CN114805779A - Method for synthesizing aromatic-aliphatic copolyester from aromatic polyester and product thereof - Google Patents
Method for synthesizing aromatic-aliphatic copolyester from aromatic polyester and product thereof Download PDFInfo
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- CN114805779A CN114805779A CN202210479385.9A CN202210479385A CN114805779A CN 114805779 A CN114805779 A CN 114805779A CN 202210479385 A CN202210479385 A CN 202210479385A CN 114805779 A CN114805779 A CN 114805779A
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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
- C08G63/91—Polymers modified by chemical after-treatment
- C08G63/914—Polymers modified by chemical after-treatment derived from polycarboxylic acids and polyhydroxy compounds
- C08G63/916—Dicarboxylic acids and dihydroxy compounds
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Abstract
The invention discloses a method for synthesizing aromatic-aliphatic copolyester by aromatic polyester and a product thereof. The method takes aliphatic dicarboxylic acid and commercial aromatic polyester as raw materials, and performs carboxyl-ester exchange reaction of aromatic polyester and aliphatic dicarboxylic acid under the conditions of decompression and heating, and removes the aromatic dicarboxylic acid to obtain the aromatic-aliphatic copolyester. The invention can utilize a large amount of recovered aromatic polyester materials to synthesize the aromatic-aliphatic copolyester with high added value by a one-pot method. The obtained product can be applied to the fields of fabrics, agricultural mulching films, food packaging, medical instruments and the like in a large scale, and the degradable performance of the product can further reduce the current environmental protection pressure.
Description
Technical Field
The invention relates to the technical field of high polymer material synthesis, in particular to a method for synthesizing aromatic-aliphatic copolyester by aromatic polyester and a product thereof.
Background
Due to environmental protection and sustainable development, relevant laws and regulations are set in many countries and regions around the world, and the use of non-degradable materials is limited.
Most of aromatic polyesters do not have degradability, while the aromatic-aliphatic copolyester takes good mechanical property of the aromatic polyesters and degradability of the aliphatic polyesters into account, and the physical and chemical properties of the aromatic polyesters can be regulated and controlled by regulating the composition of comonomers, so that the mechanical and processing forming properties of the aromatic polyesters are improved, and the aromatic-aliphatic copolyester is a biodegradable resin which is widely used.
Patent specification CN 110869413 a discloses a process for preparing biodegradable polyesters, in a first reaction step an aromatic acid is esterified with a diol and in a second reaction step an aliphatic acid is added to the reaction mixture. The technical idea of the patent is to prepare the polymer from the monomer, and the first reaction step can only obtain oligomer, and the molecular weight and the degree of polymerization are far inferior to those of commercial aromatic polyester high polymer. And the molar ratio of the diol to the aromatic acid in the first reaction step of the patent technology is 1.1-3.0, and the addition of the aliphatic acid in the second reaction step is still the esterification reaction process of the acid alcohol.
At present, the main approach for preparing degradable copolyester by using commercial aromatic polyester high polymer is to degrade the degradable copolyester into monomers and then to perform copolycondensation with aliphatic dicarboxylic acid. The price of the monomers obtained by degradation of aromatic polyesters is much higher than that of the original monomers, and the copolyesters obtained by this route are at a disadvantage in terms of cost.
Therefore, the invention directly reacts the aromatic polyester with the aliphatic dicarboxylic acid to obtain the aromatic-aliphatic copolyester with high molecular weight in one step.
Disclosure of Invention
The invention provides a method for synthesizing aromatic-aliphatic copolyester from aromatic polyester, which can synthesize the aromatic-aliphatic copolyester with high added value by a one-pot method by utilizing a large amount of recovered aromatic polyester materials. The obtained product can be applied to the fields of fabrics, agricultural mulching films, food packaging, medical instruments and the like in a large scale, and the degradable performance of the product can further reduce the current environmental protection pressure.
The specific technical scheme is as follows:
a method for synthesizing aromatic-aliphatic copolyester from aromatic polyester comprises the steps of taking aliphatic dicarboxylic acid and commercial aromatic polyester as raw materials, carrying out carboxyl-ester exchange reaction on the aromatic polyester and the aliphatic dicarboxylic acid under the conditions of decompression and heating, and removing the aromatic dicarboxylic acid to obtain the aromatic-aliphatic copolyester.
The principle of the invention is to utilize the characteristics of low sublimation heat and easy sublimation of the aromatic dicarboxylic acid, and extract the aromatic dicarboxylic acid generated by the reaction through the carboxyl-ester exchange reaction of the polymer and the monomer, thereby realizing the preparation of the high molecular weight aromatic-aliphatic copolyester.
In the method for synthesizing the aromatic-aliphatic copolyester from the aromatic polyester, the carboxyl-ester exchange reaction can be a melt reaction or a solid phase reaction.
In the method for synthesizing the aromatic-aliphatic copolyester from the aromatic polyester, the aliphatic dicarboxylic acid may include at least one of malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, octadecanedioic acid, nonadecane diacid, eicosanedioic acid, docosenoic acid, dimerized tetradecenoic acid, dimerized hexadecenoic acid, dimerized octadecenoic acid, hydrodimerized docosenoic acid, hydrodimerized tetradecenoic acid, hydrodimerized hexadecenoic acid, hydrodimerized octadecenoic acid, hydrodimerized eicosenoic acid, and hydrodimerized docosenoic acid.
In the method for synthesizing the aromatic-aliphatic copolyester from the aromatic polyester, the aromatic polyester can comprise at least one of polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, polyethylene isophthalate, polypropylene isophthalate, polybutylene isophthalate, polypentylene isophthalate, polyhexamethylene isophthalate, polypropylene terephthalate, polybutylene terephthalate, polypentylene terephthalate, polyhexamethylene isophthalate, polypropylene terephthalate, polybutylene terephthalate, polyhexamethylene phthalate, and polyethylene terephthalate.
Since some catalyst usually remains in the commercial aromatic polyester used as the raw material in the present invention, the method for synthesizing the aromatic-aliphatic copolyester from the aromatic polyester according to the present invention may be carried out by directly using the catalyst remaining in the commercial aromatic polyester as the raw material without adding an additional catalyst, or may be carried out by adding an additional catalyst to further promote the reaction.
In the method for synthesizing the aromatic-aliphatic copolyester from the aromatic polyester, the carboxyl-ester exchange reaction can be carried out under the action of a catalyst.
The catalyst may comprise at least one of a compound containing one or more metals of Ti, Ge, Zn, Fe, Mn, Co, Zr, Mg, Sb, Sn, V, Ir, La, Ce, Li, Ga, wherein: the Ti-containing compound may include at least one of tetra-n-butyl titanate, tetraethyl titanate, tetra-n-propyl titanate, tetra-isopropyl titanate, and tetra-isooctyl titanate; the Sn-containing compound may include at least one of dibutyltin oxide, stannous octoate, dibutyltin dilaurate, and stannous chloride; the Sb-containing compound may include at least one of antimony acetate or antimony trioxide.
In a preferred embodiment, in the method for synthesizing aromatic-aliphatic copolyester from aromatic polyester, the catalyst is used in an amount of 0-5% by weight, based on 100% by weight of the total of the aliphatic dicarboxylic acid, the aromatic polyester and the catalyst.
In a preferred embodiment, in the method for synthesizing the aromatic-aliphatic copolyester from the aromatic polyester, the total molar amount of the aromatic dicarboxylic acid units in the aromatic polyester is excessive relative to the molar amount of the aliphatic dicarboxylic acid in the raw materials.
More preferably, the aromatic polyester has a molar ratio of aromatic dicarboxylic acid units to aliphatic dicarboxylic acids in the raw material of 1:0.001 to 0.999.
In a preferred embodiment, in the method for synthesizing aromatic-aliphatic copolyester from aromatic polyester, the reaction temperature of the carboxyl-ester exchange reaction is 150 to 300 ℃, the reaction pressure is less than 100Pa, and the reaction time is 2 to 24 hours.
The invention also discloses the aromatic-aliphatic copolyester synthesized by the method, wherein the number average molecular weight of the aromatic-aliphatic copolyester can reach more than 25 kDa.
Compared with the prior art, the invention has the main advantages that:
1) the invention can convert the high molecular weight aromatic polyester into the high molecular weight aromatic-aliphatic copolyester in one step without the step of degrading into a monomer, thereby obviously reducing the cost.
2) The aromatic polyester used in the invention can be a recycled waste product, and provides a new way for recycling the aromatic polyester.
3) The aromatic-aliphatic copolyester synthesized by the invention has degradable performance and wider application range.
Drawings
FIG. 1 is a drawing of the poly (ethylene terephthalate-co-hydrodode-octadecenoic acid ethylene ester) product prepared in example 1 1 H NMR chart.
Detailed Description
The invention is further described with reference to the following drawings and specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The following examples are conducted under conditions not specified, usually according to conventional conditions, or according to conditions recommended by the manufacturer.
Example 1
17.98g of polyethylene terephthalate and 21.39g of hydrogenated dimeric octadecenoic acid are added into a 250mL three-neck flask, the feeding molar ratio of the terephthalic acid to the hydrogenated dimeric octadecenoic acid to the ethylene glycol is 1:0.4:1, the mixture is vacuumized and decompressed to be below 100Pa, the reaction temperature is 280 ℃, and the reaction time is 8 hours. After the reaction was complete, the product was tested to have a number average molecular weight of 48,200Da and a weight average molecular weight of 127,700 Da.
1 H NMR determined that the poly (ethylene terephthalate-co-hydrododecenoic acid ethylene glycol) product prepared in this example had a molar ratio of terephthalic acid, hydrododecenoic acid, and ethylene glycol units of 0.66:0.34: 1.
The poly (ethylene terephthalate-co-hydrodimeric deca-produced in this example is given in FIG. 1Ethylene glycol octaenoate) products 1 H NMR chart, it is shown that the composition molar ratio of dicarboxylic acid to diol in the final product is 1:1, thus satisfying the condition for obtaining high molecular weight copolyester.
Examples 2 to 4
The synthesis process is the same as that of example 1, except that the feeding molar ratios of the reduced terephthalic acid, the hydrogenated dimeric octadecenoic acid and the ethylene glycol are sequentially replaced by 1:0.3:1, 1:0.2:1 and 1:0.1:1, which correspond to example 2, example 3 and example 4 respectively.
The copolyester product obtained in example 2 was tested to have a number average molecular weight of 41,200Da and a weight average molecular weight of 102,400 Da.
The copolyester product obtained in example 3 had a number average molecular weight of 34,700Da and a weight average molecular weight of 79,800 Da.
The copolyester product obtained in example 4 had a number average molecular weight of 26,100Da and a weight average molecular weight of 57,400 Da.
Example 5
The synthesis process was the same as example 1, except that the reaction temperature was changed to 250 ℃ (solid phase reaction).
The copolyester product obtained in example 5 was tested to have a number average molecular weight of 39,300Da and a weight average molecular weight of 98,300 Da.
Example 6
The synthesis procedure was the same as in example 1, except that the reaction temperature was replaced with 290 ℃.
The copolyester product obtained in example 6 was tested to have a number average molecular weight of 49,800Da and a weight average molecular weight of 134,500 Da.
Example 7
The synthesis procedure is the same as in example 1, except that the reaction time is replaced by 5 hours.
The copolyester product obtained in example 7 was tested to have a number average molecular weight of 44,300Da and a weight average molecular weight of 114,700 Da.
Example 8
The synthesis procedure differs from example 1 only by replacing the reaction time by 24 hours.
The copolyester product obtained in example 8 was tested to have a number average molecular weight of 50,800Da and a weight average molecular weight of 132,100 Da.
Examples 9 to 12
The synthesis process is the same as that of example 1, except that hydrogenated dioctadecenoic acid is replaced by sebacic acid, dodecanedioic acid, hexadecanedioic acid and hydrogenated dihexadecenoic acid, respectively, which correspond to example 9, example 10, example 11 and example 12.
The copolyester product obtained in example 9 was tested to have a number average molecular weight of 42,500Da and a weight average molecular weight of 102,100 Da.
The copolyester product obtained in example 10 had a number average molecular weight of 43,200Da and a weight average molecular weight of 106,800 Da.
The copolyester product obtained in example 11 had a number average molecular weight of 44,400Da and a weight average molecular weight of 113,000 Da.
The copolyester product obtained in example 12 had a number average molecular weight of 45,800Da and a weight average molecular weight of 116,500 Da.
Examples 13 to 14
The synthesis process was the same as in example 1 except that polyethylene terephthalate was replaced with polyethylene isophthalate and polyethylene phthalate, respectively, and the process corresponded to example 13 and example 14, respectively.
The copolyester product obtained in example 13 was tested to have a number average molecular weight of 51,200Da and a weight average molecular weight of 138,400 Da.
The copolyester product obtained in example 14 had a number average molecular weight of 54,500Da and a weight average molecular weight of 148,900 Da.
Examples 15 to 16
The synthesis process is the same as that of example 1, except that the polyethylene terephthalate is replaced by polybutylene terephthalate and polyhexamethylene terephthalate, respectively, and the process corresponds to example 15 and example 16, respectively.
The copolyester product obtained in example 15 was tested to have a number average molecular weight of 50,100Da and a weight average molecular weight of 135,200 Da.
The copolyester product obtained in example 16 had a number average molecular weight of 47,200Da and a weight average molecular weight of 131,100 Da.
Example 17
The synthesis process was the same as in example 1, except that 500ppm of additional transesterification catalyst Sb was added 2 O 3
The copolyester product obtained in example 17 was tested to have a number average molecular weight of 48,800Da and a weight average molecular weight of 128,200 Da.
Furthermore, it should be understood that various changes and modifications can be made by one skilled in the art after reading the above description of the present invention, and equivalents also fall within the scope of the invention as defined by the appended claims.
Claims (8)
1. A method for synthesizing aromatic-aliphatic copolyester by aromatic polyester is characterized in that aliphatic dicarboxylic acid and commercial aromatic polyester are used as raw materials, under the conditions of pressure reduction and heating, carboxyl-ester exchange reaction of the aromatic polyester and the aliphatic dicarboxylic acid is carried out, and the aromatic dicarboxylic acid is removed to obtain the aromatic-aliphatic copolyester.
2. The method of claim 1, wherein the aliphatic dicarboxylic acid comprises at least one of malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, octadecanedioic acid, nonadecanedioic acid, eicosanedioic acid, docosaenoic acid, docosadienoic acid, hydrododecenoic acid, and hydrododecenoic acid.
3. The method of claim 1, wherein the aromatic polyester comprises at least one of polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, polybutylene terephthalate, polyethylene isophthalate, polypropylene isophthalate, polybutylene isophthalate, polyhexamethylene isophthalate, polypropylene terephthalate, polybutylene terephthalate, polyhexamethylene phthalate, and polyethylene terephthalate.
4. The process according to claim 1, wherein the carboxy-transesterification reaction is carried out under the action of a catalyst;
the catalyst comprises at least one of compounds containing one or more metals of Ti, Ge, Zn, Fe, Mn, Co, Zr, Mg, Sb, Sn, V, Ir, La, Ce, Li and Ga.
5. The method according to claim 4, wherein the catalyst is used in an amount of 0 to 5% by mass based on 100% by mass of the total of the aliphatic dicarboxylic acid, the aromatic polyester and the catalyst.
6. The method according to claim 1, wherein the molar ratio of the aromatic dicarboxylic acid unit in the aromatic polyester to the aliphatic dicarboxylic acid in the raw material is 1:0.001 to 0.999.
7. The method according to claim 1, wherein the reaction temperature of the carboxy-transesterification reaction is 150 to 300 ℃, the reaction pressure is 100Pa or less, and the reaction time is 2 to 24 hours.
8. An aromatic-aliphatic copolyester synthesized according to the method of any one of claims 1 to 7.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115558092A (en) * | 2022-10-09 | 2023-01-03 | 化学与精细化工广东省实验室 | Recycling method of waste PET and biodegradable copolyester prepared by adopting recycling method |
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| WO2020226200A1 (en) * | 2019-05-07 | 2020-11-12 | Tlc Korea Co., Ltd. | Biodegradable copolyester resin produced by esterification and polycondensation of biomass-derived aliphatic dicarboxylic acid and aromatic dicarboxylic acid with diol and production method thereof |
| CN111978528A (en) * | 2020-09-02 | 2020-11-24 | 浙江大学 | Method for synthesizing aromatic polyester without catalyst and product thereof |
| CN115124699A (en) * | 2021-03-26 | 2022-09-30 | 华润化学材料科技股份有限公司 | Degradable aromatic-aliphatic copolyester material and preparation method and application thereof |
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- 2022-05-05 CN CN202210479385.9A patent/CN114805779B/en active Active
Patent Citations (8)
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| US4476189A (en) * | 1983-05-16 | 1984-10-09 | American Hoechst Corporation | Copolyester primed polyester film |
| CN102477149A (en) * | 2010-11-29 | 2012-05-30 | 上海杰事杰新材料(集团)股份有限公司 | Preparation method of biodegradable aliphatic-aromatic copolyester |
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| CN111978528A (en) * | 2020-09-02 | 2020-11-24 | 浙江大学 | Method for synthesizing aromatic polyester without catalyst and product thereof |
| CN115124699A (en) * | 2021-03-26 | 2022-09-30 | 华润化学材料科技股份有限公司 | Degradable aromatic-aliphatic copolyester material and preparation method and application thereof |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115558092A (en) * | 2022-10-09 | 2023-01-03 | 化学与精细化工广东省实验室 | Recycling method of waste PET and biodegradable copolyester prepared by adopting recycling method |
| WO2024077921A1 (en) * | 2022-10-09 | 2024-04-18 | 化学与精细化工广东省实验室 | Recycling method for waste pet and biodegradable copolyester prepared by using same |
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