High-heat-resistance and high-toughness copolyester and water cup using same

Abstract

The invention discloses a high-heat-resistance and high-toughness copolyester and a water cup using the same, and relates to the field of polyesters, and the high-heat-resistance and high-toughness copolyester is prepared from the following raw material components: bis (hydroxyethoxy) polycyclic aromatic hydrocarbon, binary acid or ester thereof, and dihydric alcohol; wherein the binary acid is selected from one or more of thiophenedicarboxylic acid, furandicarboxylic acid and terephthalic acid. Dihydroxyethoxy polycyclic aromatic hydrocarbon is introduced into copolyester, intermolecular pi-pi accumulation is formed by a plurality of benzene ring rigid frameworks contained in the dihydroxyethoxy polycyclic aromatic hydrocarbon, chain segment movement energy barriers are improved, the glass-transition temperature of the copolyester reaches 90-170 DEG C, hydroxyethyl and oxygen ether bonds in the structure of the copolyester are combined with alicyclic non-planar conformation of cyclic dihydric alcohol, and therefore the copolyester has the advantages that the copolyester has the good heat resistance, the heat resistance is improved, and the service life of the copolyester is prolonged. 50%-1000% of elongation at break is given to the material, and both high heat resistance and high toughness are achieved; dihydric alcohol is compounded to adjust the flexibility of a molecular chain, the situation that molding is affected by too high melt viscosity is avoided, and ultrasonic-assisted condensation polymerization shortens the reaction time by 30% through the cavitation effect and promotes ductile fracture.

Description

Technical Field

[0001] This invention relates to the field of polyester, specifically to a water cup containing a high heat-resistant and high-toughness copolyester and its applications. Background Technology

[0002] Polyester (PET) is a crystalline polymer with fewer molecular chain segments in its amorphous regions, resulting in high melting points and strong rigidity. Products made from conventional PET materials through screw injection molding often exhibit haziness or whitening in certain areas and a loss of transparency during processing or use due to the material's inherent crystallinity. To obtain highly transparent films or sheets with low impurities and excellent color, conventional polyester must be copolymerized to make it amorphous.

[0003] Traditional copolyester materials such as PET typically have a glass transition temperature below 80°C, making them prone to softening and deformation when containing high-temperature liquids, thus failing to meet the requirements of high-temperature applications. Furthermore, copolyester molecules synthesized from conventional diacids and aliphatic diols lack flexibility, have low elongation at break, and are prone to cracking when subjected to impact or bending, exhibiting poor toughness. Summary of the Invention

[0004] Based on this, the purpose of the present invention is to provide a water cup with a high heat-resistant and high-toughness copolyester and its application, so as to solve the technical problem that general copolyesters are prone to softening and deformation when filled with high-temperature liquids, and cannot meet the requirements of high-temperature use scenarios.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a high heat-resistant and high-toughness copolyester, prepared from the following raw material components: dihydroxyethoxy polycyclic aromatic hydrocarbon, diacid or its esterified form, and diol; wherein the diacid is selected from one or more of thiophene dicarboxylic acid, furan dicarboxylic acid, and terephthalic acid, and the diol includes one or more of cyclic diols and aliphatic diols; the content of the dihydroxyethoxy polycyclic aromatic hydrocarbon is 5 mol%-80 mol% based on the molar amount of the diacid or its esterified form; and the total content of the dihydroxyethoxy polycyclic aromatic hydrocarbon and the diol is 120 mol%-300 mol%.

[0006] The present invention is further configured such that the dihydroxyethoxy polycyclic aromatic hydrocarbon is prepared by reacting bisphenol polycyclic aromatic hydrocarbon with ethylene carbonate, wherein the structure of the dihydroxyethoxy polycyclic aromatic hydrocarbon contains multiple benzene rings and has highly active hydroxyethyl and freely rotating oxygen ether bonds.

[0007] The present invention is further configured such that the cyclic diol is an alicyclic diol, which has greater rigidity and a spatially non-planar structure than ethylene glycol.

[0008] The present invention is further configured such that the glass transition temperature of the high heat-resistant and high-toughness copolyester is 90℃-170℃ and the elongation at break is 50%-1000%.

[0009] A method for preparing a high heat-resistant and high-toughness copolyester includes a copolymerization reaction of a dihydroxyethoxylated polycyclic aromatic hydrocarbon, a diacid or its esterified form, and a diol. The copolymerization reaction is carried out under an inert gas protective atmosphere. During the reaction, the viscosity of the system is monitored in real time by an online viscometer. When the viscosity of the system reaches 0.1-0.3 Pa·s, the temperature is gradually increased. The dihydroxyethoxylated polycyclic aromatic hydrocarbon, the diacid or its esterified form, and the diol are premixed before the reaction. The premixing temperature is 60℃-80℃, the premixing time is 15-30 minutes, and the premixing speed is 200-400 rpm.

[0010] The present invention is further configured such that the copolymerization reaction includes an esterification reaction followed by a polycondensation reaction; the esterification reaction temperature is 180℃-220℃, the reaction time is 2-4 hours, a titanium-based catalyst is used, and the catalyst dosage is 0.05%-0.15% of the total mass of the raw materials; the polycondensation reaction is carried out in two stages, the first stage polycondensation temperature is 240℃-260℃, the vacuum degree is 5-10kPa, and the reaction time is 1-2 hours, and the second stage polycondensation temperature is 260℃-280℃, the vacuum degree is 0.1-1kPa, and the reaction time is 2-4 hours; during the polycondensation reaction, ultrasonic-assisted technology is used, with an ultrasonic power of 200-500W and a frequency of 20-40kHz.

[0011] A water cup, comprising a cup body and a cup lid, wherein both the cup body and the cup lid are injection molded from the aforementioned high heat-resistant and high-toughness copolyester, and the inner wall of the cup body is provided with a nano-coating.

[0012] The present invention is further configured such that the outer side of the cup body is integrally formed with a wave-shaped anti-slip texture.

[0013] The present invention is further configured such that a vent hole is provided on the top of the cup lid, and a waterproof and breathable membrane is provided inside the vent hole.

[0014] The present invention is further configured such that an annular rubber buffer ring is integrally formed at the bottom of the cup body.

[0015] In summary, the present invention has the following main advantages: By introducing dihydroxyethoxy polycyclic aromatic hydrocarbons into the copolyester, the present invention utilizes the rigid skeleton of multiple benzene rings contained therein to form intermolecular π-π stacking, thereby raising the energy barrier of chain segment movement and enabling the glass transition temperature of the copolyester to reach 90℃-170℃. At the same time, the alicyclic non-planar conformation of the hydroxyethyl and oxygen ether bonds in its structure combined with the cyclic diol gives the material a breaking elongation of 50%-1000%, achieving a balance between high heat resistance and high toughness. The compounding of diols adjusts the flexibility of the molecular chain, avoiding excessively high melt viscosity from affecting molding. The ultrasonic-assisted polycondensation reaction shortens the reaction time by 30% through the cavitation effect and promotes tough fracture. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the water cup structure of the present invention.

[0017] In the picture: 1. Cup body; 2. Cup lid; 3. Vent hole. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0019] The embodiments of the present invention will now be described.

[0020] Example 1 The raw materials are prepared as follows: Dihydroxyethoxy polycyclic aromatic hydrocarbons: prepared by reacting bisphenol A with ethylene carbonate, with a molar content of 5 mol.

[0021] Dicarboxylic acid: terephthalic acid, molar amount is calculated as 100 mol.

[0022] Diol: The molar ratio of cyclic diol (1,4-cyclohexanediethanol) to aliphatic diol (ethylene glycol) is 1:1, and the total molar content is 120 mol.

[0023] The preparation steps are as follows: Premixing: Premix the raw materials at 60℃ and 200 rpm for 15 minutes.

[0024] Esterification reaction: under nitrogen protection, the reaction was carried out at 180°C for 2 hours, and the amount of titanium catalyst used was 0.05% of the total mass of the raw materials.

[0025] Polycondensation reaction: The first stage reaction was carried out at 240℃ and 5kPa vacuum for 1 hour; the second stage reaction was carried out at 260℃ and 0.1kPa vacuum for 2 hours, assisted by ultrasonic power of 200W and frequency of 20kHz.

[0026] Performance testing: Glass transition temperature is 90℃; Elongation at break is 50%.

[0027] Example 2 The raw materials are prepared as follows: Dihydroxyethoxy polycyclic aromatic hydrocarbons: molar content is 40 mol.

[0028] Dicarboxylic acid: Thiophene dicarboxylic acid and furan dicarboxylic acid are mixed in a 1:1 ratio, with a molar amount of 100 mol.

[0029] Diol: Cyclic diol (1,4-cyclohexanediethanol), with a total molar content of 200 mol.

[0030] The preparation steps are as follows: Premixing: Premix at 70℃ and 300 rpm for 20 minutes.

[0031] Esterification reaction: Reaction at 200℃ for 3 hours, with a catalyst dosage of 0.1%.

[0032] Polycondensation reaction: First stage reaction at 250℃ and 8kPa for 1.5 hours; second stage reaction at 270℃ and 0.5kPa for 3 hours, with ultrasonic power of 350W and frequency of 30kHz.

[0033] Performance testing: Glass transition temperature is 130℃; Elongation at break is 300%.

[0034] Example 3 The raw materials are prepared as follows: Dihydroxyethoxy polycyclic aromatic hydrocarbons: molar content of 80 mol.

[0035] Dicarboxylic acid: Terephthalic acid and furanyl dicarboxylic acid are mixed in a 3:1 ratio, with a molar amount of 100 mol.

[0036] Diol: The molar ratio of cyclic diol (1,4-cyclohexanediol) to aliphatic diol (1,6-hexanediol) is 2:1, with a total molar content of 300 mol.

[0037] The preparation steps are as follows: Premixing treatment: Premix at 80℃ and 400 rpm for 30 minutes.

[0038] Esterification reaction: reaction at 220℃ for 4 hours, catalyst dosage 0.15%.

[0039] Polycondensation reaction: First stage reaction at 260℃ and 10kPa for 2 hours; second stage reaction at 280℃ and 1kPa for 4 hours, with ultrasonic power of 500W and frequency of 40kHz.

[0040] Performance testing: Glass transition temperature is 170℃; Elongation at break is 1000%.

[0041] Example 4 The raw materials are prepared as follows: Dihydroxyethoxy polycyclic aromatic hydrocarbons: molar content of 60 mol.

[0042] Dicarboxylic acid: Thiophene dicarboxylic acid, molar amount 100 mol.

[0043] Diol: The molar ratio of cyclic diol (1,4-cyclohexanediethanol) to aliphatic diol (ethylene glycol) is 3:2, with a total molar content of 250 mol.

[0044] The preparation steps are as follows: Premixing: Premix at 75℃ and 350 rpm for 25 minutes.

[0045] Esterification reaction: reaction at 190℃ for 3.5 hours, catalyst dosage 0.12%.

[0046] Polycondensation reaction: the first stage reaction was carried out at 245℃ and 6kPa for 1.8 hours; the second stage reaction was carried out at 265℃ and 0.8kPa for 3.5 hours, with ultrasonic power of 400W and frequency of 35kHz.

[0047] Performance testing: Glass transition temperature is 150℃; Elongation at break is 600%.

[0048] Comparative Example 1 The raw materials are prepared as follows: Dihydroxyethoxy polycyclic aromatic hydrocarbons: molar content is 3 mol.

[0049] Dicarboxylic acid: terephthalic acid, molar amount 100 mol.

[0050] Diol: Ethylene glycol, total molar content 120 mol.

[0051] The preparation steps are as follows: Premixing: Premix at 60℃ and 200 rpm for 15 minutes.

[0052] Esterification reaction: react at 180℃ for 2 hours, with a catalyst dosage of 0.05%.

[0053] Polycondensation reaction: the first stage reaction was carried out at 240℃ and 5kPa for 1 hour; the second stage reaction was carried out at 260℃ and 0.1kPa for 2 hours, without ultrasonic assistance.

[0054] Performance testing: Glass transition temperature is 70℃; Elongation at break is 40%.

[0055] Comparative Example 2 The raw materials are prepared as follows: Dihydroxyethoxy polycyclic aromatic hydrocarbons: molar content is 40 mol.

[0056] Dicarboxylic acid: Thiophene dicarboxylic acid, molar amount 100 mol.

[0057] Diol: Ethylene glycol, total molar content 200 mol.

[0058] The preparation steps are as follows: Premixing: Premix at 70℃ and 300 rpm for 20 minutes.

[0059] Esterification reaction: Reaction at 200℃ for 3 hours, with a catalyst dosage of 0.1%.

[0060] Polycondensation reaction: the first stage reaction was carried out at 250℃ and 8kPa for 1.5 hours; the second stage reaction was carried out at 270℃ and 0.5kPa for 3 hours, without ultrasonic assistance.

[0061] Performance testing: Glass transition temperature is 110℃; Elongation at break is 200%.

[0062] Comparative Example 3 The raw materials are prepared as follows: Dihydroxyethoxy polycyclic aromatic hydrocarbons: molar content of 60 mol.

[0063] Dicarboxylic acid: Thiophene dicarboxylic acid, molar amount 100 mol.

[0064] Diol: The molar ratio of cyclic diol (1,4-cyclohexanediethanol) to ethylene glycol is 3:2, with a total molar content of 250 mol.

[0065] The preparation steps are as follows: Premixing: Premix at 75℃ and 350 rpm for 25 minutes.

[0066] Esterification reaction: reaction at 190℃ for 3.5 hours, catalyst dosage 0.12%.

[0067] Polycondensation reaction: the first stage reaction was carried out at 245℃ and 6kPa for 1.8 hours; the second stage reaction was carried out at 265℃ and 0.8kPa for 3.5 hours, without ultrasonic assistance.

[0068] Performance testing: Glass transition temperature is 135℃; Elongation at break is 450%.

[0069] Comparative Example 4 The raw materials are prepared as follows: Dihydroxyethoxy polycyclic aromatic hydrocarbons: molar content of 85 mol.

[0070] Dicarboxylic acid: terephthalic acid, molar amount 100 mol.

[0071] Diol: Cyclic diol (1,4-cyclohexanediethanol), total molar content 320 mol.

[0072] The preparation steps are as follows: Premixing treatment: Premix at 80℃ and 400 rpm for 30 minutes.

[0073] Esterification reaction: reaction at 220℃ for 4 hours, catalyst dosage 0.15%.

[0074] Polycondensation reaction: First stage reaction at 260℃ and 10kPa for 2 hours; second stage reaction at 280℃ and 1kPa for 4 hours, with ultrasonic power of 500W and frequency of 40kHz.

[0075] Performance testing: The glass transition temperature is 180℃, but the viscosity of the system is out of control and cannot be molded normally.

[0076] Data Comparison Table

[0077] In the analysis of the above examples and comparative examples, the content of dihydroxyethoxy polycyclic aromatic hydrocarbons has a significant impact. When the content increases from 5 mol% to 80 mol%, the temperature Tg increases from 90°C to 170°C. This is attributed to the rigid skeleton of the benzene ring in the polycyclic aromatic hydrocarbon structure forming intermolecular π-π stacking, which increases the energy barrier for chain segment movement.

[0078] When the content exceeds 80 mol%, as in Comparative Example 4, the excessive rigidity of the molecular chain leads to uncontrolled melt viscosity, making injection molding impossible. This verifies that 80 mol% is the upper limit.

[0079] The alicyclic structure of CHDM enables the molecular chain to form a non-planar conformation. In Example 2, the elongation at break was increased by 50% compared with Comparative Example 2, demonstrating that steric hindrance can improve the flexibility of the chain segment.

[0080] In Examples 1, 3, and 4, the combination of cyclic and aliphatic diols maintained an elongation at break of ≥50% at Tg≥90℃, which is superior to the single-type diol system.

[0081] Introducing 200-500W ultrasound shortens the polycondensation reaction time by 30%, and the cavitation effect promotes molecular chain diffusion and end-group collision.

[0082] Scanning electron microscopy revealed that the fracture surface of the ultrasonically treated copolyester exhibited ductile fracture characteristics, while it showed brittle fracture without assistance.

[0083] The water cup consists of a cup body 1 and a cup lid 2. Both the cup body 1 and the cup lid 2 are injection molded from high heat-resistant and high-toughness copolyester. The inner wall of the cup body 1 is coated with a nano-coating, and the outer side is integrally molded with a wave-shaped anti-slip texture with a texture height of 1-2mm and a spacing of 5-8mm to enhance the grip.

[0084] The top of the cup lid 2 has a 5mm diameter vent hole 3, and a waterproof and breathable membrane is embedded in the vent hole 3. The waterproof and breathable membrane can be a polytetrafluoroethylene waterproof and breathable membrane, which can balance the internal and external air pressure and prevent liquid leakage.

[0085] The bottom of the cup body 1 is integrally molded with a ring-shaped rubber buffer ring, which can reduce noise and vibration when the cup is placed.

[0086] Although embodiments of the present invention have been shown and described, these specific embodiments are merely explanations of the invention and are not intended to limit it. The specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. After reading this specification, those skilled in the art may make modifications, substitutions, and variations to the embodiments as needed without departing from the principles and spirit of the invention, but such modifications, substitutions, and variations are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. A high heat-resistant and high-toughness copolyester, characterized in that, It is prepared from the following components: dihydroxyethoxy polycyclic aromatic hydrocarbon, diacid or its esterified form, and diol; wherein the diacid is selected from one or more of thiophene dicarboxylic acid, furan dicarboxylic acid, and terephthalic acid, and the diol includes one or more of cyclic diols and aliphatic diols; the content of the dihydroxyethoxy polycyclic aromatic hydrocarbon is 5 mol%-80 mol% based on the molar amount of the diacid or its esterified form; and the total content of the dihydroxyethoxy polycyclic aromatic hydrocarbon and the diol is 120 mol%-300 mol%.

2. The high heat-resistant and high-toughness copolyester according to claim 1, characterized in that: The dihydroxyethoxy polycyclic aromatic hydrocarbon is prepared by reacting bisphenol polycyclic aromatic hydrocarbon with ethylene carbonate. The structure of the dihydroxyethoxy polycyclic aromatic hydrocarbon contains multiple benzene rings and has highly active hydroxyethyl groups and freely rotating oxygen ether bonds.

3. The high heat-resistant and high-toughness copolyester according to claim 1, characterized in that: The cyclic diol is an alicyclic diol, which has greater rigidity and a non-planar spatial structure than ethylene glycol.

4. The high heat-resistant and high-toughness copolyester according to claim 1, characterized in that: The high heat-resistant and high-toughness copolyester has a glass transition temperature of 90℃-170℃ and an elongation at break of 50%-1000%.

5. A method for preparing a high heat-resistant and high-toughness copolyester, characterized in that, The reaction involves copolymerizing a dihydroxyethoxylated polycyclic aromatic hydrocarbon, a diacid or its esterified form, and a diol. The copolymerization reaction is carried out under an inert gas atmosphere. During the reaction, the viscosity of the system is monitored in real time using an online viscometer. When the system viscosity reaches 0.1-0.3 Pa·s, the temperature is gradually increased. The dihydroxyethoxylated polycyclic aromatic hydrocarbon, the diacid or its esterified form, and the diol are premixed before the reaction. The premixing temperature is 60℃-80℃, the premixing time is 15-30 minutes, and the premixing speed is 200-400 rpm.

6. The method for preparing a high heat-resistant and high-toughness copolyester according to claim 5, characterized in that, The copolymerization reaction includes an esterification reaction followed by a polycondensation reaction. The esterification reaction is carried out at a temperature of 180℃-220℃ for 2-4 hours, using a titanium-based catalyst at a concentration of 0.05%-0.15% of the total raw material mass. The polycondensation reaction is carried out in two stages: the first stage is carried out at a temperature of 240℃-260℃ under a vacuum of 5-10 kPa for 1-2 hours, and the second stage is carried out at a temperature of 260℃-280℃ under a vacuum of 0.1-1 kPa for 2-4 hours. During the polycondensation reaction, ultrasonic-assisted technology is used with an ultrasonic power of 200-500 W and a frequency of 20-40 kHz.

7. A water cup, characterized in that, The water cup is composed of a cup body (1) and a cup lid (2), and both the cup body (1) and the cup lid (2) are injection molded from the high heat-resistant and high toughness copolyester described in claims 1-4. The inner wall of the cup body (1) is provided with a nano-coating.

8. The water cup according to claim 7, characterized in that, The outer side of the cup body (1) is integrally formed with a wave-shaped anti-slip texture.

9. The water cup according to claim 7, characterized in that, The top of the cup lid (2) is provided with a vent hole, and a waterproof and breathable membrane is provided inside the vent hole.

10. The water cup according to claim 7, characterized in that, The bottom of the cup body (1) is integrally formed with an annular rubber buffer ring.

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