASFAPR-UHFFFAOYSA-N 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
- C08G77/04—Polysiloxanes
- C08G77/06—Preparatory processes
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
- C08G77/04—Polysiloxanes
- C08G77/14—Polysiloxanes containing silicon bound to oxygen-containing groups
- C08G77/16—Polysiloxanes containing silicon bound to oxygen-containing groups to hydroxyl groups
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
- C08G77/04—Polysiloxanes
- C08G77/20—Polysiloxanes containing silicon bound to unsaturated aliphatic groups
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
- C08G77/42—Block-or graft-polymers containing polysiloxane sequences
- C08G77/442—Block-or graft-polymers containing polysiloxane sequences containing vinyl polymer sequences
Abstract
The present invention relates to a polymerization-terminating apparatus and method for continuously producing organopolysiloxane. The apparatus of the invention comprises directly connected reactors 1 and 2, in which the polymerization of the siloxane is carried out with devolatilization in reactor 1 and the polymerization is terminated with deep devolatilization in reactor 2. The device of the invention has simple structure, improves the polymerization and termination efficiency and realizes controllable polymerization. The produced organopolysiloxane has good quality, including wide viscosity range of the prepared product, low volatile content, low impurity content, high transparency, high thermal stability and the like.
Description
Technical Field
The invention relates to the technical field of organopolysiloxane production.
Background
Linear organopolysiloxane is an organosilicon polymer with-Si-O-Si-bond as the main chain, which is a basic polymer material in the organosilicon industry. A great number of organosilicon downstream formula products with different functions can be obtained by adding various auxiliary agents, fillers and the like into the linear organopolysiloxane. The industrial production of such linear organopolysiloxanes is generally obtained by: heating octamethylcyclotetrasiloxane (D4) or dimethyl siloxane ring (DMC) as raw materials to a polymerization temperature (higher than 80 ℃), performing a polymerization chain growth-chain transfer-chain termination process under the catalysis of strong acid or strong base, keeping the process at the temperature for a period of time, and adding a terminator to terminate the reaction after the polymerization is regulated to the required viscosity. The above process is a catalytic equilibrium process, about 10-16% of cyclosiloxane exists in the final product, and small molecular low-boiling-point substances are removed through a high-temperature decompression process to obtain the target product. Various Bronsted acids and bases and Lewis acids and bases can be used as catalysts in the siloxane polymerization process.
Polymerization reactions can be classified into ring-opening polymerization and condensation polymerization according to the kind of polymerization. For example, chinese patent CN102093651B proposes that potassium hydroxide or tetramethyl ammonium hydroxide reacts with dimethyl siloxane ring bodies respectively to prepare catalysts A and B, A, B is mixed and refined according to a certain proportion to obtain a composite catalyst, and the composite catalyst can efficiently catalyze the preparation of 107 glue from high ring bodies. CN107216456A discloses that a mixture of polydimethylsiloxane ring bodies and linear bodies is used as a raw material, a polymer containing silicon hydroxyl groups is used as an end-capping agent, the silicon hydroxyl group-capped polydimethylsiloxane is obtained under the catalysis of caged phosphazene superbase, and finally an acidic substance is added to terminate the reaction.
The process flow of siloxane polymerization can be roughly classified into three types, a batch method, a semi-continuous method and a continuous method, each using a reaction apparatus of different forms.
Batch process, i.e. batch process in a polymerization reactor, is the most commonly used process, and before the polymerization starts, various materials including cyclic siloxane or linear siloxane, an end-capping agent and a catalyst are required to be uniformly mixed in the reactor and heated from normal temperature to reaction temperature (80-180 ℃). Limited by the stirring efficiency of the paddle reaction kettle, long time is needed for uniform mass and heat transfer; in the later stage of the reaction, the mass and heat transfer process becomes more difficult because the product has certain viscosity, and in order to ensure that all materials are fully reacted and reach a polymerization equilibrium state, the retention time of the materials in the reaction kettle needs to be prolonged, so the polymerization reaction time is usually more than 3-4 h.
For the polymerization process of siloxane, the batch process has a disadvantage of low reaction efficiency. Under the existence of a commonly used alkaline catalyst such as potassium hydroxide, a terminator needs to be added into the reaction kettle in time after the polymerization is finished to terminate the catalytic process, and meanwhile, the pH value of the product is neutralized. Also, due to the inefficient stirring, a longer time is required to achieve sufficient dispersion after the addition of the terminating agent, which increases the process time. Even so, for organosilicon high-viscosity products, sufficient dispersion effect cannot be realized, that is, uniformity and instantaneity of a reaction system cannot be ensured, so that indexes such as molecular weight, viscosity and volatility of a polymerization product are not controlled and deviate from specification requirement ranges. Therefore, in order to achieve a better termination (neutralization) effect, the terminating agent is generally in large excess over the catalyst. However, the inorganic salts generated by the termination reaction are also more and remain in the system, resulting in a decrease in product purity, stability and transparency.
The batch process also has the disadvantage of poor devolatilization. The polymerization reaction is generally an equilibrium reaction, and after the reaction is finished, a large amount of low-boiling-point substances to be removed exist in the product. Due to the accumulation of products from bottom to top in the reaction kettle, the thickness is large, an effective film forming mechanism is lacked to increase the gas-liquid mass transfer area, and particularly when the viscosity of the organosilicon product is large, the devolatilization process becomes more difficult. In addition, the temperature difference formed in the upper space of the reaction kettle easily enables the vaporized low-boiling-point substances to be condensed and refluxed again, even if inert gases such as nitrogen and the like are blown from the bottom to carry out vapor, the effect is limited due to insufficient bubble dispersion, easy aggregation and the like, and on the contrary, the environmental pollution and the like can be caused due to the difficult tail gas recovery. In addition, the boiling point of the low-boiling-point substances of the ring body is high, the temperature and the pressure need to be increased and reduced in the devolatilization process, the heating temperature is usually more than 200 ℃, local overheating is easily caused by long-time high temperature, and the product deterioration, crosslinking and the like can be caused in a stirring dead zone to pollute the final product. In order to make the volatile content of the organosilicon product about 1 percent, more power is needed, and the devolatilization time is as long as 4 to 10 hours. This indicates that the batch process has a disadvantage of low reaction efficiency and poor devolatilization effect. In addition to the above-mentioned drawbacks, the products produced in different batches by the batch process inevitably have quality differences, and the quality is difficult to control accurately.
The semi-continuous process equipment is usually formed by serially connecting a plurality of larger polymerization reaction kettles, and can separately carry out the polymerization process, the termination reaction and the devolatilization process, thereby saving time and improving the production capacity. However, inevitably, a larger production space and a more complicated operation procedure are required, and when the viscosity of the product is high, the transfer of materials between different reaction kettles becomes extremely difficult and energy-consuming. Other drawbacks of batch processes, such as broad molecular weight distribution of the product due to uneven stirring, are still present in semi-continuous processes.
The continuous process generally adopts a tubular reactor with strong convection characteristic as a polymerization reaction device, but can only produce products with the molecular weight of about 60-80 ten thousand at most, and if organic silicon products with higher molecular weight are produced, the back mixing caused by huge viscosity difference between raw materials and products is difficult to overcome, namely, the plug flow cannot be maintained, and then the uniformity of the molecular weight becomes very poor. The high viscosity product requires a large pressure drop to maintain a certain flow rate in the tubular reactor, increasing power consumption. In addition, after the reaction is finished, an additional reactor is still needed for terminating the reaction and finishing the low volatile matter removal process, the attached equipment is various, and the investment is high.
In summary, although the synthesis scale of linear or cyclic organopolysiloxanes is gradually increased with the development of the silicone industry, various defects of the conventional processes and apparatuses are still the main reasons for the limitation of low energy consumption, low emission, low pollution and high efficiency production. Moreover, the organopolysiloxane prepared by the prior art process hardly has excellent quality, and has the defects of narrow viscosity range of products, difficult accurate control of viscosity, uneven molecular weight distribution, higher volatile components, poorer thermal stability and long-term storage stability, higher content of inorganic salt impurities, poor transparency and the like in various aspects, so that various performances and stability in the application of downstream formula products are greatly influenced.
Although the prior art has proposed several methods for producing organopolysiloxanes, there are various drawbacks which are difficult to solve.
US4551515A discloses a process for continuously producing organosilicon crude rubber, which comprises mixing siloxane ring bodies with chain end capping agents, preheating to above 130 ℃, adding potassium silanolate as a catalyst, allowing the mixture to enter a first static prereactor for preliminary polymerization, allowing the obtained preliminary polymerization product to continue to enter a second static prereactor for polymerization, allowing the viscosity of the discharged material to be about 2,000,000cP, allowing the discharged material to enter a single-screw Buss-Condux device with a plurality of kneading units for deep polymerization, removing low-boiling substances, injecting silyl phosphate at the rear end of the single screw to terminate the reaction, and finally obtaining a crude rubber product with uniform molecular weight distribution, wherein the subsequent application performance is consistent with that of polymers produced by batch methods.
However, this process can only produce silicone polymers with viscosities above 500,000cp, probably due to the tendency of a single screw configuration to leak, resulting in failure to carry low viscosity materials. And before the reaction materials enter the screw reactor, the reaction materials need to be premixed and preheated, and then are polymerized by two static mixers connected in series to reach a certain viscosity, and the complexity of the equipment is increased due to the single-screw structure. In addition, the single-screw kneading effect is poor, the surface updating rate of the materials in the exhaust area is low, the gas-liquid mass transfer effect is poor, and the volatile components of the obtained product are high.
US6221993B1 discloses a process for the continuous production of silicone polymers which can be polymerized in the presence of a catalyst phosphazene base and a small amount of water as a promoter in a twin screw extruder reaction zone, starting from linear siloxanes containing terminal silicon hydroxyl groups (polycondensation), or cyclic siloxanes (ring opening polymerization), or mixtures of the two, respectively, with a high yield of the initial polymerization product; continuing to convey the initial polymerization product to a neutralization zone of the twin screw extruder for intimate mixing with a terminating agent, a silyl phosphonate, to terminate the polymerization reaction; and continuously feeding the material leaving the neutralization zone into a Z pulp kneader or a stripping zone of a double-screw extruder, and heating and decompressing to remove low-boiling-point substances. The final product has less than 1% of volatile components, and has extremely high stability, and the decomposition temperature is as high as 567 ℃.
The above process separately performs polymerization, termination and devolatilization processes in different zones of an extruder, resulting in a more restrictive profile of each functional zone. And the length-diameter ratio of the screw is limited, so that the complete completion of each section of process flow cannot be ensured. The concentration of the different functional blocks on one extruder also increases the risk of malfunctions and malfunctions in the continuous production process, and moreover, only silicone polymers having a molecular weight of 90,000 or more are prepared in the examples thereof, and the range of applicable products is single and is not suitable for the production of organopolysiloxane products having lower viscosity.
CN111574714B discloses a polysiloxane production method, wherein polymerization is completed by a polymerization type double screw extruder, termination reaction is completed by a static mixer, and devolatilization is completed by a falling strip devolatilizer and another devolatilization type double screw extruder. The overall design of the equipment is bloated, and the risk of failure in the continuous production process is greatly increased. Furthermore, static mixers have difficulty in achieving real-time control of product viscosity. When the static mixer is used for treating the termination reaction of the high-viscosity material, because the flow values of the high-viscosity material and the terminating agent are greatly different and the viscosity difference of the two types of fluids is also large, the two types of materials are difficult to be uniformly mixed within the static mixing residence time of usually ten seconds to several minutes, and the neutralization efficiency is low, namely the internal reaction of the high-viscosity material cannot be completely terminated in the process; and the high-viscosity material contains a certain amount of low-boiling by-products, so that the viscosity difference between the high-viscosity material and the final product is large, and the viscosity/molecular weight of the product cannot be regulated and controlled in real time. Although this patent mentions that lower viscosity polysiloxanes can be prepared, it is not suitable in industrial practice for the preparation of low viscosity products due to the use of a falling strand devolatilizer. In addition, the use of static mixers and falling bar devolatilizers is not suitable for seamless switching of production lines, and various types of organopolysiloxanes cannot be produced. In addition, the polymerization, termination and devolatilization processes are carried out in separate equipment, which increases the overall process time.
CN205115352U discloses a device for devolatilizing ultra-high molecular weight polysiloxane, wherein a perforated plate, a conical surface body with holes on the front and back surfaces, and the like are arranged in a tank body and are respectively arranged at different spatial positions, so that the ultra-high molecular weight polysiloxane can be divided into strip-shaped colloid flows, the specific surface area is increased, the retention time of the ultra-high molecular weight polysiloxane in the device is prolonged, the mixing process is enhanced, and the rapid devolatilization is facilitated. After the ultrahigh molecular weight polysiloxane is treated for 2 to 3 hours, a product with the volatile content of below 0.8 percent can be obtained, and the uniformity of the product is improved.
Although this patent can achieve a low volatile content, the devolatilization process time still takes more than several hours. The principle of the polymer devolatilization process is that a gas-liquid phase interface is generated by increasing the surface area of a high-viscosity material for mass transfer, and the interface is updated in multiple mixing processes, so that the gas-liquid mass transfer driving force is increased. But is limited by the larger volume of the formed ribbon colloid, the smaller specific surface area and the slow surface renewal rate generated by passive mixing, so that the devolatilization treatment time is longer.
CN102140170B discloses a new process for synthesizing permethyl silicone oil with molecular weight of 55,000-70,000. After the reaction is terminated, the material is dispersed into filaments through a pattern plate, and then low molecular impurities are removed in a flash evaporation manner in a devolatizer, so that the devolatilization process can be completed quickly. However, the document does not mention the value of the volatile content in the final product.
CN103435808A proposes that after dehydration treatment of siloxane ring bodies, the siloxane ring bodies are heated to a predetermined temperature through a preheater, fed into an online mixer together with a catalyst and uniformly stirred, fed into a polymerization cylinder to be continuously heated to a reaction temperature, reacted for 1-1.5h, then fed into a degrader to react with water vapor for degradation, and finally fed into a double-screw rubber outlet machine to remove water vapor and low-boiling products and decompose the catalyst, thereby continuously producing 107 rubber. The disadvantage of this document is that the volatile component is still high, and the twin-screw gum discharging machine only plays a role in devolatilization in the process, and the early polymerization process is still similar to the traditional process, which takes a long time.
CN205241587U proposes to carry out polymerization reaction in a reaction kettle, then the material enters a static mixer for removing low, then enters a counter-rotating conical twin-screw extruder, the discharged material enters a parallel vacuum double-screw extruder for secondary devolatilization, and the volatile component of the prepared organopolysiloxane with the molecular weight of 100-200 ten thousand is lower than 0.6 percent. The disadvantages are that in order to achieve lower volatile components, a plurality of sets of equipment are used in series, the functions are redundant, and the time consumption is still long.
The above prior arts have explored the polymerization reaction, termination reaction and devolatilization process in the industrial production of organopolysiloxane, respectively, but all have various problems yet to be solved. Although the patent US6221993B1 concentrates polymerization, termination and devolatilization on one device, it can only prepare products with molecular weight of more than 90,000, and the volatility of the final product is about 1%, and it is still difficult to meet the requirements of various downstream formulation applications on siloxane polymers at present.
There is still a need for a process for the efficient continuous production of organopolysiloxanes which addresses the various deficiencies and drawbacks of the prior art as noted above.
The invention aims to provide a polymerization-termination device for continuously producing organopolysiloxane and a method thereof. The method achieves various improvements.
1. The device overcomes the defects of complex and tedious structure, low space-time efficiency, high energy consumption, low productivity and the like of the traditional process device, and has simplified structure and good process repeatability.
2. The device has the advantages of strong distribution and mixing capability, easy mass and heat transfer, easy feeding and discharging and high production efficiency.
3. The device can realize effective control of termination reaction, thereby obtaining the expected product viscosity range and realizing accurate control of the molecular weight/viscosity of the product.
4. Can prepare organopolysiloxane products with wider viscosity range, including various low-viscosity silicone oils, high-viscosity silicone oils, crude silicone rubber and the like, so as to meet the requirements of downstream generation. The viscosity of the produced organopolysiloxane ranges from 300 mPas to 20,000,000mPas (cP).
5. The quality of the organopolysiloxane product is improved, and the product has the advantages of low volatile component, uniform molecular weight distribution, low inorganic salt content, good transparency and high thermal stability. More importantly, a narrow molecular weight distribution can be maintained over a very wide range of product viscosities.
6. The devolatilization time is short.
Disclosure of Invention
The invention relates to a polymerization-terminating device for the continuous production of organopolysiloxanes, comprising:
a reactor 1 for carrying out a polymerization reaction of siloxane;
and the feed inlet of the reactor 2 is connected with the discharge outlet of the reactor 1 and is used for terminating the polymerization reaction.
In a preferred embodiment, reactor 1 is devolatilized while the polymerization is being carried out, and/or reactor 2 is devolatilized while the polymerization is being terminated.
In a preferred embodiment, the organopolysiloxanes produced have a viscosity in the range from 300 to 20,000,000mPaS, preferably from 1,000 to 10,000mPaS, more preferably from 100,000 to 1,000,000mPaS, even more preferably from 3,000,000 to 10,000,000mPaS. More particularly, the viscosity range of the produced organopolysiloxane is selected from 300, 1000, 2000, 3000, 5000, 10,000, 20,000, 50,000, 80,000, 100,000, 300,000, 500,000, 1,000,000, 3,000,000, 5,000,000, 10,000,000, 15,000,000, 20,000,000mpa · S or any subinterval there between.
In a preferred embodiment, the organopolysiloxanes produced have a volatile content of less than 0.5%, preferably less than 0.3%.
In a preferred embodiment, the organopolysiloxane produced has a narrow molecular weight distribution, preferably from 1.4 to 2.3, more preferably from 1.5 to 2.0.
In a preferred embodiment, the organopolysiloxanes produced have a low content of inorganic salts, preferably <11ppm, more preferably <0.1ppm.
In a preferred embodiment, the organopolysiloxanes produced have a high thermal stability, preferably a thermal decomposition temperature of 380 ℃ to 510 ℃ and more preferably a thermal decomposition temperature of 385 ℃ to 470 ℃.
In a preferred embodiment, the reactor 1 is a co-or counter-rotating twin-screw extruder 1 and the reactor 2 is a co-or counter-rotating twin-screw extruder 2.
In a preferred embodiment, the front end of the reactor 2 is provided with a terminator feeding port.
In a preferred embodiment, the outlet of the reactor 1 is directly connected to the inlet of the reactor 2, preferably in a straight line or perpendicularly to each other or at some other angle.
In a preferred embodiment, wherein the screw diameter of the twin-screw extruder 1 is 36 to 360mm, preferably 120 to 240mm.
In a preferred embodiment, wherein the screw diameter of the twin-screw extruder 2 is from 36 to 240mm, preferably from 80 to 240mm.
In a preferred embodiment, wherein the screw speed of the twin-screw extruder 1 is from 1 to 200rpm, preferably from 1 to 150rpm, more preferably from 50 to 120rpm.
In a preferred embodiment, wherein the screw speed of the twin-screw extruder 2 is from 1 to 600rpm, preferably from 1 to 150rpm, more preferably from 60 to 150rpm.
In a preferred embodiment, wherein the temperature of the reactor 1 is in the range of 20 to 180 ℃, preferably 110 to 150 ℃, more preferably 80 to 110 ℃.
In a preferred embodiment, wherein the temperature of the reactor 2 is in the range of 20 to 180 ℃, preferably 100 to 170 ℃, more preferably 160 to 170 ℃.
In a preferred embodiment, wherein the pressure in the reactor 2 is from 0 to 50kPa, preferably from 0 to 5kPa.
In a preferred embodiment, the starting materials for the production of the organopolysiloxanes may be linear siloxanes, cyclic siloxanes or mixtures of the two.
In a preferred embodiment, for linear siloxane feedstocks, the temperature of reactor 1 is from 80 to 110 deg.C, the speed of reactor 1 is from 50 to 120rpm, the temperature of reactor 2 is from 160 to 170 deg.C, and the speed of reactor 2 is from 60 to 150rpm, whereby organopolysiloxanes having a broader molecular weight/viscosity range, such as those having a viscosity of from 20,000mPa S to 20,000,000mPa S, can be prepared. More importantly, a narrow molecular weight distribution, such as 1.5 to 1.8, can be maintained over a very wide molecular weight/viscosity range.
The invention also relates to a polymerization-termination method for the continuous production of organopolysiloxanes using the apparatus according to the invention, comprising the following steps:
a) Sequentially adding siloxane including linear siloxane or cyclic siloxane or a mixture of the linear siloxane and the cyclic siloxane, an end-capping agent and a catalyst into a reactor 1 to perform polymerization while performing partial devolatilization, so as to obtain an initial product of which the polymerization reaction is not terminated;
b) The initial product of the polymerization reaction which has not been terminated is extruded from reactor 1 and fed to reactor 2 where it is thoroughly mixed with a terminating agent to effect termination of the polymerization reaction while undergoing deep devolatilization to give an organopolysiloxane product.
In a preferred embodiment, the linear or cyclic siloxanes in step a) have the following repeating structural unit- [ SiR ] 1 R 2 -O-] n Wherein n is 1 to 500, preferably 2 to 100, more preferably 3 to 20 1 、R 2 Is H or optionally substituted alkyl, alkenyl, aryl, alkaryl or aralkyl groups, or the like.
In a preferred embodiment, the endcapping agent is selected from the group consisting of divinyltetramethyldisiloxane, hexamethyldisiloxane, represented by the general formula R 3 -[SiMe 2 -O-] n -SiMe 2 R 3 Linear polymers and mixtures thereof of formula (I) wherein n is 1 to 20 3 Is H, OH or an optionally substituted alkyl, alkenyl, aryl, alkaryl, or aralkyl group.
In a preferred embodiment, wherein the catalyst is selected from potassium hydroxide, sodium hydroxide, cesium hydroxide, lithium hydroxide, tetramethylammonium hydroxide, phosphazenes, or one or more of the silicon alkoxides of the foregoing.
In a preferred embodiment, the terminator is selected from one or more ofThe method comprises the following steps: phosphoric acid, acetic acid, octanoic acid, of the formula R 4 3 Tertiary amines of N of the formula R 4 2 Secondary amine of NH of the formula R 4 NH 2 Wherein R is 4 Alkyl groups having 2 to 10 carbon atoms, silazanes, or silicon alkoxides of the foregoing.
In one embodiment of the present invention, the organopolysiloxanes produced include a, ω -hydroxy-terminated 107 gum, trimethylsiloxy-terminated polydimethylsiloxane, bisvinyl-terminated or methyl-terminated polydimethylsiloxane having a vinyl group in the middle segment, polydimethylsiloxane having a Si-H bond in the terminal, methyl-or Si-H bond-terminated polydimethylsiloxane having a Si-H bond in the middle segment, and the like.
The present invention provides an efficient polymerization-termination apparatus and method for continuously and efficiently producing organopolysiloxane, which solves the above-mentioned problems of the prior art.
The device has strong distribution and mixing capability, is easy for mass and heat transfer, ensures that the materials uniformly and fully participate in the reaction, is easy for feeding and discharging, and has high production efficiency. The polymerization and termination reaction efficiency can be effectively improved. Meanwhile, in the process, due to the fact that stirring is sufficient, a large amount of liquid films are generated through stretching and shearing, the surface updating speed is high, and the large mass transfer area is beneficial to fast and efficiently synchronously removing volatile components. The device and the method can be used for continuously producing various types of organopolysiloxane, and the viscosity range is between 300 and 20,000,000cP and is accurately controllable. In addition, the obtained product has narrow molecular weight distribution, low content of inorganic salt impurities, high thermal stability and less than 0.5 percent of volatile components. More importantly, a narrow molecular weight distribution can be maintained over a very wide molecular weight/viscosity range.
The polymerization-termination device for continuously producing the organopolysiloxane has low complexity, only consists of two reactors (such as a double-screw extruder) which are directly connected, saves production space and is convenient for production control. All the processes involved in the organopolysiloxane production process can be carried out continuously and rapidly in this plant, greatly increasing the space-time efficiency of the plant. The material is successively subjected to polymerization and optionally partial devolatilization in reactor 1, termination and deep devolatilization in reactor 2. The two reactors are directly connected, the material transfer time can be almost kept, the efficiency is higher, the termination reaction is more timely, and the real-time and accurate regulation and control of the molecular weight and the viscosity of the polymer are facilitated. Compared with the prior art, the process can realize synchronous devolatilization, save the additional time-consuming and energy-consuming devolatilization process and greatly save the production time.
The device of the invention can prepare linear polysiloxane with extremely wide viscosity range. On the one hand, polysiloxanes with low viscosity can be prepared because of the simple connection of the devices and the low tendency to leak. On the other hand, owing to the high-efficiency stirring of the twin-screw extruder, mass and heat transfer can be effectively carried out and back mixing can be avoided, so that polysiloxanes with high viscosity can also be prepared. More importantly, the device of the present invention can rapidly act as a terminator, thereby achieving precise control of product viscosity/molecular weight.
In addition, the device of the invention can not leave deposition materials in the equipment, can directly switch production lines without polluting products, and is convenient for preparing various types of organopolysiloxane. The organopolysiloxane produced according to the apparatus and method of the present invention has the following excellent qualities at the same time: small fluctuation of molecular weight/viscosity, uniform molecular weight distribution, extremely low volatile component, low content of inorganic salt impurities, good thermal stability and long-term storage stability.
If a conventional screw is added to a static mixer and other equipment, the sealability may be somewhat lowered due to the connection of multiple pipes, and the twin screw in the static mixer cannot achieve sealing and vacuum maintenance when a low-viscosity material is charged, and cannot satisfy the preparation conditions of a low-viscosity polysiloxane. On the contrary, in the invention, two double-screw reactors are directly connected in series, so that the pipeline connection is reduced, an additional sealing interface is avoided, the sealing property and high vacuum degree can be kept in the whole production process, and the preparation of low-viscosity organopolysiloxane is facilitated.
The invention does not adopt a static mixer which is difficult to accurately control the viscosity of the product in real time, but utilizes the excellent stirring capability of the double screws to quickly and fully mix and react materials, the catalyst and the terminator, so that the polymerization reaction is controllable in real time, and polymers with various viscosities can be accurately obtained.
In one embodiment of the invention, the screw extruder for siloxane high-efficiency polymerization and the screw extruder for high-efficiency termination of polymerization are directly connected in series, so that flexible combination of reactors with different functions is realized, the production space is saved, and the material transfer time is short.
In general, the polymerization-terminating apparatus and method for continuously producing organopolysiloxane according to the present invention have the following advantages.
a) The applicability is wide: the whole set of device has excellent distribution and mixing capability when preparing various organopolysiloxanes with low viscosity, high viscosity or raw rubber and the like, the heat and mass transfer process is rapid and uniform, various reaction materials can be uniformly mixed, the reaction is complete in a short retention time, the axial direction is stable plug flow, no back mixing phenomenon occurs, the prepared polymer is uniformly distributed, and the device is suitable for continuous production;
b) The controllability is strong: the initial polymerization product of reactor 1 is directly fed to reactor 2 for terminating the reaction without intermediate residence time; by utilizing the excellent stirring capacity of the double screws, materials are quickly and fully mixed and reacted with the catalyst and the terminator, so that the polymerization reaction is controllable in real time, and polymers with various viscosities can be accurately obtained;
c) The process is excellent: during the stirring process of the double-screw extruder, a large number of extremely thin liquid films can be formed through strong stretching and shearing actions, the specific surface area of a product is increased, a gas-liquid interface is formed to transfer mass, and then low-boiling-point substances are discharged, and the liquid films can be continuously mixed with materials in the cavity to form a new liquid film, namely, the surface updating rate is high, the gas-liquid mass transfer process is enhanced, and the final devolatilization effect is excellent;
d) Function modularization: the two double-screw extruders are respectively used for polymerization reaction, termination reaction and devolatilization process, so that each process can be conveniently and respectively regulated and controlled, simple parameter change is realized, and products with different polymerization effects and low devolatilization effects can be obtained.
Drawings
FIG. 1 is a schematic view of a polymerization-terminating apparatus and method for continuously producing organopolysiloxane according to one embodiment of the present invention.
Detailed Description
As shown in FIG. 1, the polymerization-terminating apparatus for continuous production of organopolysiloxane of the present invention comprises:
a reactor 1 for efficiently performing a polymerization reaction of siloxane;
a reactor 2 directly connected to the discharge port of the reactor 1 and for efficiently terminating the polymerization reaction;
in certain embodiments of the present invention, reactors 1 and 2, respectively, used in the polymerization-termination apparatus of the present invention may be twin screw extruders, which may alternatively be other types of continuous paddle extrusion type devices. In certain embodiments of the invention, the twin screw extruder 1 has a feed port, a vent port, a discharge port, and a vent port. The feed inlet of the double-screw extruder 1 is connected with various raw material storage tanks. In certain embodiments of the invention, the twin screw extruder 1 is a co-or counter-rotating twin screw extrusion reactor. In certain embodiments of the present invention, the twin-screw extruder 1 used for polymerization is fed in the following manner: the feed is from the head of the extruder 1 and the discharge is from the discharge port of the barrel at the tail of the screw, and the discharge port is directly connected with the twin-screw extruder 2 for terminating the polymerization reaction. The barrel of the twin-screw extruder 1 is closed, thereby establishing a high vacuum environment to enhance the sealability of the reactor 1.
In certain embodiments of the invention, the twin-screw extruder 1 comprises:
a twin screw extruder body; a feed inlet is arranged at the barrel body at the head part of the screw rod of the double-screw extruder, a discharge outlet is arranged at the barrel body at the tail part of the screw rod, and the discharge outlet is directly connected with the double-screw extruder 2;
the structure of the twin-screw extruder body is not particularly limited in the present invention and may be any combination of various different barrels, screws and screw elements known to those skilled in the art.
In certain embodiments of the invention, the twin screw extruder body has a screw diameter of 36 to 240mm and a screw length to diameter ratio of 18 to 60. Preferably, the screw diameter of the twin-screw extruder body is 240mm, and the length-diameter ratio of the screw is 28.
In some embodiments of the present invention, a linear siloxane, a cyclic siloxane or a mixture of the two, an end capping agent and a catalyst are charged into the feed port of the twin-screw extruder 1 as reaction raw materials, after the raw materials are mixed and heated uniformly in the twin-screw extruder 1, the materials are gradually conveyed forward and simultaneously the siloxane polymerization reaction occurs as the twin-screw is stirred, and then the initial materials after the polymerization reaction are discharged from the discharge port of the twin-screw extruder 1 and directly enter the twin-screw extruder 2. Namely, under the working state, the reaction raw materials enter from the feed inlet of the double-screw extruder 1 body to generate polymerization reaction, and the materials after the polymerization reaction are discharged from the discharge outlet.
The twin-screw extruder 1 further comprises a devolatilization chamber. The devolatilization chamber is arranged on the cylinder body of the double-screw extruder 1 body. When the forward material passes through the cylinder section provided with the devolatilization chamber, the material is devolatilized under the vacuum condition, and the low-boiling-point substances are discharged through an exhaust port of the devolatilization chamber. The devolatilized material is discharged from a discharge port of the twin-screw extruder 1, and the volatile matter is discharged from an exhaust port of the devolatilization chamber.
The reactor 2 used in the polymerization-terminating apparatus of the present invention is more commonly in the form of a twin-screw extruder. In the embodiment of the present invention, the twin-screw extruder 2 is provided with a feed port, a terminator injection port, a discharge port, and a vent port. The feed inlet of the double-screw extruder 2 is directly connected with the discharge outlet of the reactor 1. In certain embodiments of the invention, reactor 2 is a devolatilizing twin screw extruder such as a co-or counter-intermeshing twin screw extruder.
In certain embodiments of the invention, reactor 2 is fed in the following manner: feeding from the joint of the tail of the screw and the reactor 1, and discharging from the barrel at the head of the screw. The barrel of the reactor 2 is a closed barrel, whereby a high vacuum environment can be established to facilitate improved screw tightness.
In certain embodiments of the present invention, the devolatilizing twin screw extruder 2 comprises:
a twin screw extruder body; a feed inlet directly connected with the reactor 1 is arranged at the barrel at the tail part of the screw, and a discharge outlet is arranged at the barrel at the head part of the screw;
a devolatilization chamber arranged on the barrel body of the devolatilization type double-screw extruder body.
The present invention is not particularly limited to the configuration of the twin-screw extruder body, and may include various barrels, screws, and screw elements, and any combination thereof, as are well known to those skilled in the art. In certain embodiments of the invention, the twin screw extruder body has a screw diameter of 36 to 240mm and a screw length to diameter ratio of 36 to 60. Preferably, the screw diameter of the twin-screw extruder body is 55mm, and the length-diameter ratio of the screw is 38.
In the working state, the reaction material discharged from the discharge port of the reactor 1 enters from the feed port of the reactor 2 and is uniformly mixed with the terminating agent, thereby terminating the polymerization reaction. Meanwhile, the material forms an extremely thin liquid film with extremely large specific surface area under the action of strong stretching and shearing, so that the low-boiling-point substances can be conveniently removed by gas-liquid interface mass transfer. The continuous stirring can form a new liquid film, the interface renewal rate is high, and the mass transfer power in the low-boiling removal is enhanced, so that the devolatilized organic polysiloxane product is discharged from the discharge hole of the reactor 2.
The devolatilization twin screw extruder also includes a devolatilization chamber. The devolatilization chamber is arranged on the cylinder body of the double-screw extruder body. When the forward material passes through the cylinder section provided with the devolatilization chamber, the enhanced devolatilization is carried out under the vacuum condition, and the volatile components are discharged through an exhaust port of the devolatilization chamber. The devolatilized organopolysiloxane product is discharged through the discharge port of the reactor 2, and the volatiles are discharged through the exhaust port of the devolatilization chamber of the reactor 2.
The present invention also relates to a method for continuously producing an organopolysiloxane using the above polymerization-termination apparatus, comprising the steps of:
a) Charging a siloxane comprising a linear siloxane, a cyclic siloxane or a mixture of both, together with an endcapping agent and a catalyst, into reactor 1 through a feed port;
b) The feeds are rapidly mixed and uniformly heated in the reactor 1 to effect the polymerization of the siloxane;
c) Feeding the initial polymerization product exiting the reactor 1 to a reactor 2 and rapidly mixing with a terminator to terminate the polymerization reaction;
d) The material is subjected to deep devolatilization in the reactor 2 to obtain the organopolysiloxane.
In certain embodiments of the present invention, the siloxane used as a starting material may be of the formula- (SiR) 1 R 2 -O-) n Wherein n is 1 to 500, preferably n is 2 to 100, or a cyclic siloxane or a mixture of the two 1 、R 2 Is H or optionally substituted alkyl, alkenyl, aryl, alkaryl or aralkyl, etc. In certain embodiments of the invention, the siloxane feedstock is fed in an amount of 50 to 400kg/h, preferably 200kg/h, more preferably 150kg/h.
In certain embodiments of the invention, the catalyst is one or more catalysts selected from the group consisting of: potassium hydroxide, sodium hydroxide, cesium hydroxide, lithium hydroxide, tetramethylammonium hydroxide, phosphazene catalysts, or silicon alkoxides of the above. In certain embodiments of the invention, the catalyst solution is fed in an amount of 0.01 to 2kg/h. In certain embodiments, the catalyst solution is fed in an amount of 0.05 to 1kg/h.
In certain embodiments of the present invention, the endcapping agent is selected from the group consisting of divinyltetramethyldisiloxane, hexamethyldisiloxane represented by the general formula R 3 -[SiMe 2 -O-] n SiMe 2 R 3 Linear polymers and mixtures thereof of formula (I) wherein n is 1 to 20 3 Is H, OH or an optionally substituted alkyl, alkenyl, aryl, alkaryl, or aralkyl group. In certain embodiments of the invention, the capping agent is fed in an amount of 0.2 to 15kg/h. In certain embodiments, the capping agent is fed in an amount of 1 to 10kg/h.
The feed is polymerized in a reactor 1, such as a twin-screw extruder, to give a polymerized initial product.
In certain embodiments of the invention, the screw barrel temperature of reactor 1 is 23 to 200 ℃. In certain embodiments, the screw barrel temperature of the reactor 1 is from 100 to 150 ℃. In certain embodiments of the invention, the screw speed of reactor 1 is between 10 and 600rpm. In certain embodiments, reactor 1 is a polymeric twin screw extruder with a screw speed of 200rpm. In certain embodiments of the invention, the polymerization reaction in reactor 1 is conducted under a vacuum of from 50 to 50,000Pa.
In certain embodiments of the invention, the terminating agent is phosphoric acid, acetic acid, octanoic acid, a compound of the formula R 4 3 N tertiary amine of the formula R 4 2 Secondary amine of NH of the formula R 4 NH 2 Of primary amine, R 4 Is one or more of alkyl with 2-10 carbon atoms, silazane or silicon alkoxide of the above substances. In certain embodiments of the invention, the amount of terminator solution fed is from 0.02 to 5kg/h.
The polymerized initial product is extruded from reactor 1 and fed to reactor 2 (e.g., twin-screw extruder 2) where it is mixed uniformly with a terminating agent to terminate the polymerization reaction. At the same time, the material in the reactor 2 is deeply devolatilized under stirring, high vacuum and high temperature to discharge low boiling point substances, and an organopolysiloxane product is obtained.
In certain embodiments of the invention, the screw section barrel temperature of reactor 2 is 20 to 180 ℃, preferably, the screw section barrel temperature is 120 ℃. In certain embodiments of the invention, the screw speed of the reactor 2 is between 10 and 600rpm, preferably the screw speed is 100rpm. In certain embodiments of the invention, the vacuum in reactor 2 is in the range of 100 to 10,000Pa.
The present invention is not particularly limited with respect to the source of the feed to the above-mentioned reactor 1, and may be derived from commercially available products.
The feed comprising siloxane, blocking agent and catalyst was fed to the feed port of reactor 1 via a metering pump and charged therein. Under vigorous stirring kneading, the feeds are rapidly mixed uniformly and heated to reaction temperature, and polymerization is initiated by the catalyst. Due to the mixing process generated by the screw stirring, the materials can be quickly mixed and completely reacted in the radial distribution, and the distribution and the mixing cannot be influenced by the axial pushing. That is, the materials at the adjacent positions are almost not back-mixed and not mutually influenced. Various byproducts generated by the polymerization reaction in the process, including part of low-boiling residues, can also be desorbed from the liquid film interface generated in the distribution mixing process and discharged from the devolatilization chamber. The resultant polymerization initiation product which has not been terminated is continuously fed into the reactor 2 to be uniformly mixed with a terminator to terminate the polymerization reaction. In the termination process, the residual low-boiling-point substances are released from the interior of the polymer under the combined action of high temperature, low pressure, large mass transfer area, rapid interface renewal rate and the like, and are removed through a devolatilization chamber of the reactor 2, so that the organopolysiloxane product with different viscosities, accurate and controllable viscosity ranges and ultralow volatile contents is obtained.
The following examples are intended to be illustrative of the invention only and are not to be construed as limiting the invention.
Example 1
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin-screw extruder body; a feed inlet is arranged at the barrel at the head of the screw rod of the body, and a discharge outlet is arranged at the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 240mm, and the length-diameter ratio of the screw is 28.
The twin-screw extruder 2 includes:
a twin screw extruder body; a feed inlet is arranged at the barrel body at the tail part of the screw, and a discharge outlet is arranged at the barrel body at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 55mm, and the length-diameter ratio of the screw is 38.
The polymerization-terminating method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding materials comprising linear siloxane, a catalyst and an end-capping reagent into a double-screw extruder 1 through a feeding hole of the reactor 1 in a continuous conveying mode, mixing and heating the feeding materials, and then starting polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the linear siloxane has the formula HO- [ SiMe 2 -O-] n H, wherein n is 1-500, and the feeding amount is 150kg/H; the catalyst is a phosphonitrile trimethylsiloxy alkyl catalyst (the effective mass concentration is 0.1 wt.%), and the feeding amount is 0.75kg/h; the capping agent has the formula Vi (SiMe) 2 O) n SiMe 2 Vi, wherein n is 1 to 20, me represents a methyl group, and Vi represents a vinyl group. The feeding amount is 10kg/h, the average temperature of a screw barrel of the double-screw extruder 1 is 120 ℃, the rotating speed of the screw is 100rpm, and the vacuum degree is 500-2,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of the twin-screw extruder 1 and directly conveying the product into the twin-screw extruder 2 in a continuous conveying manner, and simultaneously continuously conveying a terminator into the twin-screw extruder 2 at a rate of 0.75kg/h to terminate the polymerization reaction, wherein the terminator is Vi (SiMe) with the viscosity of 350cp 2 O) n SiMe 2 Solution of tri-n-propylamine in Vi (0.2 wt.% concentration). The materials are deeply devolatilized while the polymerization reaction is terminated in a double-screw extruder 2, the average temperature of a screw barrel is 160 ℃, the rotating speed of the screw is 100rpm, the vacuum degree is 200-1,000Pa, and finally the organopolysiloxane product with ultralow volatile content is obtained.
Example 2
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin screw extruder body; a feed inlet is arranged at the barrel at the head of the screw rod of the body, and a discharge outlet is arranged at the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 300mm, and the length-diameter ratio of the screw is 16.
The twin-screw extruder 2 includes:
a twin screw extruder body; a feed inlet is arranged at the barrel at the tail part of the screw, and a discharge outlet is arranged at the barrel at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 35mm, and the length-diameter ratio of the screw is 68.
The polymerization-terminating method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding materials comprising a siloxane ring mixture, a catalyst and an end capping agent into a double-screw extruder 1 through a feeding hole of the reactor 1 in a continuous conveying mode, mixing and heating the feeding materials, and then starting a polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the siloxane ring body is of the chemical formula [ SiMe 2 O] n And [ SiMeViO ]] n Wherein n is 3 to 50 and the feeding amount is 200kg/h; the catalyst is potassium silanol (the mass concentration is 15 wt.%), and the feeding amount is 0.015kg/h; the capping agent has the formula Vi (SiMe) 2 O) n SiMe 2 Vi, wherein n is 1-20, the feeding amount is 5.20kg/h, the average temperature of a screw barrel of the double-screw extruder 1 is 160 ℃, the rotating speed of the screw is 150rpm, and the vacuum degree is 10,000-50,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of a double-screw extruder 1, directly conveying the initial product into the double-screw extruder 2 in a continuous conveying mode, continuously conveying a terminator, namely silicon phosphate alkoxide, into the double-screw extruder 2 at a speed of 0.025kg/h (mass concentration of 9 wt.%) to terminate the polymerization reaction, deeply devolatilizing the materials while terminating the polymerization reaction in the double-screw extruder 2, wherein the average temperature of a screw cylinder is 180 ℃, the rotating speed of the screw is 100rpm, and the vacuum degree is 100-300Pa, and finally obtaining the organopolysiloxane product with ultralow volatile content.
Example 3
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin-screw extruder body; a feed inlet is arranged at the barrel at the head of the screw rod of the body, and a discharge outlet is arranged at the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 240mm, and the length-diameter ratio of the screw is 28.
The twin-screw extruder 2 includes:
a twin screw extruder body; a feed inlet is arranged at the barrel at the tail part of the screw, and a discharge outlet is arranged at the barrel at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 35mm, and the length-diameter ratio of the screw is 68.
The polymerization-terminating method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding materials comprising linear siloxane, a catalyst and an end-capping reagent into a double-screw extruder 1 through a feeding hole of the reactor 1 in a continuous conveying mode, mixing and heating the feeding materials, and then starting polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the linear siloxane has the formula HO- [ SiMe 2 -O-] n H, wherein n is 1-500, and the feeding amount is 100kg/H; the catalyst is ethyl acetate solution of phosphazene (mass concentration is 0.2 wt.%), and the feeding amount is 0.50kg/h; the capping agent has the formula Vi (SiMe) 2 O) n SiMe 2 Vi, wherein n is 1-20, the feeding amount is 3.40kg/h, the average temperature of a screw barrel of the double-screw extruder 1 is 130 ℃, the rotating speed of the screw is 100rpm, and the vacuum degree is 500-1,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of a double-screw extruder 1, directly conveying the product into the double-screw extruder 2 in a continuous conveying mode, continuously conveying an ethyl acetate solution of a terminator, namely trinonyl amine, into the double-screw extruder 2 at a speed of 1.00kg/h (mass concentration of 0.2 wt.%) to terminate the polymerization reaction, deeply devolatilizing the material while terminating the polymerization reaction in the double-screw extruder 2, wherein the average temperature of a screw cylinder body is 170 ℃, the rotating speed of the screw is 130rpm, and the vacuum degree is 200-500Pa, and finally obtaining the organopolysiloxane product with ultralow volatile content.
Example 4
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin-screw extruder body; a feed inlet is arranged at the barrel at the head of the screw rod of the body, and a discharge outlet is arranged at the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 240mm, and the length-diameter ratio of the screw is 28.
The twin-screw extruder 2 includes:
a twin-screw extruder body; a feed inlet is arranged at the barrel body at the tail part of the screw, and a discharge outlet is arranged at the barrel body at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 75mm, and the length-diameter ratio of the screw is 52.
The polymerization-terminating method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding materials comprising linear siloxane, a catalyst and an end-capping reagent into a double-screw extruder 1 through a feeding hole of the reactor 1 in a continuous conveying mode, mixing and heating the feeding materials, and then starting polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the linear siloxane has the formula HO- [ SiMe 2 -O-] n H, wherein n is 1-500, and the feeding amount is 150kg/H; the catalyst is a phosphazene toluene solution (with a mass concentration of 0.08 wt.%), and the feeding amount is 0.56kg/h; the capping agent has the formula Me (SiMe) 2 O) n SiMe 3 Wherein n is 1 to 20, the feeding amount is 2.35kg/h, the average temperature of a screw barrel of the double-screw extruder 1 is 100 ℃, the rotating speed of the screw is 80rpm, and the vacuum degree is 1000 to 5,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of a double-screw extruder 1, directly conveying the initial product into the double-screw extruder 2 in a continuous conveying mode, continuously conveying a toluene solution of a terminator silazane into the double-screw extruder 2 at a speed of 0.45kg/h (mass concentration of 0.2 wt.%) to terminate the polymerization reaction, deeply devolatilizing the materials while terminating the polymerization reaction in the double-screw extruder 2, wherein the average temperature of a screw cylinder body is 170 ℃, the rotating speed of the screw is 150rpm, and the vacuum degree is 200-500Pa, and finally obtaining the organopolysiloxane product with ultra-low volatile components.
Example 5
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin screw extruder body; a feed inlet is formed in the barrel at the head of the screw rod of the body, and a discharge outlet is formed in the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 300mm, and the length-diameter ratio of the screw is 16.
The twin-screw extruder 2 includes:
a twin screw extruder body; a feed inlet is arranged at the barrel at the tail part of the screw, and a discharge outlet is arranged at the barrel at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 35mm, and the length-diameter ratio of the screw is 68.
The polymerization-terminating method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding materials comprising siloxane rings, a catalyst and an end capping agent into a double-screw extruder 1 through a feeding hole of the reactor 1 in a continuous conveying mode, mixing and heating the feeding materials, and then starting polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the siloxane ring body has the chemical formula [ SiMe 2 O] n Wherein n is 3-50, and the feeding amount is 150kg/h; the catalyst is silicon alkoxide of tetramethylammonium hydroxide (the mass concentration is 10 wt.%), and the feeding amount is 0.015kg/h; the capping agent has the formula Vi (SiMe) 2 O) n SiMe 2 Vi, where n is from 1 to 20 and the feed rate is 2.71kg/h, of a twin-screw extruder 1The average temperature of the barrel of the screw is 120 ℃, the rotation speed of the screw is 120rpm, and the vacuum degree is 10,000-50,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of the double-screw extruder 1, directly conveying the polymerized initial product into the double-screw extruder 2 in a continuous conveying mode, simultaneously carrying out deep devolatilization while carrying out polymerization termination reaction on the material in the double-screw extruder 2 due to the fact that the temperature of the material in the double-screw extruder 2 is increased, wherein the average temperature of a screw cylinder body is 160 ℃, the rotating speed of the screw is 50rpm, and the vacuum degree is 100-300Pa, and finally obtaining the organic polysiloxane product with ultralow volatile component.
Example 6
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
the twin-screw extruder 1 includes:
a twin-screw extruder body; a feed inlet is formed in the barrel at the head of the screw rod of the body, and a discharge outlet is formed in the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 240mm, and the length-diameter ratio of the screw is 28.
The twin-screw extruder 2 includes:
a twin screw extruder body; a feed inlet is arranged at the barrel at the tail part of the screw, and a discharge outlet is arranged at the barrel at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 75mm, and the length-diameter ratio of the screw is 52.
The polymerization-terminating method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding materials comprising linear siloxane and a catalyst into a double-screw extruder 1 through a feeding hole of the reactor 1 in a continuous conveying mode, mixing and heating the materials, and then starting polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the linear siloxane has the formula HO- [ SiMe 2 -O-] n H, wherein n is 1-500, and the feeding amount is 150kg/H; the catalyst is ethyl acetate solution of phosphazene (mass concentration is 0.1 wt.%), and the feeding amount is 0.45kg/h; the average temperature of the screw barrel of the double-screw extruder 1 is 80 ℃, the screw rotating speed is 120rpm, and the vacuum degree is 3000-10,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of a double-screw extruder 1, directly conveying the product into the double-screw extruder 2 in a continuous conveying mode, continuously conveying an ethyl acetate solution of a terminator tri-n-butylamine into the double-screw extruder 2 at a speed of 0.90kg/h (mass concentration of 0.1 wt.%) to terminate the polymerization reaction, deeply devolatilizing the material in the double-screw extruder 2 while terminating the polymerization reaction, wherein the average temperature of a screw cylinder body is 170 ℃, the rotating speed of the screw is 150rpm, and the vacuum degree is 300-1,000Pa, and finally obtaining the organopolysiloxane product with ultralow volatile content.
Example 7
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin screw extruder body; a feed inlet is arranged at the barrel at the head of the screw rod of the body, and a discharge outlet is arranged at the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 300mm, and the length-diameter ratio of the screw is 16.
The twin-screw extruder 2 includes:
a twin screw extruder body; a feed inlet is arranged at the barrel at the tail part of the screw, and a discharge outlet is arranged at the barrel at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 35mm, and the length-diameter ratio of the screw is 68.
The polymerization-terminating method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding a mixture comprising siloxane rings and linear siloxane, a catalyst and an end-capping agent into a double-screw extruder 1 through a feeding port of the reactor 1 in a continuous conveying manner, mixing and heating the feeding materials, and then starting a polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the linear siloxane has the formula HO- [ SiMe 2 -O-] n H, wherein n is 1 to 500, and the chemical formula of the siloxane ring body is [ SiMe 2 O] n Wherein n is 3-50, the two are mixed according to a certain proportion, and the feeding amount is 200kg/h; the catalyst is alkali gel of potassium silanol (the effective mass concentration is 5 wt.%), and the feeding amount is 0.04kg/h; the capping agent has the formula Vi (SiMe) 2 O) n SiMe 2 Vi, wherein n is 1-20, the feeding amount is 2.40kg/h, the average temperature of a screw barrel of the double-screw extruder 1 is 160 ℃, the rotating speed of the screw is 150rpm, and the vacuum degree is 10,000-50,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of a double-screw extruder 1, directly conveying the product into the double-screw extruder 2 in a continuous conveying mode, continuously conveying a terminator caprylic silanol hydrochloric acid gum into the double-screw extruder 2 at a speed of 0.04kg/h (mass concentration of 5 wt.%) to terminate the polymerization reaction, deeply devolatilizing the material while terminating the polymerization reaction in the double-screw extruder 2, wherein the average temperature of a screw barrel is 180 ℃, the rotating speed of the screw is 50rpm, and the vacuum degree is 100-300Pa, and finally obtaining the organic polysiloxane product with ultra-low volatile components.
Example 8
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin-screw extruder body; a feed inlet is arranged at the barrel at the head of the screw rod of the body, and a discharge outlet is arranged at the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 240mm, and the length-diameter ratio of the screw is 28.
The twin-screw extruder 2 includes:
a twin screw extruder body; a feed inlet is arranged at the barrel at the tail part of the screw, and a discharge outlet is arranged at the barrel at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 75mm, and the length-diameter ratio of the screw is 52.
The polymerization-termination method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding materials comprising linear siloxane and a catalyst into a double-screw extruder 1 through a feeding hole of the reactor 1 in a continuous conveying mode, mixing and heating the materials, and then starting polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the linear siloxane has the formula HO- [ SiMe 2 -O-] n H, wherein n is 1-500, and the feeding amount is 150kg/H; the catalyst is a tetrachloroethane solution of phosphazene (with the mass concentration of 0.1 wt.%), and the feeding amount is 0.45kg/h; the average temperature of the screw barrel of the double-screw extruder 1 is 90 ℃,the rotation speed of the screw is 90rpm, and the vacuum degree is 3000-10,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of a double-screw extruder 1, directly conveying the initial product into the double-screw extruder 2 in a continuous conveying mode, continuously conveying a tetrachloroethane solution of a terminator silazane into the double-screw extruder 2 at a speed of 0.90kg/h (mass concentration of 0.1 wt.%) to terminate the polymerization reaction, deeply devolatilizing the materials while performing the termination polymerization reaction in the double-screw extruder 2, wherein the average temperature of a screw barrel is 170 ℃, the rotating speed of the screw is 100rpm, and the vacuum degree is 300-1,000Pa, and finally obtaining the organopolysiloxane product with ultralow volatile content.
Example 9
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin screw extruder body; a feed inlet is arranged at the barrel at the head of the screw rod of the body, and a discharge outlet is arranged at the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 300mm, and the length-diameter ratio of the screw is 16.
The twin-screw extruder 2 includes:
a twin-screw extruder body; a feed inlet is arranged at the barrel at the tail part of the screw, and a discharge outlet is arranged at the barrel at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 35mm, and the length-diameter ratio of the screw is 68.
The polymerization-termination method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding materials comprising siloxane ring bodies, a catalyst and an end-capping agent into a double-screw extruder 1 through a feeding hole of the reactor 1 in a continuous conveying mode, mixing and heating the materials, and then starting polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the siloxane ring body is of the chemical formula [ SiMe 2 O] n Wherein n is 3-50, and the feeding amount is 200kg/h; the catalyst is silanol potassium alkali glue (with the mass concentration of 5 wt.%), and the feeding amount is 0.04kg/h; the capping agent has the formula Vi (SiMe) 2 O) n SiMe 2 Vi, wherein n is 1-50, the feeding amount is 3.40kg/h, the average temperature of a screw barrel of the double-screw extruder 1 is 160 ℃, the rotating speed of the screw is 150rpm, and the vacuum degree is 10,000-50,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of a double-screw extruder 1, directly conveying the product into a double-screw extruder 2 in a continuous conveying mode, continuously conveying a terminator, namely silicon phosphate alkoxide, into the double-screw extruder 2 at a speed of 0.04kg/h (mass concentration of 5 wt.%) to terminate the polymerization reaction, deeply devolatilizing the material while terminating the polymerization reaction in the double-screw extruder 2, wherein the average temperature of a screw barrel is 180 ℃, the rotating speed of the screw is 100rpm, and the vacuum degree is 100-300Pa, and finally obtaining the organic polysiloxane product with ultralow volatile content.
Example 10
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin screw extruder body; a feed inlet is arranged at the barrel at the head of the screw rod of the body, and a discharge outlet is arranged at the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 300mm, and the length-diameter ratio of the screw is 16.
The twin-screw extruder 2 includes:
a twin screw extruder body; a feed inlet is arranged at the barrel at the tail part of the screw, and a discharge outlet is arranged at the barrel at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 35mm, and the length-diameter ratio of the screw is 68.
The polymerization-terminating method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding materials comprising siloxane rings, a catalyst and an end capping agent into a double-screw extruder 1 through a feeding hole of the reactor 1 in a continuous conveying mode, mixing and heating the feeding materials, and then starting polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the siloxane ring body has the chemical formula [ SiMe 2 O] n Wherein n is 3-50, and the feeding amount is 150kg/h; the catalyst is silicon alkoxide of cesium hydroxide (mass concentration is 5 wt.%), and the feeding amount is 0.03kg/h; the capping agent has the formula Me (SiMe) 2 O) n SiMe 3 Wherein n is 1-80, the feeding amount is 3.53kg/h, the average temperature of a screw barrel of the double-screw extruder 1 is 120 ℃, the rotating speed of the screw is 120rpm, and the vacuum degree is 10,000-50,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of a double-screw extruder 1, directly conveying the product into the double-screw extruder 2 in a continuous conveying mode, continuously conveying a terminator of a silanol-acetic acid hydrochloride gel into the double-screw extruder 2 at a speed of 0.03kg/h (mass concentration of 5 wt.%) to terminate the polymerization reaction, deeply devolatilizing the material while terminating the polymerization reaction in the double-screw extruder 2, wherein the average temperature of a screw barrel is 180 ℃, the rotating speed of the screw is 90rpm, and the vacuum degree is 100-300Pa, and finally obtaining the organic polysiloxane product with ultra-low volatile components.
Example 11
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin screw extruder body; a feed inlet is arranged at the barrel at the head of the screw rod of the body, and a discharge outlet is arranged at the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 300mm, and the length-diameter ratio of the screw is 16.
The twin-screw extruder 2 includes:
a twin screw extruder body; a feed inlet is arranged at the barrel at the tail part of the screw, and a discharge outlet is arranged at the barrel at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 35mm, and the length-diameter ratio of the screw is 68.
The polymerization-terminating method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding a mixture comprising siloxane rings and linear siloxane, a catalyst and an end-capping agent into a double-screw extruder 1 through a feeding port of the reactor 1 in a continuous conveying manner, mixing and heating the feeding materials, and then starting a polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the linear siloxane has the formula HO- [ SiMe 2 -O-] n H, wherein n is 1 to 500, and the chemical formula of the siloxane ring body is [ SiMe 2 O] n Wherein n is 3-50, the two are mixed according to a certain proportion, and the feeding amount is 200kg/h; the catalyst is a normal hexane solution of phosphazene(the effective mass concentration is 5 wt.%), and the feeding amount is 0.04kg/h; the capping agent has the formula Me (SiMe) 2 O) n SiMe 3 Wherein n is 1-80, the feeding amount is 2.30kg/h, the average temperature of a screw barrel of the double-screw extruder 1 is 160 ℃, the rotating speed of the screw is 150rpm, and the vacuum degree is 10,000-50,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of a double-screw extruder 1, directly conveying the product into the double-screw extruder 2 in a continuous conveying manner, continuously conveying a terminator of phospho-silanol-HCl glue into the double-screw extruder 2 at a speed of 0.03kg/h (mass concentration of 6 wt.%) to terminate the polymerization reaction, deeply devolatilizing the material while terminating the polymerization reaction in the double-screw extruder 2, wherein the average temperature of a screw cylinder is 180 ℃, the rotating speed of the screw is 50rpm, and the vacuum degree is 100-300Pa, and finally obtaining the ultra-low volatile organopolysiloxane product.
Example 12
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin screw extruder body; a feed inlet is arranged at the barrel at the head of the screw rod of the body, and a discharge outlet is arranged at the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 240mm, and the length-diameter ratio of the screw is 28.
The twin-screw extruder 2 includes:
a twin screw extruder body; a feed inlet is arranged at the barrel at the tail part of the screw, and a discharge outlet is arranged at the barrel at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 75mm, and the length-diameter ratio of the screw is 52.
The polymerization-termination method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding materials comprising linear siloxane and a catalyst into a double-screw extruder 1 through a feeding hole of the reactor 1 in a continuous conveying mode, mixing and heating the materials, and then starting polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the linear siloxane has the formula HO- [ SiMe 2 -O-] n H, wherein n is 1-500, and the feeding amount is 150kg/H; the catalyst is ethyl acetate solution of phosphazene (mass concentration is 0.1 wt.%), and the feeding amount is 0.45kg/h; the average temperature of the screw barrel of the double-screw extruder 1 is 100 ℃, the screw rotating speed is 70rpm, and the vacuum degree is 3000-10,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of a double-screw extruder 1, directly conveying the product into the double-screw extruder 2 in a continuous conveying mode, continuously conveying an ethyl acetate solution of a terminator, namely trinonyl amine, into the double-screw extruder 2 at a speed of 0.90kg/h (mass concentration of 0.1 wt.%) to terminate the polymerization reaction, deeply devolatilizing the material while terminating the polymerization reaction in the double-screw extruder 2, wherein the average temperature of a screw cylinder body is 170 ℃, the rotating speed of the screw is 80rpm, and the vacuum degree is 300-1,000Pa, and finally obtaining the organopolysiloxane product with ultralow volatile content.
Example 13
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin-screw extruder body; a feed inlet is arranged at the barrel at the head of the screw rod of the body, and a discharge outlet is arranged at the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 300mm, and the length-diameter ratio of the screw is 16.
The twin-screw extruder 2 includes:
a twin screw extruder body; a feed inlet is arranged at the barrel at the tail part of the screw, and a discharge outlet is arranged at the barrel at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The screw diameter of the twin-screw extruder body is 35mm, and the length-diameter ratio of the screw is 68.
The polymerization-termination method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding materials comprising siloxane rings, a catalyst and an end capping agent into a double-screw extruder 1 through a feeding hole of the reactor 1 in a continuous conveying mode, mixing and heating the feeding materials, and then starting polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the siloxane ring body is of the chemical formula [ SiMe 2 O] n Wherein n is 3-50, and the feeding amount is 180kg/h; the catalyst is silanol salt-alkali glue of tetramethylammonium hydroxide (the mass concentration is 5 wt.%), and the feeding amount is 0.05kg/h; the capping agent has the formula Vi (SiMe) 2 O) n SiMe 2 Vi, wherein n is 1-80, the feeding amount is 2.25kg/h, the average temperature of a screw barrel of the double-screw extruder 1 is 120 ℃, the rotating speed of the screw is 150rpm, and the vacuum degree is 10,000-50,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of the double-screw extruder 1, directly conveying the polymerized initial product into the double-screw extruder 2 in a continuous conveying mode, simultaneously carrying out deep devolatilization while carrying out polymerization reaction termination on the material in the double-screw extruder 2 due to the temperature rise of the material in the double-screw extruder 2, wherein the average temperature of a screw cylinder body is 160 ℃, the rotating speed of the screw is 120rpm, and the vacuum degree is 100-300Pa, and finally obtaining the organic polysiloxane product with ultralow volatile component.
Example 14
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin screw extruder body; a feed inlet is arranged at the barrel at the head of the screw rod of the body, and a discharge outlet is arranged at the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 240mm, and the length-diameter ratio of the screw is 28.
The twin-screw extruder 2 includes:
a twin screw extruder body; a feed inlet is arranged at the barrel at the tail part of the screw, and a discharge outlet is arranged at the barrel at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 75mm, and the length-diameter ratio of the screw is 52.
The polymerization-terminating method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding materials comprising linear siloxane, a catalyst and an end-capping reagent into a double-screw extruder 1 through a feeding hole of the reactor 1 in a continuous conveying mode, mixing and heating the feeding materials, and then starting polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the linear siloxane has the formula HO- [ SiMe 2 -O-] n H, wherein n is 1-500, and the feeding amount is 150kg/H; the catalyst is a phosphazene toluene solution (mass concentration is 0.1 wt.%), and the feed isThe amount is 0.75kg/h; the capping agent has the formula Me (SiMe) 2 O) n SiMe 3 Wherein n is 1-100, the feeding amount is 3.10kg/h, the average temperature of a screw barrel of the double-screw extruder 1 is 120 ℃, the rotating speed of the screw is 60rpm, and the vacuum degree is 500-2,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of a double-screw extruder 1, directly conveying the polymerized initial product into the double-screw extruder 2 in a continuous conveying mode, simultaneously continuously conveying a toluene solution of a terminator silazane into the double-screw extruder 2 at a speed of 0.75kg/h (mass concentration of 0.1 wt.%) to terminate the polymerization reaction, deeply devolatilizing the materials while terminating the polymerization reaction in the double-screw extruder 2, wherein the average temperature of a screw barrel is 180 ℃, the rotating speed of a screw is 120rpm, and the vacuum degree is 200-500Pa, and finally obtaining the organopolysiloxane product with ultra-low volatile components.
Example 15
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin-screw extruder body; a feed inlet is arranged at the barrel at the head of the screw rod of the body, and a discharge outlet is arranged at the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The screw diameter of the twin-screw extruder body is 240mm, and the length-diameter ratio of the screw is 28.
The twin-screw extruder 2 includes:
a twin screw extruder body; a feed inlet is arranged at the barrel body at the tail part of the screw, and a discharge outlet is arranged at the barrel body at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The screw diameter of the twin-screw extruder body is 35mm, and the length-diameter ratio of the screw is 68.
The polymerization-terminating method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding materials comprising a linear siloxane mixture, a catalyst and an end-capping agent into a double-screw extruder 1 through a feeding hole of the reactor 1 in a continuous conveying mode, mixing and heating the materials, and then starting a polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the linear siloxane is of the formula HO- [ SiMe ] 2 -O-] m H and HO- [ SiMe 2 -O-] n -[SiMeVi-O] p H, wherein m, n and p are 10-100, and the feeding amount is 160kg/H; the catalyst is a methylene dichloride solution of phosphazene (with the mass concentration of 0.2 wt.%), and the feeding amount is 0.80kg/h; the capping agent has the formula Vi (SiMe) 2 O) n SiMe 2 Vi, wherein n is 1-80, the feeding amount is 4.30kg/h, the average temperature of a screw barrel of the double-screw extruder 1 is 130 ℃, the rotating speed of the screw is 120rpm, and the vacuum degree is 300-1,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of a double-screw extruder 1, directly conveying the initial product into the double-screw extruder 2 in a continuous conveying mode, continuously conveying an ethyl acetate solution of a terminator tripropylamine into the double-screw extruder 2 at a speed of 0.40kg/h (mass concentration of 0.8 wt.%) to terminate polymerization reaction, deeply devolatilizing the materials in the double-screw extruder 2 while terminating polymerization reaction, wherein the average temperature of a screw cylinder is 170 ℃, the rotating speed of the screw is 100rpm, and the vacuum degree is 200-500Pa, and finally obtaining the organopolysiloxane product with ultra-low volatile components.
Example 16
This example provides a polymerization-termination apparatus for the continuous production of organopolysiloxanes as shown in FIG. 1, comprising:
a twin-screw extruder 1 for efficiently carrying out siloxane polymerization;
a twin-screw extruder 2 directly connected to the discharge port of the twin-screw extruder 1 for efficiently terminating the polymerization reaction;
wherein the twin-screw extruder 1 comprises:
a twin screw extruder body; a feed inlet is formed in the barrel at the head of the screw rod of the body, and a discharge outlet is formed in the barrel at the tail of the screw rod;
a devolatilization chamber arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 240mm, and the length-diameter ratio of the screw is 28.
The twin-screw extruder 2 includes:
a twin screw extruder body; a feed inlet is arranged at the barrel at the tail part of the screw, and a discharge outlet is arranged at the barrel at the head part of the screw;
and the devolatilization chamber is arranged on the cylinder body of the double-screw extruder body.
The diameter of the screw of the double-screw extruder body is 75mm, and the length-diameter ratio of the screw is 52.
The polymerization-terminating method for continuously producing polysiloxane using the above apparatus comprises:
1) Feeding materials comprising linear siloxane and a catalyst into a double-screw extruder 1 through a feeding hole of the reactor 1 in a continuous feeding mode, mixing and heating the materials, and then starting polymerization reaction and devolatilization at the same time to obtain a polymerized initial product;
the linear siloxane has the formula HO- [ SiMe 2 -O-] n H, wherein n is 1-500, and the feeding amount is 150kg/H; the catalyst is ethyl acetate solution of phosphazene (with mass concentration of 0.1 wt.%), and the feeding amount is 0.45kg/h; the average temperature of a screw barrel of the double-screw extruder 1 is 110 ℃, the rotating speed of the screw is 50rpm, and the vacuum degree is 3000-10,000Pa.
2) Discharging the polymerized initial product obtained in the step 1) from a discharge port of a double-screw extruder 1, directly conveying the product into the double-screw extruder 2 in a continuous conveying mode, continuously conveying an ethyl acetate solution of a terminator, namely trinonyl amine, into the double-screw extruder 2 at a speed of 0.90kg/h (mass concentration of 0.1 wt.%) to terminate the polymerization reaction, deeply devolatilizing the material while terminating the polymerization reaction in the double-screw extruder 2, wherein the average temperature of a screw cylinder body is 170 ℃, the rotating speed of the screw is 60rpm, the vacuum degree is 300-1,000Pa, and finally obtaining the organopolysiloxane product with ultralow volatile content.
Example 17
The physical and chemical properties of the various organopolysiloxanes of different viscosities prepared in examples 1-16 were tested, and the results are shown in Table 1:
TABLE 1 Properties of the organopolysiloxanes prepared in examples 1 to 16
a. The temperature at which 5wt.% mass loss of the polysiloxane occurs is defined as its thermal decomposition temperature, experimental conditions: the heating rate was 10 ℃/min in a nitrogen atmosphere.
As can be seen from the above table, the organopolysiloxane product prepared by the apparatus and method of the present invention has a wide viscosity range, low volatile content, uniform molecular weight distribution, low inorganic salt content, good transparency, and high thermal stability.
In which examples 6, 8, 12, 16 prepared are α, ω -dihydroxypolydimethylsiloxanes having different viscosities. Linear siloxane, i.e. low-viscosity alpha, omega-dihydroxy polydimethylsiloxane, is used as a starting material and is prepared by polycondensation without addition of an end-capping agent. Generally, the reaction rate is high, the viscosity/molecular weight of the product is difficult to control in real time in the traditional and the prior art, and even after the terminator is added, the viscosity of the product is still increased because the two are difficult to mix uniformly. It is highly dependent on the manufacturer's experience to add the terminating agent in advance before the material reaches the desired viscosity/molecular weight to make it possible to obtain the desired product.
In this patent, the twin-screw reactor 2 is used for the termination of the polymerization with high efficiency, and the residence time is usually controlled within 2min, most of the time being about 30 s. Therefore, compared with the traditional process and a static mixer termination process, the continuous dynamic mixing-termination process has the advantages of high termination efficiency, small addition amount of the required termination agent and the like, and is easier to realize real-time control on the viscosity/molecular weight of the product. In the above examples, samples were taken from the tail of the twin-screw extruder 1 (after quenching the reaction rapidly) and from the discharge port of the twin-screw extruder 2, respectively, and it was found that there was almost no significant difference in the molecular weight distribution and the viscosity.
The comparison of the viscosities of samples before and after termination of the reactions in examples 6, 8, 12 and 16 and the respective reaction parameters are shown in Table 2:
TABLE 2 comparison of examples 6, 8, 12, 16 before and after termination of the reaction
It can be seen from table 2 that, thanks to the efficient and rapid termination of the reaction, there is no significant difference in properties such as viscosity and molecular weight distribution when the product is pushed to the end of the reactor 1 compared to the final product at the outlet from the end of the reactor 2. The above results show that the apparatus and method of the present invention can achieve real-time control of viscosity/molecular weight of organopolysiloxanes such as alpha, omega-dihydroxypolydimethylsiloxane.
While the invention has been described with reference to one or more embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Moreover, all numbers recited herein are to be interpreted as if both exact and approximate values were explicitly recited.
Claims (22)
1. A polymerization-termination apparatus for the continuous production of organopolysiloxanes comprising:
a reactor 1 for carrying out a polymerization reaction of siloxane;
and the feeding hole of the reactor 2 is connected with the discharging hole of the reactor 1 and is used for terminating the polymerization reaction.
2. The apparatus of claim 1, wherein reactor 1 is devolatilized while conducting the polymerization reaction, and/or reactor 2 is devolatilized while conducting the termination polymerization reaction.
3. The device according to claim 1, wherein the organopolysiloxane produced has a viscosity in the range of 300-20,000,000mpa-S, preferably 1,000-10,000mpa-S, more preferably 100,000-1,000,000mpa-S, even more preferably 3,000,000-10,000,000mpa-S.
4. The device according to claim 1, wherein the organopolysiloxane produced has a low volatile content, preferably less than 0.5%, more preferably less than 0.3%.
5. The device according to claim 1, wherein the organopolysiloxane produced has a narrow molecular weight distribution, preferably 1.4-2.3, more preferably 1.5-2.0.
6. The device according to claim 1, wherein the organopolysiloxane produced has a low content of inorganic salts, preferably <11ppm, more preferably <0.1ppm.
7. The apparatus according to claim 1, wherein the produced organopolysiloxane has high thermal stability, preferably a thermal decomposition temperature of 380 ℃ to 510 ℃, more preferably a thermal decomposition temperature of 385 ℃ to 470 ℃.
8. The apparatus according to claim 1, wherein the reactor 1 is a co-or counter-rotating twin-screw extruder 1, and the reactor 2 is a co-or counter-rotating twin-screw extruder 2.
9. The apparatus of claim 1, wherein the front end of the reactor 2 is provided with a terminator feeding port.
10. The apparatus according to claim 1, characterized in that the outlet of the reactor 1 is directly connected to the inlet of the reactor 2, preferably in a straight line or perpendicularly to each other or at some other angle.
11. The apparatus according to claim 8, wherein the screw diameter of the twin-screw extruder 1 is 36-360mm, preferably 120-240mm.
12. The apparatus according to claim 8, wherein the screw diameter of the twin-screw extruder 2 is 36-240mm, preferably 80-240mm.
13. The apparatus according to claim 8, wherein the screw speed of the twin-screw extruder 1 is 1-200rpm, preferably 1-150rpm, more preferably 50-120rpm.
14. The apparatus according to claim 8, wherein the screw speed of the twin-screw extruder 2 is 1-600rpm, preferably 1-150rpm, more preferably 60-150rpm.
15. The apparatus according to claim 1, wherein the temperature of the reactor 1 is 20-180 ℃, preferably 110-150 ℃, more preferably 80-110 ℃.
16. The apparatus according to claim 1, wherein the temperature of the reactor 2 is 20-180 ℃, preferably 100-170 ℃, more preferably 160-170 ℃.
17. The apparatus according to claim 1, wherein the pressure of the reactor 2 is 0-50kPa, preferably 0-5kPa.
18. A polymerization-termination process for the continuous production of organopolysiloxanes using the apparatus according to any of claims 1 to 17, comprising the steps of:
a) Adding siloxane including linear siloxane or cyclic siloxane or a mixture of the linear siloxane and the cyclic siloxane, an end-capping agent and a catalyst in sequence into a reactor 1 to perform polymerization while performing partial devolatilization to obtain a polymerized initial product;
b) The polymerized initial product is extruded from reactor 1 and fed to reactor 2 where it is thoroughly mixed with a terminating agent to effect termination of the polymerization reaction while undergoing deep devolatilization to give the organopolysiloxane.
19. The method according to claim 18, wherein the linear or cyclic siloxane in step a) has the following repeating structural unit- [ SiR ™ 1 R 2 -O-] n Wherein n is 1 to 500, preferably 2 to 100, more preferably 3 to 20 1 、R 2 Is H or optionally substituted alkyl, alkenyl, aryl, alkaryl or aralkyl.
20. The method of claim 18, wherein the endcapping agent is selected from the group consisting of divinyltetramethyldisiloxane, hexamethyldisiloxane represented by the general formula R 3 -[SiMe 2 -O-] n SiMe 2 R 3 Linear polymers and mixtures thereof of formula (I) wherein n is 1 to 20 3 Is H, OH or an optionally substituted alkyl, alkenyl, aryl, alkaryl, or aralkyl group.
21. The method of claim 18, wherein the catalyst is selected from one or more of potassium hydroxide, sodium hydroxide, cesium hydroxide, lithium hydroxide, tetramethylammonium hydroxide, phosphazenes, or silicon alkoxides of the foregoing.
22. The method of claim 18, the terminating agent being selected from one or more of the following: phosphoric acid, acetic acid, octanoic acid, of the formula R 4 3 N tertiary amine of the formula R 4 2 Secondary amine of NH of the formula R 4 NH 2 Wherein R is 4 Alkyl groups having 2 to 10 carbon atoms, silazanes, or silicon alkoxides of the foregoing.
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| PCT/CN2023/116914 WO2024051671A1 (en) | 2022-09-06 | 2023-09-05 | Polymerization-termination device and method for continuous production of organopolysiloxanes |
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| WO2024051671A1 (en) * | 2022-09-06 | 2024-03-14 | 江西蓝星星火有机硅有限公司 | Polymerization-termination device and method for continuous production of organopolysiloxanes |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4551515A (en) * | 1984-02-27 | 1985-11-05 | General Electric Company | Process for the continuous manufacture of silicone gums |
| CN1259534A (en) * | 1998-08-26 | 2000-07-12 | 陶氏康宁公司 | Continuous process for producing organosilicon polymer |
| CN1259535A (en) * | 1998-08-26 | 2000-07-12 | 陶氏康宁公司 | Continuous process for producing organosilicon polymer |
| CN102134321A (en) * | 2011-03-02 | 2011-07-27 | 浙江环新氟材料股份有限公司 | Method for preparing fluorosilicone rubbers by using screw extruder |
| CN111574714A (en) * | 2020-05-15 | 2020-08-25 | 浙江新安化工集团股份有限公司 | Continuous production system and production method of polysiloxane |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1110696A3 (en) * | 1999-12-21 | 2001-11-21 | General Electric Company | Continuous process to prepare silicone compositions |
| US6391234B1 (en) * | 1999-12-21 | 2002-05-21 | General Electric Company | Compounding filled silicone compositions |
| CN113896892A (en) * | 2021-09-22 | 2022-01-07 | 杭州四马化工科技有限公司 | Method for continuously producing polysiloxane |
| CN115417991B (en) * | 2022-09-06 | 2024-02-09 | 江西蓝星星火有机硅有限公司 | Polymerization-termination device and method for continuous production of organopolysiloxane |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4551515A (en) * | 1984-02-27 | 1985-11-05 | General Electric Company | Process for the continuous manufacture of silicone gums |
| CN1259534A (en) * | 1998-08-26 | 2000-07-12 | 陶氏康宁公司 | Continuous process for producing organosilicon polymer |
| CN1259535A (en) * | 1998-08-26 | 2000-07-12 | 陶氏康宁公司 | Continuous process for producing organosilicon polymer |
| CN102134321A (en) * | 2011-03-02 | 2011-07-27 | 浙江环新氟材料股份有限公司 | Method for preparing fluorosilicone rubbers by using screw extruder |
| CN111574714A (en) * | 2020-05-15 | 2020-08-25 | 浙江新安化工集团股份有限公司 | Continuous production system and production method of polysiloxane |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024051671A1 (en) * | 2022-09-06 | 2024-03-14 | 江西蓝星星火有机硅有限公司 | Polymerization-termination device and method for continuous production of organopolysiloxanes |
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