WO2019119466A1 - 一种聚碳酸酯多元醇及其合成方法和应用 - Google Patents

一种聚碳酸酯多元醇及其合成方法和应用 Download PDF

Info

Publication number
WO2019119466A1
WO2019119466A1 PCT/CN2017/118254 CN2017118254W WO2019119466A1 WO 2019119466 A1 WO2019119466 A1 WO 2019119466A1 CN 2017118254 W CN2017118254 W CN 2017118254W WO 2019119466 A1 WO2019119466 A1 WO 2019119466A1
Authority
WO
WIPO (PCT)
Prior art keywords
carbonate
fraction
reaction
feed
mass percentage
Prior art date
Application number
PCT/CN2017/118254
Other languages
English (en)
French (fr)
Inventor
孙双翼
鞠昌迅
刘斌
赵晶
黎源
华卫琦
Original Assignee
万华化学集团股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 万华化学集团股份有限公司 filed Critical 万华化学集团股份有限公司
Priority to EP17935128.3A priority Critical patent/EP3730535A4/en
Publication of WO2019119466A1 publication Critical patent/WO2019119466A1/zh

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L75/00—Compositions of polyureas or polyurethanes; Compositions of derivatives of such polymers
    • C08L75/04—Polyurethanes
    • C08L75/06—Polyurethanes from polyesters
    • 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
    • C08G18/00—Polymeric products of isocyanates or isothiocyanates
    • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40—High-molecular-weight compounds
    • C08G18/42—Polycondensates having carboxylic or carbonic ester groups in the main chain
    • C08G18/44—Polycarbonates
    • 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
    • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/64—Polyesters containing both carboxylic ester groups and carbonate 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
    • C08G64/00—Macromolecular compounds obtained by reactions forming a carbonic ester link in the main chain of the macromolecule
    • C08G64/20—General preparatory processes
    • C08G64/30—General preparatory processes using carbonates
    • 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
    • C08G64/00—Macromolecular compounds obtained by reactions forming a carbonic ester link in the main chain of the macromolecule
    • C08G64/20—General preparatory processes
    • C08G64/30—General preparatory processes using carbonates
    • C08G64/305—General preparatory processes using carbonates and alcohols
    • 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
    • C08G65/00—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule
    • C08G65/02—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from cyclic ethers by opening of the heterocyclic ring
    • C08G65/26—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from cyclic ethers by opening of the heterocyclic ring from cyclic ethers and other compounds
    • C08G65/2603—Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from cyclic ethers by opening of the heterocyclic ring from cyclic ethers and other compounds the other compounds containing oxygen
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
    • C09D175/04—Polyurethanes
    • C09D175/06—Polyurethanes from polyesters

Definitions

  • the invention relates to the technical field of preparation of polycarbonate polyols, in particular to a semi-continuous synthesis method for efficiently preparing polycarbonate polyols.
  • Polycarbonate polyols are one of the important raw materials for the production of polyurethanes. For example, as a soft chain end of a polyurethane elastomer, it has excellent resistance to hydrolysis, heat, oil, and aging. Polycarbonate polyols are usually transesterified by small molecular polyols or small alcohols and lactones, and small molecular carbonates under a catalyst to form polycarbonate polyols and small molecular by-products by removing small molecular byproducts. The reaction is pushed thoroughly and the product is obtained.
  • the most important polycarbonate polyol product is a homopolymerized or copolymerized polycarbonate diol based on 1,6-hexanediol (HDO).
  • the homopolymerized product uses only 1,6-hexanediol as a small molecule polyol, and the copolymerized product uses two or more kinds of raw materials at the same time, such as 1,6-hexanediol and 1,4-butanediol (BDO) (Japanese Patent No. 2885872) No.), or 1,6-hexanediol and 1,5-pentanediol (PDO) (Japanese Patent No. 1822688), or 1,6-hexanediol and caprolactone/valerolactone (CN01813544.7) ).
  • BDO 1,6-hexanediol and 1,4-butanediol
  • PDO 1,6-hexane
  • Dialkyl carbonates such as dimethyl carbonate (DMC), diethyl carbonate; diaryl carbonates such as diphenyl carbonate; alkylene carbonates such as ethylene carbonate and propylene carbonate.
  • DMC dimethyl carbonate
  • diaryl carbonates such as diphenyl carbonate
  • alkylene carbonates such as ethylene carbonate and propylene carbonate.
  • the small molecule carbonate undergoes a transesterification reaction with a small molecule alcohol in which a carbonyl group enters the product, and both groups are converted into by-products, which are removed from the reaction system. Taking dimethyl carbonate as an example, two molecules of methanol are removed.
  • the small molecular carbonate Since the small molecular carbonate has a low boiling point and is also significantly vaporized at the reaction temperature, it is necessary to rectify and separate the mixture of the small molecule carbonate and the by-products and other compounds. A mixture of carbonate and by-products is usually produced.
  • the by-product methanol is azeotroped with the starting material dimethyl carbonate, and the overhead product is an azeotrope.
  • the starting polyol and the product have a relatively high boiling point and can be easily separated and refluxed into the reaction vessel during rectification.
  • Polycarbonate polyol production requires the production of a specific molecular weight (e.g., 1000 or 2000), or a product commonly described in the industry to produce a specific hydroxyl value (e.g., 112 mg KOH/g or 56 mg KOH/g). Therefore, it is necessary to accurately measure the proportion of alcohol and carbonate to participate in the reaction.
  • a specific molecular weight e.g., 1000 or 2000
  • a product commonly described in the industry e.g., 112 mg KOH/g or 56 mg KOH/g. Therefore, it is necessary to accurately measure the proportion of alcohol and carbonate to participate in the reaction.
  • DMC dimethyl carbonate
  • one method is to pressurize the system (for example, CN200410079804.1) to facilitate Increase the reaction temperature.
  • DMC dimethyl carbonate
  • one approach is to decompress to distill off by-products as quickly as possible.
  • polycarbonate polyols are usually carried out in a batch process, i.e., component A (polyol and/or lactone), component B (carbonate) and catalyst are charged to the reactor at one time.
  • component A polyol and/or lactone
  • component B carbonate
  • catalyst are charged to the reactor at one time.
  • CN200880116024.6 adopts a method of one-time input of dimethyl carbonate, diethyl carbonate or ethylene carbonate (ethylene carbonate). It is also possible to adopt a method in which a polyol is charged once and a carbonate is continuously fed (CN200410079804.1, CN02813233.5). The fractions in both methods are continuously produced.
  • the carbonate is either a one-time feed or a continuous feed, due to the instability of the composition of the material in the reactor, the amount of carbonate actually involved in the reaction and the amount of carbonate that is theoretically planned to participate in the reaction. There is a certain gap between them, causing significant fluctuations in the molecular weight (hydroxyl value) of the reaction product, which ultimately leads to a decrease in the feasibility of stable production.
  • the prior art is usually corrected by subsequent stoichiometry (or hydroxyl value correction).
  • One of the existing production techniques is to use an excess of carbonate to make the molecular weight higher after the reaction is completed, then test the molecular weight (hydroxyl value) of the product, add the calculated amount of the diol component, and adjust the molecular weight (hydroxyl value). Meet the eligibility requirements (eg CN02813233.5).
  • subsequent corrections require additional production time, which is not conducive to the improvement of labor productivity.
  • a method for controlling the stability of components in the produced fraction is envisaged, and the reaction is carried out under pressure, "by continuously controlling the pressure, keeping the transesterification temperature constant, and controlling the amount of DMC measured, so that preparation
  • the oligocarbonate diol has the desired molar mass and molar mass distribution without the need for subsequent stoichiometric correction.”
  • this method cannot be achieved under normal pressure reactions, and pressurization leads to additional equipment investment and safety measures that are economically disadvantageous.
  • pressurization Even in the case of pressurization, the conditioning ability of the process is not satisfactory, and in its examples, subsequent stoichiometric correction of the hydroxyl value of the product is still required.
  • the present invention provides a novel method for synthesizing polycarbonate polyols in order to solve the problems in the prior art, which can stably produce products satisfying the demand for hydroxyl value, and can avoid cumbersome post-treatment operations.
  • the present invention provides a method for synthesizing a polycarbonate polyol, which comprises transesterifying a raw material A containing a polyol or a mixture of a polyol and a lactone with a carbonate to form the polycarbonate polyol;
  • the raw material A is fed into the reaction system at one time;
  • the stoichiometric predetermined carbonate feed total amount of carbonate is introduced into the reaction system by means of continuous feeding;
  • the byproduct and the carbonate azeotrope are rectified during the reaction;
  • the mass percentage of carbonate in the monitored fraction is sampled during the carbonate feed of the stoichiometric predetermined total carbonate feed; the fines are controlled prior to completion of the stoichiometric predetermined carbonate feed to the carbonate feed.
  • the absolute value of the difference between the mass percentage of the carbonate contained in the fraction and the preset value is ⁇ 2%, and the difference between the maximum value and the minimum value of the mass percentage of the carbonate contained in the fraction is ⁇ 2%;
  • the mass percentage of the carbonate in the rectified fraction is higher or lower than a preset value, and Based on the stoichiometric amount of the predetermined carbonate feed, the corresponding addition or less addition of carbonate to the reaction system, so that the mass of the carbonate used in the reaction actually involved in the formation of the target product is Z1 and theoretically planned to participate in the formation
  • the mass of the carbonates required for the reaction of the target product is consistent or close to each other.
  • the feed rate of the carbonate is controlled to be added to the stoichiometry every hour during the continuous feeding of the carbonate into the reaction system. 1/15-1/2 of the total amount of the predetermined carbonate feed, preferably 1/10-1/3, more preferably 1/8-1/5; using a preferred feed rate, which is advantageous for obtaining a relatively stable Fraction composition, thereby reducing the quality of the carbonate feed that requires subsequent adjustment.
  • the rectified fraction is partially refluxed into the reaction system, and the reflux ratio is controlled to be 1:5 to 20:1, preferably 1:1 to 2:1.
  • the absolute value of the difference between the mass percentage of the carbonate contained in the rectified fraction and the preset value is ⁇ 2%
  • the rectified fraction is The difference between the maximum value and the minimum value of the mass percentage of the carbonate contained is ⁇ 2%.
  • the reflux ratio of the rectified fraction is correspondingly increased or decreased to make the quality of the carbonate contained in the rectified fraction.
  • the absolute value of the difference between the percentage and the preset value is ⁇ 2%, and the difference between the maximum value and the minimum value of the mass percentage of the carbonate contained in the rectification fraction is ⁇ 2%; however, it is not necessary to adjust in this manner, As long as the adjustment method can satisfy the following requirements: the absolute value of the difference between the mass percentage of the carbonate contained in the rectification fraction and the preset value is ⁇ 2%, and the mass percentage of the carbonate contained in the rectification fraction The difference between the maximum and minimum values is ⁇ 2%.
  • the synthesis method comprises the following steps:
  • the mass percentage of the carbonate in the rectified fraction is higher or lower than a preset value, and corresponding to the total amount of the stoichiometric predetermined carbonate feed, correspondingly added or less to the reaction system
  • the carbonate in order to align or approximate the mass Z1 of the carbonate used in the reaction actually involved in the formation of the target product with the mass Z2 of the carbonate required to theoretically participate in the reaction to produce the target product, said Z1 and Z2 Preferably, the following relationship is satisfied:
  • the reaction temperature is controlled to be 160-260 ° C, further preferably 160-200 ° C, more preferably higher than the carbonate.
  • the reaction temperature during the feed to achieve the purpose of promoting the removal of by-products;
  • An inert gas is introduced into the reaction system for stripping, and/or evacuation is performed.
  • the evacuation is to reduce the reaction pressure to 10 kPa or less, more preferably 5 kPa or less.
  • the synthesis method comprises the following steps:
  • reaction temperature is controlled at 160-260 ° C, further preferably 160-200 ° C, more preferably higher than carbonate The reaction temperature during the feed;
  • An inert gas is introduced into the reaction system for stripping, and/or evacuation is performed; preferably, the evacuation is to reduce the reaction pressure to 10 kPa or less, more preferably 5 kPa or less.
  • the relationship between Z1 and Z2 is satisfied as follows:
  • the mass of the carbonate used in the reaction actually participating in the production of the target product can be calculated by calculation based on the amount of carbonate contained in the recovered fraction and the amount of carbonate required to be converted into the amount of by-product contained in the fraction. .
  • the quality of the carbonate participating in the reaction to produce the target product in the reaction system can be maintained and the total amount of carbonate which is theoretically planned to participate in the reaction to produce the target product is relatively close or consistent.
  • the by-products of the present invention mainly refer to small molecules which are detached from the carbonate molecules due to the transesterification of the polyol and the carbonate as planned, for example, when the carbonate is dimethyl carbonate, the by-product is methanol; When it is ethylene carbonate, the by-product is ethylene glycol. In production practice, some volatile small molecules may be produced due to the occurrence of side reactions.
  • the by-products described in the present invention also include such materials, for example, when the raw materials use 1,4-butanediol, side reactions often occur. And tetrahydropyran, when the raw material uses 1,5-pentanediol, side reactions often occur to produce water and tetrahydrofuran, and these volatile small molecules are also rectified and included in by-products.
  • the term "stoichiometric predetermined total carbonate feed amount" as used herein means: according to the mass percentage (or simply referred to as a preset value) of the carbonate contained in the preset rectification fraction, the calculation is based on the participation reaction generation theory. The amount of carbonate consumed by the polycarbonate polyol to be prepared, and the predetermined carbonate feed obtained by summing the two by the amount of carbonate which is not reacted by distillation during the production process. Total amount.
  • the “preset value” is determined according to actual production conditions in actual production, and varies according to factors such as raw materials, reactors, reaction conditions, and the like, and those skilled in the art according to the prior art in the prior art.
  • the preset value of the mass percentage of carbonate contained in the set fraction can be determined by routine experimentation.
  • reaction system using dimethyl carbonate as a raw material of a carbonate when the mass percentage of carbonate in the fraction is higher or lower than a preset value, based on the stoichiometric predetermined total amount of carbonate feed, correspondingly
  • the calculation method for adding or adding less carbonate to the reaction system is: the mass percentage of carbonate contained in the predetermined rectification fraction (ie, "predetermined value") is c, and the fraction is actually taken at different times.
  • the mass percentage of methanol contained in 1,2,3..n is j1,j2,j3,...jn, respectively, and the mass percentage of carbonate is t1, t2, t3,...tn, respectively.
  • the order is m1, m2, m3, ..., mn, respectively, and the calculation process is as follows:
  • the amount of carbonate that should be brought out by the methanol produced by the nth fraction is:
  • the amount of carbonate Cn that the nth fraction should be compensated for is:
  • the amount of carbonate that should be added or added from the first to the nth is:
  • M carbonate correction (t1 * m1 + t2 * m2 + ... + tn * mn) - [(j1 * m1 + j2 * m2 + ... + jn * mn) / (1-c)] * c
  • M carbonate When M carbonate is corrected to a positive value, it indicates that the amount of carbonate actually produced is higher than the amount that should be produced by theoretical calculation. If some carbonate is produced without participating in the reaction, it is necessary to add carbonate. Negative values require less carbonate.
  • the value of methanol involved in the calculation process can be replaced by ethanol; when the raw material is diphenyl carbonate, the corresponding value of methanol is replaced. It is phenol; when the raw material is ethylene carbonate, the corresponding value of methanol is replaced by ethylene glycol; and the like, and will not be further described.
  • the reaction temperature of the transesterification is from 95 to 260 ° C, more preferably from 100 to 220 ° C, still more preferably from 160 to 200 ° C.
  • the raw material A is melted, or the raw material A is melt-mixed with a catalyst, subjected to nitrogen substitution; the temperature is raised to the reaction temperature; and then the stoichiometry is added by continuous feeding.
  • the carbonate of the total amount of carbonate feed is predetermined; in a preferred embodiment, the atmospheric pressure is maintained after the nitrogen replacement.
  • the time required for the carbonate feed is related to the feed rate. In a preferred embodiment, the time required for the carbonate feed is from 2 to 15 hours, further preferably from 3 to 10 hours, more preferably from 5 to 8 hours.
  • the temperature of the reaction system is controlled at 160-260 ° C, preferably 160-200 ° C, more preferably higher. The reaction temperature during the carbonate feed.
  • the synthesis method of the present invention in order to promote the production of by-products, as a preferred embodiment, it is preferred to carry out one or both of the following operations: introducing an inert gas into the reaction system for stripping; or, The pressure of the reaction system is lowered to 10 kPa or less, preferably 5 kPa or less. Preferably, the operation for lowering the pressure is carried out at the end of the reaction, for example, when the amount of the fraction is 90% or more. Those skilled in the art can also employ other existing techniques for promoting the production of by-products.
  • the composition of the produced fraction can be determined by gas chromatography or the like; roughly, the composition of the produced fraction can be monitored by monitoring the temperature of the top of the rectification column in real time; or by using an on-line infrared, high-precision refractometer, etc. monitor. Specific assays and monitoring means for the fraction composition are well known in the art and will not be described in detail.
  • the quality of the produced fraction can be monitored by flow meter, level gauge or weighing.
  • the raw material is diphenyl carbonate
  • no catalyst may be added.
  • the transesterification reaction is carried out in the presence of a catalyst to promote an increase in the reaction rate.
  • the catalyst is preferably fed to the reaction system in a single dose.
  • the catalyst is one or more of an alkali metal compound, an alkaline earth metal compound, an organometallic compound, and an organic amine compound; more preferably sodium hydroxide, sodium methoxide, sodium ethoxide, tetrabutyl titanate, One or more of isopropyl titanate, stannous octoate, triethylamine, pyridine, and N-methylimidazole.
  • the catalyst when the catalyst is one or more of an alkali metal compound, an alkaline earth metal compound, and an organometallic compound, the catalyst is in the obtained polycarbonate polyol based on the corresponding metal element in the catalyst.
  • the mass fraction is ⁇ 100 ppm, preferably ⁇ 25 ppm, more preferably ⁇ 14 ppm; when the catalyst is one or more of organic amine compounds, the catalyst is obtained from the polycarbonate in the catalyst.
  • the mass fraction in the polyol is ⁇ 20 ppm, preferably ⁇ 10 ppm, more preferably ⁇ 5 ppm.
  • the catalyst used in the synthesis method of the present invention is one or both of tetrabutyl titanate and isopropyl titanate.
  • the catalyst is used in an amount of from 1 to 100 ppm, preferably from 4 to 90 ppm, based on the mass of the polycarbonate polyol which is theoretically planned to be produced; or, based on the Ti element in the catalyst, the amount of the catalyst is preferably a theoretically planned polymerization.
  • the product prepared by this preferred embodiment does not require catalyst deactivation (or inactivation) treatment, with a mass of carbonate polyol of 0.7-14 ppm.
  • the polyol is one or more of a C2-C12 diol, a triol and a tetrahydric alcohol, preferably ethylene glycol, diethylene glycol, and 1,2-propanediol.
  • the lactone is preferably one or both of caprolactone or valerolactone.
  • the carbonate is preferably selected from one or more of a dialkyl carbonate, a diaryl carbonate, and an alkylene carbonate; preferably, the carbonate is dimethyl carbonate.
  • the carbonate is dimethyl carbonate.
  • diethyl carbonate and ethylene carbonate are examples of diethyl carbonate and ethylene carbonate.
  • the by-product and the carbonate azeotrope are produced by distillation in a rectification column, and the number of theoretical plates of the rectification column is preferably 10 or more.
  • the obtained polycarbonate polyol product does not require post-treatment; the post-treatment includes any one or more of inactivation, washing, drying, extraction, crystallization, and hydroxyl value correction.
  • the post-treatment includes any one or more of inactivation, washing, drying, extraction, crystallization, and hydroxyl value correction.
  • a second aspect of the invention provides a polycarbonate polyol prepared by the synthetic process described above.
  • the third aspect of the invention provides the use of the polycarbonate polyol prepared by the above-mentioned synthetic method, and the polycarbonate polyol prepared by the invention is particularly suitable for the preparation of a polyurethane product, such as TPU (thermoplastic polyurethane), CPU Polyurethane products such as (casting polyurethane), spandex, synthetic leather, and polyurethane coatings.
  • a polyurethane product such as TPU (thermoplastic polyurethane), CPU Polyurethane products such as (casting polyurethane), spandex, synthetic leather, and polyurethane coatings.
  • the synthesis method of the present invention overcomes the drawbacks of the prior art production of polycarbonate polyols which are unstable and time consuming.
  • the mass percentage of the carbonate in the fraction is monitored, and the stability of the carbonate content in the fraction of the produced fraction is strictly controlled before the completion of the feed, the reaction can be stably carried out, and the reaction speed is fast.
  • the reaction is easy to control.
  • the corresponding percentage of the carbonate in the rectified fraction is higher or lower than a preset value, and the corresponding reaction system is based on the stoichiometric predetermined total carbonate feed amount. Adding or adding less carbonate can stably and efficiently produce products with qualified hydroxyl values.
  • the invention can stably and efficiently produce qualified products, and the product prepared by the invention does not need to be corrected by stoichiometry (that is, the hydroxyl value is corrected or the hydroxyl value is corrected), and the production efficiency is high.
  • the reaction system has less low-boiling carbonates and by-products, and can maintain stable production at a higher temperature (160 ° C or above), thereby increasing the reaction temperature, accelerating the reaction rate, and shortening the reaction time.
  • the reaction can be carried out at a lower catalyst dosage while maintaining the same reaction time.
  • the product prepared by the invention does not require post-treatment or post-treatment, and is free from catalyst inactivation, washing, drying, extraction, crystallization and the like.
  • the pressure described in the present invention is absolute.
  • the synthesis method of the present invention it is not necessary to add a carbonate (such as DMC) or a polyol (such as HDO) according to the calculation of the hydroxyl value of the product after the end of the synthesis reaction as compared with the prior art.
  • the invention does not need to analyze and adjust after all the fractions have been collected, and the fraction can be analyzed in the feeding stage, and the carbonate feed can be adjusted by pre-judging.
  • the preset hydroxyl value of the product is theoretically calculated by formula design; the actual measured hydroxyl value is obtained by chemical titration, specifically referring to the standard HGT. Performed in 2709-1995; Ti residues were obtained by elemental analysis. The mass of the fraction was obtained by weighing with a balance, and the fraction composition was determined by the GC correction factor method, and the mass ratio was obtained.
  • the dimethyl carbonate used in the examples or the comparative examples was from Shida Chemical of Shandong province, and the 1,5-pentanediol and 1,6-hexanediol used were purchased from Ube, Japan, and the neopentyl glycol used was produced from Wanhua Chemical.
  • the isopropyl titanate and tetrabutyl titanate used were purchased from Aladdin.
  • the preset value of the mass percentage of the carbonate contained in the rectified fraction is 32%.
  • the reflux ratio is adjusted according to the following Table 1 to maintain the absolute value of the difference between the mass percentage of the carbonate contained in the rectified fraction and the preset value ⁇ 2%, and the rectification fraction
  • the difference between the maximum value and the minimum value of the mass percentage of carbonate contained in the mixture is ⁇ 2%.
  • the reflux ratio is increased to 2:1.
  • the reflux ratio and fraction quality were recorded at the time of sampling (see Table 1 for the results).
  • the ratio of methanol:DMC in the fraction was determined by the GC correction factor method, and the ratio fluctuated within the range of 67.1:32.9-68.3:31.7 (wt%).
  • the fraction contained 806.0 g of methanol and 384.0 g of dimethyl carbonate.
  • the amount Z1 of the carbonate participating in the reaction was 1132.9 g, and the total mass of the corresponding carbonate and the azeotrope was 1516.9 g.
  • the mass Z2 of the carbonate which is planned to participate in the formation of the target product is 1136.4 g corresponding to 1516.9 g of the carbonate, and the amount of the carbonate to be added is 4.8 g, which is not actually added.
  • ⁇ 100%/Z2 0.3%
  • the product has a preset hydroxyl value of 56.0 mg KOH/g, and the actual sample has a hydroxyl value of 58.2 mg KOH/g. Adjust the product temperature to approximately 100 ° C discharge. The Ti residue in the product was measured to be 13.7 ppm.
  • the preset value of the mass percentage of the carbonate contained in the rectified fraction is 32%.
  • the fraction was continuously recovered at a reflux ratio of 2:1.
  • the quality of the total fraction at the time of sampling is sampled online, and the mass of the total fraction recorded at the previous sampling is sequentially subtracted to obtain the fraction quality of the corresponding stage of sampling, and the methanol in the fraction is estimated accordingly.
  • the quality of dimethyl carbonate (see Table 2 for the results).
  • the methanol:DMC ratio in the fraction fluctuated within the range of 63.0:37.0-68:32.0 (wt%).
  • a total of 25.25 kg of fraction was collected before the end of the continuous feeding of dimethyl carbonate, and 0.78 kg of DMC was added according to the calculation result, and the total amount of the feed was adjusted to 35.78 kg.
  • the temperature was raised to 200 ° C in 75 minutes, and the reaction was continued at 200 ° C for 1.5 hours, and the temperature at the top of the column was observed to decrease.
  • the nitrogen flow rate was turned on at 20 L/h, the system pressure was lowered to 5 kPa or less with an oil pump, and the reaction was continued at 200 ° C for 13 hours. Turn off the vacuum and replenish the nitrogen balance pressure.
  • the fraction contained 16.64 kg of methanol and 8.61 kg of dimethyl carbonate.
  • the amount of carbonate participating in the reaction Z0 was 23.39 kg
  • the total mass of the reaction and azeotrope corresponding to the carbonate was 32.00 kg.
  • the mass Z2 of the carbonate which is planned to participate in the formation of the target product is 23.97 kg corresponding to 32.00 kg of the carbonate
  • the mass Z0 of the carbonate used in the reaction which actually participates in the formation of the target product before the addition is 23.39 kg.
  • the product has a preset hydroxyl value of 56.1 mg KOH/g, and the actual sample has a hydroxyl value of 56.1 mg KOH/g. Adjust the product temperature to approximately 100 ° C discharge. The Ti residue in the product was measured to be 11.4 ppm.
  • the hydroxyl value of the obtained product is expected to reach 72 mgKOH/g, which is largely deviated from the preset hydroxyl value and cannot be used as a qualified product.
  • the preset value of the mass percentage of the carbonate contained in the rectified fraction is 32.0%.
  • the fraction contained 448.2 g of methanol and 227.8 g of dimethyl carbonate.
  • the amount of carbonate participating in the reaction, Z0 was 630.0 g
  • the total mass of the corresponding carbonate and the azeotrope was 857.8 g.
  • the mass Z2 of the carbonate which is planned to participate in the formation of the target product is 642.6 g corresponding to 857.8 g of the carbonate
  • the mass Z0 of the carbonate used in the reaction which actually participates in the formation of the target product before the addition is 630.0 g.
  • the product has a preset hydroxyl value of 112.0 mg KOH/g, and the actual sample has a hydroxyl value of 111.3 mg KOH/g. Adjust the product temperature to approximately 100 ° C discharge. The product Ti residue was measured to be 16.7 ppm.
  • the content of dimethyl carbonate in the fraction is smaller than the preset value. If the operation of adding dimethyl carbonate is not performed, the obtained product has a hydroxyl value of ⁇ 6 compared with the preset hydroxyl value of the product. In this embodiment, the hydroxyl value of the obtained product and the product default hydroxyl value are made closer by the operation of adding dimethyl carbonate.
  • the preset value of the mass percentage of the carbonate contained in the rectified fraction is 32%.
  • the feed was first suspended (198 g had been fed) and refluxed for 1 h, and then the fraction was continuously recovered at a reflux ratio of 1.7:1.
  • the methanol:DMC ratio in the fraction was 67.6:32.4-75.2:24.8. Fluctuations within the wt% range.
  • the composition of the fractions was continuously monitored (see Table 4). According to the results of the analysis of the quality and composition of the first four times of monitoring, 20.6 g of DMC should be added less. After the actual addition of 979.4 g of DMC, the feed was stopped and the fraction was taken. For the analysis, according to the analysis result of the fraction 5, 0.5 g of DMC should be added, and the actual addition is not added.
  • the temperature was raised to 200 ° C in 60 minutes, and the reaction was continued at 200 ° C for 1 hour, and the temperature at the top of the column was observed to decrease.
  • the system pressure was lowered to 3 kPa or less with an oil pump, and the reaction was continued at 200 ° C for 9 hours. Turn off the vacuum and replenish the nitrogen balance pressure.
  • the fraction contained 347.5 g of methanol and 143.5 g of dimethyl carbonate.
  • the amount of carbonate participating in the reaction, Z0 was 488.4 g
  • the total mass of the corresponding carbonate and the azeotrope was 631.9 g.
  • the mass Z2 of the carbonate which is planned to participate in the formation of the target product is 473.4 g corresponding to 631.9 g of the carbonate
  • the mass Z0 of the carbonate used in the reaction which actually participates in the formation of the target product is 488.4 g.
  • the product had a preset hydroxyl value of 112.0 mg KOH/g, and the actual sampling measured a hydroxyl value of 113.1 mg KOH/g. Adjust the product temperature to approximately 100 ° C discharge. The product Ti residue was measured to be 15.0 ppm.
  • the hydroxyl value of the obtained product is expected to be as small as 106 mgKOH/g, and the operation of adding dimethyl carbonate can make the hydroxyl value of the obtained product and the product pre-prepared. Let the hydroxyl value be closer.
  • the preset value of the mass percentage of the carbonate contained in the rectified fraction is 32.5%.
  • 1,789 g of 1,6-hexanediol and 0.1610 g of isopropyl titanate were weighed and added to a glass reactor equipped with an oil bath jacket, a stirrer, a gas inlet, and a rectification column. Vacuum and pass nitrogen three times to maintain normal pressure. Under a nitrogen atmosphere, the temperature was raised to a reaction temperature of 200 ° C, and 1700 g (total amount of a predetermined stoichiometric amount of carbonate feed) of dimethyl carbonate was slowly added dropwise to the system. From the observation of the temperature rise at the top of the column, the fraction was continuously recovered at a reflux ratio of 2:1 to 1:1.
  • the reflux ratio is adjusted according to the following Table 5 to maintain the absolute value of the difference between the mass percentage of the carbonate contained in the rectified fraction and the preset value ⁇ 2%, and the rectification fraction
  • the difference between the maximum value and the minimum value of the mass percentage of carbonate contained in the mixture is ⁇ 2%.
  • the reflux ratio and fraction quality were recorded at the time of sampling (see Table 5 for the results).
  • the ratio of methanol:DMC in the fraction was determined by the GC correction factor method, and the ratio fluctuated within the range of 67.1:32.9-67.7:32.3 (wt%).
  • the reaction was continued at 200 ° C for 1.5 hours, and a decrease in the temperature at the top of the column was observed.
  • the system pressure was lowered to 1 kPa or less with an oil pump, and the reaction was continued at 200 ° C for 12 hours. Turn off the vacuum and replenish the nitrogen balance pressure.
  • the fraction contained 745.6 g of methanol and 362.4 g of dimethyl carbonate.
  • the amount of carbonate participating in the reaction, Z0 was 1048.0 g
  • the total mass of the corresponding carbonate and the azeotrope was 1410.4 g.
  • the mass Z2 of the carbonate which is planned to participate in the formation of the target product is 1050.5 g corresponding to 1410.4 g of the carbonate
  • the mass Z0 of the carbonate used in the reaction which actually participates in the formation of the target product before the addition is 1048.0 g.
  • ⁇ 100%/Z2 0.2%.
  • the product has a preset hydroxyl value of 56.0 mg KOH/g, and the actual sample has a hydroxyl value of 55.5 mg KOH/g. Adjust the product temperature to approximately 100 ° C discharge. The Ti residue in the product was measured to be 11.0 ppm.
  • the content of dimethyl carbonate in the fraction is smaller than the preset value. If the operation of adding dimethyl carbonate is not performed, the obtained product has a hydroxyl value of 57.8 mgKOH/g, which can still be regarded as a qualified product. In the present embodiment, the hydroxyl value of the obtained product is closer to the preset hydroxyl value of the product by the operation of adding dimethyl carbonate.
  • the preset percentage of the mass percentage of the carbonate contained in the rectified fraction was 32%.
  • a 5L glass reactor of the rectification column Vacuum and pass nitrogen three times to maintain normal pressure. Nitrogen gas was introduced at a rate of 0.2 L/h, and the reaction temperature was 95 °C.
  • the fraction is continuously collected at a reflux ratio of 1:1, and the reflux ratio is continuously increased after the temperature rises at the top of the tower, and the maximum increase is 2:1.
  • the methanol:DMC ratio in the fraction was 58:42-68:32 (wt%).
  • the nitrogen flow rate was adjusted to 1 L/h, the system pressure was lowered to 4 kPa or less with an oil pump, and the reaction was continued at 260 ° C for 15 hours. Turn off the vacuum and replenish the nitrogen balance pressure.
  • the product has a preset hydroxyl value of 56.0 mg KOH/g, and the actual sample has a hydroxyl value of 135.76 mg KOH/g. Adjust the product temperature to approximately 100 ° C discharge. The Ti residue in the product was measured to be 13.8 ppm.
  • the preset percentage of the mass percentage of the carbonate contained in the rectified fraction was 32%.
  • 2,0769.8 g of 1,5-pentanediol, 1.77 g of isopropyl titanate, and 21050 g of dimethyl carbonate were weighed and added to a stainless steel reaction vessel equipped with an oil bath jacket, a stirrer, a gas inlet, and a rectification column. Vacuum and pass nitrogen three times to maintain normal pressure.
  • the reaction temperature was 95 °C. The timing was started from the observation of the temperature rise at the top of the column, and the fraction was continuously recovered at a reflux ratio of 3:1, and the temperature was slowly raised.
  • the ratio of methanol:DMC in the fraction was 56:44-64:36.
  • the temperature of the system was continuously increased, and it was raised to 200 ° C in 10 hours, and the reaction was continued at 200 ° C for 2 hours, and the temperature at the top of the column was observed to decrease.
  • the system pressure was lowered to 1 kPa or less with an oil pump, and the reaction was continued at 200 ° C for 10 hours. Turn off the vacuum and replenish the nitrogen balance pressure.
  • the product had a preset hydroxyl value of 112.0 mg KOH/g, and the actual sampling measured a hydroxyl value of 204.9 mg KOH/g. Adjust the product temperature to approximately 100 ° C discharge. The Ti residue in the product was measured to be 12.1 ppm.
  • Comparative Examples 1 and 2 did not employ the method of continuously adding DMC in the examples of the present invention, and the composition of the fractions fluctuated greatly, and the fraction monitoring analysis and the DMC feeding amount compensation were not used, and the hydroxyl value of the product seriously deviated from the preset value.
  • This comparative example is an example of producing an oligocarbonate diol by one-time addition of DMC, as given in Example 3 of the Chinese patent application CN01813544.7.
  • DMC oligocarbonate diol
  • 1890.84 g of hexanediol and 1826.33 g of caprolactone were first reacted in a first stage reaction with a mixture of 281.3 g of DMC and 600.3 g of methanol, and 558.02 g of a DMC/methanol mixture was distilled off at 24.75 h.
  • Comparative Example 3 did not use fraction monitoring analysis and DMC feed amount calculation. There was no timely stop of excessive DMC feed according to the change of fraction composition and feed amount, thus causing excessive DMC to participate in the reaction. The set value is too small and leads to subsequent hydroxyl value correction operations. Comparative Example 3 was significantly prolonged in production time compared to the examples because of multiple operations.
  • the examples 1-5 of the invention have the advantages of stable reaction process, small fluctuation of the fraction of the produced fraction, stable hydroxyl value of the product, no need to adjust the hydroxyl value after the reaction is completed, and the production process is simplified and fast.
  • Example 1 since strict fraction composition control was adopted, there was an advantage that the quality of the carbonate was not required to be adjusted, and the amount of calculation and the amount of operation were reduced, and Example 2-5 had an advantage that the fluctuation of the product index was smaller than that of Example 1.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Materials Engineering (AREA)
  • Wood Science & Technology (AREA)
  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Polyesters Or Polycarbonates (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Abstract

本发明提供一种聚碳酸酯多元醇及其合成方法和应用，该合成方法包括如下步骤：将含有多元醇或多元醇和内酯的混合物的原料A与碳酸酯进行酯交换反应以生成所述聚碳酸酯多元醇，所述原料A一次性投料，采用连续进料的方式将化学计量预定的碳酸酯进料总量的碳酸酯投入反应体系中，反应过程中精馏出副产物和碳酸酯的共沸物；在将化学计量预定的碳酸酯进料总量的碳酸酯投料完成过程中取样监控馏分中碳酸酯的质量百分比，控制采出馏分组成中碳酸酯含量的稳定和/或根据馏分中碳酸酯的含量变化而补加或少加碳酸酯。本发明提供了的方法可快速稳定的生产满足羟值需求的产品，且后处理更为简单。

Description

一种聚碳酸酯多元醇及其合成方法和应用 技术领域
本发明涉及聚碳酸酯多元醇的制备技术领域，特别涉及一种可高效制备聚碳酸酯多元醇的半连续合成方法。
背景技术
聚碳酸酯多元醇是生产聚氨酯的重要原料之一。例如作为聚氨酯弹性体的软链端，具有优异的耐水解、耐热、耐油、耐老化等性能。聚碳酸酯多元醇通常由小分子多元醇或由小分子醇和内酯，和小分子碳酸酯在催化剂下进行酯交换反应，生成聚碳酸酯多元醇和小分子副产物，通过移除小分子副产物而推动反应彻底地进行，进而得到产物。
最主要的聚碳酸酯多元醇产品是以1,6-己二醇(HDO)为原料的均聚或者共聚的聚碳酸酯二元醇。均聚产品只使用1,6-己二醇作为小分子多元醇，共聚产品同时使用2种以上原料，比如1,6-己二醇和1,4-丁二醇(BDO)(日本专利第2885872号说明书)，或者1,6-己二醇和1,5-戊二醇(PDO)(日本专利第1822688号说明书)，或者1,6-己二醇和己内酯/戊内酯(CN01813544.7)。
生产聚碳酸酯多元醇的另一主要原料小分子碳酸酯，主要可以分为碳酸二烷基酯、碳酸二芳基酯、碳酸亚烃酯三类。碳酸二烷基酯比如碳酸二甲酯(DMC)、碳酸二乙酯；碳酸二芳基酯比如碳酸二苯酯；碳酸亚烃酯比如碳酸乙烯酯和碳酸丙烯酯。小分子碳酸酯与小分子醇发生酯交换反应，其中的羰基进入产物，两侧基团转化为副产物，从反应体系中脱去。以碳酸二甲酯为例，会脱去两分子甲醇。由于小分子碳酸酯沸点较低，在反应温度下也有明显气化，因此需要把小分子碳酸酯和副产物及其他化合物的混合物加以精馏分离。通常采出馏分为碳酸酯和副产物的混合物。例如使用碳酸二甲酯时，副产物甲醇与原料碳酸二甲酯共沸，塔顶采出物为共沸混合物。在常压下最低恒沸物的组成比例约为甲醇：碳酸二甲酯＝7：3(质量)，实际采出馏分中 甲醇含量稍低。原料多元醇和产物的沸点较高，在精馏中可以轻易分离回流到反应釜中。
聚碳酸酯多元醇生产中需要产出特定分子量(如1000或2000)，或者采用工业上常用的描述，产出特定羟值(如112mgKOH/g或56mgKOH/g)的产品。因此需要精确计量比例的醇和碳酸酯参与反应。然而，在生产过程中，为了促使反应更快进行，在以碳酸二甲酯(DMC)为原料生产聚碳酸酯多元醇时，一种做法是对体系加压(例如CN200410079804.1)，以利于提升反应温度。而在采用其他原料生产聚碳酸酯多元醇时，一种做法是减压以尽快蒸出副产物。无论加压或减压，都将造成实际参与反应的碳酸酯的量与化学计量预定的碳酸酯总量之间存在较大差距，继而严重影响产品的羟值(分子量)。这一问题，在原料为DMC时显得尤为明显。
生产聚碳酸酯多元醇通常采用间歇工艺，即将组分A(多元醇和/或内酯)，组分B(碳酸酯)和催化剂一次性投入反应釜。如CN200880116024.6即采取一次性投入碳酸二甲酯、碳酸二乙酯或碳酸亚乙酯(碳酸乙烯酯)的方法。也可采取多元醇一次性投料，碳酸酯连续进料的方法(CN200410079804.1，CN02813233.5)。两种方法中馏分都是连续采出的。在这些已知的方法中，碳酸酯无论是一次性进料还是连续进料，由于反应釜内物料组成的不稳定，实际参与反应的碳酸酯与理论上计划参与反应的碳酸酯所需的量之间存在一定差距，造成反应产物的分子量(羟值)都存在显著波动，最终导致稳定生产的可行性降低。
为了保证产物分子量的合格，现有技术通常通过后继化学计量来校正(或称羟值校正)。现有生产技术一种做法是采用加入过量的碳酸酯，使得反应完成后分子量偏高，然后测试产物的分子量(羟值)，补加计算量的二醇组分，调整分子量(羟值)来满足合格要求(例如CN02813233.5)。然而，后继校正需要额外的生产时间，不利于劳动生产率的提高。当然也可以采用在反应接近完成后测试羟值并补加碳酸酯的方法，然而此方法需要再次去封端，更为耗时。
CN200410079804.1中设想了一种控制采出馏分中组分稳定的方法，是在加压条件下进行反应，“通过连续的控制压力，保持酯交换温度不变，控制计量的DMC量，使得制备的低聚碳酸酯二醇具有期望的摩尔质量和摩尔质量分布，不需要后继的化学计量校正”。然而，该方法无法在常压反应下实现，而加压导致额外的设备投资和安全措施，在经济上是不利的。即使在加压情况下，该方法的调节能力也并不理想，在其实施例中仍然需对产物的羟值进行后继化学计量校正。
因此，如何在生产聚碳酸酯多元醇时稳定的生产满足羟值需求的产物且简化后处理操作，是本技术领域亟待取得突破的技术难点之一。
发明内容
本发明为解决现有技术中存在的问题，提供一种新颖的聚碳酸酯多元醇的合成方法，该方法可稳定的生产满足羟值需求的产品，且可避免繁琐的后处理操作。
本发明为达到其目的，采用的技术方案如下：
本发明提供一种聚碳酸酯多元醇的合成方法，该合成方法将含有多元醇或多元醇和内酯的混合物的原料A与碳酸酯进行酯交换反应以生成所述聚碳酸酯多元醇；所述原料A一次性投料至反应体系；采用连续进料的方式将化学计量预定的碳酸酯进料总量的碳酸酯投入反应体系中；反应过程中精馏出副产物和碳酸酯的共沸物；在将化学计量预定的碳酸酯进料总量的碳酸酯投料过程中，取样监控馏分中碳酸酯的质量百分比；在将化学计量预定的碳酸酯进料总量的碳酸酯投料完成之前，控制精馏馏分中所含碳酸酯的质量百分比与预设值的差值的绝对值≤2％，且精馏馏分中所含碳酸酯的质量百分比的最大值和最小值的差值≤2％；和/或，在将化学计量预定的碳酸酯进料总量的碳酸酯投料完成之前，根据精馏馏分中碳酸酯的质量百分比高于或低于预设值，而在所述化学计量预定的碳酸酯进料总量基础上，相应的向反应体系中补加或少加碳酸酯，以使实际参与生成目标产物的反应所使用的碳酸酯的质量Z1与理论上计划参与生成目标产物的反应所需的碳酸 酯的质量Z2之间相一致或接近。
根据本发明的合成方法，在一种优选的实施方案中，以连续进料的方式向反应体系中投入碳酸酯的过程中，所述碳酸酯的进料速度控制在每小时加入所述化学计量预定的碳酸酯进料总量的1/15-1/2，优选为1/10-1/3，更优选为1/8-1/5；采用优选的进料速度，利于获得较为稳定的馏分组成，从而减少需要后续调整的碳酸酯投料质量。
根据本发明的合成方法，优选的，所述精馏馏分部分回流至反应体系中，回流比控制在1:5-20:1，优选1:1-2:1。优选的一种方案中，通过调节所述精馏馏分的回流比，以使精馏馏分中所含碳酸酯的质量百分比与预设值的差值的绝对值≤2％，且精馏馏分中所含碳酸酯的质量百分比的最大值和最小值的差值≤2％。一种具体的优选实施方式中，根据精馏馏分中含有的碳酸酯的质量百分比的上升或下降，相应的提高或降低精馏馏分的回流比，以使精馏馏分中所含碳酸酯的质量百分比与预设值的差值的绝对值≤2％，且精馏馏分中所含碳酸酯的质量百分比的最大值和最小值的差值≤2％；但并非必须按照这种方式进行调节，只要能满足以下要求的调节方式均可：使精馏馏分中所含碳酸酯的质量百分比与预设值的差值的绝对值≤2％，且精馏馏分中所含碳酸酯的质量百分比的最大值和最小值的差值≤2％。
根据本发明合成方法的一种优选的具体实施方式中，所述合成方法包括以下步骤：
(1)将原料A一次性投料至反应体系中，熔融，进行氮气置换，氮气置换后维持常压；升温至酯交换的反应温度，所述反应温度为95-260℃，优选100℃-220℃，更优选160-200℃；
(2)向反应体系中连续投入化学计量预定的碳酸酯进料总量的碳酸酯；在反应过程中精馏副产物和碳酸酯的共沸物，回流部分精馏馏分至反应体系中；在将化学计量预定的碳酸酯进料总量的碳酸酯投料过程中，取样监控馏分中碳酸酯的质量百分比；取样频率可为实时监控或者为每批次反应1-100次，优选为5-10次；控制精馏馏分中所含碳酸酯的质量百分比与预设值的差值的绝对值≤2％，且精馏馏分中所含碳酸酯的质量百分比的最大值和最小值的差值≤2％。优选的， 根据精馏馏分中碳酸酯的质量百分比高于或低于预设值，而在所述化学计量预定的碳酸酯进料总量基础上，相应的向反应体系中补加或少加碳酸酯，以使实际参与生成目标产物的反应所使用的碳酸酯的质量Z1与理论上计划参与生成目标产物的反应所需的碳酸酯的质量Z2之间相一致或接近,所述Z1和Z2之间优选满足如下关系：|Z1-Z2|×100％/Z2≤0.1％；
(3)待碳酸酯进料完成后继续采出馏分，优选的，待碳酸酯进料完成后，控制反应温度为160-260℃，进一步优选为160-200℃，更优选高于碳酸酯进料期间的反应温度，以达到促进副产物脱除的目的；
(4)向反应体系中通入惰性气体进行气提，和/或进行抽真空，优选的，所述抽真空为将反应压力降压到10kPa以下，更优选5kPa以下。
根据本发明合成方法的另一种优选的具体实施方式中，所述合成方法包括以下步骤：
(1)将原料A一次性投料至反应体系中，熔融，进行氮气置换，氮气置换后维持常压；升温至酯交换的反应温度，所述反应温度为95-260℃，优选100℃-220℃，更优选160-200℃；
(2)向反应体系中连续投入化学计量预定的碳酸酯进料总量的碳酸酯；在反应过程中精馏副产物和碳酸酯的共沸物，回流部分精馏馏分至反应体系中；在将化学计量预定的碳酸酯进料总量的碳酸酯投料过程中，取样监控馏分中碳酸酯的质量百分比，并根据精馏馏分中碳酸酯的质量百分比高于或低于预设值，而在所述化学计量预定的碳酸酯进料总量基础上，相应的向反应体系中补加或少加碳酸酯，以使实际参与生成目标产物的反应所使用的碳酸酯的质量Z1与理论上计划参与生成目标产物的反应所需的碳酸酯的质量Z2之间相一致或接近,所述Z1和Z2之间优选满足如下关系：|Z1-Z2|×100％/Z2≤0.1％；
(3)待碳酸酯进料完成后继续采出馏分；优选的，待碳酸酯进料完成后，将反应温度控制在160-260℃，进一步优选为160-200℃，更优选高于碳酸酯进料期间的反应温度；
(4)向反应体系中通入惰性气体进行气提，和/或进行抽真空； 优选的，所述抽真空为将反应压力降压到10kPa以下，更优选5kPa以下。
本发明所述的合成方法，优选的，所述Z1和Z2之间满足如下关系：|Z1-Z2|×100％/Z2≤0.1％。实际参与生成目标产物的反应所使用的碳酸酯的质量可根据已采出馏分中所含的碳酸酯的量、和转化成馏分中所含副产物的量所需的碳酸酯的量通过计算获得。通过本发明的工艺，调控碳酸酯的实际进料总质量，可以维持反应体系中参与反应生产目标产物的碳酸酯的质量和理论上计划参与反应生产目标产物的碳酸酯的总量较为接近或一致，从而利于获得羟值更为稳定的产物，减少或避免羟值的后续校正，提高劳动生产率。而通过控制精馏馏分中所含碳酸酯的质量百分比与预设值的差值的绝对值≤2％，且精馏馏分中所含碳酸酯的质量百分比的最大值和最小值的差值≤2％，可以减少或避免调控碳酸酯的实际进料总量。
文中的“原料A”中的字母A仅仅是为了便于描述及后文引用的便利而采用的代号，并无特定的技术内涵。
本发明所述的副产物主要指由于多元醇与碳酸酯按照计划进行酯交换而从碳酸酯分子上脱离的小分子，例如当碳酸酯为碳酸二甲酯时，副产物为甲醇；当碳酸酯为碳酸乙烯酯时，副产物为乙二醇。生产实践中，由于副反应发生而可能产生某些可挥发的小分子，本发明所述的副产物也包括这类物质，例如当原料使用1,4-丁二醇时往往发生副反应产生水和四氢吡喃，当原料使用1,5-戊二醇时往往发生副反应产生水和四氢呋喃，这些可挥发的小分子也会随之精馏而出，也包括在副产物之中。
文中所述的“化学计量预定的碳酸酯进料总量”是指：根据预设的精馏馏分中所含碳酸酯的质量百分数(或简称为预设值)，计算因参与反应生成理论上计划制备的聚碳酸酯多元醇所消耗的碳酸酯的量，和因生产过程中通过精馏带出的未参与反应的碳酸酯的量，将二者加和而得到的预定的碳酸酯进料总量。所述“预设值”在实际生产中根据实际生产情况而定，根据所用的原料、反应器、反应条件等因素的不同而有所不同，本领域技术人根据其掌握的本领域现有技术可以通 过常规试验来确定所设定的精馏馏分中所含碳酸酯质量百分比的预设值。
以碳酸二甲酯作为碳酸酯原料的反应体系示例，精馏馏分中碳酸酯的质量百分比高于或低于预设值时，在所述化学计量预定的碳酸酯进料总量基础上，相应的向反应体系中补加或少加碳酸酯的量的计算方法是：预设的精馏馏分中所含碳酸酯的质量百分数(即“预设值”)为c，不同时刻实际采出馏分1,2,3..n中所对应含有的甲醇质量百分数依次分别为j1,j2,j3,…jn，碳酸酯质量百分数依次分别为t1,t2,t3,…tn，该阶段采出馏分质量依次分别为m1,m2,m3,…,mn，计算过程如下：
实际采出馏分n中的甲醇质量为M甲醇＝jn*mn
实际采出馏分n中的碳酸酯质量为M碳酸酯＝tn*mn
按照预设值，第n份馏分采出的甲醇理论应带出的碳酸酯的量为：
Mn＝[jn*mn/(1-c)]*c
第n份馏分应补偿的碳酸酯的量Cn为：
Cn＝M碳酸酯-Mn＝tn*mn[jn*mn/(1-c)]*c
所以，从第一份到第n份应多加或者少加的碳酸酯的量为：
M碳酸酯校正＝(t1*m1+t2*m2+…+tn*mn)-[(j1*m1+j2*m2+…+jn*mn)/(1-c)]*c
当M碳酸酯校正为正值，说明实际采出碳酸酯的量高于理论计算应该采出的量，是有部分碳酸酯未经参与反应即被采出，则需要补加碳酸酯，当M为负值则需要少加碳酸酯。
采用其他原料时亦可参照上述计算过程来计算，例如当原料为碳酸二乙酯时，将计算过程中涉及甲醇的数值替换为乙醇即可；原料为碳酸二苯酯时，甲醇的相应数值替换为苯酚；原料为碳酸乙烯酯时，甲醇的相应数值替换为乙二醇；诸如此类，不再一一赘述。
本发明的合成方法，优选的，酯交换的反应温度为95-260℃，进一步优选100℃-220℃，更优选160-200℃。
本发明的合成方法，优选的，将所述原料A熔融，或者将所述原料A与催化剂熔融混合，进行氮气置换；将温度升至所述反应温度； 之后采用连续进料的方式加入化学计量预定的碳酸酯进料总量的碳酸酯；在一种优选的具体实施方式中，在进行所述氮气置换后维持常压。碳酸酯投料所需的时间和进料速度有关，优选方案中，碳酸酯进料所需的时间为2-15小时，进一步优选3-10小时，更优选5-8小时。
本发明的合成方法，优选在碳酸酯进料完成后继续采出馏分，优选的，碳酸酯进料完成后将反应体系的温度控制在160-260℃，优选160-200℃，更优选高于碳酸酯进料期间的反应温度。
本发明的合成方法，为了促进副产物的采出，作为一种优选的具体实施方式，优选进行如下操作中的一种或两种：向反应体系中通入惰性气体进行气提；或者，将反应体系的压力降压至10kPa以下，优选5kPa以下，优选的，降低压力的操作在反应末期进行，例如在馏分采出量达到90％以上时进行。本领域技术人员也可采用其他现有的促进副产物采出的技术手段。
实际生产中，采出馏分的组成可以通过气相色谱等方法确定；粗略地，也可以实时通过监控精馏柱顶温度来监控采出馏分的组成；也可使用在线红外、高精度折光仪等进行监控。馏分组成的具体测定和监控手段是本领域所公知的，对此不做赘述。采出馏分的质量可以通过流量计、液位计或者称重来监控。
本发明的合成方法中，对于反应体系中多元醇原料和产生的低聚物的量没有必要进行调控，因为二者对塔顶馏分组成影响通常小到可以忽略的程度。
本发明的合成方法中，作为一种具体实施方式，当原料为碳酸二苯酯时可不加催化剂。而较为优选的，本发明的合成方法中，所述酯交换反应在催化剂存在下进行，以促使反应速率的提高。所述催化剂优选一次性投料至反应体系中。优选的，所述催化剂为碱金属化合物、碱土金属化合物、有机金属化合物、有机胺类化合物中的一种或多种；更优选为氢氧化钠、甲醇钠、乙醇钠、钛酸四丁酯、钛酸异丙酯、辛酸亚锡、三乙胺、吡啶、N-甲基咪唑中的一种或多种。
本发明的合成方法，当催化剂为碱金属化合物、碱土金属化合物、有机金属化合物中的一种或多种时，以催化剂中相应的金属元素计， 催化剂在所制得的聚碳酸酯多元醇中所占的质量分数≤100ppm，优选≤25ppm，更优选≤14ppm；当催化剂为有机胺类化合物中的一种或多种时，以催化剂中的氮元素计，催化剂在所制得的聚碳酸酯多元醇中所占的质量分数≤20ppm，优选≤10ppm，更优选≤5ppm。
更优选的方案中，本发明的合成方法所用的催化剂为钛酸四丁酯、钛酸异丙酯中的一种或两种。所述催化剂的用量为理论上计划生产的聚碳酸酯多元醇质量的1-100ppm，优选4-90ppm；或，以催化剂中的Ti元素计算，所述催化剂的用量优选为理论上计划生产的聚碳酸酯多元醇质量的0.7-14ppm，采用该优选方案制备的产品无需进行催化剂失活(或称为灭活)处理。
本发明所述的合成方法，所述多元醇为C2-C12的二元醇、三元醇和四元醇中的一种或多种，优选为乙二醇、二甘醇、1,2-丙二醇、1,3-丙二醇、1,3-丁二醇、1,4-丁二醇、2-甲基-1,3-丙二醇、1,2-戊二醇、1,5-戊二醇、1,2-己二醇、1,6-己二醇、新戊二醇、3-甲基-1,5-戊二醇、1,4-环己烷二甲醇、甘油、三羟甲基丙烷、季戊四醇中的一种或多种。
本发明的合成方法，所述内酯优选为己内酯或戊内酯中的一种或两种。
本发明的合成方法中，所述碳酸酯优选选自碳酸二烷基酯、碳酸二芳基酯、碳酸亚烃酯中的一种或多种；优选的，所述碳酸酯为碳酸二甲酯、碳酸二乙酯、碳酸乙烯酯中的一种或多种。
本发明的合成方法，在一种具体实施方式中，其副产物和碳酸酯的共沸物通过精馏柱精馏采出，精馏柱的理论塔板数优选在10块以上。
本领域所公知的，碳酸酯进料和馏分采出不是同时出现的，馏分采出总是在碳酸酯进料达到一定质量后出现，该质量与反应器类型、大小、原料种类、反应温度等工艺条件有关。本发明的合成方法中，可选的，从有馏分产生之时起，暂停进料并进行0.5-2h的馏分全回流，有利于快速实现塔顶采出馏分组成的相对稳定，减少取样调整频率，节省碳酸酯原料，但是并非必须进行该全回流操作。
本发明所述的合成方法，优选的，制得的聚碳酸酯多元醇产品无 需后处理；所述后处理包括灭活、洗涤、干燥、萃取、结晶、羟值校正中的任意一种或多种。
本发明第二方面提供上文所述的合成方法制得的聚碳酸酯多元醇。
本发明第三方面提供上文所述的合成方法制得的聚碳酸酯多元醇的应用，本发明制得的聚碳酸酯多元醇特别适用于聚氨酯产品的制备，例如TPU(热塑性聚氨酯)、CPU(浇筑型聚氨酯)、氨纶、合成革、聚氨酯涂料等聚氨酯产品。
文中所述的“一种或多种”中的“多种”的含义是“两种或多于两种”。
本发明提供的技术方案具有如下有益效果：
本发明的合成方法克服了现有技术中聚碳酸酯多元醇的生产不稳定和耗时长等缺陷。本发明一种方案中，通过碳酸酯连续进料，监控馏分中碳酸酯的质量百分比，在进料完成之前严格控制采出馏分组成中碳酸酯含量的稳定，反应可稳定进行，反应速度较快，反应易于控制。在本发明的又一方案中，根据精馏馏分中碳酸酯的质量百分比高于或低于预设值，而在所述化学计量预定的碳酸酯进料总量基础上，相应的向反应体系中补加或少加碳酸酯，可稳定高效的生产羟值合格的产品。
本发明可稳定高效的生产合格的产品，本发明制得的产物后续无需化学计量校正(即对羟值进行校正，或称羟值校正)，生产效率高。
本发明的合成方法，反应体系中低沸点碳酸酯和副产物较少，可以在更高的温度(160℃或以上)下保持稳定生产，从而可以提高反应温度，加快反应速度，缩短反应时间，或者在维持反应时间不变的情况下，可在较低催化剂用量的情况下反应。
本发明制得的产品无需后处理或后处理比较简单，无需催化剂灭活、洗涤、干燥、萃取、结晶等。
本发明中所述的压力为绝压。
本发明的合成方法，和现有技术相比，无需在合成反应结束后，根据产品羟值计算而补加碳酸酯(如DMC)或者多元醇(如HDO)。本 发明无需待全部馏分收集完毕后再分析调整，可以在进料阶段就进行馏分的分析，通过预判，进而调整碳酸酯的进料。
具体实施方式
为了更好的理解本发明的技术方案，下面结合实施例进一步阐述本发明的内容，但本发明的内容并不仅仅局限于以下实施例。
下面对本发明的实施例或对比例中所用的或可能用到的相关方法进行介绍：产品预设羟值通过配方设计经理论计算而得；实际测定羟值通过化学滴定获得，具体为参照标准HGT 2709-1995进行；Ti残留通过元素分析获得。馏分质量通过天平称重获得，馏分组成以GC校正因子法测定，结果为质量比。以上方法均为本技术领域公知常识，不再一一详细赘述。
实施例或对比例中所用碳酸二甲酯来自山东石大化学，所用1,5-戊二醇、1,6-己二醇均购自日本宇部，所用新戊二醇产自万华化学，所用钛酸异丙酯和钛酸四丁酯均购自阿拉丁。
实施例1
本实施例中，精馏馏分中所含碳酸酯的质量百分比的预设值为32％。
称取1,5-戊二醇1574g，钛酸异丙酯0.1574g，加至装备有油浴夹套、搅拌器、气体入口、精馏柱的玻璃反应釜中。抽真空、通氮气三次，维持常压。氮气保护下，升温到反应温度165℃，向体系中缓慢滴加1700g(化学计量预定的碳酸酯进料总量)碳酸二甲酯。自观察到塔顶温度上升起，以回流比2:1-1:1不断采出馏分。在碳酸二甲酯连续投料过程中，按照如下表1进行回流比的调节，以维持精馏馏分所含碳酸酯的质量百分比与预设值的差值的绝对值≤2％，且精馏馏分中所含碳酸酯的质量百分比的最大值和最小值的差值≤2％。例如，当发现馏分4取样中碳酸酯含量较馏分3有明显上升并且高于预设值时，将回流比增大为2:1。取样时记录回流比、馏分质量(结果见表1)。以GC校正因子法测定馏分中甲醇：DMC的比例，该比例在 67.1:32.9-68.3:31.7(wt％)范围内波动。
碳酸二甲酯滴加完成后(用时8小时)，在1小时内升高到200℃，并在200℃下继续反应1.5小时，观察到塔顶温度下降。用油泵将体系压力降到1kPa以下，并在200℃下继续反应15小时。关闭真空，补充氮气平衡气压。
本实施例中，截至最后一次取样，馏分中含有甲醇806.0g，碳酸二甲酯384.0g。根据甲醇折算，参与反应的碳酸酯的量Z1为1132.9g，反应和共沸合计对应碳酸酯的总质量为1516.9g。理论上，1516.9g碳酸酯对应的，计划参与生成目标产物的碳酸酯的质量Z2为1136.4g，应补加碳酸酯的量为4.8g,实际未补加。|Z1-Z2|×100％/Z2＝0.3％
产品预设羟值56.0mgKOH/g，实际取样测得羟值58.2mgKOH/g。调整产品温度约100℃出料。测得产品中Ti残留13.7ppm。
表1
Figure PCTCN2017118254-appb-000001
实施例2
本实施例中，精馏馏分中所含碳酸酯的质量百分比的预设值为32％。
称取1,5-戊二醇16261g，1,6-己二醇18450g，钛酸四丁酯3.45g，加至装备有油浴夹套、搅拌器、气体入口、精馏柱的不锈钢反应釜中。抽真空、通氮气三次，维持常压。氮气保护下，升温到反应温度156℃，向体系中缓慢滴加35.0kg(化学计量预定的碳酸酯进料总量)碳酸二甲酯。自观察到塔顶温度上升起，以回流比2：1不断采出馏分。在碳酸二甲酯连续投料过程中，在线取样并记录取样时的总馏分质量，依次减去前次取样时记录的总馏分质量而得到取样对应阶段的馏分质量，并依此估算馏分中甲醇和碳酸二甲酯的质量(结果见表2)。馏分中甲醇：DMC比例在63.0:37.0-68:32.0(wt％)范围内波动。在碳酸二甲酯连续投料结束前共收集到25.25kg馏分，根据计算结果补加0.78kg DMC，调整进料总量为35.78kg。
碳酸二甲酯滴加完成(用时15h)后，在75分钟内升高到200℃，并在200℃下继续反应1.5小时，观察到塔顶温度下降。开启氮气流速为20L/h，用油泵将体系压力降到5kPa以下，并在200℃下继续反应13小时。关闭真空，补充氮气平衡气压。
本实施例中，截至最后一次取样，馏分中含有甲醇16.64kg，碳酸二甲酯8.61kg。根据甲醇折算，参与反应的碳酸酯的量Z0为23.39kg，反应和共沸合计对应碳酸酯的总质量为32.00kg。理论上，32.00kg碳酸酯对应的，计划参与生成目标产物的碳酸酯的质量Z2为23.97kg，补加前实际参与生成目标产物的反应所使用的碳酸酯的质量Z0为23.39kg。
由于补加了0.78kg DMC，预期其中0.58kg参与反应，使得补加后实际参与生成目标产物的反应所使用的碳酸酯的质量Z1＝Z0+0.58＝23.97＝Z2。产品预设羟值56.1mgKOH/g，实际取样测得羟值56.1mgKOH/g。调整产品温度约100℃出料。测得产品中Ti残留11.4ppm。
在本实施例中，如果不补加0.78kg DMC，则所得产品的羟值预计会达到72mgKOH/g，与预设羟值偏差较大,不能作为合格产品使用。
表2
Figure PCTCN2017118254-appb-000002
实施例3
本实施例中，精馏馏分中所含碳酸酯的质量百分比的预设值为32.0％。
称取新戊二醇494.2g，1,6-己二醇560.7，钛酸异丙酯0.0988g，加至装备有油浴夹套、搅拌器、气体入口、精馏柱的玻璃反应釜中。抽真空、通氮气三次，维持常压。氮气保护下，升温到反应温度115℃，向体系中缓慢滴加1000g碳酸二甲酯(化学计量预定的碳酸酯进料总量)。自观察到塔顶温度上升起，以回流比1.7:1不断采出馏分，馏分中甲醇：DMC比例在66.1:33.9-66.5:33.5wt％范围内波动。由于反应过程中监测到馏分中碳酸二甲酯含量比预设值偏高(见表3)，追加16.8g碳酸二甲酯，实际共加1016.8g碳酸二甲酯。
碳酸二甲酯滴加完成(用时8h)后，在180分钟内升高到200℃，并在200℃下继续反应1小时，观察到塔顶温度下降。用油泵将体系压力降到3kPa以下，并在200℃下继续反应10小时。关闭真空，补充氮气平衡气压。
本实施例中，截至最后一次取样，馏分中含有甲醇448.2g，碳酸 二甲酯227.8g。根据甲醇折算，参与反应的碳酸酯的量Z0为630.0g，反应和共沸合计对应碳酸酯的总质量为857.8g。理论上，857.8g碳酸酯对应的，计划参与生成目标产物的碳酸酯的质量Z2为642.6g，补加前实际参与生成目标产物的反应所使用的碳酸酯的质量Z0为630.0g。
由于补加了16.8g DMC，预期其中12.6g参与反应，使得补加后实际参与生成目标产物的反应所使用的碳酸酯的质量Z1＝Z0+12.6＝642.6＝Z2。
产品预设羟值112.0mgKOH/g，实际取样测得羟值111.3mgKOH/g。调整产品温度约100℃出料。测得产品Ti残留16.7ppm。
本实施例中馏分中碳酸二甲酯含量比预设值偏差较小，若不进行补加碳酸二甲酯的操作，获得的产品其羟值相比产品预设羟值在±6内，而本实施例通过补加碳酸二甲酯的操作让制得的产品的羟值和产品预设羟值更为接近。
表3
Figure PCTCN2017118254-appb-000003
实施例4
本实施例中，精馏馏分中所含碳酸酯的质量百分比的预设值为 32％。
称取己内酯1565.8g，1,6-己二醇1350.1g，钛酸异丙酯0.2818g，加至装备有油浴夹套、搅拌器、气体入口、精馏柱的玻璃反应釜中。抽真空、通氮气三次，维持常压。氮气保护下，升温到反应温度160℃，向体系中缓慢滴加碳酸二甲酯1000g(化学计量预定的碳酸酯进料总量)。自观察到塔顶温度上升起，首先暂停进料(已进料198g)并全回流1h，然后以回流比1.7:1不断采出馏分，馏分中甲醇：DMC比例在67.6:32.4-75.2:24.8wt％范围内波动。在进料过程中，不断监控馏分组成(见表4)，根据前4次监控所得馏分质量和组成分析结果，应少加20.6g DMC,实际加入979.4g DMC后即停止进料并取馏分5进行分析，根据馏分5分析结果应补加0.5gDMC，实际未补加。
碳酸二甲酯滴加完成(用时4h)后，在60分钟内升高到200℃，并在200℃下继续反应1小时，观察到塔顶温度下降。用油泵将体系压力降到3kPa以下，并在200℃下继续反应9小时。关闭真空，补充氮气平衡气压。
本实施例中，截至最后一次取样，馏分中含有甲醇347.5g，碳酸二甲酯143.5g。根据甲醇折算，参与反应的碳酸酯的量Z0为488.4g，反应和共沸合计对应碳酸酯的总质量为631.9g。理论上，631.9g碳酸酯对应的，计划参与生成目标产物的碳酸酯的质量Z2为473.4g，实际参与生成目标产物的反应所使用的碳酸酯的质量Z0为488.4g。
由于少加了20.6g DMC，折合参与反应的DMC减少15.4g，使得少加后实际参与生成目标产物的反应所使用的碳酸酯的质量Z1＝Z0-15.4＝473.0g,|Z1-Z2|×100％/Z2＝0.08％。
产品预设羟值112.0mgKOH/g，实际取样测得羟值113.1mgKOH/g。调整产品温度约100℃出料。测得产品Ti残留15.0ppm。
在本实施例中，如果不少加20.6g DMC，则所得产品的羟值预计会偏小到106mgKOH/g，而少加碳酸二甲酯的操作可以让制得的产品的羟值和产品预设羟值更为接近。
表4
Figure PCTCN2017118254-appb-000004
实施例5
本实施例中，精馏馏分中所含碳酸酯的质量百分比的预设值为32.5％。
称取1,6-己二醇1789g，钛酸异丙酯0.1610g，加至装备有油浴夹套、搅拌器、气体入口、精馏柱的玻璃反应釜中。抽真空、通氮气三次，维持常压。氮气保护下，升温到反应温度200℃，向体系中缓慢滴加1700g(化学计量预定的碳酸酯进料总量)碳酸二甲酯。自观察到塔顶温度上升起，以回流比2:1-1:1不断采出馏分。在碳酸二甲酯连续投料过程中，按照如下表5进行回流比的调节，以维持精馏馏分所含碳酸酯的质量百分比与预设值的差值的绝对值≤2％，且精馏馏分中所含碳酸酯的质量百分比的最大值和最小值的差值≤2％。取样时记录回流比、馏分质量(结果见表5)。以GC校正因子法测定馏分中甲醇：DMC的比例，该比例在67.1:32.9-67.7:32.3(wt％)范围内波动。
碳酸二甲酯滴加完成后(用时7.5小时)，按照表5的计算结果，追加3.4g碳酸二甲酯，实际共加1703.4g碳酸二甲酯。
在200℃下继续反应1.5小时，观察到塔顶温度下降。用油泵将体系压力降到1kPa以下，并在200℃下继续反应12小时。关闭真空，补充氮气平衡气压。
本实施例中，截至最后一次取样，馏分中含有甲醇745.6g，碳酸二甲酯362.4g。根据甲醇折算，参与反应的碳酸酯的量Z0为1048.0g，反应和共沸合计对应碳酸酯的总质量为1410.4g。理论上，1410.4g碳酸酯对应的，计划参与生成目标产物的碳酸酯的质量Z2为1050.5g，补加前实际参与生成目标产物的反应所使用的碳酸酯的质量Z0为1048.0g。|Z0-Z2|×100％/Z2＝0.2％。
由于补加了3.4g DMC，预期其中2.5g参与反应，使得补加后实际参与生成目标产物的反应所使用的碳酸酯的质量Z1＝Z0+2.5＝Z2。
产品预设羟值56.0mgKOH/g，实际取样测得羟值55.5mgKOH/g。调整产品温度约100℃出料。测得产品中Ti残留11.0ppm。
本实施例中馏分中碳酸二甲酯含量比预设值偏差较小，若不进行补加碳酸二甲酯的操作，获得的产品其羟值预计为57.8mgKOH/g，仍可视为合格产品，而本实施例通过补加碳酸二甲酯的操作让制得的产品的羟值和产品预设羟值更为接近。
表5
Figure PCTCN2017118254-appb-000005
对比例1
本对比例中，精馏馏分中所含碳酸酯的质量百分比的预设值为32％。称取1,5-戊二醇864.8g，1,6-己二醇981.2g，钛酸异丙酯0.1730g，碳酸二甲酯1750g，加至装备有油浴夹套、搅拌器、气体入口、精馏柱的5L玻璃反应釜中。抽真空、通氮气三次，维持常压。以0.2L/h的速度通入氮气，反应温度95℃。自观察到塔顶温度上升起开始计时，以回流比1:1不断采出馏分，并在塔顶温度上升后不断增大回流比，最大增大到2:1。馏分中甲醇：DMC比例为58:42-68:32(wt％)。随着反应进行不断提升体系温度，在8小时内升高到260℃，并在260℃下继续反应2小时，观察到塔顶温度下降。调整氮气流速为1L/h，用油泵将体系压力降到4kPa以下，并在260℃下继续反应15小时。关闭真空，补充氮气平衡气压。
产品预设羟值56.0mgKOH/g，实际取样测得羟值135.76mgKOH/g。调整产品温度约100℃出料。测得产品中Ti残留13.8ppm。
对比例2
本对比例中，精馏馏分中所含碳酸酯的质量百分比的预设值为32％。称取1,5-戊二醇20769.8g，钛酸异丙酯1.77g，碳酸二甲酯21050g，加至装备有油浴夹套、搅拌器、气体入口、精馏柱的不锈钢反应釜中。抽真空、通氮气三次，维持常压。反应温度95℃。自观察到塔顶温度上升起开始计时，以回流比3:1不断采出馏分，并缓慢提升温度，馏分中甲醇：DMC比例为56:44-64:36。随着反应进行不断提升体系温度，在10小时内升高到200℃，并在200℃下继续反应2小时，观察到塔顶温度下降。用油泵将体系压力降到1kPa以下，并在200℃下继续反应10小时。关闭真空，补充氮气平衡气压。
产品预设羟值112.0mgKOH/g，实际取样测得羟值204.9mgKOH/g。调整产品温度约100℃出料。测得产品中Ti残留12.1ppm。
对比例1和2没有采用本发明实施例中的连续加入DMC的方法，其馏分组成波动大，并且没有采用馏分监控分析和DMC投料量补偿，其产品羟值严重偏离预设值。
对比例3
该对比例为中国专利申请CN01813544.7的实施例3给出的通过一次加入DMC生产低聚碳酸酯二醇的例子。按照该文献中的实施例3，1890.84g己二醇和1826.33g己内酯首先在第一级反应中与281.3gDMC和600.3g甲醇的混合物反应，用时24.75h蒸馏出558.02g的DMC/甲醇混合物，含6.43％的DMC；在第二级反应中加入1380.07gDMC，用时15h或更久，蒸馏出1007.00g的DMC/甲醇混合物，含32.21％的DMC。计算表明DMC过量39.97g。所得产品羟值37mgKOH/g，低于预设目标(估计为56mgKOH/g)。
按照中国专利申请CN01813544.7，其中的实施例4对实施例3所得产品进行了羟值调整,补加己二醇和己内酯并反应5小时。
对比例3没有采用馏分监控分析和DMC投料量核算，没有根据馏分组成和进料量的变化及时停止过多的DMC进料，因此导致过多的DMC参与反应，反应完成后产品羟值比预设值偏小，并且导致了后续的羟值校正操作。对比例3因为多次操作，生产用时相比实施例有明显延长。
相比对比例，本发明的实施例1-5具有反应过程稳定、采出馏分组成波动小、产品羟值稳定，反应完成后无需羟值调整、生产工艺简化快速等优点。实施例1由于采取了严格的馏分组成控制，具有无需调整碳酸酯质量的优点，减少了计算量和操作量，实施例2-5相比实施例1有产品指标波动更小的优点。
本领域技术人员可以理解，在本说明书的教导之下，可对本发明做出一些修改或调整。这些修改或调整也应当在本发明权利要求所限定的范围之内。

Claims (14)

  1. 一种聚碳酸酯多元醇的合成方法，其特征在于，将含有多元醇或多元醇和内酯的混合物的原料A与碳酸酯进行酯交换反应以生成所述聚碳酸酯多元醇；
    所述原料A一次性投料至反应体系；
    采用连续进料的方式将化学计量预定的碳酸酯进料总量的碳酸酯投入反应体系中；
    反应过程中精馏出副产物和碳酸酯的共沸物；
    在将化学计量预定的碳酸酯进料总量的碳酸酯投料过程中，取样监控馏分中碳酸酯的质量百分比；
    在将化学计量预定的碳酸酯进料总量的碳酸酯投料完成之前，控制精馏馏分中所含碳酸酯的质量百分比与预设值的差值的绝对值≤2％，且精馏馏分中所含碳酸酯的质量百分比的最大值和最小值的差值≤2％；
    和/或，在将化学计量预定的碳酸酯进料总量的碳酸酯投料完成之前，根据精馏馏分中碳酸酯的质量百分比高于或低于预设值，而在所述化学计量预定的碳酸酯进料总量基础上，相应的向反应体系中补加或少加碳酸酯，以使实际参与生成目标产物的反应所使用的碳酸酯的质量Z1与理论上计划参与生成目标产物的反应所需的碳酸酯的质量Z2之间相一致或接近。
  2. 根据权利要求1所述的合成方法，其特征在于,以连续进料的方式向反应体系中投入碳酸酯的过程中，所述碳酸酯的进料速度控制在每小时加入所述化学计量预定的碳酸酯进料总量的1/15-1/2，优选为1/10-1/3，更优选为1/8-1/5。
  3. 根据权利要求1-2任一项所述的合成方法，其特征在于，精馏馏分部分回流至反应体系中，回流比控制在1:5-20:1，优选1:1-2:1；
    优选的，调节所述精馏馏分的回流比，以使精馏馏分中所含碳酸酯的质量百分比与预设值的差值的绝对值≤2％，且精馏馏分中所含碳酸酯的质量百分比的最大值和最小值的差值≤2％；
    进一步优选的，根据精馏馏分中含有的碳酸酯的质量百分比的上升或下降，相应的提高或降低精馏馏分的回流比，以使精馏馏分中所含碳酸酯的质量百分比与预设值的差值的绝对值≤2％，且精馏馏分中所含碳酸酯的质量百分比的最大值和最小值的差值≤2％。
  4. 根据权利要求1-3任一项所述的合成方法，其特征在于，所述合成方法包括以下步骤：
    (1)将原料A一次性投料至反应体系中，熔融，进行氮气置换，氮气置换后维持常压；升温至酯交换的反应温度，所述反应温度为95-260℃，优选100℃-220℃，更优选160-200℃；
    (2)向反应体系中连续投入化学计量预定的碳酸酯进料总量的碳酸酯；在反应过程中精馏副产物和碳酸酯的共沸物，回流部分精馏馏分至反应体系中；在将化学计量预定的碳酸酯进料总量的碳酸酯投料过程中，取样监控馏分中碳酸酯的质量百分比，控制精馏馏分中所含碳酸酯的质量百分比与预设值的差值的绝对值≤2％，且精馏馏分中所含碳酸酯的质量百分比的最大值和最小值的差值≤2％；
    优选地，根据精馏馏分中碳酸酯的质量百分比高于或低于预设值，而在所述化学计量预定的碳酸酯进料总量基础上，相应的向反应体系中补加或少加碳酸酯，以使实际参与生成目标产物的反应所使用的碳酸酯的质量Z1与理论上计划参与生成目标产物的反应所需的碳酸酯的质量Z2之间相一致或接近；
    (3)待碳酸酯进料完成后继续采出馏分；优选的，待碳酸酯进料完成后，将反应温度控制在160-260℃，进一步优选为160-200℃；
    (4)向反应体系中通入惰性气体进行气提，和/或进行抽真空；优选的，所述抽真空为将反应压力降压到10kPa以下，更优选5kPa以下。
  5. 根据权利要求1-4任一项所述的合成方法，其特征在于，所述取样监控馏分中碳酸酯的质量百分比，为实时监控或者每批次反应的取样监控频率为1-100次，优选5-10次。
  6. 根据权利要求1-5任一项所述的合成方法，其特征在于，所述Z1和Z2之间满足如下关系：|Z1-Z2|×100％/Z2≤0.1％。
  7. 根据权利要求1-6任一项所述的合成方法，其特征在于，所述酯交换反应在催化剂存在下进行，所述催化剂一次性投料至反应体系中；
    优选的，所述催化剂为碱金属化合物、碱土金属化合物、有机金属化合物、有机胺类化合物中的一种或多种；更优选为氢氧化钠、甲醇钠、乙醇钠、钛酸四丁酯、钛酸异丙酯、辛酸亚锡、三乙胺、吡啶、N-甲基咪唑中的一种或多种。
  8. 根据权利要求7所述的合成方法，其特征在于，当催化剂为碱金属化合物、碱土金属化合物、有机金属化合物中的一种或多种时，以催化剂中相应的金属元素计，催化剂在所制得的聚碳酸酯多元醇中所占的质量分数≤100ppm，优选≤25ppm，更优选≤14ppm；
    当催化剂为有机胺类化合物中的一种或多种时，以催化剂中的氮元素计，催化剂在所制得的聚碳酸酯多元醇中所占的质量分数≤20ppm，优选≤10ppm，更优选≤5ppm。
  9. 根据权利要求7所述的合成方法，其特征在于，所述催化剂为钛酸四丁酯、钛酸异丙酯中的一种或两种，所述催化剂的用量为理论上计划生产的聚碳酸酯多元醇质量的1-100ppm，优选4-90ppm；或，以催化剂中的Ti元素计算，所述催化剂的用量为理论上计划生产的聚碳酸酯多元醇质量的0.7-14ppm。
  10. 根据权利要求1-9任一项所述的合成方法，其特征在于，所述多元醇为C2-C12的二元醇、三元醇和四元醇中的一种或多种，优选为乙二醇、二甘醇、1,2-丙二醇、1,3-丙二醇、1,3-丁二醇、1,4-丁二醇、2-甲基-1,3-丙二醇、1,2-戊二醇、1,5-戊二醇、1,2-己二醇、1,6-己二醇、新戊二醇、3-甲基-1,5-戊二醇、1,4-环己烷二甲醇、甘油、三羟甲基丙烷、季戊四醇中的一种或多种；
    所述内酯为己内酯或戊内酯中的一种或两种；
    所述碳酸酯选自碳酸二烷基酯、碳酸二芳基酯、碳酸亚烃酯中的一种或多种；优选的，所述碳酸酯为碳酸二甲酯、碳酸二乙酯、碳酸乙烯酯中的一种或多种。
  11. 根据权利要求1-10任一项所述的合成方法，其特征在于， 从有精馏馏分产生之时起，暂停碳酸酯的进料并进行0.5-2h的精馏馏分全回流。
  12. 根据权利要求1-11任一项所述的合成方法，其特征在于，制得的聚碳酸酯多元醇产品无需后处理；所述后处理包括灭活、洗涤、干燥、萃取、结晶、羟值校正中的任意一种或多种。
  13. 一种根据权利要求1-12任一项所述的合成方法制得的聚碳酸酯多元醇。
  14. 权利要求1-12任一项所述的合成方法制得的聚碳酸酯多元醇的应用，其特征在于，应用于聚氨酯产品的制备，所述聚氨酯产品优选包括TPU、CPU、氨纶、合成革、聚氨酯涂料中的一种或多种。
PCT/CN2017/118254 2017-12-21 2017-12-25 一种聚碳酸酯多元醇及其合成方法和应用 WO2019119466A1 (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP17935128.3A EP3730535A4 (en) 2017-12-21 2017-12-25 POLYCARBONATE-POLYOL, ITS SYNTHESIS PROCESS AND ITS USE

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201711394969.1A CN109957101B (zh) 2017-12-21 2017-12-21 一种聚碳酸酯多元醇及其合成方法和应用
CN201711394969.1 2017-12-21

Publications (1)

Publication Number Publication Date
WO2019119466A1 true WO2019119466A1 (zh) 2019-06-27

Family

ID=66994417

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2017/118254 WO2019119466A1 (zh) 2017-12-21 2017-12-25 一种聚碳酸酯多元醇及其合成方法和应用

Country Status (3)

Country Link
EP (1) EP3730535A4 (zh)
CN (1) CN109957101B (zh)
WO (1) WO2019119466A1 (zh)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113637150B (zh) * 2021-08-16 2023-09-12 佛山市中天融新材料科技有限公司 聚碳酸酯二元醇及其制备方法和应用

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2885872B2 (ja) 1990-04-24 1999-04-26 旭化成工業株式会社 脂肪族コポリカーボネート及び該単位を含有するポリウレタン
JP2001270938A (ja) * 2000-01-21 2001-10-02 Ube Ind Ltd ポリカーボネートジオールの製造方法
US20010047073A1 (en) * 2000-03-17 2001-11-29 Enichem S.P.A. Process for the preparation of polycarbonate diols with a high molecular weight
CN1444618A (zh) * 2000-06-06 2003-09-24 拜尔公司 生产脂肪族低聚碳酸酯二醇的方法
CN1522270A (zh) * 2001-06-27 2004-08-18 一种制备脂肪族低聚碳酸酯二醇的方法
CN1616407A (zh) * 2003-09-19 2005-05-18 拜尔材料科学股份公司 制备脂肪族低聚碳酸酯二醇的方法

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19829593A1 (de) * 1998-07-02 2000-01-05 Henkel Kgaa Verfahren zur Herstellung von Verbindungen mit terminalen OH-Gruppen
US8168728B2 (en) * 2007-11-16 2012-05-01 Asahi Kasei Chemicals Corporation Polycarbonate diol with ease of reaction stabilization

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2885872B2 (ja) 1990-04-24 1999-04-26 旭化成工業株式会社 脂肪族コポリカーボネート及び該単位を含有するポリウレタン
JP2001270938A (ja) * 2000-01-21 2001-10-02 Ube Ind Ltd ポリカーボネートジオールの製造方法
US20010047073A1 (en) * 2000-03-17 2001-11-29 Enichem S.P.A. Process for the preparation of polycarbonate diols with a high molecular weight
CN1444618A (zh) * 2000-06-06 2003-09-24 拜尔公司 生产脂肪族低聚碳酸酯二醇的方法
CN1522270A (zh) * 2001-06-27 2004-08-18 一种制备脂肪族低聚碳酸酯二醇的方法
CN1616407A (zh) * 2003-09-19 2005-05-18 拜尔材料科学股份公司 制备脂肪族低聚碳酸酯二醇的方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP3730535A4 *

Also Published As

Publication number Publication date
EP3730535A1 (en) 2020-10-28
CN109957101B (zh) 2020-07-28
CN109957101A (zh) 2019-07-02
EP3730535A4 (en) 2021-08-25

Similar Documents

Publication Publication Date Title
EP3124503B1 (en) Method for producing hydrogenated petroleum resin
JP4288155B2 (ja) 脂肪族オリゴカーボネートジオールの製造方法
CN109107207B (zh) 一种带有外循环系统的反应精馏装置及其应用
US7420077B2 (en) Preparation of aliphatic oligocarbonate diols
CN112225857B (zh) 一种色度稳定的含异氰脲酸酯的多异氰酸酯组合物及其制备方法
ITMI20000549A1 (it) Procedimento per la preparazione di policarbonato dioli ad elevato peso molecolare
CN109400860B (zh) 一种分子量可控的聚碳酸酯二醇的制备方法
JP2008505230A (ja) 末端二級ヒドロキシル基を含有するオリゴカーボネートポリオール
WO2019119466A1 (zh) 一种聚碳酸酯多元醇及其合成方法和应用
JP2017014427A (ja) ポリカーボネートポリオール、及びポリウレタン
KR100810123B1 (ko) 조 에틸렌카보네이트로부터 고순도 및 고수율의에틸렌카보네이트의 정제방법
JP2003535936A5 (zh)
WO2001094444A1 (de) Verfahren zur herstellung von aliphatischen oligocarbonatdiolen
JPH0525264A (ja) 反応性安定化ポリオール
JP5614637B2 (ja) ポリカーボネートポリオールおよびその製造方法
EP2028177A1 (en) Process for preparing aminobenzoate esters
JP4961104B2 (ja) 脂肪族オリゴカーボネートポリオールの製造方法
CN107987268A (zh) 一种使用双催化剂生产聚碳酸酯多元醇的合成方法
US20160326316A1 (en) Improved polytetramethylene ether glycol manufacturing process
EP3165552B1 (en) Polycarbonates, polyurethanes, elastomers, processes for manufacturing polycarbonates, and processes for manufacturing polyurethanes
JP2008121029A (ja) ウレタン化触媒含有ポリカーボネートジオールの製造方法
CN110183627B (zh) 一种尼龙酸聚酯多元醇的制备方法及其产品
JP4514396B2 (ja) ポリトリメチレンカーボネートジオールの製造法
CN114671845B (zh) 碳酸亚乙烯酯的制备方法
JP5069855B2 (ja) 脂環式オレフィン多価カーボネート化合物の製造方法および脂環式オレフィン多価カーボネート化合物の混合物

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 17935128

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 2017935128

Country of ref document: EP

Effective date: 20200721