CN114524924A - Regenerated polyester and preparation method and application thereof - Google Patents
Regenerated polyester and preparation method and application thereof Download PDFInfo
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- CN114524924A CN114524924A CN202011322930.0A CN202011322930A CN114524924A CN 114524924 A CN114524924 A CN 114524924A CN 202011322930 A CN202011322930 A CN 202011322930A CN 114524924 A CN114524924 A CN 114524924A
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- polyester
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- 229920000728 polyester Polymers 0.000 title claims abstract description 223
- 238000002360 preparation method Methods 0.000 title abstract description 20
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims abstract description 100
- 238000006136 alcoholysis reaction Methods 0.000 claims abstract description 71
- 238000000034 method Methods 0.000 claims abstract description 59
- KKEYFWRCBNTPAC-UHFFFAOYSA-N Terephthalic acid Chemical compound OC(=O)C1=CC=C(C(O)=O)C=C1 KKEYFWRCBNTPAC-UHFFFAOYSA-N 0.000 claims abstract description 50
- 238000006068 polycondensation reaction Methods 0.000 claims abstract description 41
- 239000000463 material Substances 0.000 claims abstract description 39
- 239000007788 liquid Substances 0.000 claims abstract description 16
- 239000007790 solid phase Substances 0.000 claims abstract description 14
- 239000012535 impurity Substances 0.000 claims abstract description 12
- 238000001035 drying Methods 0.000 claims abstract description 10
- 238000001816 cooling Methods 0.000 claims abstract description 9
- 238000007599 discharging Methods 0.000 claims abstract description 9
- 238000002156 mixing Methods 0.000 claims abstract description 8
- QQVIHTHCMHWDBS-UHFFFAOYSA-N isophthalic acid Chemical compound OC(=O)C1=CC=CC(C(O)=O)=C1 QQVIHTHCMHWDBS-UHFFFAOYSA-N 0.000 claims description 56
- 238000006243 chemical reaction Methods 0.000 claims description 43
- 239000002253 acid Substances 0.000 claims description 33
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 32
- SLCVBVWXLSEKPL-UHFFFAOYSA-N neopentyl glycol Chemical compound OCC(C)(C)CO SLCVBVWXLSEKPL-UHFFFAOYSA-N 0.000 claims description 31
- IKHGUXGNUITLKF-UHFFFAOYSA-N Acetaldehyde Chemical compound CC=O IKHGUXGNUITLKF-UHFFFAOYSA-N 0.000 claims description 18
- 238000003756 stirring Methods 0.000 claims description 17
- 239000003054 catalyst Substances 0.000 claims description 16
- 239000003381 stabilizer Substances 0.000 claims description 13
- 150000007513 acids Chemical class 0.000 claims description 11
- KLDXJTOLSGUMSJ-JGWLITMVSA-N Isosorbide Chemical compound O[C@@H]1CO[C@@H]2[C@@H](O)CO[C@@H]21 KLDXJTOLSGUMSJ-JGWLITMVSA-N 0.000 claims description 10
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims description 10
- 229960002479 isosorbide Drugs 0.000 claims description 10
- 150000001875 compounds Chemical class 0.000 claims description 9
- 238000001914 filtration Methods 0.000 claims description 9
- 239000000155 melt Substances 0.000 claims description 9
- 230000008569 process Effects 0.000 claims description 9
- 229920000180 alkyd Polymers 0.000 claims description 8
- PYKYMHQGRFAEBM-UHFFFAOYSA-N anthraquinone Natural products CCC(=O)c1c(O)c2C(=O)C3C(C=CC=C3O)C(=O)c2cc1CC(=O)OC PYKYMHQGRFAEBM-UHFFFAOYSA-N 0.000 claims description 7
- 150000004056 anthraquinones Chemical class 0.000 claims description 7
- 239000000049 pigment Substances 0.000 claims description 7
- 230000035484 reaction time Effects 0.000 claims description 7
- 230000001476 alcoholic effect Effects 0.000 claims description 6
- 150000001298 alcohols Chemical class 0.000 claims description 6
- 239000012752 auxiliary agent Substances 0.000 claims description 6
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims description 5
- XZZNDPSIHUTMOC-UHFFFAOYSA-N triphenyl phosphate Chemical compound C=1C=CC=CC=1OP(OC=1C=CC=CC=1)(=O)OC1=CC=CC=C1 XZZNDPSIHUTMOC-UHFFFAOYSA-N 0.000 claims description 5
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 4
- MHOFGBJTSNWTDT-UHFFFAOYSA-M 2-[n-ethyl-4-[(6-methoxy-3-methyl-1,3-benzothiazol-3-ium-2-yl)diazenyl]anilino]ethanol;methyl sulfate Chemical compound COS([O-])(=O)=O.C1=CC(N(CCO)CC)=CC=C1N=NC1=[N+](C)C2=CC=C(OC)C=C2S1 MHOFGBJTSNWTDT-UHFFFAOYSA-M 0.000 claims description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 3
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 3
- 229910052787 antimony Inorganic materials 0.000 claims description 3
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 claims description 3
- 239000001045 blue dye Substances 0.000 claims description 3
- 239000001055 blue pigment Substances 0.000 claims description 3
- 229910052793 cadmium Inorganic materials 0.000 claims description 3
- BDOSMKKIYDKNTQ-UHFFFAOYSA-N cadmium atom Chemical compound [Cd] BDOSMKKIYDKNTQ-UHFFFAOYSA-N 0.000 claims description 3
- XCJYREBRNVKWGJ-UHFFFAOYSA-N copper(II) phthalocyanine Chemical compound [Cu+2].C12=CC=CC=C2C(N=C2[N-]C(C3=CC=CC=C32)=N2)=NC1=NC([C]1C=CC=CC1=1)=NC=1N=C1[C]3C=CC=CC3=C2[N-]1 XCJYREBRNVKWGJ-UHFFFAOYSA-N 0.000 claims description 3
- 239000001056 green pigment Substances 0.000 claims description 3
- IEQIEDJGQAUEQZ-UHFFFAOYSA-N phthalocyanine Chemical compound N1C(N=C2C3=CC=CC=C3C(N=C3C4=CC=CC=C4C(=N4)N3)=N2)=C(C=CC=C2)C2=C1N=C1C2=CC=CC=C2C4=N1 IEQIEDJGQAUEQZ-UHFFFAOYSA-N 0.000 claims description 3
- 229920000137 polyphosphoric acid Polymers 0.000 claims description 3
- ISIJQEHRDSCQIU-UHFFFAOYSA-N tert-butyl 2,7-diazaspiro[4.5]decane-7-carboxylate Chemical compound C1N(C(=O)OC(C)(C)C)CCCC11CNCC1 ISIJQEHRDSCQIU-UHFFFAOYSA-N 0.000 claims description 3
- 229910052719 titanium Inorganic materials 0.000 claims description 3
- 239000010936 titanium Substances 0.000 claims description 3
- WVLBCYQITXONBZ-UHFFFAOYSA-N trimethyl phosphate Chemical compound COP(=O)(OC)OC WVLBCYQITXONBZ-UHFFFAOYSA-N 0.000 claims description 3
- 229910052725 zinc Inorganic materials 0.000 claims description 3
- 239000011701 zinc Substances 0.000 claims description 3
- 239000000413 hydrolysate Substances 0.000 claims description 2
- 239000000126 substance Substances 0.000 abstract description 8
- 231100000252 nontoxic Toxicity 0.000 abstract description 4
- 230000003000 nontoxic effect Effects 0.000 abstract description 4
- 239000002994 raw material Substances 0.000 abstract description 4
- 231100000053 low toxicity Toxicity 0.000 abstract description 2
- 238000005886 esterification reaction Methods 0.000 description 14
- 230000001276 controlling effect Effects 0.000 description 12
- 150000002148 esters Chemical group 0.000 description 12
- 239000007789 gas Substances 0.000 description 12
- 239000000047 product Substances 0.000 description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 9
- 238000005266 casting Methods 0.000 description 8
- 238000004806 packaging method and process Methods 0.000 description 8
- 238000004064 recycling Methods 0.000 description 8
- QPKOBORKPHRBPS-UHFFFAOYSA-N bis(2-hydroxyethyl) terephthalate Chemical compound OCCOC(=O)C1=CC=C(C(=O)OCCO)C=C1 QPKOBORKPHRBPS-UHFFFAOYSA-N 0.000 description 7
- 230000001105 regulatory effect Effects 0.000 description 7
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- 230000032050 esterification Effects 0.000 description 6
- 238000006116 polymerization reaction Methods 0.000 description 6
- WSXIMVDZMNWNRF-UHFFFAOYSA-N antimony;ethane-1,2-diol Chemical compound [Sb].OCCO WSXIMVDZMNWNRF-UHFFFAOYSA-N 0.000 description 4
- 238000002425 crystallisation Methods 0.000 description 4
- 239000012153 distilled water Substances 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 229920000139 polyethylene terephthalate Polymers 0.000 description 4
- 239000005020 polyethylene terephthalate Substances 0.000 description 4
- -1 Polyethylene terephthalate Polymers 0.000 description 3
- DNIAPMSPPWPWGF-UHFFFAOYSA-N Propylene glycol Chemical compound CC(O)CO DNIAPMSPPWPWGF-UHFFFAOYSA-N 0.000 description 3
- 230000008025 crystallization Effects 0.000 description 3
- 238000005520 cutting process Methods 0.000 description 3
- 239000000539 dimer Substances 0.000 description 3
- WOZVHXUHUFLZGK-UHFFFAOYSA-N dimethyl terephthalate Chemical compound COC(=O)C1=CC=C(C(=O)OC)C=C1 WOZVHXUHUFLZGK-UHFFFAOYSA-N 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 230000001737 promoting effect Effects 0.000 description 3
- 239000006227 byproduct Substances 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 239000000178 monomer Substances 0.000 description 2
- XNGIFLGASWRNHJ-UHFFFAOYSA-N phthalic acid Chemical compound OC(=O)C1=CC=CC=C1C(O)=O XNGIFLGASWRNHJ-UHFFFAOYSA-N 0.000 description 2
- 238000000053 physical method Methods 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 238000011069 regeneration method Methods 0.000 description 2
- 238000007086 side reaction Methods 0.000 description 2
- 239000003440 toxic substance Substances 0.000 description 2
- 238000005809 transesterification reaction Methods 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- REIDAMBAPLIATC-UHFFFAOYSA-N 4-methoxycarbonylbenzoic acid Chemical compound COC(=O)C1=CC=C(C(O)=O)C=C1 REIDAMBAPLIATC-UHFFFAOYSA-N 0.000 description 1
- 238000005903 acid hydrolysis reaction Methods 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000005034 decoration Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- BTVWZWFKMIUSGS-UHFFFAOYSA-N dimethylethyleneglycol Natural products CC(C)(O)CO BTVWZWFKMIUSGS-UHFFFAOYSA-N 0.000 description 1
- 238000010494 dissociation reaction Methods 0.000 description 1
- 230000005593 dissociations Effects 0.000 description 1
- 229920006351 engineering plastic Polymers 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000005453 pelletization Methods 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000010926 purge Methods 0.000 description 1
- 239000001054 red pigment Substances 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Images
Classifications
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/78—Preparation processes
- C08G63/80—Solid-state polycondensation
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/02—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds
- C08G63/12—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds derived from polycarboxylic acids and polyhydroxy compounds
- C08G63/16—Dicarboxylic acids and dihydroxy compounds
- C08G63/18—Dicarboxylic acids and dihydroxy compounds the acids or hydroxy compounds containing carbocyclic rings
- C08G63/181—Acids containing aromatic rings
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/02—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds
- C08G63/12—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds derived from polycarboxylic acids and polyhydroxy compounds
- C08G63/16—Dicarboxylic acids and dihydroxy compounds
- C08G63/18—Dicarboxylic acids and dihydroxy compounds the acids or hydroxy compounds containing carbocyclic rings
- C08G63/181—Acids containing aromatic rings
- C08G63/183—Terephthalic acids
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/66—Polyesters containing oxygen in the form of ether groups
- C08G63/668—Polyesters containing oxygen in the form of ether groups derived from polycarboxylic acids and polyhydroxy compounds
- C08G63/672—Dicarboxylic acids and dihydroxy compounds
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/62—Plastics recycling; Rubber recycling
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- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Polyesters Or Polycarbonates (AREA)
- Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)
Abstract
The invention discloses a regenerated polyester and a preparation method and application thereof, wherein the method for preparing the regenerated polyester comprises the following steps: (1) mixing a polyester material with alcoholysis liquid containing ethylene glycol and terephthalic acid for alcoholysis reaction to obtain a polyester oligomer melt; (2) removing impurities from the polyester oligomer melt, carrying out polycondensation reaction, discharging, cooling, granulating and drying after the viscosity reaches a preset value, and obtaining polyester chips; (3) and carrying out solid-phase polycondensation on the polyester chip so as to obtain the recycled polyester. Therefore, the regenerated polyester obtained by the method has high transparency and low VOC gas content, and the adopted raw materials are all nontoxic or low-toxicity substances, so that the prepared regenerated polyester is safe and reliable to use.
Description
Technical Field
The invention belongs to the field of materials, and particularly relates to a regenerated polyester, and a preparation method and application thereof.
Background
Polyethylene terephthalate (PET) is a polymer of terephthalic acid or dimethyl terephthalate and ethylene glycol. Due to good physical and chemical stability, processability and the like, the composite material is widely applied to the fields of textile clothing, decoration, food packaging and the like. However, because PET has very strong chemical inertness under natural conditions and is difficult to biodegrade, and a large amount of waste polyester exerts a great pressure on the environment, recycling waste polyester products, realizing effective recycling of resources, and reducing environmental pollution become important subjects of the polyester industry.
The method mainly comprises a physical method and a chemical method for recycling the recycled polyester chips at present, the polyester recycled by the physical method is single and is mainly used in the fields of engineering plastics, recycled fibers and the like, meanwhile, the recycled polyester chips are seriously degraded, the molecular weight is reduced, the viscosity fluctuation is large in the recycling and recycling process, and meanwhile, the acetaldehyde content of the recycled polyester is too high, the color value is poor, and the product cannot be widely used. The chemical regeneration method is mainly regeneration after hydrolysis or alcoholysis, wherein the hydrolysis reaction needs to be carried out under the condition of acid or alkali with higher concentration; in the methanol alcoholysis method, methanol is used for reacting with PET for alcoholysis to generate methyl terephthalate, and then glycol is used for transesterification to generate BHET. Meanwhile, the polyester regenerated by the traditional chemical method has high acetaldehyde content and poor color value, and can only be degraded and used in the field with low requirements on the color value and the acetaldehyde.
Thus, the existing techniques for recycling polyesters are in need of improvement.
Disclosure of Invention
The present invention is directed to solving, at least to some extent, one of the technical problems in the related art. Therefore, the invention aims to provide a regenerated polyester, a preparation method and application thereof, the regenerated polyester obtained by the method has high transparency and low VOC gas content, and the adopted raw materials are all nontoxic or low-toxicity substances, so that the prepared regenerated polyester is safe and reliable to use.
In one aspect of the invention, a process for preparing recycled polyester is provided. According to an embodiment of the invention, the method comprises:
(1) mixing a polyester material with alcoholysis liquid containing ethylene glycol and terephthalic acid for alcoholysis reaction to obtain a polyester oligomer melt;
(2) removing impurities from the polyester oligomer melt, carrying out polycondensation reaction, discharging, cooling, granulating and drying after the viscosity reaches a preset value, and obtaining polyester chips;
(3) and carrying out solid-phase polycondensation on the polyester chip so as to obtain the recycled polyester.
According to the method for preparing the regenerated polyester, the polyester material and the alcoholysis liquid containing the ethylene glycol and the terephthalic acid are mixed for alcoholysis reaction, the polyester material and the ethylene glycol generate ester exchange reaction in the alcoholysis reaction to generate oligomers such as bis-hydroxyethyl terephthalate (BHET), dimer and the like, meanwhile, the terephthalic acid and the ethylene glycol generate esterification reaction to generate similar products, but the polymerization degree of the oligomers is larger, then the polyester chips are obtained by polycondensation reaction after the polyester oligomer melt obtained by the alcoholysis reaction is subjected to impurity removal, finally, the obtained polyester chips are subjected to solid phase polycondensation, the VOC gas in the regenerated polyester can be greatly reduced, the application field of the regenerated polyester is expanded, meanwhile, the raw materials adopted in the whole preparation process are all nontoxic or low-toxic substances, so that the prepared regenerated polyester is safe and reliable to use, and the method is relatively simple, the reaction process is easy to control, and has good popularization and application prospects.
In addition, the method for preparing recycled polyester according to the above embodiment of the present invention may further have the following additional technical features:
in some embodiments of the present invention, in step (1), the polyester material comprises 10 to 60 wt% of the recycled polyester.
In some embodiments of the invention, in the step (1), the mass ratio of the polyester material to the alcoholysis solution is (1-6): (3-20).
In some embodiments of the present invention, in step (1), the polyester material comprises recycled polyester chips and/or a melt obtained by melt-filtering the recycled polyester chips. Thus, the polyester material can be recycled.
In some embodiments of the invention, in the step (1), the molar ratio of the alkyd in the alcoholysis solution is (1-5): 1.
in some embodiments of the present invention, in step (1), the alcoholysis solution further comprises other dihydric alcohol and/or other dibasic acid. Thus, the regularity of the molecular chain of the recycled polyester can be adjusted, and the transparency of the recycled polyester can be improved.
In some embodiments of the invention, the other glycol comprises at least one of isosorbide and neopentyl glycol. Thus, the regularity of the molecular chain of the recycled polyester can be adjusted, and the transparency of the recycled polyester can be improved.
In some embodiments of the invention, the other dihydric alcohol in the alcoholized solution accounts for 1-50% of the total mass of the dihydric alcohol.
In some embodiments of the invention, the other dibasic acid comprises isophthalic acid. Thus, the regularity of the molecular chain of the recycled polyester can be adjusted, and the transparency of the recycled polyester can be improved.
In some embodiments of the invention, the other dibasic acid in the alcoholysis solution accounts for 1-50% of the total mass of the dibasic acid.
In some embodiments of the present invention, in the step (1), the alcoholysis liquid further includes an auxiliary agent including at least one of a catalyst, a stabilizer and a toner.
In some embodiments of the invention, the catalyst comprises at least one of a titanium-containing compound, an antimony-containing compound, and a zinc-containing compound.
In some embodiments of the invention, the catalyst is used in an amount of 50 to 500ppm based on the recycled polyester.
In some embodiments of the invention, the stabilizer comprises at least one of polyphosphoric acid, phosphoric acid, triphenyl phosphate, trimethyl phosphate, and phosphorous acid.
In some embodiments of the invention, the stabilizer is used in an amount of 20 to 250ppm based on the recycled polyester.
In some embodiments of the present disclosure, the toner includes at least one of a phthalocyanine green pigment, an anthraquinone-based pigment, a phthalocyanine blue pigment, a cadmium red-based pigment, and a basic blue dye.
In some embodiments of the present invention, the toner is used in an amount of 10 to 100ppm based on the recycled polyester.
In some embodiments of the invention, in the step (1), the temperature of the alcoholysis reaction is 160-250 ℃, the stirring speed is 20-80 rpm/min, the system pressure is 0.1-0.3 Mpa, and the reaction time is 1-6 hours.
In some embodiments of the invention, in the step (2), the polyester oligomer melt is mixed with the assistant not added in the step (1) after impurity removal, and stirred for 10-20 min, and then the polycondensation reaction is performed in a polycondensation kettle.
In some embodiments of the present invention, in the step (2), the polycondensation reaction is performed under a vacuum condition, the vacuum degree is not higher than 100pa, the reaction temperature is 250-290 ℃, the stirring speed is 10-60 rpm/min, and the reaction time is 1-5 h.
In some embodiments of the present invention, in step (2), the predetermined viscosity is 0.6 to 0.7 dL/g.
In some embodiments of the present invention, in the step (3), the temperature of the solid phase polycondensation reaction is 160-240 ℃ and the time is 6-18 h.
In some embodiments of the invention, in step (3), the recycled polyester has a viscosity of 0.8 to 0.9dL/g, a black and white value of not less than 80, and an acetaldehyde content of less than 1.0 ppm.
In a second aspect of the invention, a recycled polyester is provided. According to the embodiment of the invention, the recycled polyester is prepared by adopting the method. Therefore, the recycled polyester has high transparency and low VOC gas content.
In a third aspect of the invention, a package is provided. According to the embodiment of the invention, the packaging box is prepared by adopting the recycled polyester. Therefore, the packaging box is prepared from the recycled polyester with high transparency and low VOC gas content, and the recycling of polyester materials can be realized while the packaging box cost is reduced.
Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Drawings
The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
FIG. 1 is a schematic flow diagram of a process for making recycled polyester according to one embodiment of the present invention.
Detailed Description
The following detailed description of the embodiments of the present invention is intended to be illustrative, and not to be construed as limiting the invention.
In one aspect of the invention, a process for preparing recycled polyester is provided. According to an embodiment of the invention, with reference to fig. 1, the method comprises:
s100: mixing polyester material with alcoholysis solution containing ethylene glycol and terephthalic acid for alcoholysis reaction
Specifically, the polyester material is a melt obtained by melting and filtering recycled polyester chips and/or recycled polyester chips, the particle size of the recycled polyester chips is 1-30 mm, the recycled polyester chips are subjected to pretreatment including the procedures of sorting, washing, impurity removal, drying and the like in advance, and preferably, the polyester material is a melt obtained by extruding and melting the recycled polyester chips by using a double-screw extruder and then filtering and impurity removal, so that the problem that the polyester chips float on the alcoholysis liquid after the polyester chips are directly added into a reaction kettle can be solved. In the step, a polyester material and an alcoholysis solution containing ethylene glycol and terephthalic acid are mixed for alcoholysis reaction, wherein the temperature of the alcoholysis reaction is 160-250 ℃, the stirring speed is 20-80 rpm/min, the system pressure is 0.1-0.3 Mpa, the reaction time is 1-6 h, the alcoholysis reaction process is shown as formula 1, the polyester material and the ethylene glycol undergo ester exchange reaction to generate oligomers such as bis-hydroxyethyl terephthalate (BHET), dimer and the like, meanwhile, the terephthalic acid and the ethylene glycol undergo esterification reaction to generate similar products, but the polymerization degree of the former is larger, so that a polyester oligomer melt is obtained through the alcoholysis reaction.
Furthermore, the addition amount of the polyester material is 10-60 wt% of the mass of the finally obtained regenerated polyester. The inventor finds that the alcoholysis reaction is faster when the addition amount of the polyester material is too low, and the time required by the process is shorter, and on the contrary, the alcoholysis reaction is longer when the addition amount of the polyester material is too high, because the alcoholysis liquid content is higher when the addition amount of the polyester material is low, the ester exchange reaction can be accelerated, but the recovery rate of the polyester material is reduced, and the alcoholysis liquid content is lower when the addition amount of the polyester material is high, and the ester exchange reaction is slow; meanwhile, when the addition amount of the polyester material is too high, the color value of the regenerated polyester material is reduced to some extent, and the possible reason is that the catalyst contained in the polyester material promotes the occurrence of side reaction and the color-producing substances are increased. Meanwhile, the mass ratio of the polyester chips to the alcoholysis solution is (1-6): (3-20). The inventor finds that the alcoholysis reaction can be carried out faster when the content of the alcoholysis solution is higher; when the content of the alcoholysis solution is low, the alcoholysis reaction is slowly carried out; the reason is that when the content of the alcoholysis solution is high, the content of the dihydric alcohol or the dibasic acid is high, so that the rate of the ester exchange reaction or the acidolysis reaction can be improved, but the recovery rate of the polyester material is reduced, and the load of a vacuum system in a polycondensation stage is increased by the alcohol which does not participate in the reaction; on the contrary, the concentration of the dihydric alcohol or the dibasic acid with lower alcoholysis liquid content is also reduced, and the alcoholysis or acidolysis reaction is slower. And the molar ratio of the alcohol acids in the alcohol hydrolyzed solution is (1-5): 1. the inventor finds that when the molar ratio of the alcohol acid in the alcohol hydrolysate is higher, the ester exchange reaction is faster, and when the molar ratio of the alcohol acid is lower, the esterification and the ester exchange reaction are slower; the reason is that when the molar ratio of the alkyd is higher, the alcohol content is high, which can promote the ester exchange reaction, but when the molar ratio of the alkyd is too high, the addition amount of the dihydric alcohol is larger, and the dihydric alcohol which can not participate in alcoholysis or esterification dissociation can increase the burden of a vacuum system in the polycondensation stage, which is not beneficial to the polycondensation reaction; in contrast, when the molar ratio of the alkyd is low, the alcohol content is low and the transesterification reaction proceeds slowly.
Further, in order to reduce the regularity of a molecular chain of a polyester oligomer melt and improve the transparency of the finally regenerated polyester, the alcoholysis liquid adopted in the method further comprises other dihydric alcohol and/or other dibasic acid, wherein the other dihydric alcohol comprises at least one of propylene glycol, isosorbide and neopentyl glycol, the other dibasic acid comprises isophthalic acid, the other dihydric alcohol in the alcoholysis liquid accounts for 1-50% of the total mass of the dihydric alcohol, and the other dibasic acid in the alcoholysis liquid accounts for 1-60% of the total mass of the dibasic acid. The inventor finds that if the proportion of other dibasic acid to other dihydric alcohol is too low, namely the addition amount of ethylene glycol and terephthalic acid in the alcoholysis solution is too high, the regenerated polyester is easy to crystallize in the processing process, and the product is fogged; the reason for this is that the addition of ethylene glycol and terephthalic acid is too high, the molecular chain regularity is good, and the semicrystallization time is very short; if the proportion of other dibasic acids to other dihydric alcohols is too high, namely the addition amount of the glycol and the terephthalic acid is low, the addition amount of other types of dibasic acids and/or dihydric alcohols is increased, the molecular chain regularity is reduced, the semi-crystallization time is prolonged, and the improvement of the transparency is facilitated.
According to one embodiment of the invention, neopentyl glycol is further added into the alcoholysis solution as an example, the reaction process is shown as formula 2, the polyester material, ethylene glycol and neopentyl glycol are subjected to ester exchange reaction to generate oligomer, and meanwhile, terephthalic acid, ethylene glycol and neopentyl glycol are subjected to esterification reaction to generate similar products, the polymerization degree of the polyester material is larger, and the neopentyl glycol is introduced into a molecular chain to effectively reduce the regularity of the molecular chain, reduce the crystallinity and improve the transparency; and the crystallization performance of the neopentyl glycol in the recycled polyester can be effectively regulated and controlled by adjusting the content of the neopentyl glycol in the recycled polyester, so that the transparency of the recycled polyester is improved.
According to another embodiment of the invention, taking the case that isophthalic acid is further added into the alcoholysis solution as an example, during the alcoholysis reaction, the polyester material and ethylene glycol generate ester exchange reaction to generate oligomer, and meanwhile, terephthalic acid, isophthalic acid and ethylene glycol generate esterification reaction to produce similar products, wherein the polymerization degree of the polyester material is larger, and the regularity of a molecular chain can be effectively reduced by introducing isophthalic acid into the molecular chain, so that the crystallinity of the molecular chain is reduced, and the transparency of the molecular chain is improved; and the crystallization performance of the regenerated polyester can be effectively regulated and controlled by regulating the content of the isophthalic acid in the regenerated polyester, so that the transparency of the regenerated polyester is regulated. Meanwhile, the introduction of the third monomer has other synergistic effects, for example, the introduced isophthalic acid not only improves the transparency as the third monomer, but also plays a role in promoting the acid hydrolysis of the recovered polyester chips and the esterification reaction of alcohol and acid because the isophthalic acid is easier to ionize hydrogen ions than the phthalic acid.
According to another embodiment of the invention, taking the case that isophthalic acid and neopentyl glycol are further added into the alcoholysis solution as an example, during the alcoholysis reaction, the polyester material, ethylene glycol and neopentyl glycol undergo an ester exchange reaction to generate oligomers, and meanwhile, terephthalic acid, isophthalic acid, ethylene glycol and neopentyl glycol undergo an esterification reaction, and by introducing isophthalic acid and neopentyl glycol into a molecular chain, the regularity of the original molecular chain can be more effectively reduced, the crystallinity of the molecular chain is reduced, and the transparency of the molecular chain is improved; the crystallization performance of the recycled polyester can be effectively regulated and controlled by regulating the contents of the isophthalic acid and the neopentyl glycol in the recycled polyester, so that the transparency of the recycled polyester is regulated; meanwhile, as isophthalic acid is easier to ionize hydrogen ions than terephthalic acid, the method also plays a role in promoting alcoholysis of the recycled polyester chips and promoting esterification reaction of alcohol and acid, and is more advantageous to a certain extent.
In addition, the alcoholic liquor further comprises an auxiliary agent, and the auxiliary agent comprises at least one of a catalyst, a stabilizer and a toner, wherein the catalyst comprises at least one of a titanium-containing compound, an antimony-containing compound and a zinc-containing compound; the stabilizer comprises at least one of polyphosphoric acid, phosphoric acid, triphenyl phosphate, trimethyl phosphate and phosphorous acid; the toner comprises at least one of phthalocyanine green pigment, anthraquinone pigment, phthalocyanine blue pigment, cadmium red pigment and basic blue dye, wherein the using amount of the catalyst accounts for 50-500 ppm of the finally obtained regenerated polyester, the using amount of the stabilizer accounts for 20-250 ppm of the finally obtained regenerated polyester, and the using amount of the toner accounts for 5-100 ppm of the finally obtained regenerated polyester. The inventor finds that when the using amount of the catalyst is lower, the number of catalytic sites is less, and the reaction time is longer; when the catalyst is used in a high amount, the polymerization reaction is promoted, the generation of side reaction is accelerated, and the color value of the product is deteriorated.
S200: removing impurities from the polyester oligomer melt, performing polycondensation reaction, discharging, cooling, granulating and drying after the viscosity reaches a preset value
In the step, the obtained polyester oligomer melt is subjected to impurity removal through a melt filter and then subjected to polycondensation reaction, wherein the polycondensation reaction is as shown in formula 3 (only ethylene glycol is added to alcoholysis liquid) and formula 4 (ethylene glycol and neopentyl glycol are added to the alcoholysis liquid), the process is carried out in a vacuum state, the vacuum degree is not higher than 100pa, the reaction temperature is 250-290 ℃, the stirring speed is 10-60 rpm/min, the reaction time is 1-5 h, and after the preset viscosity of 0.6-0.7 dL/g is reached, polyester chips are obtained through belt head discharging, water cooling, grain cutting and drying, wherein the belt head needs to be preheated before grain cutting. It should be noted that, the size of the polyester chip can be selected by those skilled in the art according to actual needs.
Further, after removing impurities from the obtained polyester oligomer melt, mixing the polyester oligomer melt with the assistant not added in the step S100, stirring for 10-20 min, and then carrying out the polycondensation reaction in a polycondensation kettle.
S300: solid phase polycondensation is carried out on polyester chips
In the step, the polyester slices are subjected to solid phase polycondensation at 160-240 ℃ for 6-18 h to improve the viscosity of the regenerated polyester and remove VOC gas, so that the regenerated polyester with the viscosity of 0.8-0.9 dL/g, the L value of not less than 80 and the acetaldehyde content of less than 1.0ppm is obtained. Specifically, the original micromolecule by-product in the polyester chip and the micromolecule by-product generated in the solid phase polycondensation process are brought out by a vacuum system or inert gas purging.
According to the method for preparing the regenerated polyester, the polyester material and the alcoholysis liquid containing the ethylene glycol and the terephthalic acid are mixed for alcoholysis reaction, the polyester material and the ethylene glycol generate ester exchange reaction in the alcoholysis reaction to generate oligomers such as bis-hydroxyethyl terephthalate (BHET), dimer and the like, meanwhile, the terephthalic acid and the ethylene glycol generate esterification reaction to generate similar products, but the polymerization degree of the oligomers is larger, then the polyester chips are obtained by polycondensation reaction after the polyester oligomer melt obtained by the alcoholysis reaction is subjected to impurity removal, finally, the obtained polyester chips are subjected to solid phase polycondensation, the VOC gas in the regenerated polyester can be greatly reduced, the application field of the regenerated polyester is expanded, meanwhile, the raw materials adopted in the whole preparation process are all nontoxic or low-toxic substances, so that the prepared regenerated polyester is safe and reliable to use, and the method is relatively simple, the reaction process is easy to control, and has good popularization and application prospects. The viscosity of the regenerated polyester obtained by the method is 0.8-0.9 dL/g, the black-white value is not lower than 80, and the acetaldehyde content is lower than 1.0 ppm.
In a second aspect of the invention, a recycled polyester is provided. According to the embodiment of the invention, the recycled polyester is prepared by adopting the method. Therefore, the recycled polyester has high transparency and low VOC gas content. It should be noted that the features and advantages described above for the process for preparing recycled polyester apply equally to the recycled polyester and are not described in further detail here.
In a third aspect of the invention, a package is provided. According to the embodiment of the invention, the packaging box is prepared by adopting the recycled polyester. Therefore, the packaging box is prepared from the recycled polyester with high transparency and low VOC gas content, and the recycling of polyester materials can be realized while the packaging box cost is reduced. It should be noted that the features and advantages described above for the recycled polyester and the preparation method thereof are also applicable to the preparation of the packaging box, and are not described herein again.
The following embodiments of the present invention are described in detail, and it should be noted that the following embodiments are exemplary only, and are not to be construed as limiting the present invention. In addition, all reagents used in the following examples are commercially available or can be synthesized according to methods herein or known, and are readily available to those skilled in the art for reaction conditions not listed, if not explicitly stated.
Example 1
(1) Mixing terephthalic acid, ethylene glycol, a catalyst (ethylene glycol antimony accounting for 300ppm of the finally regenerated polyester) and a stabilizer (phosphoric acid accounting for 50ppm of the finally regenerated polyester) to prepare an alcoholysis solution, introducing the alcoholysis solution into a reaction kettle, wherein the molar ratio of the terephthalic acid to the ethylene glycol is 1:1.8, adding recovered polyester chips into the reaction kettle (the recovered polyester chips account for 25% of the finally regenerated polyester), wherein the mass ratio of the recovered polyester chips to the alcoholysis solution is 23: 100, simultaneously controlling the temperature of the reaction kettle to be 230-240 ℃, the stirring speed to be 60rpm, the system pressure to be 0.20-0.3 Mpa, carrying out esterification and alcoholysis, finishing the reaction when distilled water is close to a theoretical value, and reacting for about 4 hours to obtain a polyester oligomer melt;
(2) filtering the esterified oligomer melt through a melt filter, introducing the esterified oligomer melt into a polycondensation kettle, adding toner (anthraquinone pigment, 5ppm), stirring for 10min, controlling the reaction temperature to be 260-265 ℃, opening a vacuum system to start polycondensation reaction, finally keeping the vacuum degree lower than 100pa, opening a heat source of a casting head 20min before the viscosity reaches an expected value, heating the casting head, stopping stirring after the viscosity reaches about 0.62dL/g, discharging, cooling with water, granulating and drying to obtain polyester chips;
(3) and (3) tackifying the polyester chips through solid-phase polycondensation, controlling the temperature to be 200-240 ℃ and the time to be 12h, removing VOC gas, and obtaining the regenerated polyester after finishing.
Example 2
(1) Mixing terephthalic acid, ethylene glycol, neopentyl glycol, a catalyst (ethylene glycol antimony accounting for 30ppm of the finally regenerated polyester), a stabilizer (triphenyl phosphate accounting for 60ppm of the finally regenerated polyester) and a toner (anthraquinone pigment accounting for 8ppm of the finally regenerated polyester) to prepare an alcoholic solution, introducing the alcoholic solution into a reaction kettle, wherein the molar ratio of the ethylene glycol to the neopentyl glycol is 4:1, the molar ratio of the alkyd is 2:1, the temperature of the reaction kettle is set to be 220-230 ℃, and when the temperature reaches a set temperature, introducing a recovered polyester melt subjected to double-screw melting filtration into the reaction kettle (the mass ratio of the recovered polyester chips to the alcoholic solution is 25 percent of the mass of the finally regenerated polyester), wherein the mass ratio of the recovered polyester chips to the alcoholic solution is 11: 50, simultaneously controlling the stirring speed to be 60rpm and the system pressure to be 0.25-0.3 Mpa, carrying out esterification and alcoholysis, finishing the reaction when the distilled water is close to the theoretical value, and reacting for about 3 hours to obtain a polyester oligomer melt;
(2) filtering the esterified oligomer melt through a melt filter, introducing the esterified oligomer melt into a polycondensation kettle, controlling the reaction temperature to be between 260 and 275 ℃, opening a vacuum system to start polycondensation, finally keeping the vacuum degree lower than 100pa, opening a heat source of a casting head 20min before the viscosity reaches an expected value, heating the casting head until the viscosity reaches about 0.62dL/g, stopping stirring, discharging, cooling with water, pelletizing and drying to obtain polyester chips;
(3) and (3) tackifying the polyester chips through solid-phase polycondensation, controlling the temperature to be 200-220 ℃ and the time to be 12h, removing VOC gas, and obtaining the regenerated polyester after finishing.
Example 3
The procedure for the preparation of recycled polyester was the same as in example 2 except that neopentyl glycol was added in an amount of 5% by weight based on the total amount of the dihydric alcohol.
Example 4
The procedure for the preparation of recycled polyester was the same as in example 2 except that neopentyl glycol was added in an amount of 25% by weight based on the total amount of the dihydric alcohol.
Example 5
The procedure for the preparation of recycled polyester was the same as in example 2 except that neopentyl glycol was added in an amount of 1% by weight based on the total amount of the dihydric alcohol.
Example 6
The procedure for the preparation of recycled polyester was the same as in example 2 except that neopentyl glycol was added in an amount of 30% by weight based on the total amount of the dihydric alcohol.
Example 7
The procedure for the preparation of recycled polyester was the same as in example 2 except that neopentyl glycol was added in an amount of 40% by weight based on the total amount of the dihydric alcohol.
Example 8
The procedure for the preparation of recycled polyester was the same as in example 2 except that neopentyl glycol was added in an amount of 50% by weight based on the total amount of the dihydric alcohol.
Example 9
The procedure for the preparation of recycled polyester was the same as in example 2 except that neopentyl glycol was replaced by isosorbide.
Example 10
(1) Mixing terephthalic acid, isophthalic acid, ethylene glycol, a catalyst (ethylene glycol antimony which accounts for 320ppm of the finally regenerated polyester) and a stabilizer (triphenyl phosphate which accounts for 50ppm of the finally regenerated polyester) to prepare an alcoholysis solution, introducing the alcoholysis solution into a reaction kettle, wherein the molar ratio of the terephthalic acid to the isophthalic acid is 9:1, and the molar ratio of the alkyd is 1.8:1, adding recovered polyester chips into the reaction kettle (the recovered polyester chips account for 25% of the finally regenerated polyester), controlling the temperature of the reaction kettle to be 240-250 ℃, stirring speed to be 65rpm, system pressure to be 0.20-0.25 MPa, carrying out esterification and alcoholysis under the conditions that the reaction is finished when distilled water is close to a theoretical value, and reacting for about 2.5 hours to obtain a polyester oligomer melt;
(2) filtering the esterified oligomer melt through a melt filter, introducing the esterified oligomer melt into a polycondensation kettle, adding toner (anthraquinone, 10ppm), stirring for 10min, controlling the reaction temperature to be 260-270 ℃, opening a vacuum system to start polycondensation reaction, finally keeping the vacuum degree lower than 100pa, opening a heat source of a casting head 20min before the viscosity reaches an expected value, heating the casting head, stopping stirring after the viscosity reaches 0.6dL/g, discharging, water cooling, granulating and drying to obtain polyester chips;
(3) and (3) tackifying the polyester chips through solid-phase polycondensation, controlling the temperature to be 200-220 ℃ and the time to be 12h, removing VOC gas, and obtaining the regenerated polyester after finishing.
Example 11
The procedure for preparing a recycled polyester was the same as in example 10 except that isophthalic acid was added in an amount of 5 wt% based on the total amount of the dibasic acids.
Example 12
The procedure for preparing a recycled polyester was the same as in example 10 except that isophthalic acid was added in an amount of 35 wt% based on the total amount of the dibasic acids.
Example 13
The procedure for producing a recycled polyester was the same as in example 10 except that isophthalic acid was added in an amount of 45 wt% based on the total amount of the dibasic acids.
Example 14
The procedure for preparing a recycled polyester was the same as in example 10 except that isophthalic acid was added in an amount of 50 wt% based on the total amount of the dibasic acids.
Example 15
The procedure for preparing a recycled polyester was the same as in example 10 except that isophthalic acid was added in an amount of 1 wt% based on the total amount of the dibasic acids.
Example 16
(1) Terephthalic acid, isophthalic acid, neopentyl glycol, ethylene glycol, a catalyst (ethylene glycol antimony which accounts for 250ppm of the finally regenerated polyester), a stabilizer (phosphoric acid which accounts for 40ppm of the finally regenerated polyester) and a toner (anthraquinone which accounts for 10ppm of the finally regenerated polyester) are mixed to prepare an alcoholysis solution which is introduced into a reaction kettle, wherein the molar ratio of ethylene glycol to neopentyl glycol is 9:1, the molar ratio of terephthalic acid to isophthalic acid is 9:1, and the molar ratio of alkyd is 1.8:1, and then recovered polyester chips are added into the reaction kettle (the mass ratio of the recovered polyester chips to the alcoholysis solution is 5: 22, simultaneously controlling the temperature of the reaction kettle to be 235-250 ℃, the stirring speed to be 65rpm, the system pressure to be 0.25-0.30 Mpa, carrying out esterification and alcoholysis, finishing the reaction when distilled water is close to a theoretical value, and reacting for about 3 hours to obtain a polyester oligomer melt;
(2) filtering the esterified oligomer melt through a melt filter, introducing the esterified oligomer melt into a polycondensation kettle, controlling the reaction temperature to be between 260 and 275 ℃, opening a vacuum system to start polycondensation, finally keeping the vacuum degree lower than 100pa, opening a heat source of a casting head 20min before the viscosity reaches an expected value, heating the casting head until the viscosity reaches 0.6dL/g, stopping stirring, discharging, cooling with water, cutting into granules and drying to obtain polyester chips;
(3) and (3) tackifying the polyester chips through solid-phase polycondensation, controlling the temperature to be 180-200 ℃ and the time to be 8h, removing VOC gas, and obtaining the regenerated polyester after finishing.
Example 17
The procedure for the preparation of recycled polyester was the same as in example 16 except that isophthalic acid was added in an amount of 5 wt% based on the total amount of the dibasic acid and neopentyl glycol was added in an amount of 5 wt% based on the weight of the dibasic alcohol.
Example 18
The procedure for preparing a recycled polyester was the same as in example 16 except that isophthalic acid was added in an amount of 35 wt% based on the total amount of the dibasic acid and neopentyl glycol was added in an amount of 30 wt% based on the weight of the dibasic alcohol.
Example 19
The procedure for the preparation of recycled polyester was the same as in example 16 except that neopentyl glycol was replaced by isosorbide and the amount of added isophthalic acid was 40 wt% based on the total amount of dibasic acids and the amount of added isosorbide was 20 wt% based on the weight of the dibasic alcohol.
Example 20
The procedure for the preparation of recycled polyester was the same as in example 16 except that neopentyl glycol was replaced by isosorbide and the amount of added isophthalic acid was 20 wt% based on the total amount of dibasic acids and the amount of added isosorbide was 40 wt% based on the weight of the dibasic alcohol.
Example 21
The procedure for the preparation of recycled polyester was the same as in example 16 except that neopentyl glycol was replaced by isosorbide and the amount of added isophthalic acid was 30% by weight of the total amount of dibasic acids and the amount of added isosorbide was 45% by weight of the dibasic alcohols.
The recycled polyesters obtained in examples 1 to 21 were evaluated for viscosity, acetaldehyde content and color, and the evaluation data are shown in Table 1.
TABLE 1 evaluation data for viscosity, acetaldehyde content and color of recycled polyesters obtained in examples 1 to 21
In the description of the specification, reference to the description of "one embodiment," "some embodiments," "an example," "a specific example," or "some examples" or the like means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Although embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are exemplary and not to be construed as limiting the present invention, and that changes, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.
Claims (15)
1. A method of making recycled polyester, comprising:
(1) mixing a polyester material with alcoholysis liquid containing ethylene glycol and terephthalic acid for alcoholysis reaction to obtain a polyester oligomer melt;
(2) removing impurities from the polyester oligomer melt, carrying out polycondensation reaction, discharging, cooling, granulating and drying after the viscosity reaches a preset value to obtain polyester chips;
(3) and carrying out solid-phase polycondensation on the polyester chip so as to obtain the recycled polyester.
2. The method according to claim 1, wherein in step (1), the polyester material accounts for 10 to 60 wt% of the recycled polyester.
3. The method according to claim 1 or 2, wherein in the step (1), the mass ratio of the polyester material to the alcoholysis solution is (1-6): (3-20).
4. The method according to claim 1, wherein in step (1), the polyester material comprises recycled polyester chips and/or a melt obtained by melt-filtering the recycled polyester chips.
5. The method according to claim 1, wherein in the step (1), the molar ratio of the alkyd acids in the alcoholysis solution is (1-5): 1.
6. the method as claimed in claim 5, wherein, in step (1), the alcoholized solution further comprises other dihydric alcohol and/or other dibasic acid;
optionally, the other glycol comprises at least one of isosorbide and neopentyl glycol;
optionally, the other dihydric alcohols in the alcoholized solution account for 1-50% of the total mass of the dihydric alcohols;
optionally, the other dibasic acid comprises isophthalic acid;
optionally, the alcoholic hydrolysate accounts for 1-50% of the total mass of the dibasic acid relative to the other dibasic acid.
7. The method according to claim 1 or 6, wherein in step (1), the alcoholysis liquid further comprises an auxiliary agent, the auxiliary agent comprising at least one of a catalyst, a stabilizer and a toner;
optionally, the catalyst comprises at least one of a titanium-containing compound, an antimony-containing compound, and a zinc-containing compound;
optionally, the amount of the catalyst accounts for 50-500 ppm of the regenerated polyester;
optionally, the stabilizer comprises at least one of polyphosphoric acid, phosphoric acid, triphenyl phosphate, trimethyl phosphate, and phosphorous acid;
optionally, the dosage of the stabilizer accounts for 20-250 ppm of the regenerated polyester;
optionally, the toner includes at least one of phthalocyanine green pigment, anthraquinone-based pigment, phthalocyanine blue pigment, cadmium red-based pigment, and basic blue dye;
optionally, the amount of the toner is 5-100 ppm of the recycled polyester.
8. The method of claim 1, wherein in the step (1), the temperature of the alcoholysis reaction is 160-250 ℃, the stirring speed is 20-80 rpm/min, the system pressure is 0.1-0.3 MPa, and the reaction time is 1-6 h.
9. The method according to claim 7, wherein in the step (2), the polyester oligomer melt is mixed with the auxiliary agent which is not added in the step (1) for 10-20 min after impurity removal, and then the polycondensation reaction is carried out in a polycondensation kettle.
10. The method according to claim 9, wherein in the step (2), the polycondensation reaction is performed under vacuum, the vacuum degree is not higher than 100pa, the reaction temperature is 250-290 ℃, the stirring speed is 10-60 rpm/min, and the reaction time is 1-5 h.
11. The method according to claim 1, wherein in step (2), the predetermined viscosity is 0.6 to 0.7 dL/g.
12. The method according to claim 1, wherein in the step (3), the temperature of the solid phase polycondensation reaction is 160 to 240 ℃ and the time is 6 to 18 hours.
13. The process of claim 1, wherein in step (3), the recycled polyester has a viscosity of 0.8 to 0.9dL/g, a black and white value of not less than 80, and an acetaldehyde content of less than 1.0 ppm.
14. A recycled polyester, characterized in that it is obtained by the process according to any one of claims 1 to 13.
15. A package made from the recycled polyester of claim 14.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115160549A (en) * | 2022-08-26 | 2022-10-11 | 华润化学材料科技股份有限公司 | Production method for recycling and continuously operating polyester chips |
| CN115340666A (en) * | 2022-08-10 | 2022-11-15 | 华润化学材料科技股份有限公司 | Hydroxyl-terminated hyperbranched polymer and preparation method and application thereof |
| CN115449066A (en) * | 2022-10-18 | 2022-12-09 | 浙江理工大学 | Preparation method of low-melting-point high-shrinkage type recycled polyester |
| CN116284710A (en) * | 2023-05-22 | 2023-06-23 | 广东绿王新材料有限公司 | Method for preparing polyester chips by chemical recycling of waste polyester fibers |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003160655A (en) * | 2001-11-28 | 2003-06-03 | Teijin Ltd | Method for producing polyester, and polyester fiber |
| CN102585182A (en) * | 2012-01-10 | 2012-07-18 | 金发科技股份有限公司 | Method for preparing amorphous copolyester by post-consumer polyester |
| CN111138641A (en) * | 2018-11-02 | 2020-05-12 | 中国石油化工股份有限公司 | Method for preparing bottle-grade slices by recycling waste polyester bottles |
| CN111849026A (en) * | 2020-08-27 | 2020-10-30 | 华润化学材料科技股份有限公司 | Method and system for producing rPET bottle grade polyester chip |
-
2020
- 2020-11-23 CN CN202011322930.0A patent/CN114524924A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003160655A (en) * | 2001-11-28 | 2003-06-03 | Teijin Ltd | Method for producing polyester, and polyester fiber |
| CN102585182A (en) * | 2012-01-10 | 2012-07-18 | 金发科技股份有限公司 | Method for preparing amorphous copolyester by post-consumer polyester |
| CN111138641A (en) * | 2018-11-02 | 2020-05-12 | 中国石油化工股份有限公司 | Method for preparing bottle-grade slices by recycling waste polyester bottles |
| CN111849026A (en) * | 2020-08-27 | 2020-10-30 | 华润化学材料科技股份有限公司 | Method and system for producing rPET bottle grade polyester chip |
Non-Patent Citations (1)
| Title |
|---|
| 叶铁林: "《化工结晶过程原理及应用》", vol. 3, 北京工业大学出版社, pages: 379 * |
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| CN115340666A (en) * | 2022-08-10 | 2022-11-15 | 华润化学材料科技股份有限公司 | Hydroxyl-terminated hyperbranched polymer and preparation method and application thereof |
| CN115160549A (en) * | 2022-08-26 | 2022-10-11 | 华润化学材料科技股份有限公司 | Production method for recycling and continuously operating polyester chips |
| CN115449066A (en) * | 2022-10-18 | 2022-12-09 | 浙江理工大学 | Preparation method of low-melting-point high-shrinkage type recycled polyester |
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| CN116284710A (en) * | 2023-05-22 | 2023-06-23 | 广东绿王新材料有限公司 | Method for preparing polyester chips by chemical recycling of waste polyester fibers |
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