CN110606943A - Method for preparing water-soluble polyester from waste PETG - Google Patents
Method for preparing water-soluble polyester from waste PETG Download PDFInfo
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- CN110606943A CN110606943A CN201910864623.6A CN201910864623A CN110606943A CN 110606943 A CN110606943 A CN 110606943A CN 201910864623 A CN201910864623 A CN 201910864623A CN 110606943 A CN110606943 A CN 110606943A
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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
- C08G63/66—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
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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
- C08G63/68—Polyesters containing atoms other than carbon, hydrogen and oxygen
- C08G63/688—Polyesters containing atoms other than carbon, hydrogen and oxygen containing sulfur
- C08G63/6884—Polyesters containing atoms other than carbon, hydrogen and oxygen containing sulfur derived from polycarboxylic acids and polyhydroxy compounds
- C08G63/6886—Dicarboxylic acids and dihydroxy compounds
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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
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J11/00—Recovery or working-up of waste materials
- C08J11/04—Recovery or working-up of waste materials of polymers
- C08J11/10—Recovery or working-up of waste materials of polymers by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation
- C08J11/18—Recovery or working-up of waste materials of polymers by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation by treatment with organic material
- C08J11/22—Recovery or working-up of waste materials of polymers by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation by treatment with organic material by treatment with organic oxygen-containing compounds
- C08J11/24—Recovery or working-up of waste materials of polymers by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation by treatment with organic material by treatment with organic oxygen-containing compounds containing hydroxyl groups
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2367/00—Characterised by the use of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Derivatives of such polymers
- C08J2367/02—Polyesters derived from dicarboxylic acids and dihydroxy compounds
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- 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)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)
Abstract
The invention discloses a method for preparing water-soluble polyester by waste PETG, which is characterized by comprising the following steps: the preparation method comprises the following preparation steps: (1) depolymerizing PETG; (2) and (4) carrying out polymerization reaction. The waste PETG product is used as a raw material, the cost is low, and the alcoholysis main catalyst and the synergistic auxiliary catalyst are compounded for use, so that the energy consumption is reduced; in the synthesis process of the water-soluble polyester, polyether modification is added to increase the water solubility of the polyester, the polyester can be completely dissolved after being stirred in hot water at 90 ℃ for 20 minutes, the catalyst used in the polycondensation reaction is an antimony-free environment-friendly catalyst, the whole reaction process is carried out in a reaction kettle, the operation is simple, and industrialization is easy to realize.
Description
Technical Field
The invention relates to the technical field of waste PETG recovery, in particular to a method for preparing water-soluble polyester by waste PETG.
Background
China is a large plastic consumption country, and with the development of the PETG polyester industry in recent years, PETG is applied to the fields of bottle flakes, shrink films, packaging films, plates and the like due to excellent mechanical, optical and processing properties and reasonable price, and a large amount of waste PETG needs to be recycled every year.
At present, two main methods for recovering and treating waste PETG are provided: including physical recovery and chemical recovery. The physical recovery mainly comprises the steps of simply separating, cleaning, melting and granulating the polyester and the polyester products to obtain secondary plastic products, wherein although the process is simple and convenient and the cost is low, the viscosity of the obtained products is low, the performance is reduced, and the secondary plastic cannot be recovered again, so that the aim of recycling is not achieved; chemical recovery is mainly to depolymerize polymers into small molecules and oligomers by a chemical method, and obtain intermediates after separation and purification, so that the chemical recovery treatment method is more and more emphasized at present.
Disclosure of Invention
The invention provides a method for preparing water-soluble polyester by waste PETG, which aims to: the method is simple to operate, low in energy consumption and easy to realize industrialization, and the waste PETG is depolymerized to prepare the high-performance water-soluble polyester.
The technical solution of the invention is as follows:
a method for preparing water-soluble polyester by waste PETG is characterized by comprising the following steps: the preparation method comprises the following preparation steps:
(1) performing PETG depolymerization, namely crushing the waste PETG polyester product by a crusher, washing and drying the crushed product to obtain pretreated PETG, adding 100 parts by weight of the treated PETG polyester, 0.1-0.5 part by weight of alcoholysis catalyst, 0.01-0.05 part by weight of auxiliary catalyst and 80 ~ 150 parts by weight of dihydric alcohol into a reaction kettle, introducing nitrogen, starting condensed water to reflux, heating to 185-197 ℃, starting stirring, preserving heat and refluxing for 0.5-4 h, and finishing reaction to obtain a product after alcoholysis;
(2) polymerization reaction: adding 5-30 parts of polyether, 10-30 parts of isophthalic acid-5-sulfonate or isophthalic acid-5-sulfonate derivative, 0.1-0.6 part of polycondensation catalyst and 0.1-0.8 part of stabilizer into the reaction kettle, keeping the temperature, stirring for 20-40 minutes, heating to 250-260 ℃, vacuumizing to 100-200 Pa, and keeping the temperature for 1-2 hours; and continuously heating to 265-270 ℃, vacuumizing to 20-40 Pa, preserving heat for 1-2 h, and air-cooling and granulating to obtain the water-soluble polyester W-PETG.
The waste polyester product in the step (1) is one or more than two of PETG bottle sheets, films and sheets.
The alcoholysis catalyst in the step (1) is one of zinc acetate, basic zinc acetate and sodium carbonate.
The auxiliary catalyst in the step (1) is sodium ethylene glycol.
In the step (1), the dihydric alcohol is one or two of ethylene glycol and propylene glycol.
In the step (1), the alcoholysis catalyst and the auxiliary catalyst are prepared into 10-18% by mass of ethylene glycol or propylene glycol solution and added into the reaction kettle.
And in the step (2), the polyether is one or two of polyethylene glycol and polypropylene glycol.
The isophthalic acid-5-sulfonate in the step (2) is isophthalic acid-5-sodium sulfonate, and the isophthalic acid-5-sulfonate derivative is one of dimethyl isophthalate-5-sodium sulfonate and dihydroxy ethyl isophthalate-5-sodium sulfonate.
And (3) the stabilizer in the step (2) is one or more than two of dimethyl phosphate, trimethyl phosphate, dimethyl phosphite and trimethyl phosphite.
And (3) preparing 10-18% by mass of ethylene glycol or propylene glycol solution from the isophthalic acid-5-sulfonate or the isophthalic acid-5-sulfonate derivative, a polycondensation catalyst and a stabilizer in the step (2) and adding the ethylene glycol or the propylene glycol solution into a reaction kettle.
The invention has the technical effects that: the waste PETG product is used as a raw material, the cost is low, and the alcoholysis main catalyst and the synergistic auxiliary catalyst are compounded for use, so that the energy consumption is reduced; in the synthesis process of the water-soluble polyester, polyether modification is added to increase the water solubility of the polyester, the polyester can be completely dissolved after being stirred in hot water at 90 ℃ for 20 minutes, the catalyst used in the polycondensation reaction is an antimony-free environment-friendly catalyst, the whole reaction process is carried out in a reaction kettle, the operation is simple, and industrialization is easy to realize.
Detailed Description
The invention will be further elucidated with reference to the following specific examples, which are intended to provide a better understanding of the present invention, and therefore do not affect the scope of the invention.
Example 1
(1) Depolymerization of PETG: crushing the waste PETG polyester product by a crusher, washing and drying the crushed waste PETG polyester product to obtain pretreated PETG, adding 100 parts by weight of the treated PETG polyester, 0.2 part by weight of zinc acetate, 0.02 part by weight of an auxiliary catalyst sodium glycol and 100 parts by weight of glycol into a reaction kettle, introducing nitrogen, starting condensed water for refluxing, heating to 190 ℃, starting stirring, preserving heat and refluxing for 2 hours, and finishing the reaction to obtain a product after alcoholysis;
(2) polymerization reaction: adding 15 parts of polyethylene glycol, 20 parts of sodium 5-sulfoisophthalate, 0.3 part of titanium glycol serving as a polycondensation catalyst, 0.2 part of trimethyl phosphate and 0.2 part of trimethyl phosphite into the reaction kettle, keeping the temperature, stirring for 30 minutes, heating to 255 ℃, vacuumizing at 100-200 Pa, and keeping the temperature for 2 hours; and continuously heating to 270 ℃, vacuumizing at 20-40 Pa, preserving heat for 2h, and air-cooling and granulating to obtain the water-soluble polyester W1-PETG.
The obtained W1-PETG can be completely dissolved only in 32 minutes by stirring in hot water at 90 ℃.
Example 2
(1) Depolymerization of PETG: crushing the waste PETG polyester product by a crusher, washing and drying the crushed waste PETG polyester product to obtain pretreated PETG, adding 100 parts by weight of the treated PETG polyester, 0.2 part by weight of zinc acetate, 0.02 part by weight of an auxiliary catalyst sodium glycol and 100 parts by weight of glycol into a reaction kettle, introducing nitrogen, starting condensed water for refluxing, heating to 190 ℃, starting stirring, preserving heat and refluxing for 2 hours, and finishing the reaction to obtain a product after alcoholysis;
(2) polymerization reaction: adding 25 parts of polyethylene glycol, 20 parts of sodium 5-sulfoisophthalate, 0.3 part of titanium glycol serving as a polycondensation catalyst, 0.2 part of trimethyl phosphate and 0.2 part of trimethyl phosphite into the reaction kettle, keeping the temperature, stirring for 30 minutes, heating to 255 ℃, vacuumizing at 100-200 Pa, and keeping the temperature for 2 hours; and continuously heating to 270 ℃, vacuumizing at 20-40 Pa, preserving heat for 2h, and air-cooling and granulating to obtain the water-soluble polyester W2-PETG.
The obtained W2-PETG is stirred in hot water at 90 ℃ and can be completely dissolved in 30 minutes.
Example 3
(1) Depolymerization of PETG: crushing the waste PETG polyester product by a crusher, washing and drying the crushed waste PETG polyester product to obtain pretreated PETG, adding 100 parts by weight of the treated PETG polyester, 0.3 part by weight of zinc acetate, 0.03 part by weight of an auxiliary catalyst sodium glycol and 100 parts by weight of glycol into a reaction kettle, introducing nitrogen, starting condensed water for refluxing, heating to 185 ℃, starting stirring, preserving heat and refluxing for 1h, and finishing the reaction to obtain a product after alcoholysis;
(2) polymerization reaction: adding 25 parts of polyethylene glycol, 25 parts of 5-sodium sulfoisophthalate, 0.3 part of titanium glycol serving as a polycondensation catalyst, 0.2 part of trimethyl phosphate and 0.2 part of trimethyl phosphite into the reaction kettle, keeping the temperature, stirring for 30 minutes, heating to 255 ℃, vacuumizing at 100-200 Pa, and keeping the temperature for 2 hours; and heating to 270 ℃, vacuumizing at 20-40 Pa, preserving heat for 2h, and air-cooling and granulating to obtain the water-soluble polyester W3-PETG.
The obtained W3-PETG is stirred in hot water at 90 ℃ and can be completely dissolved in 28 minutes.
Example 4
(1) Depolymerization of PETG: crushing the waste PETG polyester product by a crusher, washing and drying the crushed waste PETG polyester product to obtain pretreated PETG, adding 100 parts by weight of the treated PETG polyester, 0.3 part by weight of zinc acetate, 0.03 part by weight of an auxiliary catalyst sodium glycol and 100 parts by weight of glycol into a reaction kettle, introducing nitrogen, starting condensed water for refluxing, heating to 185 ℃, starting stirring, preserving heat and refluxing for 1h, and finishing the reaction to obtain a product after alcoholysis;
(2) polymerization reaction: adding 15 parts of polyethylene glycol and 15 parts of polypropylene glycol into the reaction kettle, adding 25 parts of isophthalic acid-5-sodium sulfonate, adding 0.3 part of polycondensation catalyst ethylene glycol titanium, 0.2 part of stabilizer trimethyl phosphate and 0.2 part of trimethyl phosphite, keeping the temperature, stirring for 30 minutes, heating to 255 ℃, vacuumizing to 100-200 Pa, and keeping the temperature for 2 hours; and heating to 270 ℃, vacuumizing at 20-40 Pa, preserving heat for 2h, and air-cooling and granulating to obtain the water-soluble polyester W4-PETG.
The obtained W4-PETG is stirred in hot water at 90 ℃ and can be completely dissolved in 25 minutes.
Although the specific embodiments of the present invention have been described with reference to the examples, the scope of the present invention is not limited thereto, and those skilled in the art will appreciate that various modifications and variations can be made without inventive effort by those skilled in the art based on the technical solution of the present invention.
Claims (10)
1. A method for preparing water-soluble polyester by waste PETG is characterized by comprising the following steps: the preparation method comprises the following preparation steps:
(1) performing PETG depolymerization, namely crushing the waste PETG polyester product by a crusher, washing and drying the crushed product to obtain pretreated PETG, adding 100 parts by weight of the treated PETG polyester, 0.1-0.5 part by weight of alcoholysis catalyst, 0.01-0.05 part by weight of auxiliary catalyst and 80 ~ 150 parts by weight of dihydric alcohol into a reaction kettle, introducing nitrogen, starting condensed water to reflux, heating to 185-197 ℃, starting stirring, preserving heat and refluxing for 0.5-4 h, and finishing reaction to obtain a product after alcoholysis;
(2) polymerization reaction: adding 5-30 parts of polyether, 10-30 parts of isophthalic acid-5-sulfonate or isophthalic acid-5-sulfonate derivative, 0.1-0.6 part of polycondensation catalyst and 0.1-0.8 part of stabilizer into the reaction kettle, keeping the temperature, stirring for 20-40 minutes, heating to 250-260 ℃, vacuumizing to 100-200 Pa, and keeping the temperature for 1-2 hours; and continuously heating to 265-270 ℃, vacuumizing to 20-40 Pa, preserving heat for 1-2 h, and air-cooling and granulating to obtain the water-soluble polyester W-PETG.
2. The method for preparing water-soluble polyester from waste PETG according to claim 1, wherein the method comprises the following steps: the waste polyester product in the step (1) is one or more than two of PETG bottle sheets, films and sheets.
3. The method for preparing water-soluble polyester from waste PETG according to claim 1, wherein the method comprises the following steps: the alcoholysis catalyst in the step (1) is one of zinc acetate, basic zinc acetate and sodium carbonate.
4. The method for preparing water-soluble polyester from waste PETG according to claim 1, wherein the method comprises the following steps: the auxiliary catalyst in the step (1) is sodium ethylene glycol.
5. The method for preparing water-soluble polyester from waste PETG according to claim 1, wherein the method comprises the following steps: in the step (1), the dihydric alcohol is one or two of ethylene glycol and propylene glycol.
6. The method for preparing water-soluble polyester from waste PETG according to claim 1, wherein the method comprises the following steps: in the step (1), the alcoholysis catalyst and the auxiliary catalyst are prepared into 10-18% by mass of ethylene glycol or propylene glycol solution and added into the reaction kettle.
7. The method for preparing water-soluble polyester from waste PETG according to claim 1, wherein the method comprises the following steps: and in the step (2), the polyether is one or two of polyethylene glycol and polypropylene glycol.
8. The method for preparing water-soluble polyester from waste PETG according to claim 1, wherein the method comprises the following steps: the isophthalic acid-5-sulfonate in the step (2) is isophthalic acid-5-sodium sulfonate, and the isophthalic acid-5-sulfonate derivative is one of dimethyl isophthalate-5-sodium sulfonate and dihydroxy ethyl isophthalate-5-sodium sulfonate.
9. The method for preparing water-soluble polyester from waste PETG according to claim 1, wherein the method comprises the following steps: and (3) the stabilizer in the step (2) is one or more than two of dimethyl phosphate, trimethyl phosphate, dimethyl phosphite and trimethyl phosphite.
10. The method for preparing water-soluble polyester from waste PETG according to claim 1, wherein the method comprises the following steps: and (3) preparing 10-18% by mass of ethylene glycol or propylene glycol solution from the isophthalic acid-5-sulfonate or the isophthalic acid-5-sulfonate derivative, a polycondensation catalyst and a stabilizer in the step (2) and adding the ethylene glycol or the propylene glycol solution into a reaction kettle.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201910864623.6A CN110606943A (en) | 2019-09-09 | 2019-09-09 | Method for preparing water-soluble polyester from waste PETG |
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| CN201910864623.6A CN110606943A (en) | 2019-09-09 | 2019-09-09 | Method for preparing water-soluble polyester from waste PETG |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112252061A (en) * | 2020-10-29 | 2021-01-22 | 湖南金全立生物科技股份有限公司 | Environment-friendly multifunctional dye-proofing agent and preparation method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0026006A1 (en) * | 1979-07-30 | 1981-04-01 | Tetra Laval Holdings & Finance SA | Laminated material and method of manufacturing it |
| CN102617839A (en) * | 2012-04-11 | 2012-08-01 | 山东巨业精细化工有限公司 | Method for preparing water-soluble polyesters for composite fibers by waste polyesters |
| CN106117528A (en) * | 2016-06-24 | 2016-11-16 | 江苏景宏新材料科技有限公司 | A kind of preparation method of high-performance regenerative PET G copolyesters |
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2019
- 2019-09-09 CN CN201910864623.6A patent/CN110606943A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0026006A1 (en) * | 1979-07-30 | 1981-04-01 | Tetra Laval Holdings & Finance SA | Laminated material and method of manufacturing it |
| CN102617839A (en) * | 2012-04-11 | 2012-08-01 | 山东巨业精细化工有限公司 | Method for preparing water-soluble polyesters for composite fibers by waste polyesters |
| CN106117528A (en) * | 2016-06-24 | 2016-11-16 | 江苏景宏新材料科技有限公司 | A kind of preparation method of high-performance regenerative PET G copolyesters |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112252061A (en) * | 2020-10-29 | 2021-01-22 | 湖南金全立生物科技股份有限公司 | Environment-friendly multifunctional dye-proofing agent and preparation method thereof |
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