Method for producing poly (butylene succinate) polyester by taking C4 unsaturated binary oxygen-containing compound as raw material

Abstract

The invention provides a method for producing poly (butylene succinate) polyester by taking a C4 unsaturated binary oxygen-containing compound as a raw material, which comprises the following steps: by taking C4 unsaturated diol and C4 saturated or unsaturated diacid or anhydride or ester thereof as raw materials, carrying out copolymerization on the C4 unsaturated diol and the C4 saturated or unsaturated diacid or anhydride or ester in the presence or absence of a copolymerization modifier; the poly (butylene succinate) polyester is synthesized by two steps of esterification / ester exchange-hydrogenation coupling reaction and reactive distillation-polycondensation reaction. According to the invention, a solid acid loaded metal bifunctional catalyst or an acid-metal composite catalyst with esterification / ester exchange-hydrogenation functions and a continuous reaction-separation process are adopted to prepare a polyester precursor butanediol succinate or modified ester; and then the poly (butylene succinate) polyester is prepared by adopting a polymerization catalyst and a continuous reaction distillation-polycondensation process, so that the link of preparing monomers 1, 4-butanediol and succinic acid or anhydride or ester is omitted. The method adopts basic chemical raw materials, and is short in process flow, low in device investment, low in material consumption and energy consumption, low in production cost and clean and environment-friendly in process.

Description

Technical Field

[0001] The present invention relates to the technology for manufacturing biodegradable plastics, specifically including a method for producing polybutylene succinate-based polyesters using C 4 unsaturated dibasic oxygen-containing compounds as raw materials. Background Art

[0002] Polybutylene succinate-based polyesters, such as polybutylene succinate (PBS), polybutylene succinate adipate (PBSA), polybutylene succinate terephthalate 1,4-butanediol ester (PBST), polybutylene succinate 2,5-furandicarboxylate 1,4-butanediol ester (PBSF), polybutylene succinate 1,4-butanediol 1,4-cyclohexanedimethanol ester (PBCS), polybutylene succinate butanediol trimethylolpropane ester (PBTS), polybutylene succinate glycolic acid butanediol ester (PBGS), polybutylene succinate lactic acid butanediol ester (PBLS), and polybutylene succinate butanediol-poly(lactic acid) block copolyester (PBS-co-PLA), etc., are a class of biodegradable plastics with excellent properties and broad development prospects.

[0003] Currently, the synthesis methods of polybutylene succinate-based polyesters mainly include three methods: succinic acid esterification polycondensation method, succinic acid ester transesterification polycondensation method, and succinic anhydride ring-opening polycondensation method. Using succinic acid, succinic acid ester, and succinic anhydride and 1,4-butanediol (BDO) as the main monomer raw materials, with or without the addition of a third monomer, through esterification, transesterification, and ring-opening reactions, the polyester precursor butylene succinate or modified ester is first synthesized, and then the precursor is polycondensed to prepare polybutylene succinate or modified copolyester. Obviously, whether it is the esterification polycondensation method, the transesterification polycondensation method, or the ring-opening polycondensation method, it is necessary to first prepare the acid monomers succinic acid, succinic acid ester, and succinic anhydride and the alcohol monomer BDO.

[0004] Generally, in industry, basic raw materials are used to produce high-purity polymer monomers. For example, maleic anhydride is selectively hydrogenated to produce succinic anhydride (CN113045519B), and then succinic anhydride is hydrolyzed to produce succinic acid (CN102311332B) or esterified with lower alkanols such as methanol to produce alkyl succinates (CN112694602B); or maleic anhydride is first esterified with lower alkanols to produce alkyl maleates, and then hydrogenated and saturated to produce alkyl succinates (CN110563933B), and then alkyl succinates are hydrolyzed to produce succinic acid (CN102746138B). In the industrial production of BDO, internationally, the main method is to directly hydrogenate maleic anhydride to co-produce succinic anhydride and γ-butyrolactone, and after separating succinic anhydride, γ-butyrolactone is further hydrogenated to co-produce tetrahydrofuran and BDO (CN114181038B), or maleic anhydride is first esterified and hydrogenated to produce dimethyl succinate, and then further hydrogenated to co-produce γ-butyrolactone, tetrahydrofuran and BDO (CN113512183A); in China, the main method for producing BDO is the acetylenic aldehyde method, in which butynediol obtained by condensing acetylene and formaldehyde is hydrogenated to produce butenediol, and then butenediol is further hydrogenated to produce BDO (CN1172792A and CN110483242B). It can be seen that in the production of polybutylene succinate monomers, only succinic anhydride is obtained by one-step hydrogenation of maleic anhydride, and the rest of the monomers need to go through a cumbersome process of multiple reactions and multiple separation and purification steps to obtain.

[0005] In the existing production technologies of polybutylene succinate, due to the existence of an esterification reaction equilibrium, the reaction conditions of the succinic acid esterification polycondensation method are relatively harsh, such as relatively high reaction temperature and vacuum degree, and there are problems such as low esterification reaction rate, incomplete reaction of acidic monomers such as succinic acid, a large amount of by-products such as tetrahydrofuran generated by the cycloetherification of alcohol monomers such as BDO, and a large amount of wastewater generated by the esterification-polycondensation reaction, resulting in low raw material utilization rate, high raw material consumption and energy consumption, low product yield, large amount of wastewater and high treatment cost, which increases the production cost of the polyester. The succinic acid ester transesterification polycondensation method also has an ester transesterification reaction equilibrium. Compared with the esterification polycondensation method, the reaction temperature and vacuum degree are milder, but due to the generation of a large amount of alkanols during the transesterification process, its monomer synthesis route is longer, the raw material utilization rate is lower, and the raw material consumption, energy consumption and production cost are higher. Although the succinic anhydride ring-opening polycondensation method uses succinic anhydride as the monomer, shortening the monomer preparation process and reducing the monomer manufacturing cost, and there is no chemical equilibrium in the ring-opening esterification reaction, the esterification rate is high and the speed is faster, and the generation amount of small molecules such as water and tetrahydrofuran during the esterification polycondensation synthesis of polyester is reduced by at least half, the monomer raw material consumption is low, the production process is cleaner, and both the product quality and production cost have been greatly improved. However, like the esterification polycondensation method and the transesterification polycondensation method, its alcohol monomers also need to go through multiple steps to obtain, and small molecules such as water and tetrahydrofuran are still generated during the polycondensation process, and the contribution value of this method to reducing the production cost of polybutylene succinate is limited.

[0006] For example, Patent CN114920913B provides a method for catalytic conversion of maleic anhydride to prepare PBS. First, maleic anhydride is hydrogenated to convert it into succinic anhydride and γ-butyrolactone. After separating succinic anhydride, γ-butyrolactone is then hydrogenated to prepare BDO and tetrahydrofuran, and BDO is separated. Then, succinic anhydride and BDO undergo a polymerization reaction to produce the product PBS. In the first step of hydrogenation in this patent, a co-production process of succinic anhydride and γ-butyrolactone is adopted, and the selectivity of the target product succinic anhydride is less than 50%; in the second step of hydrogenation reaction, a co-production process of tetrahydrofuran and BDO is adopted; in the third step, succinic anhydride and BDO undergo ring-opening polycondensation to synthesize PBS. It can be seen that the process for preparing BDO by hydrogenating maleic anhydride in this patent is a co-production process. Although the monomer succinic anhydride and BDO are obtained, there are many by-products and the separation process is complex, resulting in increased investment and production costs.

[0007] Another example is that Patents CN112694602B and CN110563933B provide a method for producing PBS from maleic anhydride via succinic acid esters. Maleic anhydride is hydrogenated to prepare succinic anhydride, and then succinic anhydride is esterified with a lower aliphatic monohydric alcohol to prepare succinic acid diester, or maleic anhydride is esterified with a lower aliphatic monohydric alcohol to prepare maleic acid diester, which is then hydrogenated to prepare succinic acid diester. Then, succinic acid diester and BDO are synthesized into PBS by transesterification polycondensation. Patent CN106366297B discloses a preparation method for the overall industrial chain of polybutylene succinate. Using liquid-phase maleic anhydride as a raw material to produce succinic anhydride, and then through ring-opening esterification of succinic anhydride and BDO to prepare a polyester precursor, and then carrying out a polycondensation reaction under vacuum conditions to obtain the target product PBS. Obviously, although these patents propose methods for preparing PBS from maleic anhydride as a raw material, they do not solve the source problem of another key monomer BDO required for preparing PBS, and still adopt multiple steps such as first synthesizing an acidic monomer, then preparing a polyester precursor, and then polycondensing the precursor to synthesize a polyester. The process flow is long, and there are still the aforementioned disadvantages of preparing polybutylene succinate.

[0008] Therefore, the existing technologies for producing polybutylene succinate starting from basic chemical raw materials such as maleic anhydride and butynediol all require multiple reaction and separation and purification processes such as monomer production, precursor preparation, and polyester synthesis. The process flow is long, the equipment investment is high, the operation is cumbersome, and a large amount of by-products and wastewater are generated, resulting in high energy consumption and low effective utilization rate of raw materials, making the production cost of polybutylene succinate polyester remain high and lacking market competitiveness. If the synthesis path can be completely changed through technological innovation and the multiple steps of preparing acid monomers and alcohol monomers and synthesizing polyester precursors are integrated into one step, the production cost of polybutylene succinate polyester will be greatly reduced.

[0009] At present, poly(butylene succinate) polyesters, as biodegradable plastics, have been widely recognized for their excellent properties. However, due to their production costs and selling prices still being much higher than those of traditional plastics such as PP and PE, there are still obstacles to large-scale promotion and application, the market acceptance is still low, and there is still a lack of market competitiveness with polyolefin plastics. Reducing the manufacturing cost of polybutylene succinate has become a "bottleneck" problem for its replacement of traditional plastics and the realization of large-scale production and application. Improving and optimizing the single-step manufacturing technology of monomers or polyesters has limited room for reducing the manufacturing cost of polyesters. In order to further reduce the comprehensive manufacturing cost of polyesters, it is necessary to conduct an integrated innovation of the overall process from the manufacturing of raw materials to the manufacturing of polyesters. Synthesizing polyester precursors directly from basic raw materials in one step, omitting the cumbersome processes of traditional monomer synthesis reactions, separation and purification, and then synthesizing polyester precursors from monomers, can greatly shorten the process flow and reduce the manufacturing cost of polyesters. Therefore, an integrated green, efficient, and low-cost overall synthesis process integrating the multi-step processes of manufacturing monomers from basic raw materials, preparing precursors from monomers, and synthesizing polyester materials from precursors has important practical significance for minimizing the manufacturing cost of poly(butylene succinate) polyesters. Summary of the Invention

[0010] In view of this, the present invention provides an overall synthesis process route and production method for poly(butylene succinate) polyesters with a short process flow, high efficiency, excellent quality, and low cost.

[0011] To achieve the above object, the technical solution of the present invention is specifically as follows:

[0012] A method for producing poly(butylene succinate) polyesters using C 4 unsaturated dioxygen-containing compounds as raw materials, comprising the following steps:

[0013] (1) In a fixed-bed or slurry-bed reactor, in the presence of a solid acid-supported metal bifunctional catalyst or an acid-metal composite catalyst, using C 4 unsaturated diols and C 4 dicarboxylic acids and / or their anhydrides or / and their esters as raw materials, with or without adding a copolymerization modifier, through esterification-hydrogenation or transesterification-hydrogenation coupling reactions, and then through distillation separation, continuously prepare the polyester precursor butylene succinate or modified ester;

[0014] (2) In a kettle reactor, in the presence of a polymerization catalyst, the polyester precursor butylene succinate prepared in step (1) with or without adding a copolymerization modifier, or the polyester precursor butylene succinate modified ester, is successively subjected to a reaction distillation condensation polymerization process including vacuum distillation oligomerization, negative pressure flash evaporation prepolymerization, and vacuum flash evaporation final polymerization to continuously synthesize poly(butylene succinate) or modified copolyesters;

[0015] Among them, the solid acid-supported metal bifunctional catalyst is a catalyst prepared by loading a metal active component with hydrogenation function or a metal active component and a promoter onto a solid acid support with esterification / transesterification function; the acid-metal composite catalyst is a catalyst prepared by uniformly mixing a metal catalyst with hydrogenation function and an acid catalyst with esterification / transesterification function, the metal catalyst includes a bulk metal catalyst or a supported metal catalyst, and the acid catalyst is selected from at least one of solid acids or liquid acids; the options of the solid acid support in the solid acid-supported metal bifunctional catalyst and the solid acid in the acid catalyst both include bulk-type, supported-type or immobilized-type solid acids; the copolymerization modifier is selected from at least one of copolymerization dibasic acids, dibasic acid esters, cyclic anhydrides, polyhydric alcohols, cyclic ethers, hydroxy acids, hydroxy acid esters, lactones or polyhydroxy acids.

[0016] Further, the copolymerization modifier is added in the coupling reaction stage of step (1) and is completely melted or dissolved in C 4 unsaturated diol at the reaction temperature, or added in the oligomerization reaction stage of step (2).

[0017] Further, step (1) specifically includes the following process:

[0018] According to the stoichiometric ratio, the raw materials C 4 unsaturated diol and at least one of C4 diacid and / or its anhydride or / and its ester are heated and melted to prepare a raw material solution with or without the addition of a copolymerization modifier; then, using a fixed bed reactor, the prepared raw material solution is preheated and then transported to a fixed bed reactor filled with solid acid-supported metal bifunctional catalyst particles or solid acid-metal composite catalyst particles that have been pre-reduced and activated, and an esterification-hydrogenation or transesterification-hydrogenation coupling reaction is carried out; then, the coupling reaction product is subjected to gas-liquid separation, and part or all of the liquid-phase material is sent to a flash tower, the light components are continuously removed from the top of the tower, and a material containing the polyester precursor butylene succinate or a modified ester is obtained at the bottom of the tower. The material containing the polyester precursor also contains unesterified completely C 4 saturated oxygen-containing dibasic compounds; or,

[0019] Using a slurry bed reactor, the prepared raw material solution is divided into two streams. One stream is a 2-8 wt% raw material solution fed into a catalyst slurry preparation tank, where it is mixed and stirred evenly with a composition of solid acid-supported metal bifunctional catalyst powder, or solid acid-metal composite catalyst powder, or liquid acid + metal catalyst powder to prepare a catalyst slurry. The other stream is a 92-98 wt% raw material solution that is preheated and then fed into the slurry bed reactor simultaneously with the prepared catalyst slurry, respectively, for esterification-hydrogenation or transesterification-hydrogenation coupling reaction. The coupling reaction product is subjected to gas-liquid separation. The liquid phase material is partially or completely fed into a flash distillation column. Light components are continuously removed from the top of the column, and the filtrate of the bottom material after filtration is a liquid phase material containing the polyester precursor butylene succinate or modified ester. The filter cake is the coupling reaction catalyst and is recycled for preparing the catalyst slurry.

[0020] Further, the gaseous hydrogen separated after the gas-liquid separation of the coupling reaction product is mixed with the supplemented fresh hydrogen, heated to the reaction temperature, and then fed into the reactor for recycling use.

[0021] Further, when using a fixed bed reactor or a slurry bed reactor, when a part of the liquid phase material after the gas-liquid separation of the coupling reaction product is fed into the flash distillation column, the remaining part of the liquid phase material is sent back to the reactor for use as a diluent.

[0022] Further, when the coupling reaction uses a slurry bed reactor, when the liquid phase material after gas-liquid separation is fed into an atmospheric flash distillation column for subsequent treatment, the remaining part of the liquid phase material is filtered after the treatment of the flash distillation column. The filter cake is the solid catalyst, which is collected and recycled for preparing the catalyst slurry.

[0023] Further, the operating conditions of the flash distillation column are: bottom temperature 50-120 °C, top temperature 40-105 °C, and top pressure 90-101 kPa.

[0024] Further, step (2) specifically includes the following process:

[0025] Part of the polymerization catalyst is added to the polyester precursor material obtained in step (1). With or without adding a copolymerization modifier, after mixing evenly, it is fed into an oligomerization reaction kettle for vacuum reaction distillation. After gas-phase removal, an oligomer material is obtained. The remaining polymerization catalyst is added to the oligomer material, and after mixing evenly, it is fed into a prepolymerization reaction kettle for flash pre-polycondensation under negative pressure. After gas-phase removal, a prepolymer product is obtained. The prepolymer product is fed into a final polymerization reaction kettle for flash final polycondensation under vacuum to obtain a final polymerization product, and then pelletized underwater to obtain polybutylene succinate or modified copolyester pellet products. Among them, the dosage of the polymerization catalyst is 0-30% of the total amount of the polymerization catalyst.

[0026] Further, in the above process, the overhead materials of the flash column in step (1) are condensed and mixed with the gaseous materials of synthesizing polyester (including oligomerization, prepolymerization and final polymerization) in step (2), and then sent to the tetrahydrofuran removal column; the by-product tetrahydrofuran is obtained at the top of the tetrahydrofuran removal column, and the bottom materials of the column are sent to the alkanol removal column; the by-product alkanol is obtained at the top of the alkanol removal column, and the bottom materials of the column are sent to the dehydration column again; water is removed at the top of the dehydration column and sent to the wastewater treatment system, and the 1,4-butanediol obtained at the bottom of the column is sent to the raw material preparation tank in step (1) and mixed with C 4 unsaturated diol and recycled as raw materials.

[0027] Further, in step (1), the process conditions of the coupling reaction for preparing the polyester precursor are as follows: the feed space velocity of the raw material solution is 0.05 - 2.00 h -1 , the molar ratio of hydrogen to carbon-carbon unsaturated bond is 5 - 100, the reaction temperature is 60 - 200 °C, the reaction pressure is 1.0 - 8.0 MPa, C 4 dicarboxylic acid and / or its anhydride and / or its ester: C 4 unsaturated diol: copolymerization modifier molar ratio is 1.00:(0.50 - 6.00):(0 - 3.00).

[0028] Further, the feed space velocity of the raw material solution is 0.10 - 1.00 h -1 , the molar ratio of hydrogen to carbon-carbon unsaturated bond is 10 - 80, the reaction temperature is 80 - 180 °C, the reaction pressure is 1.5 - 6.0 MPa;

[0029] Further, the feed space velocity of the liquid raw material is 0.2 - 0.6 h -1 , the molar ratio of hydrogen to carbon-carbon unsaturated bond is 20 - 50, the reaction temperature is 100 - 160 °C, the reaction pressure is 2.0 - 4.5 MPa.

[0030] Further, in step (1), when no copolymerization modifier is added, C 4 dicarboxylic acid and / or its anhydride and / or its ester: C 4 unsaturated diol molar ratio is 1.00:(1.10 - 1.50); preferably, C 4 dicarboxylic acid and / or its anhydride and / or its ester: C 4 unsaturated diol molar ratio is 1.00:(1.15 - 1.35); or,

[0031] when a copolymerization modifier is added, C 4 dicarboxylic acid and / or its anhydride and / or its ester: C 4 unsaturated diol: copolymer dibasic acid and / or dibasic acid ester and / or cyclic anhydride molar ratio 1.00:(1.15 - 4.50):(0.05 - 2.00), or C 4 dicarboxylic acid and / or its anhydride and / or its ester: C 4Unsaturated diol: molar ratio of copolymer polyol and / or cyclic ether is 1.00: (0.55 - 1.45): (0.55 - 0.05), or C 4 Diacid and / or its anhydride and / or its ester: C 4 Unsaturated diol: molar ratio of copolymer hydroxy acid or its ester or lactone or polyhydroxy acid is 1.00: (1.10 - 1.50): (0.05 - 2.00); preferably, C 4 Diacid and / or its anhydride and / or its ester: C 4 Unsaturated diol: molar ratio of copolymer dibasic acid and / or dibasic acid ester and / or cyclic anhydride is 1.00: (1.25 - 2.70): (0.10 - 1.00), or C 4 Diacid and / or its anhydride and / or its ester: C 4 Unsaturated diol: molar ratio of copolymer polyol and / or its cyclic ether is 1.00: (0.90 - 1.25): (0.25 - 0.10), or C 4 Diacid and / or its anhydride and / or its ester: C 4 Unsaturated diol: molar ratio of copolymer hydroxy acid or its ester or lactone or polyhydroxy acid is 1.00: (1.15 - 1.35): (0.10 - 1.00).

[0032] Furthermore, in step (1), in the solid acid-supported metal bifunctional catalyst, the metal active component is one element or a combination thereof selected from Fe, Co, Ni, Cu, Ru, Pd, Pt, or Ag, and the promoter is an oxide of Mg, Ca, Sn, Pb, Y, La, Ce, Sm, or Nd, or an oxide of B, P, Mo, W, or Zn, or a combination of these two types of oxides, wherein: the loading amount of the metal active component is 0.05 - 30 wt%, and the loading amount of the promoter is 0.02 - 20 wt%.

[0033] Preferably, in the solid acid-supported metal bifunctional catalyst, the metal active component is Ni, Ru, Pd, Pt single metal or Ni-Cu, Ni-Co, Ni-Ru, Ni-Pd, Pd-Fe, Pd-Ru, Pt-Co bimetal. The loading amount of the metal active component as a noble metal active component is 0.2 - 2 wt%, or / and the loading amount of the non-noble metal active component is 5.0 - 20 wt%; the promoter is an oxide of Mg, Sn, La, or Ce, or an oxide of Mo, W, or Zn, or a combination of these two types of oxides. The loading amount of the promoter as an alkaline earth or rare earth oxide promoter is 0.1 - 1.0 wt% or the loading amount of other oxide promoters is 1.0 - 10 wt%.

[0034] Furthermore, in step (1), in the acid-metal composite catalyst, the weight ratio of the metal catalyst to the acid catalyst is (10% - 40%): (90% - 60%).

[0035] Further, in step (1), in the acid-metal composite catalyst, the metal catalyst is a bulk or supported metal catalyst, and the acid catalyst is a solid acid or a liquid acid; wherein: the bulk metal catalyst is a modified skeletal metal catalyst or an amorphous alloy catalyst, selected from at least one of Ni-Al-M catalysts, where M includes Mg, Sr, B, Sn, La, Ti, Cr, Mo, W, Mn, Fe, Co, Cu or Zn; preferably, in the Ni-Al-M catalyst, M is selected from at least one of Mo, Co, Cu and Ti;

[0036] The supported metal catalyst includes porous carriers such as AC, CMK, CNT, GPE, SiO 2 , MS, γ-Al 2 O 3 , θ-Al 2 O 3 , MA, SiO 2 -Al 2 O 3 , TiO 2 , ZrO 2 , HM, HHEU, Hβ, HZSM-5, HZSM-11, HZSM-12, HZSM-18, HZSM-22, HZSM-23, HZSM-35, HZSM-48, HMCM-22, HMCM-41, HMCM-48, HMCM-49, HMCM-50, HMCM-56, AlPO 4 -11, SAPO-11, SAPO-34, ZRP-3, S-1, S-2, TS-1, TS-2, SBA-1, SBA-15, ZEO-1, ZEO-2, ZEO-3, KIT-6, SCM-14, SCM-15 or SCM-25, and at least one of them supports a single metal Ni, Ru, Pd, Pt with or without a promoter, or a bimetal of Ni, Ru, Pd, Pt combined with each other or a bimetal or polymetal catalyst combined with at least one of Al, Mg, Sr, Sn, La, Ti, Cr, Mo, W, Mn, Fe, Co, Cu or Zn, and the promoter is one or more of oxides of Mg, Ca, Sn, Pb, Y, La, Ce, Sm, Nd, B, P, Mo, W or Zn; preferably AC, CMK, SiO 2 , MS, γ-Al 2 O 3 , MA, SiO 2 -Al 2 O 3 , TiO 2 , ZrO 2, HM, HHEU, Hβ, HZSM-5, HZSM-11, HZSM-22, HMCM-22, HMCM-41, HMCM-49, SAPO-34, S-1, TS-1, SBA-15, ZEO-1, KIT-6 or SCM-14 supported with or without promoters of single metal Ni, Ru, Pd, or bimetallic Ni-Cu, Ni-Co, Ni-Mo, Ni-Ru, Ni-Pd, Pd-Fe, Pd-Ru, Pt-Co, Ru-Cu, Pd-Cu, Pt-Cu, or polymetallic Ni-Cu-M or Ni-Al-M (M is at least one of Mo, Co, Fe, Cu, Mn, Zn, Ti and Cr) catalysts, wherein the promoter is MgO, La 2 O 3 , CeO 2 , SnO, PbO, MoO 3 , WO 3 or ZnO or their combinations; more preferably AC, SiO 2 , γ-Al 2 O 3 , SiO 2 -Al 2 O 3 , HM, Hβ, HZSM-5, HMCM-22, HMCM-41, SBA-15 or KIT-6 supported with or without promoters of metal Ni, Pd, Ni-Cu, Ni-Ru, Ni-Pd, Ru-Cu, Pd-Cu, Ni-Cu-Mn or Ni-Al-M (M = Mo, Co, Cu and Ti) catalysts, and the promoter is MgO, La 2 O 3 , CeO 2 , MoO 3 , WO 3 or ZnO.

[0037] Furthermore, in step (1), the liquid acid includes alkyl sulfonic acid, aryl sulfonic acid or halogenated organic acid or its salt, and metal halide or metal organic complex; preferably methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, trifluoroacetic acid, trifluoromethanesulfonic acid, trichloromethanesulfonic acid, bis(trifluoromethanesulfonyl)imide, samarium trifluoromethanesulfonate, neodymium trifluoromethanesulfonate, ferric chloride, titanium tetrachloride, antimony pentafluoride, tantalum hexafluoride, dichlorotitanocene, tetrabutyl titanate, titanium butoxide or dibutyltin oxide; more preferably p-toluenesulfonic acid, trifluoroacetic acid, trifluoromethanesulfonic acid, bis(trifluoromethanesulfonyl)imide, samarium trifluoromethanesulfonate, neodymium trifluoromethanesulfonate, tetrabutyl titanate or titanium butoxide.

[0038] Furthermore, in step (1), the bulk solid acid in the solid acid is selected from hydrogen-type zeolite molecular sieve, acidic oxide, solid superacid or hydrogen-type cation exchange resin; wherein:

[0039] The hydrogen-type zeolite molecular sieve is selected from HM (mordenite), HHEU (clinoptilolite), HY, Hβ, HZSM-5, HZSM-11, HZSM-12, HZSM-18, HZSM-22, HZSM-23, HZSM-35, HZSM-48, HMCM-22, HMCM-41, HMCM-48, HMCM-49, HMCM-50 or HMCM-56, preferably HM, Hβ, HZSM-5, HZSM-22, HMCM-22 or HMCM-49;

[0040] The acidic oxide includes γ-Al 2 O 3 , Fe 2 O 3 、MoO 3 , Nb 2 O 5 or H 2 TiO 3 , or an acid, isopolyacid, heteropolyacid or salt thereof of phosphorus, arsenic, selenium, tellurium, antimony, vanadium, molybdenum or tungsten, preferably H 3 PO 4 , H 6 TeO 6 , H 2 WO 4 , Ca(H 2 PO 4 ) 2 、Al(H 2 PO 4 ) 3 、AlPO 4 、Zr(HPO 4 ) 2 、FePO 4 、VPO x , H 3 PW 12 O 40 , H 3 PMo 12 O 40 , H 4 S W 12 O 40 , H 4 SiMo 12 O 40 or Cs 2.5 H 0.5 PW 12 O 40 ;

[0041] The solid superacid is selected from SO 4 2- / ZrO2 and SO 4 2- / TiO 2 and SO 4 2- / Fe 2 O 3 and SO 4 2- / ZrO 2 -La 2 O 3 and SO 4 2- / ZrO 2 -CeO 2 and SO 4 2- / TiO 2 -ZrO 2 and SO 4 2- / ZrO 2 -CeO 2 -Fe 2 O 3 and WO 3 / ZrO 2 or MoO 3 / ZrO 2 and preferably SO 4 2- / ZrO 2 -La 2 O 3 and SO 4 2- / ZrO 2 -CeO 2 -Fe 2 O 3 and WO 3 / ZrO 2 or MoO 3 / ZrO 2 ;

[0042] The hydrogen type cation exchange resin is selected from Amberlyst series A-15, A-16 or A-35, or Amberlite IRC series IRC-50, IRC-76 or IRC-86, or Amberlite FPC series FPC-11, FPC-22 or FPC-3500, or Amberjet series A-1000 or A-1200, or NKC-9, HPK-16, D-001, D-61, D-72, D-113, D-732 or T-62, SB-DH, CR-11, or chlorinated or fluorinated resin; preferably A-15, A-35, IRC-76, A-1200, NKC-9, HPK-16, D-72, T-62 or Nafinon-H.

[0043] Furthermore, in step (1), the supported solid acid in the solid acid comprises a supported solid acid in which an acidic oxide or a solid superacid is supported on a porous carrier, and the supported solid acid has a supported amount of 10 to 60 wt%, preferably 20 to 40 wt%; the supported solid acid in the solid acid is a solid acid obtained by supporting a liquid acid on a porous carrier, and the supported solid acid has a supported amount of 5 to 40 wt%, preferably 10 to 30 wt%; wherein:

[0044] The acidic oxide supported by the supported solid acid includes an oxide, isopoly acid, heteropoly acid or salt thereof of phosphorus, arsenic, selenium, tellurium, antimony, vanadium, molybdenum or tungsten, preferably MoO 3 , Nb 2 O 5 , H 3 PO 4 , H 6 TeO 6 , H 2 WO 4 、Al(H 2 PO 4 ) 3 、AlPO 4 、Zr(HPO 4 ) 2 、VPO x , H 3 PW 12 O 40 , H 3 PMo 12 O 40 , H 4 S W 12 O 40 , H 4 SiMo 12 O 40 or Cs 2.5 H 0.5 PW 12 O 40 ;

[0045] The solid superacid supported by the supported solid acid includes SO 4 2- / ZrO 2 、SO 4 2- / TiO 2 、SO 4 2- / Fe 2 O 3 、SO 4 2- / ZrO 2 -La 2 O 3 、SO 4 2- / ZrO 2 -CeO 2 、SO 4 2- / TiO 2 -ZrO 2 , WO 3 / ZrO 2 or MoO 3 / ZrO 2 ;

[0046] The liquid acid immobilized by the solid-supported solid acid includes a grafted halogenated organic acid or an inorganic halide, a directly impregnated inorganic liquid acid or a metal salt; preferably chloroformic acid, chloroacetic acid, chloropropionic acid, fluoroacetic acid, chlorosulfonic acid or fluorosulfonic acid and salts thereof, chlorides or fluorides of boron, aluminum, gallium, indium, germanium, tin, phosphorus, arsenic, antimony, sulfur, selenium, tellurium, titanium, zirconium, vanadium, chromium, manganese, iron or zinc, or sulfuric acid or phosphoric acid; more preferably monochloroformic acid, monochloroacetic acid, trichloroacetic acid, trifluoroacetic acid, chlorosulfonic acid, trifluoromethanesulfonic acid, samarium trifluoromethanesulfonate, neodymium trifluoromethanesulfonate, boron trifluoride, aluminum trichloride, germanium tetrachloride, phosphorus pentachloride, antimony pentafluoride, titanium tetrachloride, zirconium tetrachloride, ferric chloride, zinc dichloride or phosphoric acid;

[0047] The porous carrier is selected from at least one of activated carbon, mesoporous carbon, carbon nanotubes, graphene, silicon oxide, aluminum oxide, silicon aluminum microspheres, titanium oxide, zirconium oxide or molecular sieves; preferably selected from AC, CMK, amorphous SiO 2 , silica gel, mesoporous silica, amorphous Al 2 O 3 ,γ-Al 2 O 3 ,θ-Al 2 O 3 , pseudo-boehmite, mesoporous alumina (MA), SiO 2 -Al 2 O 3, TiO 2 , ZrO 2 , HM, HHEU, Hβ, HZSM-5, HZSM-22, HMCM-22, HMCM-41, HMCM-48, HMCM-49, HMCM-56, AlPO 4 -11, SAPO-11, SAPO-34, Silicalite-1 (S-1), Silicalite-2 (S-2), TS-1, TS-2, SBA-15, ZEO-1, ZEO-3, KIT-6 or SCM-14, at least one of them.

[0048] Furthermore, in step (2), the polymerization catalyst is selected from titanium trichloride, titanium tetrachloride, tributoxy titanium chloride, tetraethyl titanate, tetraisopropyl titanate, tetrabutyl titanate, tetraiso-octyl titanate, tetra-hydroxyethyl titanate, tetra-hydroxypropyl titanate, tetra-hydroxybutyl titanate, diethylene glycol titanate, dipropylene glycol titanate or dibutylene glycol titanate, preferably tetrabutyl titanate, diethylene glycol titanate or dibutylene glycol titanate; the dosage of the polymerization catalyst is 0.005 - 0.500% of the total mass of the raw materials, preferably 0.010 - 0.100%;

[0049] The oligomerization reaction conditions are: oligomerization reaction temperature 150 - 190 °C, pressure 50 - 100 kPa and material residence time 45 - 120 min, preferably temperature 160 - 180 °C, pressure 70 - 90 kPa and material residence time 60 - 90 min;

[0050] The prepolymerization reaction conditions are: prepolymerization reaction temperature 180 - 220 °C, pressure 5 - 50 kPa and material residence time 30 - 90 min, preferably temperature 190 - 210 °C, pressure 10 - 30 kPa and material residence time 45 - 75 min;

[0051] The final polymerization reaction conditions are: final polymerization reaction temperature 200 - 260 °C, pressure 10 - 200 Pa and material residence time 75 - 180 min, preferably temperature 220 - 240 °C, pressure 50 - 90 Pa and material residence time 90 - 120 min.

[0052] Furthermore, the C 4 unsaturated diol is a C 4 dihydric alcohol containing C = C bond or C≡C bond, preferably butenediol or butynediol.

[0053] Furthermore, the C 4 dicarboxylic acid, anhydride or ester, including C 4Saturated or unsaturated dibasic acids, anhydrides or esters, preferably methylmalonic acid, methylene malonic acid, succinic acid, maleic acid, fumaric acid, acetylenedicarboxylic acid, succinic anhydride, maleic anhydride or their mono-esters or di-esters.

[0054] Further, the copolymerizable dibasic acid, dibasic acid ester or cyclic anhydride includes C 4 dibasic acids, anhydrides and esters other than C 2 ~C 20 aliphatic, aromatic or heterocyclic dibasic acids or cyclic anhydrides or esters; preferably methylsuccinic acid, methylsuccinic anhydride, glutaric acid, glutaric anhydride, adipic acid, adipic anhydride, pimelic acid, suberic acid, azelaic acid, sebacic acid, cyclohexanedicarboxylic acid, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, phthalic acid, phthalic anhydride, naphthalenedicarboxylic acid, biphenyldicarboxylic acid, biphenyldicarboxylic anhydride, furandicarboxylic acid, tetrahydrofurandicarboxylic acid, pyranedicarboxylic acid, tetrahydropyranedicarboxylic acid, pyrroledicarboxylic acid, tetrahydropyrroledicarboxylic acid, pyridinedicarboxylic acid, piperidinedicarboxylic acid or thiophenedicarboxylic acid, or pentenedioic acid, pentenedioic anhydride, itaconic acid, itaconic anhydride, norbornenedicarboxylic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexenedioic acid, hexadienoic acid, heptenedioic acid, octenedioic acid, nonenedioic acid or decenedioic acid, or their mono-esters or di-esters.

[0055] Further, the copolymerizable polyol or cyclic ether includes C 4 aliphatic, aromatic or heterocyclic dihydric or higher alcohols or cyclic ethers other than C 2 ~C 20 unsaturated diols, as well as polyether polyols or polyester polyols; preferably ethylene glycol, 1,3-propanediol, 1,4-butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, glycerol, trimethylolethane, 1,2,6-hexanetriol, trimethylolpropane, erythritol, pentaerythritol, xylitol, sorbitol, mannitol, inositol, 1-phenyl-1,3-propanediol, 2-phenyl-1,3-propanediol, 1-phenyl-1,4-butanediol, m-xylene glycol, p-xylene glycol, 2,6-naphthalenedimethanol, 2,2'-biphenyldimethanol, 4,4'-biphenyldimethanol, 2,5-furandimethanol, 2,6-pyridinedimethanol, diethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polybutylene glycol, polybutylene succinate glycol, polyethylene terephthalate glycol, ethylene oxide, propylene oxide, epichlorohydrin, propylene glycol, tetrahydrofuran, tetrahydrofurfuryl alcohol or tetrahydropyran.

[0056] Further, the copolymerizable hydroxy acid, hydroxy acid ester, lactone or polyhydroxy acid includes C 2 ~C 20Hydroxy acids, hydroxy acid esters or lactones, and polyhydroxy acids; preferably glycolic acid, 2-hydroxypropionic acid (lactic acid), 3-hydroxypropionic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 5-hydroxypentanoic acid, 6-hydroxyhexanoic acid or their methyl esters, or β-propiolactone, γ-butyrolactone, γ-valerolactone, δ-valerolactone or ε-caprolactone, or polyglycolic acid, polylactic acid, poly-3-hydroxypropionic acid, poly-3-hydroxybutyric acid, poly-γ-butyrolactone or polycaprolactone.

[0057] Compared with the prior art, the present invention has the following beneficial effects:

[0058] 1) The present invention firstly proposes to use basic chemical raw material C 4 unsaturated diol and C 4 dicarboxylic acid and / or its anhydride or / and ester as raw materials, and under the condition of adding or not adding a modifier, a two-step integrated innovative process route and continuous production method for preparing precursor succinic acid butanediol ester or modified ester by esterification or transesterification-hydrogenation coupling reaction, and then polycondensing the precursor to synthesize polybutylene succinate or modified copolyester. Compared with the prior art, the first major innovation point and feature of the present invention is that: for the first time, inexpensive and easily available basic raw materials C 4 unsaturated diols (butynediol, butenediol) are used as alcohol raw materials for synthesizing polyesters, and C 4 unsaturated dicarboxylic acids, acid anhydrides or esters (maleic anhydride, maleic acid and fumaric acid and their esters) or C 4 saturated dicarboxylic acids, acid anhydrides or esters (succinic anhydride, succinic acid and their esters) are used as acid raw materials for synthesizing polyesters, and through the coupling reaction process, the two types of raw materials simultaneously carry out hydrogen saturation of C=C or / and C≡C bonds and esterification or transesterification reactions in the same reactor to prepare polyester precursors, eliminating the cumbersome process of separately producing alcohol monomer 1,4-butanediol and acid monomer succinic anhydride or acid or ester in the prior art, greatly shortening the process flow, saving equipment investment, improving raw material utilization rate and reducing production costs.

[0059] 2) The present invention for the first time adopts an esterification or transesterification-hydrogenation fixed bed or slurry bed coupling reaction process combined with a reaction product distillation separation process to continuously prepare a polyester precursor, and adopts a reactive distillation kettle polymerization process of vacuum distillation oligomerization-negative pressure flash pre-polymerization-vacuum flash final polymerization to continuously synthesize polyester. Compared with the prior art, the second major innovation and feature of the present invention lies in that: due to the adoption of a brand-new synthesis process, the esterification and polycondensation reactions are milder and more efficient, greatly reducing the etherification side reaction of alcohol monomers and the generation amount of wastewater, improving the effective utilization rate of raw materials and the polyester yield; due to the addition of a flash evaporation process for coupling reaction products and a vacuum distillation oligomerization process, low-boiling small molecules such as water or alkanol generated in the esterification or transesterification and oligomerization stages are timely removed from the system, while the excessive alcohol monomers are retained until the pre-polycondensation stage. On the one hand, the esterification or transesterification reaction equilibrium is broken, so that the acid monomers that are not completely esterified in the coupling reaction are completely esterified and the precursor is converted into an oligomer, avoiding the residue of acid monomers and polymer terminal carboxyl groups, greatly reducing the acid value and molecular weight distribution of the polyester. On the other hand, it prevents or slows down the hydrolysis failure rate of the polymerization catalyst, improves the polymerization reaction efficiency and the degree of polymerization, reduces the amount of polymerization catalyst used, and thus reduces the metal content in the polyester product; in the polycondensation stage, a high-vacuum flash evaporation process is adopted to instantaneously remove the catalyst, excessive alcohol monomers and small molecules generated in the polycondensation reaction from the system when the coupling reaction uses a liquid acid catalyst, avoiding the problems that the liquid acid catalyst and low-molecular-weight substances remain in the polyester product, resulting in poor color and luster of the polyester, high acid value and melt index, and short service life.

[0060] 3) The present invention uses a solid acid-supported metal bifunctional catalyst or an acid-metal composite catalyst to achieve the continuous preparation of a polyester precursor, butylene succinate or a modified ester, from C 4 unsaturated diols and C 4 dianhydride or acid or ester and a copolymerization modifier (added or not added) through an esterification / transesterification-hydrogenation coupling reaction, and uses an efficient polymerization catalyst to complete the polycondensation of the precursor to synthesize polyester, greatly shortening the process flow and reducing the manufacturing cost of polyester.

[0061] 4) The present invention can not only prepare the polyester precursor butylene succinate through the one-step esterification / transesterification-hydrogenation coupling reaction of basic raw materials, and then synthesize poly(butylene succinate) (PBS) through polycondensation, but also prepare the modified copolyester precursor of butylene succinate through the coupling reaction by adding a copolymerization modifier with a lower melting point and viscosity to the raw materials, and then prepare the modified copoly(butylene succinate) (PBSX) through polycondensation. It can also prepare PBSX or block copolymers through the co-polycondensation of a copolymerization modifier with a higher melting point and viscosity and the precursor butylene succinate at the oligomerization stage. It can be seen that the process technical solution of the present invention is flexible, and multiple series of poly(butylene succinate) products can be produced on the same production line. By adding copolymer dibasic acids such as adipic acid, terephthalic acid or 2,5-furandicarboxylic acid, etc., PBSA, PBST or PBSF and other series of products can be produced. By adding copolymer diols such as ethylene glycol, p-xylene glycol or 2,5-furandimethanol, etc., PBES, PBCS or PBFS and other series of products can be produced. By adding modifiers such as polyols or hydroxy acids such as pentaerythritol, trimethylolpropane, glycolic acid or lactic acid, etc., SPBS, TPBS, GPBS or LPBS and other series of PBS modified products can be produced. And by adding polyethylene glycol, polybutylene glycol, polyethylene terephthalate glycol, polyglycolic acid or polylactic acid, etc. at the oligomerization stage, corresponding block copolymers such as PBS-co-PEG, PBS-co-PTMG, PBS-co-PET, PBS-co-PGA, PBS-co-PLA can be produced to meet various market demands. Detailed Embodiments

[0062] The following combines specific embodiments to further elaborate on the present invention. It should be noted that the embodiments described in this part are only partial embodiments of the present invention, not all of them. In view of this, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present invention.

[0063] Symbol Explanation:

[0064] SAA is succinic anhydride, DMM is dimethyl maleate, DMF is dimethyl fumarate, DMS is dimethyl succinate, BA is butynedioic acid, DMAD is dimethyl butynedioate; PTA is terephthalic acid, DMT is dimethyl terephthalate, DMA is dimethyl adipate, FDCA is 2,5-furandicarboxylic acid, FDME is dimethyl 2,5-furandicarboxylate, CHDM is 1,4-cyclohexanedimethanol, TMP is trimethylolpropane, THME is pentaerythritol; PTMG is polybutylene glycol, PET is polyethylene terephthalate glycol, PLA is polylactic acid; BS is butylene succinate (monoester or / and diester).

[0065] Calculation Explanation:

[0066]

[0067] Total feed weight = C 4 Unsaturated diol weight + C 4 Diacid / anhydride / alkyl ester weight + copolymerization modifier weight

[0068] Examples 1 - 15: Using butanediol and C 4 Synthesizing polybutylene succinate (PBS) using diacid and its anhydride or ester as raw materials

[0069] Examples 1 - 6

[0070] Using butanediol and C 4 Synthesizing polybutylene succinate (PBS) using diacid and its anhydride or ester as raw materials. The coupling reaction uses a fixed - bed reactor, and specifically includes the following steps:

[0071] (1) Mix butanediol and maleic anhydride according to the metering ratio in Table 1 - 1 to prepare a raw material solution, and feed it into the fixed - bed reactor in co - current with hydrogen from top to bottom for esterification - hydrogenation coupling reaction. The fixed - bed reactor is filled with a bifunctional catalyst or a solid acid - supported metal composite catalyst that has been pre - reduced and activated;

[0072] (2) Carry out gas - liquid separation on the material after the reaction in step (1). The gaseous hydrogen is sent back to the reactor for recycling, 15% of the liquid - phase material is sent back to the reactor as a diluent, and the remaining 85% is sent into an atmospheric flash distillation column. The light components removed from the top of the column are sent into an alcohol / ether recovery system, and the material containing BDO and the polyester precursor BS is obtained at the bottom of the column;

[0073] (3) After adding 20% of the polymerization catalyst tetrabutyl titanate to the material containing the polyester precursor obtained in step (2), send it into an oligomerization reaction kettle for vacuum reactive distillation. The gaseous phase removes a small amount of water, THF, and excess BDO generated by the oligomerization reaction, and the oligomer is obtained at the bottom of the column;

[0074] (4) Add the remaining 80% of the polymerization catalyst to the oligomer obtained in step (3), mix evenly, and then send it into a prepolymerization reaction kettle for prepolycondensation reaction under negative pressure to obtain a prepolymer;

[0075] (5) Send the prepolymer obtained in step (4) into a final polycondensation reaction kettle for final polycondensation reaction under vacuum to obtain polybutylene succinate (PBS), and then obtain PBS polyester pellet products through underwater pelletizing.

[0076] During the above process, the overhead material of the flash distillation column and the gaseous phase materials of the polycondensation reactions (oligomerization, prepolymerization, and final polycondensation) are condensed and mixed, then sent into the alcohol / ether recovery system. The separated and recovered THF is used as a by - product, the separated and recovered BDO is sent into the raw material preparation tank for recycling, and the removed water is sent into the wastewater treatment system.

[0077] Examples 7 - 15

[0078] Butanediol and C 4 dicarboxylic acid, its anhydride or ester are used as raw materials to synthesize polyester PBS. The coupling reaction is carried out in a slurry bed reactor, and the specific steps are as follows:

[0079] (1) According to the metering ratio in Table 1 - 1, mix butanediol, the corresponding C 4 dicarboxylic acid or anhydride or ester, liquid acid catalyst and pre - reduced and activated metal catalyst powder to prepare a raw material slurry, and feed it into the slurry bed reactor in co - current with hydrogen from top to bottom for esterification / transesterification - hydrogenation coupling reaction;

[0080] (2) Separate the gas - liquid of the material after the reaction in step (1). The gaseous hydrogen is sent back to the reactor for recycling. 20% of the liquid phase material is sent back to the reactor as a diluent, and the remaining 80% is sent into a filter. The filter cake is recovered and recycled as a hydrogenation catalyst. The filtrate is sent into an atmospheric flash tower. The light components removed from the top of the tower are sent into an alcohol / ether recovery system, and the material obtained at the bottom of the tower contains a liquid acid catalyst, BDO, succinic acid or its dimethyl ester, and a polyester precursor;

[0081] (3) After adding 20% of the polymerization catalyst tetrabutyl titanate to the material containing the polyester precursor obtained in step (2), send it into an oligomerization reaction kettle for vacuum reactive distillation. The gas phase removes a small amount of water and THF generated by the oligomerization reaction, as well as the liquid acid catalyst (or decomposed liquid acid catalyst) and excessive BDO. The oligomer is obtained at the bottom of the tower;

[0082] (4) Add the remaining 80% of the polymerization catalyst to the oligomer obtained in step (3), mix evenly and then send it into a prepolymerization reaction kettle for pre - polycondensation reaction under negative pressure to obtain a prepolymer;

[0083] (5) Send the prepolymer obtained in step (4) into a final polycondensation reaction kettle for final polycondensation reaction under vacuum to obtain polybutylene succinate (PBS), and then obtain PBS polyester pellet products through underwater pelletizing;

[0084] In the above process, the overhead material of the flash tower and the condensed gas - phase materials of the polycondensation reaction (oligomerization, prepolymerization and final polycondensation) are mixed and sent into the alcohol / ether recovery system. The separated and recovered THF or THF and methanol are used as by - products. The separated and recovered liquid acid and BDO are sent into the raw material preparation tank for recycling, and the removed water is sent into the wastewater treatment system.

[0085] In Examples 1 - 15, the catalysts, process conditions and reaction results for the esterification / transesterification - hydrogenation coupling reaction of butanediol and the corresponding C 4 dicarboxylic acid or anhydride or ester to prepare the polyester PBS precursor butylene succinate are shown in Table 1 - 1. Among them, the C in Example 15 4The raw materials of diacid, anhydride or ester are a mixed raw material of maleic anhydride and SAA, and the molar ratio of the two is 1:1. The reaction process conditions, polyester effective yield and performance indexes of the precursors in Examples 1 to 15 for synthesizing polyester PBS by polycondensation are shown in Tables 1-2 and 1-3.

[0086] Table 1-1 Catalysts, process conditions and reaction results for preparing polyester PBS precursors by coupling reaction in Examples 1 to 15

[0087]

[0088] As shown in Table 1-1, all the solid acid-supported metal bifunctional catalysts or composite catalysts composed of acid + metal alloy or supported metal in Examples 1 to 15, under the coupling reaction conditions of temperature 110 - 200 °C, hydrogen pressure 2.0 - 6.0 MPa, feed space velocity 0.1 - 0.6 h -1 ⁻¹, molar ratio of hydrogen to C=C double bond 20 - 80, and molar ratio of diol to diacid, anhydride or dimethyl ester 1.10 - 1.50:1.00, the C=C double bonds of butenediol and maleic anhydride or fumaric acid or their dimethyl esters can be completely hydrogenated and saturated, and the acid anhydride (maleic anhydride or succinic anhydride) and diol can all undergo ring-opening esterification reaction by 100% to generate polyester precursor BS. However, the esterification or transesterification reaction between diacid or dimethyl ester and diol is not complete under the pressurized reaction conditions due to the chemical equilibrium, and its molar conversion rate is 85.2 - 90.5%, and there is still 9.5 - 14.8% of succinic acid (SAA) or dimethyl succinate (DMS) remaining.

[0089] Table 1-2 Process conditions and yields for synthesizing polyester PBS by polycondensation of precursor BS

[0090]

[0091]

[0092] Table 1-3 Performance indexes for synthesizing polyester PBS by polycondensation of precursor BS

[0093] Example Metal content (ppm) Colorimetric L value Melt index (g / 10min) Acid value (mol / t) <![CDATA[Mw(10 4 )]]> Tensile strength (MPa) Example 1 96 85 19 19 18.9 48 Example 2 48 87 28 26 17.2 44 Example 3 94 83 20 21 18.3 45 Example 4 65 86 22 23 17.8 47 Example 5 53 89 25 25 17.5 43 Example 6 83 87 15 24 18.4 46 Example 7 32 90 18 28 16.8 43 Example 8 60 89 17 25 17.3 45 Example 9 29 91 13 29 17.2 45 Example 10 31 90 32 33 15.5 42 Example 11 45 90 30 36 15.2 41 Example 12 51 90 22 18 17.2 44 Example 13 86 88 23 20 17.0 43 Example 14 89 85 26 24 18.2 46 Example 15 61 88 25 25 17.6 45

[0094] As shown in Table 1-2 and Table 1-3, in Examples 1 to 15, the coupling reaction product (precursor BS or a mixture of BS and residual SAA / DMS and 1,4-butanediol) was subjected to a condensation polymerization process of vacuum distillation oligomerization (temperature 160 - 180 °C, pressure 70 - 90 kPa, and 45 - 120 min), negative pressure flash pre-polymerization (temperature 190 - 210 °C, pressure 10 - 30 kPa, and 45 - 75 min), and vacuum flash final polymerization (temperature 220 - 240 °C, pressure 50 - 90 Pa, and 90 - 120 min), and the effective yield of polyester PBS obtained was 71.93 - 91.52 wt%, among which the effective yield of PBS starting from acid anhydride or the effective utilization rate of raw materials was 86.08 - 91.52 wt%; the obtained PBS polyester products had excellent performance indicators, low metal content (29 - 98 ppm), good color (chromaticity L value 83 - 91), low melt index (13 - 32 g / 10 min), low acid value (18 - 36 mol / t), high weight-average molecular weight (152,000 - 189,000), and high tensile strength (41 - 48 MPa).

[0095] Examples 16 to 21

[0096] Butynediol and C 4 Diacid and its anhydride or ester were used as raw materials to synthesize polyester PBS. The coupling reaction used a fixed-bed reactor, and its process flow was to mix butynediol and C 4 Diacid or anhydride according to the stoichiometric ratio in Table 2-1 to prepare a raw material solution, and feed it into the fixed-bed reactor in parallel with hydrogen from top to bottom for esterification-hydrogenation coupling reaction. The fixed bed was filled with a bifunctional catalyst or a solid acid-supported metal composite catalyst that had been pre-reduced and activated. The polymerization catalyst used cyclic dibutylene glycol titanate, and the rest of the operation process was the same as in Example 1.

[0097] Example 22

[0098] The process flow for synthesizing polyester PBS is as follows:

[0099] (1) Mix butynediol, dimethyl succinate, and 300 ppm of the transesterification liquid acid catalyst tetrabutyl titanate according to the stoichiometric ratio in Table 2-1 to prepare a raw material solution, and feed it into the fixed-bed reactor in countercurrent with hydrogen from top to bottom for transesterification-hydrogenation coupling reaction. The fixed-bed reactor was filled with a pre-reduced and activated supported metal catalyst 0.5 wt% Pd - 5 wt% Ni / γ-Al 2 O 3 ;

[0100] (2) Separate the material after the reaction in step (1) into gas and liquid. The gaseous hydrogen is sent back to the reactor for recycling, 15% of the liquid-phase material is sent back to the reactor as a diluent, and the remaining 85% is sent to an atmospheric flash column. The light components removed from the top of the column are sent to an alcohol / ether recovery system, and the material obtained at the bottom of the column contains tetrabutyl titanate, BDO, dimethyl succinate that has not been completely transesterified, and a polyester precursor.

[0101] (3) Send the material containing the polyester precursor obtained at the bottom of the column in step (2) to an oligomerization reaction kettle for vacuum reactive distillation. The gas phase removes a small amount of water, THF, and excess BDO generated by the oligomerization reaction, and the oligomer is obtained at the bottom of the column.

[0102] (4) Add all of the polymerization catalyst, cyclic dibutylene glycol titanate, to the oligomer obtained in step (3). After mixing evenly, send it to a prepolymerization reaction kettle and carry out a prepolycondensation reaction under negative pressure to obtain a prepolymer product.

[0103] (5) Send the prepolymer product obtained in step (4) to a final polycondensation reaction kettle and carry out a final polycondensation reaction under vacuum to obtain poly(butylene succinate) (PBS), and then obtain PBS polyester pellet products through underwater pelletization.

[0104] In the above process, the material at the top of the flash column and the condensed gas-phase materials from the polycondensation reactions (oligomerization, prepolymerization, and final polycondensation) are mixed and sent to an alcohol / ether recovery system. The separated and recovered THF and methanol are used as by-products, the separated and recovered BDO is sent to the raw material preparation tank for recycling, and the removed water is sent to the wastewater treatment system.

[0105] Examples 23 - 25

[0106] Using butynediol and C 4 dioic acid and its anhydride or ester as raw materials to synthesize polyester PBS, the coupling reaction uses a fixed-bed reactor. The process flow is to mix and prepare a raw material solution of butynediol and C 4 dioic acid or anhydride according to the metering ratio in Table 2-1, and feed it into the fixed-bed reactor in a co-current manner with hydrogen from top to bottom for an esterification-hydrogenation coupling reaction. The fixed-bed reactor is filled with a bifunctional catalyst or a solid acid-supported metal composite catalyst that has been pre-reduced and activated in advance; the polymerization catalyst uses cyclic dibutylene glycol titanate, and the rest of the operation process is the same as that in Example 1.

[0107] Examples 26 - 30

[0108] Using butynediol and C 4 dioic acid and its anhydride or ester as raw materials to synthesize polyester PBS, the coupling reaction uses a slurry-bed reactor. The process flow is: according to the metering ratio in Table 2-1, mix butynediol and C 4A raw material slurry is prepared by mixing a diacid or ester, a liquid acid catalyst, and a pre-reduced and activated metal catalyst powder. The slurry is fed into a slurry bed reactor from bottom to top in co-current with hydrogen for an esterification / transesterification-hydrogenation coupling reaction. The polymerization catalyst used is dibutylene glycol cyclic titanate, and the rest of the operation process is the same as that in Example 7, but the addition method and amount of the polymerization catalyst in Examples 29 and 30 are the same as those in Example 22.

[0109] Examples 16 - 30 Butynediol and the corresponding C 4 The catalysts, process conditions, and reaction results for the esterification / transesterification-hydrogenation coupling reaction of butynediol with the corresponding diacid or anhydride or ester to prepare the polyester PBS precursor BS are shown in Table 2-1. Among them, the C 4 diacid or anhydride or ester raw material in Example 30 is a mixed raw material composed of maleic acid and DMM, and the molar ratio of the two is 1:1. The reaction process conditions, polyester effective yield, and performance indicators for the polycondensation of the precursors in Examples 16 - 30 to synthesize the polyester PBS are shown in Tables 2-2 and 2-3.

[0110] Table 2-1 Catalysts, Process Conditions, and Reaction Results for the Preparation of Polyester PBS Precursors by Coupling Reactions in Examples 16 - 30

[0111]

[0112]

[0113] Table 2-2 Process Conditions and Yields for the Polycondensation of Polyester Precursors in Examples 16 - 30 to Synthesize Polyester PBS

[0114]

[0115] Table 2-3 Performance Indicators for the Polycondensation of Polyester Precursors in Examples 16 - 30 to Synthesize Polyester PBS

[0116] Example Metal content (ppm) Colorimetric L value Melt index (g / 10min) Acid value (mol / t) <![CDATA[Mw(10 4 )]]> Tensile strength (MPa) Example 16 58 88 21 26 18.2 45 Example 17 84 85 16 20 19.2 49 Example 18 62 88 22 25 18.5 47 Example 19 86 83 15 21 19.0 48 Example 20 84 83 13 22 18.9 46 Example 21 32 91 32 29 16.5 44 Example 22 96 87 26 16 15.2 42 Example 23 42 90 28 25 17.1 46 Example 24 45 89 30 32 14.5 40 Example 25 55 88 29 31 14.8 41 Example 26 85 87 22 18 16.7 46 Example 27 88 88 24 19 16.4 46 Example 28 64 87 22 30 14.2 39 Example 29 95 86 20 22 16.3 45 Example 30 97 85 19 27 15.5 43

[0117] As shown in Table 2-1, in Examples 16 - 30, during the process of the esterification / transesterification-hydrogenation coupling reaction of butynediol with the corresponding diacid or anhydride or ester to prepare the polyester PBS precursor BS, all the solid acid-supported metal bifunctional catalysts or composite catalysts composed of an acid and a metal alloy or a supported metal are at a temperature of 120 - 180 °C, a hydrogen pressure of 3.5 - 5.5 MPa, and a feed space velocity of 0.1 - 0.5 h 4 -1. -1Under the coupling reaction conditions with a molar ratio of hydrogen to C=C double bond of 15 - 50 and a molar ratio of diol to diacid or anhydride or dimethyl ester of 1.10 - 1.53:1.00, both the C=C and / or C≡C bonds of butynediol and maleic anhydride or butene / alkynedioic acid or its dimethyl ester can be completely hydrogenated and saturated, and the acid anhydride (maleic anhydride or succinic anhydride) and diol can undergo 100% ring-opening esterification reaction to form the polyester precursor BS. However, for the esterification or transesterification reaction between diacid or dimethyl ester and diol, due to the chemical equilibrium, it is incomplete under the pressurized reaction conditions, and its conversion rate is 80.2 - 91.2 mol%, with 8.8 - 19.8 mol% of SAA or DMS remaining.

[0118] As shown in Tables 2 - 2 and 2 - 3, in Examples 16 - 30, the coupling reaction product undergoes a condensation polymerization process of vacuum distillation oligomerization (temperature 160 - 180 °C, pressure 60 - 90 kPa, and 60 - 120 min), negative pressure flash pre-polymerization (temperature 190 - 220 °C, pressure 5 - 35 kPa, and 30 - 75 min), and vacuum flash final polymerization (temperature 220 - 250 °C, pressure 30 - 90 Pa, and 75 - 150 min) to obtain an effective yield of polyester PBS of 71.90 - 89.97 wt%. Among them, the effective yield or raw material utilization rate of PBS with acid anhydride as the starting material is 87.10 - 89.97 wt%; the obtained PBS polyester products have excellent performance indicators, low metal content (32 - 86 ppm), good color (chromaticity L value 83 - 91), low melt index (13 - 32 g / 10 min), low acid value (16 - 32 mol / t), high weight average molecular weight (142,000 - 192,000), and high tensile strength (39 - 49 MPa).

[0119] Examples 31 - 35

[0120] Butenediol and C 4 Diacid and anhydride or ester and a copolymerization modifier are used to synthesize polyester PBSX. Among them, a fixed-bed reactor is used for the coupling reaction, and the copolymerization modifier is added in the oligomerization reaction stage. The specific process is as follows:

[0121] According to the metering ratio in Table 3 - 1, butenediol and maleic anhydride are mixed to prepare a raw material solution, which is fed into the fixed-bed reactor in co-current with hydrogen from top to bottom for esterification-hydrogenation coupling reaction. The fixed-bed reactor is filled with a γ-Al 2 O 3 supported nickel-based amorphous alloy bifunctional catalyst; then the reaction mixture is subjected to gas-liquid separation, the gaseous hydrogen is recycled back to the reactor, 18% of the liquid phase material is recycled back to the reactor as a diluent, and the remaining 82% is fed into an atmospheric flash distillation column. The light components removed from the top of the column are sent to the alcohol / ether recovery system, and the material containing BDO and polyester precursor is obtained at the bottom of the column;

[0122] After adding a copolymerization modifier and 25% of the polymerization catalyst tetrabutyl titanate to the polyester precursor material, it is sent to an oligomerization reaction kettle for vacuum reactive distillation. Among them, the modifiers in Examples 33 to 35 are PTMG, PET, and PLA respectively, and their feeding molar ratios are measured based on their repeating structural units; a small amount of water, THF, and excessive BDO generated by the oligomerization reaction are removed by gas phase, and an oligomer is obtained at the bottom of the tower; the remaining 75% of the polymerization catalyst is added to the oligomer, and after mixing evenly, it is sent to a prepolymerization reaction kettle for prepolycondensation reaction under negative pressure to obtain a prepolymer product; the prepolymer product is sent to a final polymerization reaction kettle for final polycondensation reaction under vacuum to obtain a butanediol succinate copolymer modified ester (PBSX), and then PBSX polyester pellet products are obtained through underwater pelletizing; the overhead material of the flash tower is condensed and mixed with the gas phase materials of the polycondensation reaction (oligomerization, prepolymerization, and final polymerization), and sent to an alcohol / ether recovery system. The separated and recovered THF is used as a by-product, the separated and recovered BDO is sent to the raw material preparation tank for recycling, and the removed water is sent to the wastewater treatment system.

[0123] Examples 36 - 45

[0124] Butanediol and C 4 Diacid and its anhydride or ester and a copolymerization modifier are used to synthesize polyester PBSX. Among them, a slurry bed reactor is used for the coupling reaction, and the copolymerization modifier is added in the coupling reaction stage. According to the metering ratio in Table 3 - 1, butanediol is mixed with the corresponding C 4 Diacid or anhydride or ester, copolymerization modifier, liquid acid catalyst, and pre-reduced and activated metal catalyst powder are mixed to prepare a raw material slurry, which is fed into the slurry bed reactor from bottom to top in parallel with hydrogen for esterification / transesterification - hydrogenation coupling reaction. Among them, the C 4 Diacid and its anhydride or ester raw material in Example 45 is a mixed raw material composed of SAA and succinic acid, and the molar ratio of the two is 1:1; the remaining operation processes and polymerization catalysts in Examples 36 to 45 are the same as those in Example 7, but the addition methods of the polymerization catalysts in Examples 39, 42, and 43 are the same as those in Example 22.

[0125] In Examples 31 - 45, the catalysts, process conditions, and reaction results of the esterification / transesterification - hydrogenation coupling reaction of butanediol with the corresponding C 4 Diacid or anhydride or ester and copolymerization modifier for preparing the precursor of polyester PBSX, butanediol succinate modified ester, are shown in Table 3 - 1. The reaction process conditions, polyester effective yield, and performance indicators of the precursor polycondensation synthesis of copolymer polyester PBSX in Examples 31 - 45 are shown in Tables 3 - 2 and 3 - 3.

[0126] Table 3 - 1 Catalysts, Process Conditions, and Reaction Results of the Coupling Reaction for Preparing the Precursor of Polyester PBSX in Examples 31 - 45 (the molar ratios of the modifier polymers in Examples 33 - 35 are based on their repeating structural units)

[0127]

[0128]

[0129] Table 3-2 Process conditions and yields for the synthesis of polyester PBSX by polycondensation of precursors in Examples 31-45

[0130]

[0131] Table 3-3 Product performance indicators for the synthesis of polyester PBSX by polycondensation of precursors in Examples 31-45

[0132]

[0133]

[0134] As shown in Table 3-1, in the esterification / transesterification-hydrogenation coupling reaction of butanediol with the corresponding C 4 dicarboxylic acid or anhydride or ester and the copolymerization modifier in Examples 31-45, all solid acid-supported metal bifunctional catalysts and liquid acid-supported bimetallic composite catalysts, under the coupling reaction conditions of a temperature of 140-160 °C, a feed weight hourly space velocity of 0.1-0.3 h -1 , a hydrogen pressure of 3.5-4.5 MPa, a molar ratio of hydrogen to unsaturated bonds of 30-50, and a feed molar ratio of diol:dicarboxylic acid or anhydride or ester:modifier = 1.15-1.50:1.00:0.05-0.25, can completely hydrogenate and saturate the C=C bonds of butanediol, maleic anhydride or maleic acid and dimethyl ester, and the copolymerization modifier, and can also cause 100% ring-opening esterification of the dianhydride and diol to form the PBSX precursor BS modified ester. However, due to the chemical equilibrium existing in the esterification of the dicarboxylic acid and diol or the transesterification of the dimethyl ester and diol, the esterification or transesterification is incomplete under the pressurized conditions of the coupling reaction, and the conversion rate of the dicarboxylic acid or dimethyl ester is 84.2-90.8 mol%, and the residual rate of the dicarboxylic acid or dimethyl ester is 9.2-15.8 mol%.

[0135] As shown in Tables 3-2 and 3-3, in Examples 31 to 45, the coupled reaction product was subjected to a polycondensation process including vacuum distillation oligomerization (temperature 150 - 180 °C, pressure 50 - 90 kPa, and 75 - 120 min), negative pressure flash pre-polymerization (temperature 180 - 210 °C, pressure 5 - 45 kPa, and 30 - 90 min), and vacuum flash final polymerization (temperature 220 - 260 °C, pressure 50 - 120 Pa, and 100 - 135 min), to obtain a polyester PBS with an effective yield of 72.80 - 89.62 wt%, among which the effective yield of PBS starting from acid anhydride or the effective utilization rate of raw materials was 85.39 - 89.62 wt%; the polyester PBS products had excellent performance indicators, low metal content (67 - 105 ppm), good color (chromaticity L value 80 - 89), low melt index (15 - 32 g / 10 min), low acid value (17 - 32 mol / t), high weight average molecular weight (138,000 - 255,000), and high tensile strength (28 - 49 MPa).

[0136] Examples 46 - 49

[0137] Butynediol and C 4 dicarboxylic acid and its anhydride or ester and a copolymerization modifier were used to synthesize polyester PBSX. Among them, a fixed bed reactor was used for the coupling reaction, and the copolymerization modifier was added in the oligomerization reaction stage. The specific process is as follows:

[0138] According to the metering ratio in Table 4-1, butynediol and succinic anhydride were mixed to prepare a raw material solution, which was fed into a fixed bed reactor filled with a bifunctional catalyst pre-reduced and activated from top to bottom in parallel flow with hydrogen for an esterification-hydrogenation coupling reaction; the remaining operation processes and polymerization catalysts were the same as those in Example 31; the modifier in Example 49 was PLA, and its feeding molar ratio was measured based on its repeating structural unit.

[0139] Examples 50 - 51

[0140] Butynediol and C 4 dicarboxylic acid and its anhydride or ester and a copolymerization modifier were used to synthesize polyester PBSX. Among them, a fixed bed reactor was used for the coupling reaction, and the copolymerization modifier was added in the coupling reaction stage. The specific process is as follows:

[0141] According to the metering ratio in Table 4-1, butynediol and the corresponding C 4 dicarboxylic acid or anhydride and the copolymerization modifier were mixed to prepare a raw material solution, which was fed into a fixed bed reactor filled with a bifunctional catalyst pre-reduced and activated or a solid acid-supported metal composite catalyst from top to bottom in parallel flow with hydrogen for an esterification-hydrogenation coupling reaction; the remaining operation processes and polymerization catalysts were the same as those in Example 1.

[0142] Example 52

[0143] Butynediol and C4 Diacids and anhydrides or esters and copolymerization modifiers are used to synthesize polyester PBSX. Among them, the coupling reaction uses a slurry bed reactor, and the copolymerization modifier is added in the coupling reaction stage. The specific process is as follows:

[0144] According to the metering ratio in Table 4-1, butynediol is mixed with the corresponding C 4 Diacids or esters, copolymerization modifiers, liquid acid catalysts, and pre-reduced and activated metal catalyst powders are mixed to prepare a raw material slurry, which is fed into the slurry bed reactor in parallel with hydrogen from top to bottom for esterification / transesterification-hydrogenation coupling reaction; the remaining operation processes and polymerization catalysts are the same as those in Example 7, and in this example, the addition method of the polymerization catalyst is the same as that in Example 22.

[0145] Examples 53 - 55

[0146] Butynediol and C 4 Diacids and anhydrides or esters and copolymerization modifiers are used to synthesize polyester PBSX. Among them, the coupling reaction uses a fixed bed reactor, and the copolymerization modifier is added in the coupling reaction stage. The specific process is as follows:

[0147] According to the metering ratio in Table 4-1, butynediol is mixed with the corresponding C 4 Diacid anhydrides and copolymerization modifiers are mixed to prepare a raw material solution, which is fed into a fixed bed reactor filled with pre-reduced and activated bifunctional catalysts or solid acid-supported metal composite catalysts in parallel with hydrogen from top to bottom for esterification-hydrogenation coupling reaction; the remaining operation processes and polymerization catalysts are the same as those in Example 1.

[0148] Examples 56 - 59

[0149] Butynediol and C 4 Diacids and anhydrides or esters and copolymerization modifiers are used to synthesize polyester PBSX. Among them, the coupling reaction uses a slurry bed reactor, and the copolymerization modifier is added in the coupling reaction stage. The specific process is as follows:

[0150] According to the metering ratio in Table 4-1, butynediol is mixed with the corresponding C 4 Diacids or esters, copolymerization modifiers, liquid acid catalysts, and pre-reduced and activated metal catalyst powders are mixed to prepare a raw material slurry, which is fed into the slurry bed reactor in parallel with hydrogen from top to bottom for esterification / transesterification-hydrogenation coupling reaction; the remaining operation processes and polymerization catalysts are the same as those in Example 7, and in Example 59, the addition method of the polymerization catalyst is the same as that in Example 22.

[0151] Example 60

[0152] Unsaturated diols and C 4 Diacids and anhydrides or esters and copolymerization modifiers are used to synthesize polyester PBSX. Among them, the coupling reaction uses a fixed bed reactor, and the copolymerization modifier is added in the coupling reaction stage. The specific process is as follows:

[0153] The mixture of butynediol and butenediol with a molar ratio of 1.0:1.0 was used as the unsaturated diol raw material according to the metering ratio in Table 4-1, and was mixed with succinic anhydride and the copolymerization modifier glutaric anhydride to prepare a raw material solution. Then, it was fed into a fixed-bed reactor filled with 0.5 wt% Pd-5.0 wt% Cu / γ-Al 2 O 3 which had been pre-reduced and activated, in a downward co-current manner with hydrogen to carry out the esterification-hydrogenation coupling reaction; the remaining operation processes and polymerization catalysts were the same as those in Example 1.

[0154] Examples 46 to 60 The butynediol and the corresponding C 4 dicarboxylic acid or anhydride or ester and the copolymerization modifier were used to carry out the esterification / transesterification-hydrogenation coupling reaction to prepare the polyester PBSX precursor, the modified ester of butanediol succinate. The catalysts, process conditions and reaction results are shown in Table 4-1. The reaction process conditions, polyester effective yield and performance indexes for the precursor polycondensation synthesis of the copolymer polyester PBSX in Examples 46 to 60 are shown in Tables 4-2 and 4-3.

[0155] Table 4-1 Catalysts and reaction process conditions for preparing the polyester PBSX precursor, the modified ester of butanediol succinate, by coupling reaction in Examples 46 to 60

[0156]

[0157] Table 4-2 Process conditions and yields for the precursor polycondensation synthesis of the polyester PBSX in Examples 46 to 60

[0158]

[0159]

[0160] Table 4-3 Performance indexes for the precursor polycondensation synthesis of the polyester PBSX in Examples 46 to 60

[0161] Example Metal content (ppm) Colorimetric L value Melt index (g / 10min) Acid value (mol / t) <![CDATA[Mw(10 4 )]]> Tensile strength (MPa) Example 46 115 79 16 18 18.6 46 Example 47 102 81 19 28 19.2 35 Example 48 95 82 15 23 28.5 29 Example 49 106 80 22 21 23.2 42 Example 50 93 82 18 22 18.2 44 Example 51 86 83 26 32 17.8 48 Example 52 81 84 23 17 16.8 45 Example 53 62 88 29 18 27.5 26 Example 54 82 85 26 30 14.2 47 Example 55 85 83 24 33 15.7 36 Example 56 28 91 33 19 22.5 27 Example 57 58 89 30 20 13.8 46 Example 58 68 87 21 31 13.2 38 Example 59 65 88 19 16 14.6 36 Example 60 72 87 17 20 15.6 42

[0162] As shown in Table 4-1, during the reaction process of preparing the polyester PBSX precursor, the modified ester of butanediol succinate, in Examples 46 to 60, all the solid acid-supported metal bifunctional catalysts and the liquid acid-supported bimetallic composite catalysts were at a temperature of 130 to 170 °C and a feed weight hourly space velocity of 0.2 to 0.4 h -1, under the coupling reaction conditions of hydrogen pressure of 3.5 - 5.5 MPa, molar ratio of hydrogen to unsaturated bond of 20 - 40, and feed molar ratio of diol:diacid or anhydride or ester:modifier = 1.05 - 1.50:1.00:0.05 - 0.20, the C=C or / and C≡C bonds of butynediol, maleic anhydride or butene / alkynedioic acid and dimethyl ester, and the copolymerization modifier can be completely hydrogenated and saturated, and the dianhydride and diol can be completely ring-opening esterified to form the PBSX precursor BS modified ester of polyester. However, due to the chemical equilibrium in the esterification of diacid and diol or the transesterification of dimethyl ester and diol, the esterification or transesterification is incomplete under the pressurized conditions of the coupling reaction. The conversion rate of diacid or dimethyl ester is 81.6 - 86.2 mol%, and the residual rate of diacid or dimethyl ester is 13.8 - 18.4 mol%.

[0163] As shown in Table 4-2 and Table 4-3, the coupling reaction products in Examples 46 - 60 were subjected to a polycondensation process of vacuum distillation oligomerization (temperature 160 - 180 °C, pressure 70 - 90 kPa, and 60 - 90 min), negative pressure flash pre-polymerization (temperature 190 - 210 °C, pressure 10 - 50 kPa, and 45 - 75 min), and vacuum flash final polymerization (temperature 230 - 250 °C, pressure 50 - 90 Pa, and 120 - 180 min) to obtain an effective yield of polyester PBS of 72.36 - 90.73 wt%. Among them, the effective yield of PBS or the raw material utilization rate starting from anhydride is 85.61 - 90.73 wt%. The performance indicators of the PBS polyester products are excellent, with low metal content (28 - 115 ppm), good color (chromaticity L value 80 - 91), low melt index (15 - 33 g / 10 min), low acid value (16 - 33 mol / t), high weight average molecular weight (132,000 - 285,000), and high tensile strength (26 - 48 MPa).

[0164] Comparative Example 1

[0165] Starting from maleic anhydride and butynediol, the monomers and polyester PBS were synthesized by the existing route, including the following steps:

[0166] 1) Preparation of succinic anhydride by hydrogenation of maleic anhydride: Prepare a γ-butyrolactone solution of 15 wt% maleic anhydride, and feed it downward in parallel with hydrogen into a trickle-bed reactor filled with 0.5 wt% Pd / γ-Al 2 O 3 catalyst. At a reaction temperature of 90 °C, hydrogen pressure of 1.0 MPa, and feed space velocity of 1.0 h -1Perform the hydrogenation reaction at a molar ratio of hydrogen anhydride of 20; separate the reaction products into gas and liquid, recycle the hydrogen into the hydrogenation reactor, send the liquid material into the light component removal column, distill off the light components and the solvent γ-butyrolactone from the top of the column, condense and send them into the γ-butyrolactone rectification column, and send the bottom material of the column into the product rectification column; a small amount of water is taken from the top of the γ-butyrolactone rectification column, and the γ-butyrolactone obtained at the bottom of the column is recycled as a hydrogenation solvent; a small amount of heavy components are discharged from the bottom of the product rectification column, and succinic anhydride is obtained at the top of the column.

[0167] 2) Preparation of 1,4-butanediol by hydrogenation of butynediol: Feed butynediol and hydrogen in parallel from top to bottom into a trickle-bed reactor filled with 3.0 wt% Ru - 5.0 wt% Cu / γ-Al 2 O 3 catalyst, and perform the hydrogenation reaction at a reaction temperature of 200 °C, a hydrogen pressure of 3 MPa, a feed space velocity of 2.0 h -1 and a molar ratio of hydrogen to butynediol of 40; separate the reaction products into gas and liquid, recycle the hydrogen into the hydrogenation reactor, send the liquid material into the light component removal column, distill off the light components containing n-butanol from the top of the column, and send the bottom material of the column into the product rectification column; a small amount of heavy components are discharged from the bottom of the product rectification column, and BDO is obtained at the top of the column.

[0168] 3) Esterification of succinic anhydride to prepare a polyester precursor: Weigh succinic anhydride and BDO at a molar ratio of 1.00:1.25, send the monomer raw materials succinic anhydride and BDO into a batching tank, add p-toluenesulfonic acid catalyst at 0.5% of the total mass of the raw materials, stir evenly and heat to 60 °C to prepare the raw materials, and then send them into an esterification reaction kettle. Perform the esterification reaction at a temperature of 180 °C, normal pressure, and a residence time of 60 min. The esterification product is depressurized to 50 kPa to remove small molecules such as water, THF, and BDO to obtain the polyester precursor butylene succinate.

[0169] 4) Polycondensation of the polyester precursor to synthesize polyester PBS: Add tetrabutyl titanate, a polymerization catalyst at 500 ppm of the total mass of succinic anhydride and 1,4-butanediol, to the polyester precursor. After stirring evenly, continuously send it into a prepolymerization reaction kettle, and perform the prepolymerization reaction at a temperature of 210 °C, a pressure of 25 kPa, and a residence time of 60 min; then continuously send the prepolymerization product into a final polymerization reaction kettle, and perform the final polymerization reaction at a temperature of 240 °C, a pressure of 75 Pa, and a residence time of 120 min. The final polymerization product is granulated underwater to obtain polyester PBS pellet products.

[0170] Results: The conversion rate of maleic anhydride hydrogenation to succinic anhydride is 100 mol%, and the total yield of succinic anhydride reaction and purification is 99 mol%; the conversion rate of butynediol hydrogenation to BDO is 100 mol%, and the total yield of BDO reaction and purification is 95 mol%; the effective yield of product PBS (deducting the recovered BDO) based on the feed of maleic anhydride and butynediol is 78.40 wt%; PBS performance indicators: metal content 87 ppm, chromaticity L value 85, melt index 29 g / 10 min, acid value 31 mol / t, weight average molecular weight 16.2×10 4 , tensile strength 44 MPa.

[0171] Comparative Example 2

[0172] Starting from maleic acid and butynediol, monomers and polyester PBS were synthesized by the existing route, including the following steps:

[0173] 1) Hydrogenation of maleic acid to succinic acid: same as step 1) of Comparative Example 1, except that maleic anhydride was replaced with maleic acid.

[0174] 2) Hydrogenation of butynediol to BDO: same as step 2) of Comparative Example 1.

[0175] 3) Esterification of succinic acid to prepare polyester precursor: same as step 3) of Comparative Example 1, except that succinic anhydride was replaced with succinic acid.

[0176] 4) Polycondensation of polyester precursor to synthesize polyester PBS: same as step 4) of Comparative Example 1), except that the dosage of polymerization catalyst tetrabutyl titanate was increased from 500 ppm to 800 ppm.

[0177] Results: The conversion rate of maleic acid hydrogenation to succinic acid is 100 mol%, and the total yield of succinic acid reaction and purification is 99 mol%; the conversion rate of butynediol hydrogenation to BDO is 100 mol%, and the total yield of BDO reaction and purification is 95 mol%; the effective yield of product PBS (deducting the recovered BDO) based on the feed of maleic acid and butynediol is 70.65 wt%; PBS performance indicators: metal content 151 ppm, chromaticity L value 76, melt index 32 g / 10 min, acid value 38 mol / t, weight average molecular weight 14.8×10 4 , tensile strength 39 MPa.

[0178] Comparative Example 3

[0179] Starting from dimethyl maleate and butynediol, monomers and polyester PBS were synthesized by the existing route, including the following steps:

[0180] 1) Hydrogenation of dimethyl maleate to dimethyl succinate: same as step 1) of Comparative Example 1, except that maleic anhydride was replaced with dimethyl maleate.

[0181] 2) Preparation of BDO by hydrogenation of butynediol: The same as step 2) of Comparative Example 1.

[0182] 3) Transesterification of dimethyl succinate to prepare polyester precursor: The same as step 3) of Comparative Example 1, except that succinic anhydride is replaced by dimethyl succinate, and the p-toluenesulfonic acid catalyst with an addition amount of 0.5 wt% is replaced by tetrabutyl titanate with an addition amount of 200 ppm.

[0183] 4) Polycondensation of polyester precursor to synthesize polyester PBS: The same as step 4) of Comparative Example 1, except that the dosage of the polymerization catalyst tetrabutyl titanate is reduced from 500 ppm to 300 ppm.

[0184] Results: The conversion rate of hydrogenation of dimethyl maleate to dimethyl succinate is 100 mol%, and the total yield of reaction and purification of dimethyl succinate is 99 mol%; the conversion rate of hydrogenation of butynediol to prepare BDO is 100 mol%, and the total yield of reaction and purification of BDO is 95 mol%; the effective yield of product PBS (deducting the recovered BDO) based on the feed of dimethyl maleate and butynediol is 61.78 wt%; PBS performance indicators: metal content 106 ppm, chromaticity L value 90, melt index 32 g / 10 min, acid value 15 mol / t, weight average molecular weight 15.5×10 4 , tensile strength 42 MPa.

[0185] Comparative Examples 1 to 3 are typical operation processes of the prior art for synthesizing PBS by using succinic anhydride, succinic acid or dimethyl succinate and BDO as monomers through ring-opening esterification, direct esterification or transesterification methods. Starting from basic chemical raw materials such as maleic anhydride, maleic acid or dimethyl maleate and butene / alkynediol, first hydrogenate maleic anhydride, maleic acid or dimethyl maleate and butene / alkynediol under the action of a hydrogenation catalyst to prepare monomer raw materials succinic anhydride, succinic acid or dimethyl succinate and BDO, and then ring-open esterify, directly esterify or transesterify succinic anhydride, succinic acid or dimethyl succinate and BDO under the action of an esterification / transesterification catalyst to prepare the polyester precursor butylene succinate, and then the precursor is polycondensed under the action of a polymerization catalyst to synthesize the polyester PBS. The operation process for synthesizing the polyester PBS precursor in the examples is to prepare the precursor by one-step esterification / transesterification-hydrogenation under the action of a solid acid-supported metal bifunctional catalyst or an acid-metal composite catalyst, and then the precursor is polycondensed to synthesize PBS. For example, in Examples 1 to 9 and 23, maleic anhydride and butene / alkynediol are used to prepare the precursor by one-step ring-opening esterification-hydrogenation, in Examples 10, 11, 24, 25 and 28, maleic / alkynedioic acid and butene / alkynediol are used to prepare the precursor by one-step direct esterification-hydrogenation, and in Examples 12, 13, 26, 27 and 29, dimethyl maleic / alkynedioate and butene / alkynediol are used to prepare the precursor by one-step direct transesterification-hydrogenation. Obviously, the three processes of hydrogenating butene / alkynediol in the prior art to monomer BDO, 4 hydrogenating unsaturated diacid / anhydride / ester to monomer C 4 saturated diacid / anhydride / ester, and 4 preparing the polyester precursor by esterification / transesterification of saturated diacid / anhydride / ester and BDO are coupled into one step, which simplifies the process and operation flow, reduces the reaction and separation steps, and reduces the investment in devices and equipment. The technical core for its realization is the development of a high-performance dual-functional or composite catalyst.

[0186] Comparing Examples 1 to 9 and 23 starting from maleic anhydride and butene / butynediol with Comparative Example 1, the effective yield of the polyester synthesized by using the coupled reaction path is 86.08 - 91.52 wt%, which is significantly higher than the effective yield of 78.40 wt% of the polyester synthesized by using the existing reaction path. At the same time, the comprehensive performance indexes of the polyester (metal content 29 - 96 ppm, chromaticity L value 83 - 91, melt index 13 - 28 g / 10 min, acid value 19 - 29 mol / t, weight-average molecular weight 16.8 - 18.9×10 4 and tensile strength 43 - 49 MPa) are also better than those of the polyester synthesized by using the existing reaction path (metal content 87 ppm, chromaticity L value 85, melt index 29 g / 10 min, acid value 31 mol / t, weight-average molecular weight 16.2×10 4and a tensile strength of 44 MPa). Comparing Examples 10, 11, 24, 25, and 28 starting from butene / alkynedioic acid and butene / butynediol with Comparative Example 2, the effective yield of the polyester synthesized by the coupling reaction path is 81.88 - 83.52 wt%, significantly higher than the effective yield of 70.65 wt% of the polyester synthesized by the existing reaction path. At the same time, the comprehensive performance indicators of the polyester (metal content 31 - 64 ppm, chromaticity L value 87 - 90, melt index 22 - 32 g / 10 min, acid value 30 - 36 mol / t, weight average molecular weight 14.2 - 15.5×10 4 and a tensile strength of 39 - 42 MPa) are also superior to those of the polyester synthesized by the existing reaction path (metal content 151 ppm, chromaticity L value 76, melt index 32 g / 10 min, acid value 38 mol / t, weight average molecular weight 14.8×10 4 and a tensile strength of 39 MPa). Comparing Examples 12, 13, 26, 27, and 29 starting from dimethyl butene / alkynedioate and butene / butynediol with Comparative Example 3, the effective yield of the polyester synthesized by the coupling reaction path is 71.5 - 72.01 wt%, significantly higher than the effective yield of 61.78 wt% of the polyester synthesized by the existing reaction path. At the same time, the comprehensive performance indicators of the polyester (metal content 51 - 86 ppm, chromaticity L value 87 - 90, melt index 20 - 24 g / 10 min, acid value 18 - 22 mol / t, weight average molecular weight 16.3 - 17.2×10 4 and a tensile strength of 43 - 46 MPa) are also superior to those of the polyester synthesized by the existing reaction path (metal content 106 ppm, chromaticity L value 90, melt index 32 g / 10 min, acid value 15 mol / t, weight average molecular weight 15.5×10 4 , tensile strength 42 MPa).

[0187] Special statement: The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for producing polybutylene succinate polyester using C4 unsaturated dibasic oxygen-containing compounds as raw materials, characterized in that: The steps include: (1) In a fixed bed or slurry bed reactor, in the presence of a solid acid-supported metal bifunctional catalyst or an acid-metal composite catalyst, using C4 unsaturated diol and C4 diacid and / or its anhydride or / and its ester as raw materials, with or without adding a copolymerization modifier, through esterification-hydrogenation or ester exchange-hydrogenation coupling reaction, and then through distillation separation, to continuously prepare polyester precursor butanediol succinate or modified ester; (2) in a tank reactor, in the presence of a polymerization catalyst, the polyester precursor butylene succinate prepared in step (1) is subjected to a reaction distillation condensation polymerization process including reduced pressure distillation polymerization, negative pressure flash prepolymerization, and vacuum flash final polymerization in sequence, with or without the addition of a copolymerization modifier, to continuously synthesize polybutylene succinate or a modified copolyester; Wherein, the solid acid-supported metal bifunctional catalyst is a catalyst prepared by loading a metal active component with a hydrogenation function or a metal active component and an auxiliary agent onto a solid acid carrier with an esterification / ester exchange function; the acid-metal composite catalyst is a catalyst prepared by uniformly mixing a metal catalyst with a hydrogenation function and an acid catalyst with an esterification / ester exchange function, the metal catalyst includes a bulk metal catalyst or a supported metal catalyst, and the acid catalyst is selected from at least one of a solid acid or a liquid acid; the options of the solid acid carrier in the solid acid-supported metal bifunctional catalyst and the solid acid in the acid catalyst include bulk, supported or solid-supported solid acids; The copolymer modifier is selected from at least one of copolymerized dibasic acid, dibasic acid ester, cyclic anhydride, polyol, cyclic ether, hydroxy acid, hydroxy acid ester, lactone or polyhydroxy acid.

2. The method for producing polybutylene succinate polyester using C4 unsaturated dibasic oxygen-containing compounds as raw materials according to claim 1, characterized in that: Step (1) specifically includes the following process: S11. The raw materials C4 unsaturated diol and C4 diacid and / or its anhydride or / and at least one of its esters are heated and melted to prepare a raw material solution with or without adding a copolymerization modifier according to a stoichiometric ratio; S12-1. Using a fixed bed reactor, the raw material solution prepared in step S11 is preheated and transported to a fixed bed reactor filled with solid acid-supported metal bifunctional catalyst particles or solid acid-metal composite catalyst particles that have been pre-reduced and activated, and esterification-hydrogenation or transesterification-hydrogenation coupling reaction is performed; S13-1. The coupling reaction product is subjected to gas-liquid separation, and part or all of the liquid phase material is sent to a flash tower, and the light components are removed from the top of the tower, and a material containing a polyester precursor butanediol succinate or a modified ester is obtained in the bottom of the tower; or, S12-2. A slurry bed reactor is used to divide the raw material solution prepared in step S11 into two paths, wherein 2 to 8 wt% of the raw material solution is fed into a catalyst slurry preparation tank, mixed with a solid acid-supported metal bifunctional catalyst powder, or a solid acid-metal composite catalyst powder or a liquid acid + metal catalyst powder composition and stirred to prepare a catalyst slurry; and another path is used to preheat 92 to 98 wt% of the raw material solution, and then fed into a slurry bed reactor simultaneously with the prepared catalyst slurry to perform an esterification-hydrogenation or ester exchange-hydrogenation coupling reaction; S13-2. The coupling reaction product is subjected to gas-liquid separation, and the liquid phase material is partially or completely fed to a flash tower, and the light components are removed from the top of the tower. The filtrate of the bottom material after filtration is a liquid phase material containing a polyester precursor butylene succinate or a modified ester, and the filter cake is a coupling reaction catalyst and is recycled for the preparation of a catalyst slurry; Wherein, in steps S13-1 and S13-2, the operating conditions of the flash tower are: bottom temperature of 50-120°C, top temperature of 40-105°C and top pressure of 90-101 kPa.

3. The method for producing polybutylene succinate polyester using C4 unsaturated dibasic oxygen-containing compounds as raw materials according to claim 1, characterized in that: Step (2) specifically includes the following process: S21. Adding part of the polymerization catalyst to the polyester precursor material obtained in step (1), with or without adding a copolymerization modifier, mixing well and feeding into a polymerization reactor for vacuum reaction and distillation to obtain an oligomer material; S22. The remaining polymerization catalyst is added to the oligomer material prepared in step S21, mixed evenly and then fed into a prepolymerization reactor, and flash precondensed under negative pressure to obtain a prepolymerized product; S23. The prepolymer product prepared in step S22 is fed into a final polymerization reactor, and flashed and polycondensed under vacuum to obtain a final polymerization product, which is then pelletized underwater to obtain a polybutylene succinate or modified copolyester pellet product; Wherein, in step S21, the amount of the polymerization catalyst used is 0 to 30% of the total amount of the polymerization catalyst.

4. The method for producing polybutylene succinate polyester using C4 unsaturated dibasic oxygen-containing compounds as raw materials according to claim 1, characterized in that: In step (1), the coupling reaction process conditions for preparing the polyester precursor are: the raw material solution feed space velocity is 0.05 to 2.00 h -1 , the molar ratio of hydrogen to carbon-carbon unsaturated bonds is 5 to 100, the reaction temperature is 60 to 200° C., the reaction pressure is 1.0 to 8.0 MPa, and the molar ratio of C4 diacid and / or its anhydride and / or its ester: C4 unsaturated diol: copolymer modifier is 1.00:(0.50 to 6.00):(0 to 3.00); Preferably, the raw material solution feed space velocity is 0.10 to 1.00 h -1 , the molar ratio of hydrogen to carbon-carbon unsaturated bonds is 10-80, the reaction temperature is 80-180°C, and the reaction pressure is 1.5-6.0MPa; More preferably, the liquid raw material feed space velocity is 0.2 to 0.6 h -1 , the molar ratio of hydrogen to carbon-carbon unsaturated bonds is 20-50, the reaction temperature is 100-160°C, and the reaction pressure is 2.0-4.5MPa.

5. A method for producing polybutylene succinate polyester using C4 unsaturated dibasic oxygen-containing compounds as raw materials according to any one of claims 1 or 4, characterized in that: In step (1), when no copolymer modifier is added, the molar ratio of C4 diacid and / or its anhydride and / or its ester:C4 unsaturated diol is 1.00:(1.10-1.50); ​​preferably, the molar ratio of C4 diacid and / or its anhydride and / or its ester:C4 unsaturated diol is 1.00:(1.15-1.35); or, When a copolymer modifier is added in step (1), the molar ratio of C4 diacid and / or its anhydride and / or its ester: C4 unsaturated diol: copolymerized dibasic acid and / or dibasic acid ester and / or cyclic anhydride is 1.00: (1.15-4.50): (0.05-2.00), or the molar ratio of C4 diacid and / or its anhydride and / or its ester: C4 unsaturated diol: copolymerized polyol and / or cyclic ether is 1.00: (0.55-1.45): (0.55-0.05), or the molar ratio of C4 diacid and / or its anhydride and / or its ester: C4 unsaturated diol: copolymerized hydroxy acid or its ester or lactone or polyhydroxy acid is 1.00: (1.10-1.50): (0.05-2.00). 2.00); preferably, the molar ratio of C4 diacid and / or its anhydride and / or its ester: C4 unsaturated diol: copolymerized dibasic acid and / or dibasic acid ester and / or cyclic anhydride is 1.00:(1.25-2.70):(0.10-1.00), or the molar ratio of C4 diacid and / or its anhydride and / or its ester: C4 unsaturated diol: copolymerized polyol and / or its cyclic ether is 1.00:(0.90-1.25):(0.25-0.10), or the molar ratio of C4 diacid and / or its anhydride and / or its ester: C4 unsaturated diol: copolymerized hydroxy acid or its ester or lactone or polyhydroxy acid is 1.00:(1.15-1.35):(0.10-1.00).

6. The method for producing polybutylene succinate polyester using C4 unsaturated dibasic oxygen-containing compounds as raw materials according to claim 1, characterized in that: In step (1), in the solid acid-supported metal bifunctional catalyst, the metal active component is one element selected from Fe, Co, Ni, Cu, Ru, Pd, Pt or Ag or a combination thereof, and the auxiliary agent is an oxide of Mg, Ca, Sn, Pb, Y, La, Ce, Sm or Nd, or an oxide of B, P, Mo, W or Zn, or a combination of these two types of oxides; wherein the loading amount of the metal active component is 0.05 to 30 wt%, and the loading amount of the auxiliary agent is 0.02 to 20 wt%; Preferably, the metal active component is a single metal such as Ni, Ru, Pd, or Pt, or a bimetal such as Ni-Cu, Ni-Co, Ni-Ru, Ni-Pd, Pd-Fe, Pd-Ru, or Pt-Co; the metal active component is a noble metal active component with a loading amount of 0.2 to 2 wt%, or / and a non-noble metal active component with a loading amount of 5.0 to 20 wt%; the auxiliary agent is an oxide of Mg, Sn, La, or Ce, or an oxide of Mo, W, or Zn, or a combination of these two types of oxides; the auxiliary agent is an alkaline earth or rare earth oxide auxiliary agent with a loading amount of 0.1 to 1.0 wt%, or other oxide auxiliary agents with a loading amount of 1.0 to 10 wt%.

7. The method for producing polybutylene succinate polyester using C4 unsaturated dibasic oxygen-containing compounds as raw materials according to claim 1, characterized in that: In step (1), in the acid-metal composite catalyst, the metal catalyst is a bulk or supported metal catalyst, and the acid catalyst is a solid acid or a liquid acid; wherein: The bulk metal catalyst is a modified skeleton metal catalyst or an amorphous alloy catalyst, selected from at least one of Ni-Al-M catalysts, M includes Mg, Sr, B, Sn, La, Ti, Cr, Mo, W, Mn, Fe, Co, Cu or Zn; preferably, in the Ni-Al-M catalyst, M is selected from at least one of Mo, Co, Cu and Ti; The supported metal catalyst includes porous carriers AC, CMK, CNT, GPE, SiO2, MS, γ-Al2O3, θ-Al2O3, MA, SiO2-Al2O3, TiO2, ZrO2, HM, HHEU, Hβ, HZSM-5, HZSM-11, HZSM-12, HZSM-18, HZSM-22, HZSM-23, HZSM-35, HZSM-48, HMCM-22, HMCM-41, HMCM-48, HMCM-49, HMCM-50, HMCM-56, AlPO4-11, SAPO-11, SAPO-34, ZRP-3, S-1, S- 2. At least one of TS-1, TS-2, SBA-1, SBA-15, ZEO-1, ZEO-2, ZEO-3, KIT-6, SCM-14, SCM-15 and SCM-25 is loaded with a single metal Ni, Ru, Pd, Pt with or without a promoter, or a bimetallic combination of Ni, Ru, Pd, Pt or a bimetallic or multimetallic catalyst of at least one of Al, Mg, Sr, Sn, La, Ti, Cr, Mo, W, Mn, Fe, Co, Cu or Zn, wherein the promoter is one or more oxides of Mg, Ca, Sn, Pb, Y, La, Ce, Sm, Nd, B, P, Mo, W or Zn; In step (1), the liquid acid comprises an alkyl sulfonic acid, an aryl sulfonic acid or a halogenated organic acid or a salt thereof, and a metal halide or a metal organic complex; preferably at least one of methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, trifluoroacetic acid, trifluoromethanesulfonic acid, bistrifluoromethanesulfonimide, samarium trifluoromethanesulfonate, neodymium trifluoromethanesulfonate, ferric chloride, titanium tetrachloride, antimony pentafluoride, tantalum hexafluoride, dichlorotitanocene, tetrabutyl titanate, titanium butanediol or dibutyltin oxide.

8. A method for producing polybutylene succinate polyester using C4 unsaturated dibasic oxygen-containing compounds as raw materials according to any one of claims 1 or 7, characterized in that: In step (1), the bulk solid acid in the solid acid is selected from at least one of a hydrogen-type zeolite molecular sieve, an acidic oxide, a solid superacid or a hydrogen-type cation exchange resin; wherein: The hydrogen-type zeolite molecular sieve is selected from HM, HHEU, HY, Hβ, HZSM-5, HZSM-11, HZSM-12, HZSM-18, HZSM-22, HZSM-23, HZSM-35, HZSM-48, HMCM-22, HMCM-41, HMCM-48, HMCM-49, HMCM-50 or HMCM-56; The acidic oxide includes γ-Al2O3, Fe2O3, MoO3, Nb2O5 or H2TiO3, or an acid, isopolyacid, heteropolyacid or salt thereof of phosphorus, arsenic, selenium, tellurium, antimony, vanadium, molybdenum or tungsten, preferably H3PO4, H6TeO6, H2WO4, Ca(H2PO4)2, Al(H2PO4)3, AlPO4, Zr(HPO4)2, FePO4, VPO x 、H3PW 12 O 40 、H3PMo 12 O 40 、H4SiW 12 O 40 、H4SiMo 12 O 40 or Cs 2.5 H 0.5 PW 12 O 40 ; The solid superacid is selected from SO4 2- / ZrO2、SO4 2- / TiO2、SO4 2- / Fe2O3、SO4 2- / ZrO2-La2O3, SO4 2- / ZrO2-CeO2, SO4 2- / TiO2-ZrO2, SO4 2- / ZrO2-CeO2-Fe2O3, WO3 / ZrO2 or MoO3 / ZrO2, preferably SO4 2- / ZrO2-La2O3, SO4 2- / ZrO2-CeO2-Fe2O3, WO3 / ZrO2 or MoO3 / ZrO2; The hydrogen type cation exchange resin is selected from Amberlyst series A-15, A-16 or A-35, or Amberlite IRC series IRC-50, IRC-76 or IRC-86, or Amberlite FPC series FPC-11, FPC-22 or FPC-3500, or Amberjet series A-1000 or A-1200, or NKC-9, HPK-16, D-001, D-61, D-72, D-113, D-732 or T-62, SB-DH, CR-11, or chlorinated or fluorinated resin; preferably A-15, A-35, IRC-76, A-1200, NKC-9, HPK-16, D-72, T-62 or Nafinon-H.

9. A method for producing polybutylene succinate polyester using C4 unsaturated dibasic oxygen-containing compounds as raw materials according to any one of claims 1 or 7, characterized in that: In step (1), the supported solid acid in the solid acid comprises a supported solid acid in which an acidic oxide or a solid superacid is supported on a porous carrier, and the supported solid acid has a supported amount of 10 to 60 wt%, preferably 20 to 40 wt%; the supported solid acid in the solid acid is a solid acid obtained by supporting a liquid acid on a porous carrier, and the supported solid acid has a supported amount of 5 to 40 wt%, preferably 10 to 30 wt%; wherein: The acidic oxide supported by the supported solid acid includes oxides, isopoly acids, heteropoly acids or salts thereof of phosphorus, arsenic, selenium, tellurium, antimony, vanadium, molybdenum or tungsten, preferably MoO3, Nb2O5, H3PO4, H6TeO6, H2WO4, Al(H2PO4)3, AlPO4, Zr(HPO4)2, VPO x 、H3PW 12 O 40 、H3PMo 12 O 40 、H4SiW 12 O 40 、H4SiMo 12 O 40 or Cs 2.5 H 0.5 PW 12 O 40 ; The solid superacid supported by the supported solid acid includes SO4 2- / ZrO2、SO4 2- / TiO2、SO4 2- / Fe2O3、SO4 2- / ZrO2-La2O3, SO4 2- / ZrO2-CeO2, SO4 2- / TiO2-ZrO2, WO3 / ZrO2 or MoO3 / ZrO2; The liquid acid immobilized by the solid-supported solid acid includes a grafted halogenated organic acid or an inorganic halide, a directly impregnated inorganic liquid acid or a metal salt; preferably chloroformic acid, chloroacetic acid, chloropropionic acid, fluoroacetic acid, chlorosulfonic acid or fluorosulfonic acid and salts thereof, chlorides or fluorides of boron, aluminum, gallium, indium, germanium, tin, phosphorus, arsenic, antimony, sulfur, selenium, tellurium, titanium, zirconium, vanadium, chromium, manganese, iron or zinc, or sulfuric acid or phosphoric acid; more preferably monochloroformic acid, monochloroacetic acid, trichloroacetic acid, trifluoroacetic acid, chlorosulfonic acid, trifluoromethanesulfonic acid, samarium trifluoromethanesulfonate, neodymium trifluoromethanesulfonate, boron trifluoride, aluminum trichloride, germanium tetrachloride, phosphorus pentachloride, antimony pentafluoride, titanium tetrachloride, zirconium tetrachloride, ferric chloride, zinc dichloride or phosphoric acid; The porous carrier is selected from at least one of activated carbon, mesoporous carbon, carbon nanotubes, graphene, silicon oxide, aluminum oxide, silicon aluminum microspheres, titanium oxide, zirconium oxide or molecular sieves; preferably at least one of AC, CMK, amorphous SiO2, silica gel, mesoporous silica, amorphous Al2O3, γ-Al2O3, θ-Al2O3, pseudo-boehmite, mesoporous alumina, SiO2-Al2O3, TiO2, ZrO2, HM, HHEU, Hβ, HZSM-5, HZSM-22, HMCM-22, HMCM-41, HMCM-48, HMCM-49, HMCM-56, AlPO4-11, SAPO-11, SAPO-34, Silicalite-1, Silicalite-2, TS-1, TS-2, SBA-15, ZEO-1, ZEO-3, KIT-6 or SCM-14.

10. The method for producing polybutylene succinate polyester using C4 unsaturated dibasic oxygen-containing compounds as raw materials according to claim 1, characterized in that: In step (2), the polymerization catalyst is selected from at least one of titanium trichloride, titanium tetrachloride, tributoxytitanium chloride, tetraethyl titanate, tetraisopropyl titanate, tetrabutyl titanate, tetraisooctyl titanate, tetrahydroxyethyl titanate, tetrahydroxypropyl titanate, tetrahydroxybutyl titanate, diethylene glycol titanate, dipropylene glycol titanate or dibutylene glycol titanate; the polymerization catalyst is used in an amount of 0.005 to 0.500% of the total mass of the raw materials, preferably 0.010 to 0.100%; The polymerization reaction conditions are: polymerization reaction temperature 150-190° C., pressure 50-100 kPa and material residence time 45-120 min; preferably, polymerization reaction temperature 160-180° C., pressure 70-90 kPa and material residence time 60-90 min; The prepolymerization reaction conditions are: prepolymerization reaction temperature 180-220° C., pressure 5-50 kPa and material residence time 30-90 min, preferably, prepolymerization reaction temperature 190-210° C., pressure 10-30 kPa and material residence time 45-75 min; The final polymerization reaction conditions are: final polymerization reaction temperature 200-260° C., pressure 10-200 Pa and material residence time 75-180 min. Preferably, the final polymerization reaction temperature 220-240° C., pressure 50-90 Pa and material residence time 90-120 min.

11. A method for producing polybutylene succinate polyester using C4 unsaturated dibasic oxygen-containing compounds as raw materials according to any one of claims 1 or 5, characterized in that: The C4 unsaturated diol is a C4 diol containing a C=C bond or a C≡C bond, preferably butenediol or butynediol; The C4 diacid, anhydride or ester includes a C4 saturated or unsaturated dibasic acid, anhydride or ester, preferably methylmalonic acid, methylenemalonic acid, succinic acid, maleic acid, fumaric acid, butynedioic acid, succinic anhydride, maleic anhydride or their monoesters or diesters; The copolymerized dibasic acid, dibasic acid ester or cyclic anhydride includes C2 to C4 diacids, anhydrides and esters. 20 aliphatic, aromatic or heterocyclic dibasic acid or cyclic anhydride or ester; preferably methylsuccinic acid, methylsuccinic anhydride, glutaric acid, glutaric anhydride, adipic acid, adipic anhydride, pimelic acid, suberic acid, azelaic acid, sebacic acid, cyclohexanedicarboxylic acid, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, phthalic acid, phthalic anhydride, naphthalene dicarboxylic acid, biphenyl dicarboxylic acid, biphenyl dicarboxylic anhydride, furandicarboxylic acid, tetrahydrofuran dicarboxylic acid, pyran dicarboxylic acid, tetrahydropyran dicarboxylic acid, pyrrole dicarboxylic acid, tetrahydropyrrole dicarboxylic acid, pyridine dicarboxylic acid, piperidine dicarboxylic acid or thiophene dicarboxylic acid, or glutaconic acid, glutaconic anhydride, itaconic acid, itaconic anhydride, nadic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexenedicarboxylic acid, heptenedicarboxylic acid, octenedicarboxylic acid, nonenedicarboxylic acid or decanedicarboxylic acid, or mono- or diesters thereof; The copolymerized polyol or cyclic ether includes C2 to C4 unsaturated diols 20 Aliphatic, aromatic or heterocyclic dihydric or higher alcohols or cyclic ethers, as well as polyether polyols or polyester polyols; preferably ethylene glycol, 1,3-propylene glycol, 1,4-butylene glycol, 2-methyl-1,3-propanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, glycerol, trimethylolethane, 1,2,6-hexanetriol, trimethylolpropane, erythritol, pentaerythritol, xylitol, sorbitol, mannitol , inositol, 1-phenyl-1,3-propanediol, 2-phenyl-1,3-propanediol, 1-phenyl-1,4-butanediol, isophthalic acid alcohol, phthalic acid alcohol, 2,6-naphthalenedimethanol, 2,2′-biphenyl dimethanol, 4,4′-biphenyl dimethanol, 2,5-furan dimethanol, 2,6-pyridinium dimethanol, diethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polybutylene glycol, polybutylene succinate glycol, polyethylene terephthalate glycol, ethylene oxide, propylene oxide, epichlorohydrin, glycidol, tetrahydrofuran, tetrahydrofurfuryl alcohol or tetrahydropyran; The copolyhydroxy acid, hydroxy acid ester, lactone or polyhydroxy acid comprises C2 to C 20 Hydroxylic acid, hydroxy acid ester or lactone, and polyhydroxy acid; preferably glycolic acid, lactic acid, 3-hydroxypropionic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 5-hydroxyvaleric acid, 6-hydroxycaproic acid or their methyl esters, or β-propiolactone, γ-butyrolactone, γ-valerolactone, δ-valerolactone or ε-caprolactone, or polyglycolic acid, polylactic acid, poly 3-hydroxypropionic acid, poly 3-hydroxybutyric acid, poly γ-butyrolactone or polycaprolactone.

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