Preparation method of tertiary amine modified polyester capable of being rapidly degraded

Abstract

The present invention belongs to the technical field of copolymerization and modification of degradable polyesters and discloses a method for preparing a tertiary amine-modified rapidly degradable polyester. In this method, a tertiary amine, a dibasic acid, and a diol are subjected to esterification, pre-polycondensation, and polycondensation in the presence of a catalyst and an auxiliary agent to produce the tertiary amine-modified rapidly degradable polyester. The tertiary amine has a structural formula of RN(CH2CH2OH)2, where R is a pendant group containing at least one hydroxyl group. The preparation method of the present invention is simple and easy to implement. The prepared tertiary amine-modified rapidly degradable polyester can be hydrolyzed, with a mass loss of 3% to 20% within 49 days. Hydrolysis is further accelerated, particularly after oxidation treatment, while also enhancing the breaking strength of the copolyester.

Description

Technical Field

[0001] The invention belongs to the technical field of copolymerization modification of degradable polyesters and relates to a preparation method of tertiary amine-modified rapidly degradable polyester. Background Art

[0002] The development of biodegradable polyester products is of great significance to alleviating plastic pollution. However, current biodegradable polyester products, such as PBAT, PBS, PBST, etc., degrade extremely slowly in the natural environment and require controlled composting conditions to achieve degradation. However, controlled composting seriously occupies land resources and is not in line with future development laws.

[0003] In order to improve the degradation performance of the above-mentioned degradable polyester products, there are several modification methods:

[0004] 1) Introducing easily degradable segments: For example, patents with authorization publication numbers CN113736073B and CN114573965B and patent application publication number CN118562108A all introduce ether-containing monomers (such as diglycolic acid) into the polyester molecular chain. By constructing a high-density ether bond, the hydrophilicity of the copolyester is greatly enhanced, allowing the copolyester to be rapidly hydrolyzed. Patent application publication number CN119591852A discloses a PBAT-PLA copolyester and a preparation method thereof. This method introduces PLA segments into PBAT and utilizes the easily degradable nature of the PLA segments to improve the degradation performance of the copolyester.

[0005] 2) Blending of easily degradable components: For example, patent applications with publication numbers CN119661999A, CN119432034A, CN119350825A, and CN119639199A all blend and modify PBAT with PLA to prepare a variety of products, thereby improving the application performance of the original polyester.

[0006] 3) Introducing molecular switches for controlled degradation: For example, patent application CN114507329A discloses a pH-responsive, controllably degradable polyurethane and its preparation method. This method enables the product to achieve rapid bond scission in an acidic environment. However, the heat resistance of the silyl ether bond is poor and it is easily decomposed above 180°C. This does not meet the polymerization process requirements of common polyesters and can only be chain extended using isocyanates.

[0007] In summary, although there are many methods for degradation modification of degradable polyesters in the existing technology, all of them have certain effects. However, there are also some major problems as follows:

[0008] (1) Regarding the introduction of easily degradable segments: This method can enhance the hydrophilicity of the copolyester, accelerate the degradation performance, and achieve rapid hydrolysis by introducing diglycolic acid and lactic acid components. However, diglycolic acid and lactic acid are flexible segments, and their introduction will inevitably destroy the regular molecular chain structure of the copolyester and reduce the breaking strength of the copolyester. It is not advisable to enhance the degradation performance at the expense of strength.

[0009] (2) For blending easily degradable components: Although the blending modification process of this method is simple and low-cost, and toughening and strengthening can also be achieved, the compatibility between the multiple components is the first problem to be solved. In addition, although the easily degradable components can be rapidly degraded in the early stage of degradation, they do not change the original copolyester molecular chain structure, and have limited effect on improving the degradation performance of the copolyester;

[0010] (3) Regarding the introduction of molecular switches and controlled degradation: Although this method can achieve controlled degradation of polyester, it can well maintain the mechanical properties of copolyester during use and can also achieve rapid degradation through special treatment after disposal. However, the special treatment conditions of molecular switches are sometimes more harsh. For example, strong acid or strong alkaline environments are highly corrosive to equipment. In addition, molecular switches often introduce special compounds due to their special functions. Their cost is high or the preparation process is complicated, which is not conducive to large-scale preparation. The safety of the degradation products also needs further verification.

[0011] Therefore, it is of great significance to study a preparation method of tertiary amine-modified rapidly degradable polyester to solve the above problems. Summary of the Invention

[0012] The purpose of the present invention is to solve the problems existing in the prior art and provide a method for preparing tertiary amine modified rapidly degradable polyester.

[0013] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0014] A method for preparing a tertiary amine-modified rapidly degradable polyester comprises: in the presence of a catalyst and an auxiliary agent, subjecting a tertiary amine, a dibasic acid and a diol to esterification, pre-polycondensation and polycondensation to prepare the tertiary amine-modified rapidly degradable polyester;

[0015] The tertiary amine is a polyhydroxy tertiary amine compound with the structural formula RN(CH2CH2OH)2, wherein R is a side group, and the side group contains at least one hydroxyl group;

[0016] The addition amount of tertiary amine is 0.3~1.2% of the molar content of dibasic acid. When the addition amount is too low, the catalytic effect of tertiary amine is insufficient. When the addition amount is too high, a cross-linked network is easily formed, which will limit the processing and application of the material in the rheological field dominated by tension.

[0017] In a 60°C water environment, the tertiary amine-modified rapidly degradable polyester can be hydrolyzed, with a mass loss of 3.2-20% in 49 days;

[0018] The number average molecular weight of the rapidly degradable polyester modified with tertiary amine decreased by 3-40% after oxidation treatment. The oxidation treatment was performed by immersing the polyester in a 30 wt% hydrogen peroxide solution at 30°C for 8 h.

[0019] The tertiary amine-modified rapidly degradable polyester was oxidized and then treated in a 60°C water environment, and the mass loss in 49 days was 11.3~40%.

[0020] In the present invention, the dibasic acid may also be replaced by an ester of the dibasic acid, and similar effects may also be achieved.

[0021] The present invention uses polyhydroxy tertiary amines to copolymerize and modify polyester. To ensure the reaction, the number of hydroxyl functional groups must be greater than or equal to 2. However, polyhydroxy tertiary amines with 2 functional groups, such as N-methyldiethanolamine and N-ethyldiethanolamine, are extremely susceptible to oxidative degradation at high temperatures (150°C) and do not meet the polyester polymerization process flow. After screening, it was found that polyhydroxy tertiary amines (hydroxyl groups ≥ 3) have good thermal stability and can be used for polyester copolymerization modification.

[0022] On the one hand, tertiary amines contain lone pairs of electrons, which can enhance the hydrophilicity of copolyesters. In addition, tertiary amines are weakly alkaline in aqueous solution. For example, the pH value of a 1 mol% triethanolamine aqueous solution at 25°C is 10.5~11.5. The construction of a weakly alkaline environment in the copolyester molecular chain can catalyze the breaking of ester bonds near the tertiary amine and accelerate degradation. On the other hand, although branching will limit the degradation rate of copolyesters, when tertiary amines are close to unstable groups (such as ester bonds, the hydroxyl groups in tertiary amines form ester bonds after esterification reaction), a cope elimination reaction can occur at a significantly lower temperature. After the tertiary amine is oxidized, β-H can directly undergo an elimination reaction to generate hydroxylamine and olefins, destroying the branched structure and accelerating degradation.

[0023] In addition, the tertiary amine used in the present invention contains multiple hydroxyl functional groups. The polyhydroxy structure can form a branched network during the polymerization process, increase molecular chain entanglement, thereby enhancing melt viscosity and improving processability; branched entanglement can also slightly enhance the breaking strength of the copolyester.

[0024] As the preferred technical solution:

[0025] In the above-mentioned method for preparing a tertiary amine-modified rapidly degradable polyester, the tertiary amine is triethanolamine or bis(2-hydroxyethyl)amino(trihydroxymethyl)methane, preferably triethanolamine.

[0026] The method for preparing a tertiary amine-modified rapidly degradable polyester as described above comprises the following steps: the dibasic acid is dibasic acid I, or a mixed acid of dibasic acid I and dibasic acid II; the dibasic acid I is one or more of 1,4-butanediol, 1,5-pentanedioic acid, 1,6-hexanediol, 1,7-heptanedioic acid, 1,8-octanedioic acid, 1,9-nonanediol, and 1,10-decanedioic acid; the dibasic acid II is terephthalic acid; the molar percentage of dibasic acid I in the dibasic acid is 50-60% or 100%; and the diol is ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, or 1,6-hexanediol.

[0027] In the above-mentioned method for preparing a tertiary amine-modified rapidly degradable polyester, the molar ratio of the dibasic acid to the diol is 1:1.1-1.3.

[0028] In the above-mentioned method for preparing a tertiary amine-modified rapidly degradable polyester, the catalyst is tetrabutyl titanate or antimony ethylene glycol, and the amount of catalyst added is 300-1000 ppm based on the mass of the dibasic acid.

[0029] The preparation method of the tertiary amine-modified rapidly degradable polyester as described above, wherein the auxiliary agents are a heat stabilizer and an ether-proof agent, the heat stabilizer is triphenyl phosphate or triphenyl phosphite, the ether-proof agent is anhydrous sodium acetate, and the addition amounts of the heat stabilizer and the ether-proof agent are both 300-1000 ppm of the mass of the dibasic acid.

[0030] The method for preparing a tertiary amine-modified rapidly degradable polyester as described above comprises an esterification temperature of 160-220° C., an esterification pressure of 0.1-0.6 MPa, and an esterification termination condition when the water output exceeds 95% of the theoretical value.

[0031] The pre-condensation temperature is 180~240℃, the pre-condensation time is 0.5~1.5h, and the pre-condensation pressure is 1~10kPa;

[0032] The polycondensation temperature is 200~260℃, the polycondensation pressure is ≤80Pa, and the polycondensation time is 1~3h. The introduction of tertiary amine can quickly shorten the polycondensation time.

[0033] A method for preparing a tertiary amine-modified rapidly degradable polyester as described in any of the above items, wherein the tertiary amine-modified rapidly degradable polyester has an intrinsic viscosity of 1.06-1.20 dL / g, a number average molecular weight greater than 30,000 g / mol, a color b value of 3-10, and a water static contact angle of 72°-80.5°.

[0034] As described above, a method for preparing a tertiary amine-modified rapidly degradable polyester has a breaking strength of 14.0~34.2MPa, which is slightly improved compared to the polyester without tertiary amine modification.

[0035] Beneficial effects:

[0036] (1) The tertiary amine used in the present invention contains lone pairs of electrons, which can effectively improve the hydrophilicity of the reinforced copolyester. At the same time, the tertiary amine is weakly alkaline in aqueous solution and can also catalyze the cleavage of ester bonds near the tertiary amine, thereby accelerating degradation. In addition, after the tertiary amine is oxidized, β-H can directly undergo an elimination reaction to generate hydroxylamine and olefin, destroying the branched structure and accelerating degradation.

[0037] (2) The tertiary amine used in the present invention contains multiple hydroxyl functional groups. The polyhydroxy structure can form a branched network during the polymerization process, increase the entanglement of molecular chains, thereby enhancing the melt viscosity and improving the processability; the branched entanglement can also slightly enhance the breaking strength of the copolyester. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The mechanical property curves of the commercial PBAT of the present invention and the tertiary amine-modified rapidly degradable polyester prepared in Examples 1 and 2 are shown;

[0039] Figure 2 Schematic diagram of the hydrophilicity of the commercial PBAT of the present invention and the tertiary amine-modified rapidly degradable polyester prepared in Examples 1 and 2;

[0040] Figure 3 Schematic diagram of the degradation performance of commercial PBAT of the present invention and the tertiary amine-modified rapidly degradable polyester prepared in Examples 1 and 2 in a neutral water environment. DETAILED DESCRIPTION

[0041] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.

[0042] The testing methods for the relevant performance indicators in the following embodiments and comparative examples are as follows:

[0043] Intrinsic viscosity: The tertiary amine-modified rapidly degradable polyester prepared in each example was used as a sample, and the intrinsic viscosity of the sample was measured with reference to the standard GB / T 14190-2017 "Test Method for Fiber-Grade Polyester (PET) Chips".

[0044] Color b-value: The tertiary amine-modified rapidly degradable polyester prepared in each example was used as a sample, and the color b-value of the sample was measured with reference to the standard GB / T 17931-2018 "Polyethylene terephthalate (PET) resin for bottles".

[0045] Breaking strength: The tertiary amine-modified rapidly degradable polyester prepared in each example was used as a sample, and the breaking strength of the sample was measured according to ISO 527 “Test method for tensile properties of plastics”.

[0046] Mass loss: The tertiary amine-modified rapidly degradable polyester prepared in each example was used as a sample, and then the sample was prepared into a 10 mm × 10 mm × 0.3 mm film by hot pressing. The film was then immersed in 60°C PBS buffer (pH 7.2, bath ratio 1:125) and degraded for 49 days. The mass change of the sample before and after degradation was recorded and the mass loss was calculated.

[0047] Example 1

[0048] A method for preparing a tertiary amine-modified rapidly degradable polyester comprises the following steps:

[0049] (1) Preparation of raw materials;

[0050] Tertiary amine: triethanolamine;

[0051] Dibasic acid: a mixed acid of 1,6-adipic acid and terephthalic acid, wherein the molar percentage of 1,6-adipic acid in the dibasic acid is 50%;

[0052] Diol: 1,4-butanediol;

[0053] Catalyst: tetrabutyl titanate;

[0054] Heat stabilizer: triphenyl phosphite;

[0055] Ether-proof agent: anhydrous sodium acetate;

[0056] (2) After uniformly mixing the tertiary amine, dibasic acid, diol, catalyst, heat stabilizer and anti-ether agent, an esterification reaction is carried out at a pressure of 0.2 MPa and a temperature of 200°C until the water output exceeds 95% of the theoretical value, and then the esterification reaction is terminated; wherein, the amount of tertiary amine added is 0.5% of the molar content of the dibasic acid, the molar ratio of the dibasic acid to the diol is 1:1.2, the amount of catalyst added is 500 ppm of the mass of the dibasic acid, the amount of heat stabilizer added is 500 ppm of the mass of the dibasic acid, and the amount of anti-ether agent added is 500 ppm of the mass of the dibasic acid;

[0057] (3) The product after the esterification reaction in step (2) was pre-condensed at a temperature of 240°C and a pressure of 5 kPa for 1 hour, and then polycondensed at a temperature of 260°C and a pressure of 50 Pa for 1.8 hours to obtain a tertiary amine-modified rapidly degradable polyester.

[0058] The resulting tertiary amine-modified rapidly degradable polyester had an intrinsic viscosity of 1.15 dL / g, a number-average molecular weight of 58,667 g / mol, a color b value of 7.6, a water static contact angle of 79.9°, and a breaking strength of 21 MPa.

[0059] In a 60°C water environment, the mass loss of the rapidly degradable polyester modified with tertiary amine was 7.6% in 49 days;

[0060] After tertiary amine-modified rapidly degradable polyester was immersed in 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the number average molecular weight decreased by 12.7%;

[0061] After being immersed in a 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the treated tertiary amine-modified rapidly degradable polyester was further treated in a 60 ° C water environment, and the mass loss in 49 days was 14.7%.

[0062] Example 2

[0063] A method for preparing a tertiary amine-modified rapidly degradable polyester is basically the same as Example 1, except that the amount of tertiary amine added in step (2) is 1% of the molar content of the dibasic acid, and the polycondensation time in step (3) is 1.4 h.

[0064] The resulting tertiary amine-modified rapidly degradable polyester had an intrinsic viscosity of 1.15 dL / g, a number-average molecular weight of 62,893 g / mol, a color b value of 8.2, a water static contact angle of 76.8°, and a breaking strength of 19.6 MPa.

[0065] In a 60°C water environment, the mass loss of the rapidly degradable polyester modified with tertiary amines was 3.9% in 49 days;

[0066] After the tertiary amine-modified rapidly degradable polyester was immersed in a 30 wt% hydrogen peroxide solution at 30°C for 8 h, the number average molecular weight decreased by 20.8%.

[0067] After being immersed in a 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the treated tertiary amine-modified rapidly degradable polyester was further treated in a 60 ° C water environment, and the mass loss in 49 days was 18.8%.

[0068] The mechanical properties, hydrophilicity and degradation properties of the tertiary amine modified rapidly degradable polyester prepared in Examples 1 and 2 were compared with those of commercial PBAT (produced by BASF, brand name ecoflex C1200). The results are as follows: Figures 1-3 As shown in the figure, it can be seen that compared with commercial PBAT, the tertiary amine modified rapidly degradable polyester prepared in Examples 1 to 2 can enhance the breaking strength and hydrolysis performance of the copolyester after the introduction of triethanolamine.

[0069] Example 3

[0070] A method for preparing a tertiary amine-modified rapidly degradable polyester comprises the following steps:

[0071] (1) Preparation of raw materials;

[0072] Tertiary amine: triethanolamine;

[0073] Dibasic acid: a mixed acid of 1,4-butanedioic acid and terephthalic acid, with 1,4-butanedioic acid accounting for 50% by mole of the dibasic acid;

[0074] Diol: 1,4-butanediol;

[0075] Catalyst: tetrabutyl titanate;

[0076] Heat stabilizer: triphenyl phosphate;

[0077] Ether-proof agent: anhydrous sodium acetate;

[0078] (2) After uniformly mixing the tertiary amine, dibasic acid, diol, catalyst, heat stabilizer and anti-ether agent, an esterification reaction is carried out under the conditions of a pressure of 0.3 MPa and a temperature of 220°C until the water output exceeds 95% of the theoretical value, and then the esterification reaction is terminated; wherein, the amount of tertiary amine added is 0.8% of the molar content of the dibasic acid, the molar ratio of the dibasic acid to the diol is 1:1.15, the amount of catalyst added is 600 ppm of the mass of the dibasic acid, the amount of heat stabilizer added is 800 ppm of the mass of the dibasic acid, and the amount of anti-ether agent added is 500 ppm of the mass of the dibasic acid;

[0079] (3) The product after the esterification reaction in step (2) was pre-condensed at a temperature of 230°C and a pressure of 1 kPa for 1.5 hours, and then polycondensed at a temperature of 255°C and a pressure of 80 Pa for 2 hours to obtain a tertiary amine-modified rapidly degradable polyester.

[0080] The resulting tertiary amine-modified rapidly degradable polyester had an intrinsic viscosity of 1.06 dL / g, a number-average molecular weight of 51,891 g / mol, a color b value of 8.9, a water static contact angle of 79.1°, and a breaking strength of 25.8 MPa.

[0081] In a 60°C water environment, the tertiary amine-modified rapidly degradable polyester has a mass loss of 3% in 49 days;

[0082] After tertiary amine-modified rapidly degradable polyester was immersed in 30 wt% hydrogen peroxide solution at 30°C for 8 h, the number average molecular weight decreased by 18.4%.

[0083] After being immersed in a 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the treated tertiary amine-modified rapidly degradable polyester was further treated in a 60 ° C water environment, and the mass loss in 49 days was 17.5%.

[0084] Example 4

[0085] A method for preparing a tertiary amine-modified rapidly degradable polyester comprises the following steps:

[0086] (1) Preparation of raw materials;

[0087] Tertiary amine: triethanolamine;

[0088] Dibasic acid: composed of 1,4-butanediol and 1,6-hexanediol in a molar ratio of 1:1;

[0089] Diol: 1,4-butanediol;

[0090] Catalyst: tetrabutyl titanate;

[0091] Heat stabilizer: triphenyl phosphate;

[0092] Ether-proof agent: anhydrous sodium acetate;

[0093] (2) After uniformly mixing the tertiary amine, dibasic acid, diol, catalyst, heat stabilizer and anti-ether agent, an esterification reaction is carried out under the conditions of a pressure of 0.3 MPa and a temperature of 180°C until the water output exceeds 95% of the theoretical value, and then the esterification reaction is terminated; wherein, the amount of tertiary amine added is 1% of the molar content of the dibasic acid, the molar ratio of the dibasic acid to the diol is 1:1.2, the amount of catalyst added is 800 ppm of the mass of the dibasic acid, the amount of heat stabilizer added is 400 ppm of the mass of the dibasic acid, and the amount of anti-ether agent added is 400 ppm of the mass of the dibasic acid;

[0094] (3) The product after the esterification reaction in step (2) was pre-polycondensed at a temperature of 200°C and a pressure of 3 kPa for 1.5 h, and then polycondensed at a temperature of 220°C and a pressure of 70 Pa for 1.6 h to obtain a tertiary amine-modified rapidly degradable polyester.

[0095] The resulting tertiary amine-modified rapidly degradable polyester had an intrinsic viscosity of 1.09 dL / g, a number-average molecular weight of 53,875 g / mol, a color b value of 5.9, a water static contact angle of 76.1°, and a breaking strength of 17.6 MPa.

[0096] In a 60°C water environment, the mass loss of the rapidly degradable polyester modified with tertiary amine was 12.8% in 49 days;

[0097] After the tertiary amine-modified rapidly degradable polyester was immersed in a 30 wt% hydrogen peroxide solution at 30°C for 8 h, the number average molecular weight decreased by 25.1%.

[0098] After being immersed in a 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the treated tertiary amine-modified rapidly degradable polyester was further treated in a 60 ° C water environment, and the mass loss in 49 days was 33.1%.

[0099] Example 5

[0100] A method for preparing a tertiary amine-modified rapidly degradable polyester comprises the following steps:

[0101] (1) Preparation of raw materials;

[0102] Tertiary amine: triethanolamine;

[0103] Dibasic acid: 1,4-butanedioic acid;

[0104] Diol: 1,4-butanediol;

[0105] Catalyst: tetrabutyl titanate;

[0106] Heat stabilizer: triphenyl phosphite;

[0107] Ether-proof agent: anhydrous sodium acetate;

[0108] (2) After uniformly mixing the tertiary amine, dibasic acid, diol, catalyst, heat stabilizer and anti-ether agent, an esterification reaction is carried out under the conditions of a pressure of 0.1 MPa and a temperature of 160°C until the water output exceeds 95% of the theoretical value and then the esterification reaction is terminated; wherein, the amount of tertiary amine added is 1.2% of the molar content of the dibasic acid, the molar ratio of the dibasic acid to the diol is 1:1.2, the amount of catalyst added is 1000 ppm by mass of the dibasic acid, the amount of heat stabilizer added is 300 ppm by mass of the dibasic acid, and the amount of anti-ether agent added is 300 ppm by mass of the dibasic acid;

[0109] (3) The product after the esterification reaction in step (2) was pre-condensed at a temperature of 180°C and a pressure of 6 kPa for 0.5 h, and then polycondensed at a temperature of 210°C and a pressure of 30 Pa for 1.3 h to obtain a tertiary amine-modified rapidly degradable polyester.

[0110] The resulting tertiary amine-modified rapidly degradable polyester had an intrinsic viscosity of 1.17 dL / g, a number-average molecular weight of 63,675 g / mol, a color b value of 3, a water static contact angle of 74.9°, and a breaking strength of 34.2 MPa.

[0111] In a 60°C water environment, the mass loss of the rapidly degradable polyester modified with tertiary amines was 5.7% in 49 days;

[0112] After tertiary amine-modified rapidly degradable polyester was immersed in 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the number average molecular weight decreased by 25.8%;

[0113] After being immersed in a 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the treated tertiary amine-modified rapidly degradable polyester was further treated in a 60 ° C water environment, and the mass loss in 49 days was 20.2%.

[0114] Example 6

[0115] A method for preparing a tertiary amine-modified rapidly degradable polyester comprises the following steps:

[0116] (1) Preparation of raw materials;

[0117] Tertiary amine: triethanolamine;

[0118] Dibasic acid: 1,10-decanedioic acid;

[0119] Diol: 1,6-hexanediol;

[0120] Catalyst: antimony glycol;

[0121] Heat stabilizer: triphenyl phosphate;

[0122] Ether-proof agent: anhydrous sodium acetate;

[0123] (2) After uniformly mixing the tertiary amine, dibasic acid, diol, catalyst, heat stabilizer and anti-ether agent, an esterification reaction is carried out at a pressure of 0.2 MPa and a temperature of 200°C until the water output exceeds 95% of the theoretical value, and then the esterification reaction is terminated; wherein, the amount of tertiary amine added is 1.2% of the molar content of the dibasic acid, the molar ratio of the dibasic acid to the diol is 1:1.25, the amount of catalyst added is 500 ppm of the mass of the dibasic acid, the amount of heat stabilizer added is 700 ppm of the mass of the dibasic acid, and the amount of anti-ether agent added is 700 ppm of the mass of the dibasic acid;

[0124] (3) The product after the esterification reaction in step (2) was pre-condensed at a temperature of 220°C and a pressure of 10 kPa for 1.5 h, and then polycondensed at a temperature of 230°C and a pressure of 60 Pa for 1.1 h to obtain a tertiary amine-modified rapidly degradable polyester.

[0125] The resulting tertiary amine-modified rapidly degradable polyester had an intrinsic viscosity of 1.15 dL / g, a number-average molecular weight of 57,345 g / mol, a color b value of 5.7, a water static contact angle of 72°, and a breaking strength of 14 MPa.

[0126] In a 60°C water environment, the tertiary amine-modified polyester can be rapidly degraded with a mass loss of 20% in 49 days;

[0127] After tertiary amine-modified rapidly degradable polyester was immersed in 30 wt% hydrogen peroxide solution at 30°C for 8 h, the number average molecular weight decreased by 36.8%.

[0128] After being immersed in a 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the treated tertiary amine-modified rapidly degradable polyester was treated in a 60 ° C water environment, and the mass loss was 40% in 49 days.

[0129] Example 7

[0130] A method for preparing a tertiary amine-modified rapidly degradable polyester comprises the following steps:

[0131] (1) Preparation of raw materials;

[0132] Tertiary amine: triethanolamine;

[0133] Dibasic acid: 1,5-glutaric acid;

[0134] Diol: ethylene glycol;

[0135] Catalyst: antimony glycol;

[0136] Heat stabilizer: triphenyl phosphite;

[0137] Ether-proof agent: anhydrous sodium acetate;

[0138] (2) After uniformly mixing the tertiary amine, dibasic acid, diol, catalyst, heat stabilizer and anti-ether agent, an esterification reaction is carried out under the conditions of a pressure of 0.6 MPa and a temperature of 180°C until the water output exceeds 95% of the theoretical value and then the esterification reaction is terminated; wherein, the amount of tertiary amine added is 0.5% of the molar content of the dibasic acid, the molar ratio of the dibasic acid to the diol is 1:1.1, the amount of catalyst added is 300 ppm of the mass of the dibasic acid, the amount of heat stabilizer added is 300 ppm of the mass of the dibasic acid, and the amount of anti-ether agent added is 300 ppm of the mass of the dibasic acid;

[0139] (3) The product after the esterification reaction in step (2) was pre-condensed at a temperature of 200°C and a pressure of 10 kPa for 1 hour, and then polycondensed at a temperature of 210°C and a pressure of 30 Pa for 2 hours to obtain a tertiary amine-modified rapidly degradable polyester.

[0140] The resulting tertiary amine-modified rapidly degradable polyester had an intrinsic viscosity of 1.08 dL / g, a number-average molecular weight of 50,676 g / mol, a color b value of 5.4, a water static contact angle of 78.7°, and a breaking strength of 16.7 MPa.

[0141] In a 60°C water environment, the mass loss of the rapidly degradable polyester modified with tertiary amine was 15.4% in 49 days;

[0142] After the tertiary amine-modified rapidly degradable polyester was immersed in a 30 wt% hydrogen peroxide solution at 30°C for 8 h, the number average molecular weight decreased by 20.1%.

[0143] After being immersed in a 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the treated tertiary amine-modified rapidly degradable polyester was further treated in a 60 ° C water environment, and the mass loss in 49 days was 27.8%.

[0144] Example 8

[0145] A method for preparing a tertiary amine-modified rapidly degradable polyester comprises the following steps:

[0146] (1) Preparation of raw materials;

[0147] Tertiary amine: triethanolamine;

[0148] Dibasic acid: 1,7-pimelic acid;

[0149] Diol: 1,3-propylene glycol;

[0150] Catalyst: tetrabutyl titanate;

[0151] Heat stabilizer: triphenyl phosphate;

[0152] Ether-proof agent: anhydrous sodium acetate;

[0153] (2) After uniformly mixing the tertiary amine, dibasic acid, diol, catalyst, heat stabilizer and anti-ether agent, an esterification reaction is carried out at a pressure of 0.6 MPa and a temperature of 200°C until the water output exceeds 95% of the theoretical value, and then the esterification reaction is terminated; wherein, the amount of tertiary amine added is 1% of the molar content of the dibasic acid, the molar ratio of the dibasic acid to the diol is 1:1.2, the amount of catalyst added is 800 ppm of the mass of the dibasic acid, the amount of heat stabilizer added is 500 ppm of the mass of the dibasic acid, and the amount of anti-ether agent added is 500 ppm of the mass of the dibasic acid;

[0154] (3) The product after the esterification reaction in step (2) was pre-polycondensed at a temperature of 220° C. and a pressure of 1 kPa for 1 hour, and then polycondensed at a temperature of 220° C. and a pressure of 60 Pa for 1.8 hours to obtain a tertiary amine-modified rapidly degradable polyester.

[0155] The resulting tertiary amine-modified rapidly degradable polyester had an intrinsic viscosity of 1.12 dL / g, a number-average molecular weight of 55,545 g / mol, a color b value of 8.1, a water static contact angle of 75.9°, and a breaking strength of 15.4 MPa.

[0156] In a 60°C water environment, the mass loss of the rapidly degradable polyester modified with tertiary amine was 16.8% in 49 days;

[0157] After tertiary amine-modified rapidly degradable polyester was immersed in 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the number average molecular weight decreased by 28.8%;

[0158] After being immersed in a 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the treated tertiary amine-modified rapidly degradable polyester was further treated in a 60 ° C water environment, and the mass loss in 49 days was 34.2%.

[0159] Example 9

[0160] A method for preparing a tertiary amine-modified rapidly degradable polyester comprises the following steps:

[0161] (1) Preparation of raw materials;

[0162] Tertiary amine: triethanolamine;

[0163] Dibasic acid: a mixed acid of 1,8-octanedioic acid and terephthalic acid, with 1,8-octanedioic acid accounting for 60% by mole of the dibasic acid;

[0164] Diol: ethylene glycol;

[0165] Catalyst: antimony glycol;

[0166] Heat stabilizer: triphenyl phosphite;

[0167] Ether-proof agent: anhydrous sodium acetate;

[0168] (2) After uniformly mixing the tertiary amine, dibasic acid, diol, catalyst, heat stabilizer and anti-ether agent, an esterification reaction is carried out under the conditions of a pressure of 0.6 MPa and a temperature of 220°C until the water output exceeds 95% of the theoretical value and then the esterification reaction is terminated; wherein, the amount of tertiary amine added is 1.2% of the molar content of the dibasic acid, the molar ratio of the dibasic acid to the diol is 1:1.1, the amount of catalyst added is 300 ppm of the mass of the dibasic acid, the amount of heat stabilizer added is 300 ppm of the mass of the dibasic acid, and the amount of anti-ether agent added is 300 ppm of the mass of the dibasic acid;

[0169] (3) The product after the esterification reaction in step (2) was pre-condensed at a temperature of 240°C and a pressure of 5 kPa for 1 hour, and then polycondensed at a temperature of 250°C and a pressure of 40 Pa for 1 hour to obtain a tertiary amine-modified rapidly degradable polyester.

[0170] The resulting tertiary amine-modified rapidly degradable polyester had an intrinsic viscosity of 1.2 dL / g, a number-average molecular weight of 66,785 g / mol, a color b value of 10, a water static contact angle of 74°, and a breaking strength of 17.8 MPa.

[0171] In a 60°C water environment, the mass loss of the rapidly degradable polyester modified with tertiary amine was 10.7% in 49 days;

[0172] After tertiary amine-modified rapidly degradable polyester was immersed in a 30wt% hydrogen peroxide solution at 30°C for 8 hours, the number average molecular weight decreased by 40%.

[0173] After being immersed in a 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the treated tertiary amine-modified rapidly degradable polyester was further treated in a 60 ° C water environment, and the mass loss in 49 days was 38.6%.

[0174] Example 10

[0175] A method for preparing a tertiary amine-modified rapidly degradable polyester comprises the following steps:

[0176] (1) Preparation of raw materials;

[0177] Tertiary amine: bis(2-hydroxyethyl)amino(trihydroxymethyl)methane;

[0178] Dibasic acid: dimethyl adipate;

[0179] Diol: 1,5-pentanediol;

[0180] Catalyst: tetrabutyl titanate;

[0181] Heat stabilizer: triphenyl phosphate;

[0182] Ether-proof agent: anhydrous sodium acetate;

[0183] (2) After uniformly mixing the tertiary amine, dibasic acid, diol, catalyst, heat stabilizer and anti-ether agent, an esterification reaction is carried out under the conditions of a pressure of 0.6 MPa and a temperature of 220°C until the water output exceeds 95% of the theoretical value, and then the esterification reaction is terminated; wherein, the amount of tertiary amine added is 0.3% of the molar content of the dibasic acid, the molar ratio of the dibasic acid to the diol is 1:1.3, the amount of catalyst added is 800 ppm by mass of the dibasic acid, the amount of heat stabilizer added is 1000 ppm by mass of the dibasic acid, and the amount of anti-ether agent added is 1000 ppm by mass of the dibasic acid;

[0184] (3) The product after the esterification reaction in step (2) was pre-condensed at a temperature of 210° C. and a pressure of 3 kPa for 1 hour, and then polycondensed at a polycondensation temperature of 220° C. and a polycondensation pressure of 40 Pa for 2.5 hours to obtain a tertiary amine-modified rapidly degradable polyester.

[0185] The resulting tertiary amine-modified rapidly degradable polyester had an intrinsic viscosity of 1.08 dL / g, a number-average molecular weight of 42,757 g / mol, a color b value of 7.4, a water static contact angle of 80.5°, and a breaking strength of 15.2 MPa.

[0186] In a 60°C water environment, the mass loss of the rapidly degradable polyester modified with tertiary amines was 5.2% in 49 days;

[0187] After tertiary amine-modified rapidly degradable polyester was immersed in a 30 wt% hydrogen peroxide solution at 30°C for 8 h, the number average molecular weight decreased by 3.2%.

[0188] After being immersed in a 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the treated tertiary amine-modified rapidly degradable polyester was further treated in a 60 ° C water environment, and the mass loss in 49 days was 11.3%.

[0189] Example 11

[0190] A method for preparing a tertiary amine-modified rapidly degradable polyester comprises the following steps:

[0191] (1) Preparation of raw materials;

[0192] Tertiary amine: bis(2-hydroxyethyl)amino(trihydroxymethyl)methane;

[0193] Dibasic acid: a mixed acid of 1,9-azelaic acid and terephthalic acid, wherein the molar percentage of 1,9-azelaic acid in the dibasic acid is 60%;

[0194] Diol: 1,4-butanediol;

[0195] Catalyst: tetrabutyl titanate;

[0196] Heat stabilizer: triphenyl phosphate;

[0197] Ether-proof agent: anhydrous sodium acetate;

[0198] (2) After uniformly mixing the tertiary amine, dibasic acid, diol, catalyst, heat stabilizer and anti-ether agent, an esterification reaction is carried out at a pressure of 0.2 MPa and a temperature of 200°C until the water output exceeds 95% of the theoretical value, and then the esterification reaction is terminated; wherein, the amount of tertiary amine added is 0.8% of the molar content of the dibasic acid, the molar ratio of the dibasic acid to the diol is 1:1.3, the amount of catalyst added is 800 ppm by mass of the dibasic acid, the amount of heat stabilizer added is 1000 ppm by mass of the dibasic acid, and the amount of anti-ether agent added is 1000 ppm by mass of the dibasic acid;

[0199] (3) The product after the esterification reaction in step (2) was pre-polycondensed at a temperature of 220°C and a pressure of 8 kPa for 1.5 h, and then polycondensed at a temperature of 220°C and a pressure of 50 Pa for 1.4 h to obtain a tertiary amine-modified rapidly degradable polyester.

[0200] The resulting tertiary amine-modified rapidly degradable polyester had an intrinsic viscosity of 1.10 dL / g, a number-average molecular weight of 48,432 g / mol, a color b value of 9.5, a water static contact angle of 76.8°, and a breaking strength of 15.9 MPa.

[0201] In a 60°C water environment, the mass loss of the rapidly degradable polyester modified with tertiary amine was 14.2% in 49 days;

[0202] After tertiary amine-modified rapidly degradable polyester was immersed in 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the number average molecular weight decreased by 20.2%;

[0203] After being immersed in a 30 wt% hydrogen peroxide solution at 30 ° C for 8 h, the treated tertiary amine-modified rapidly degradable polyester was further treated in a 60 ° C water environment, and the mass loss in 49 days was 29.7%.

Claims

1. An application of a tertiary amine modified rapidly degradable polyester, characterized in that: After oxidation treatment, the tertiary amine-modified rapidly degradable polyester was treated in a 60°C water environment, and the mass loss after 49 days was 11.3-40%. The number average molecular weight of the tertiary amine-modified rapidly degradable polyester decreased by 3-40% after oxidation treatment. The oxidation treatment was performed by immersing in a 30 wt% hydrogen peroxide solution at 30°C for 8 hours. The method for preparing the tertiary amine modified rapidly degradable polyester comprises the following steps: in the presence of a catalyst and an auxiliary agent, tertiary amine, a dibasic acid and a diol are subjected to esterification, pre-polycondensation and polycondensation to prepare the tertiary amine modified rapidly degradable polyester; The structural formula of tertiary amine is RN(CH2CH2OH)2, where R is a side group, and the side group contains at least one hydroxyl group; The amount of tertiary amine added is 0.3-1.2% of the molar content of the dibasic acid.

2. The use of a tertiary amine modified rapidly degradable polyester according to claim 1, characterized in that: The tertiary amine is triethanolamine or bis(2-hydroxyethyl)amino(trihydroxymethyl)methane.

3. The use of a tertiary amine modified rapidly degradable polyester according to claim 1, characterized in that: The dibasic acid is dibasic acid I, or a mixed acid of dibasic acid I and dibasic acid II, dibasic acid I is one or more of 1,4-butanediol, 1,5-pentanedioic acid, 1,6-hexanediol, 1,7-heptanedioic acid, 1,8-octanedioic acid, 1,9-nonanediol and 1,10-decanedioic acid, dibasic acid II is terephthalic acid, and the molar percentage of dibasic acid I in the dibasic acid is 50-60% or 100%; the dihydric alcohol is ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol or 1,6-hexanediol.

4. The use of a tertiary amine modified rapidly degradable polyester according to claim 3, characterized in that: The molar ratio of the dibasic acid to the diol is 1:1.1 to 1.

3.

5. The use of a tertiary amine modified rapidly degradable polyester according to claim 1, characterized in that: The catalyst is tetrabutyl titanate or antimony ethylene glycol, and the added amount of the catalyst is 300-1000ppm of the mass of the dibasic acid.

6. The use of a tertiary amine modified rapidly degradable polyester according to claim 1, characterized in that: The auxiliary agents are heat stabilizer and anti-ether agent, the heat stabilizer is triphenyl phosphate or triphenyl phosphite, the anti-ether agent is anhydrous sodium acetate, and the addition amount of the heat stabilizer and the anti-ether agent is 300-1000ppm of the mass of the dibasic acid.

7. The use of a tertiary amine modified rapidly degradable polyester according to claim 1, characterized in that: The esterification temperature is 160-220°C, the esterification pressure is 0.1-0.6 MPa, and the esterification end condition is that the water output exceeds 95% of the theoretical value; The pre-condensation temperature is 180-240°C, the pre-condensation time is 1-2.5h, and the pre-condensation pressure is 1-10kPa; The polycondensation temperature is 200-260°C, the polycondensation pressure is ≤80Pa, and the polycondensation time is 1-3h.

8. The use of a tertiary amine modified rapidly degradable polyester according to any one of claims 1 to 7, characterized in that: The intrinsic viscosity of the tertiary amine-modified rapidly degradable polyester is 1.06-1.20 dL / g, the number average molecular weight is greater than 30,000 g / mol, the color b value is 3-10, and the water static contact angle is 72°-80.5°.

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