High-heat-resistance polyester material and preparation method thereof

Abstract

The invention discloses a high-heat-resistance polyester material and a preparation method thereof. The high-heat-resistance polyester material comprises the following raw materials in parts by weight: 100 parts of binary acid, 100-120 parts of dihydric alcohol, 5-10 parts of modified trimethylolpropane monoallyl ether and 3-8 parts of a titanium catalyst. Wherein the modified trimethylolpropane monoallyl ether comprises one primary hydroxyl group, one allyl ether group and two methacrylate groups; in the polyester generation process, primary hydroxyl participates in polyester condensation polymerization, it is ensured that molecules are embedded into a main chain, allyl ether groups slowly initiate cross-linking points when heated, two methacrylate groups serve as high-reaction-activity double bonds, free radicals of the methacrylate groups are very active, the methacrylate groups can be rapidly added with other double bonds, the chain growth rate is increased, and therefore the molecular weight is reduced. Furthermore, a high-molecular-weight polymer chain can be quickly formed, the crosslinking time is shortened, the crosslinking density is increased, and the heat resistance of the polyester material is further improved.

Description

Technical Field

[0001] This invention relates to the field of polyester materials technology, specifically to a high heat-resistant polyester material and its preparation method. Background Technology

[0002] Polyester materials, as an important class of polymer materials, have been widely used in fields such as fibers, packaging, electronics, and the automotive industry due to their excellent mechanical properties, chemical stability, and processing performance. Among them, polyethylene terephthalate (PET) and polybutylene terephthalate (PBT) are the two most widely used polyester materials.

[0003] In the packaging industry, there is an extremely high demand for packaging bottles made of polyester materials. For products with poor weather resistance, such as food and cosmetics, the heat resistance requirements for packaging bottles are extremely high. Currently, to overcome the heat resistance bottleneck of traditional polyester materials, methods such as copolymer modification, glass fiber reinforcement, nanofiller composites, and applying an organosilicon coating to the outer surface of polyester materials can be used to improve their heat resistance. However, although these methods can improve the heat resistance of polyester materials to a certain extent, their high process and raw material costs make them difficult to commercialize. Summary of the Invention

[0004] One of the objectives of this invention is to provide a high heat-resistant polyester material to solve the following technical problems: How to improve the heat resistance of polyester materials at a low cost.

[0005] The second objective of this invention is to provide a preparation method for preparing the above-mentioned high heat-resistant polyester material.

[0006] The objective of this invention can be achieved through the following technical solutions: In a first aspect, the present invention discloses a high heat-resistant polyester material comprising the following raw materials in parts by weight: 100 parts of diacid, 100-120 parts of diol, and 5-10 parts of modified trimethylolpropane monoallyl ether; wherein the modified trimethylolpropane monoallyl ether comprises one primary hydroxyl group, one allyl ether group, and two methacrylate groups.

[0007] Preferably, the high heat-resistant polyester material comprises the following raw materials in parts by weight: 100 parts of diacid, 114 parts of diol, and 8 parts of modified trimethylolpropane monoallyl ether.

[0008] Preferably, the dicarboxylic acid is a mixture of isophthalic acid, phthalic anhydride, and sebacic acid in a mass ratio of 2:1:1.

[0009] Preferably, the diol is a mixture of ethylene glycol and neopentyl glycol in a mass ratio of 2:1.

[0010] Preferably, the preparation method of the modified trimethylolpropane monoallyl ether includes the following steps: Step 1: Mix trimethylolpropane monoallyl ether, ethylene carbonate and tetrabutylammonium bromide, heat to 80°C under nitrogen protection and stir for 4-5 hours, then distill under reduced pressure to obtain a pale yellow viscous liquid; during this process, ethylene carbonate is grafted onto the two free hydroxyl groups of trimethylolpropane monoallyl ether to form cyclic carbonate groups. Step 2: Dissolve the pale yellow viscous liquid in tetrahydrofuran, then add iminodiacetic anhydride and stir until homogeneous. After cooling to 0°C, add triethylamine dropwise as a catalyst, then heat to 25°C and react for 10-12 hours. After filtration and rotary evaporation, the product is obtained. During this process, the cyclic carbonate group reacts with the iminodiacetic anhydride, and the cyclic carbonate group opens the ring to generate two carboxyl groups. Step 3: Mix the product, glycidyl methacrylate, and 4-methoxyphenol, add triphenylphosphine, heat to 80℃ and react for 3-4 hours, then cool to room temperature, wash, and distill under reduced pressure to obtain modified trimethylolpropane monoallyl ether; in this process, the two carboxyl groups combine with the methacrylate groups in 4-methoxyphenol to generate two methacrylate groups.

[0011] Preferably, in step 1, the molar ratio of trimethylolpropane monoallyl ether to ethylene carbonate is 1:2.2, and the molar amount of tetrabutylammonium bromide accounts for 0.3-0.7% of the total molar amount of trimethylolpropane monoallyl ether and ethylene carbonate. More preferably, the molar amount of the tetrabutylammonium bromide accounts for 0.5% of the total molar amount of trimethylolpropane monoallyl ether and ethylene carbonate.

[0012] Preferably, in step 2, the molar ratio of the viscous liquid to iminodiacetic anhydride is 1:(1.02-1.1), and the molar amount of triethylamine is 0.1-0.2% of the total molar amount of the viscous liquid and iminodiacetic anhydride. More preferably, the molar amount of triethylamine is 0.15% of the total molar amount of the viscous liquid and iminodiacetic anhydride.

[0013] Preferably, in step 3, the molar ratio of the product, glycidyl methacrylate, and 4-methoxyphenol is 1:2.2:0.5, and the molar amount of triphenylphosphine is 0.1-0.4% of the total molar amount of the product, glycidyl methacrylate, and 4-methoxyphenol. More preferably, the molar amount of the triphenylphosphine is 0.2% of the total molar amount of the product, glycidyl methacrylate and 4-methoxyphenol.

[0014] Preferably, in step 3, the washing method is to repeatedly wash with a 5% Na2CO3 solution 3-5 times.

[0015] Preferably, in step 3, the vacuum distillation method is as follows: distilling an organic phase at 70°C and 1 mmHg for 1-2 hours; More preferably, the organic phase is toluene.

[0016] Secondly, the present invention also discloses a method for preparing a high heat-resistant polyester material, which is used to prepare the high heat-resistant polyester material as described above, comprising the following steps: Step 1: Under nitrogen protection, 100 parts of diacid, 100-120 parts of diol and 5-10 parts of modified trimethylolpropane monoallyl ether are placed in a reaction vessel, mixed, heated and stirred. When heated to 140-150℃, a titanium-based catalyst is added, and the temperature of the distilled water is controlled at 95-105℃ to carry out the esterification reaction; wherein, the modified trimethylolpropane monoallyl ether comprises 1 primary hydroxyl group, 1 allyl ether group and 2 methacrylate groups; Step 2: Gradually heat the reactor to 240-250℃ and maintain this temperature to continue the reaction. Control the temperature of the distilled water to gradually decrease until the theoretical output water from esterification is reached. Step 3: Evacuate the reactor to 500Pa and continue the reaction for 40-60 minutes, then evacuate to 100Pa and heat to 260-270℃ to continue the reaction for 1 hour to obtain a high heat-resistant polyester material.

[0017] Preferably, the amount of the titanium-based catalyst is 0.01-0.02% of the amount of the dicarboxylic acid; More preferably, the amount of the titanium-based catalyst is 0.05% of the amount of the dicarboxylic acid.

[0018] Preferably, the titanium-based catalyst is tetrabutyl titanate.

[0019] The beneficial effects of this invention are: In the high heat-resistant polyester material of this invention, the polyester material is mainly generated through the reaction of diacid and diol. During the reaction process, modified trimethylolpropane monoallyl ether is introduced to replace part of the diol. The modified trimethylolpropane monoallyl ether contains one primary hydroxyl group, one allyl ether group, and two methacrylate groups. During the polyester generation process, the primary hydroxyl group participates in the polyester polycondensation reaction to ensure that the molecule is embedded in the main chain. The allyl ether group slowly initiates crosslinking points when heated, while the two methacrylate groups, as highly reactive double bonds, have very active free radicals that can quickly add to other double bonds, increasing the chain growth rate and thus rapidly forming high molecular weight polymer chains, shortening the crosslinking time, and increasing the crosslinking density. At the same time, the weight ratio of diacid, diol, and modified trimethylolpropane monoallyl ether is limited to ensure that each component plays its most effective role, thereby improving the heat resistance of the polyester material. Detailed Implementation

[0020] The specific embodiments of the present invention will be described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0021] The terminology used in the embodiments of this application is for the purpose of describing particular implementations only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the implementations of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0022] It should be understood that in the various embodiments of this application, the sequence number of each process does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the implementation regulations of this application.

[0023] The weights of the relevant components mentioned in the embodiments of this application can refer not only to the specific content of each component, but also to the proportional relationship between the weights of the components. Therefore, any scaling up or down of the content of the relevant components according to the embodiments of this application is within the scope disclosed in the embodiments of this application. Specifically, the mass described in the embodiments of this application can be a mass unit known in the chemical industry, such as μg, mg, g, or kg.

[0024] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0025] Unless otherwise specified, all raw materials, reagents, instruments, and equipment used in this application are commercially available or can be prepared using existing methods.

[0026] Preparation Example 1

[0027] The modified trimethylolpropane monoallyl ether was prepared by following these steps in sequence: Step 1: In a reactor, 1 mol of trimethylolpropane monoallyl ether, 2.2 mol of ethylene carbonate and 0.016 mol of tetrabutylammonium bromide are mixed and heated to 80°C under nitrogen protection and stirred for 4.5 h. Then, the mixture is distilled under reduced pressure at 60°C and 10 mmHg to obtain a pale yellow viscous liquid. Step 2: In a beaker, dissolve the pale yellow viscous liquid completely in 250 mL of tetrahydrofuran, then add 1.05 mol of iminodiacetic anhydride and stir until homogeneous. After cooling to 0°C in a water bath, add 0.003 mol of triethylamine as a catalyst, then heat to 25°C and react for 11 h. After filtration and rotary evaporation, the product is obtained. Step 3: In the reactor, all the product, 2.2 mol of glycidyl methacrylate, and 0.5 mol of 4-methoxyphenol were mixed, and 0.007 mol of triphenylphosphine was added. The mixture was heated to 80 °C and reacted for 3.5 h. Then it was cooled to room temperature, washed three times with a 5% Na2CO3 solution, and distilled with toluene at 70 °C and 1 mmHg under reduced pressure for 1.5 h to obtain modified trimethylolpropane monoallyl ether.

[0028] By repeating the above method, sufficient quantities of modified trimethylolpropane monoallyl ether can be obtained.

[0029] Preparation Example 2

[0030] The modified trimethylolpropane monoallyl ether was prepared by replacing the amount of iminodiacetic anhydride with 1.02 mol in step 2, while keeping the other steps and conditions the same, and finally obtained the modified trimethylolpropane monoallyl ether.

[0031] Preparation Example 3

[0032] The modified trimethylolpropane monoallyl ether was prepared by replacing the amount of iminodiacetic anhydride with 1.1 mol in step 2, while keeping the other steps and conditions the same, and finally obtained the modified trimethylolpropane monoallyl ether.

[0033] Comparative Preparation Example 1

[0034] The preparation of modified trimethylolpropane monoallyl ether differs from that in Preparation Example 1 only in that step 3 is omitted, and the product obtained in step 2 is used as the modified trimethylolpropane monoallyl ether.

[0035] Example 1

[0036] The preparation of high heat-resistant polyester materials is carried out in the following steps: Step 1: Under nitrogen protection, 500g of isophthalic acid, 250g of phthalic anhydride, 250g of sebacic acid, 760g of ethylene glycol, 380g of neopentyl glycol, and 80g of the modified trimethylolpropane monoallyl ether of Preparation Example 1 were placed in a reaction vessel, mixed, heated and stirred. When heated to 140-150℃, 0.15g of tetrabutyl titanate was added, and the temperature of the distilled water was controlled at 100℃ to carry out the esterification reaction. Step 2: Gradually heat the reactor to 245°C and maintain this temperature to continue the reaction. Control the temperature of the distilled water to gradually decrease until the theoretical output water from esterification is reached. Step 3: Evacuate the reactor to 500Pa and continue the reaction for 50 minutes, then evacuate to 100Pa and heat to 265℃ to continue the reaction for 1 hour to obtain a high heat-resistant polyester material.

[0037] Example 2

[0038] The preparation of high heat-resistant polyester materials is carried out in the following steps: Step 1: Under nitrogen protection, 500g of isophthalic acid, 250g of phthalic anhydride, 250g of sebacic acid, 668g of ethylene glycol, 334g of neopentyl glycol, and 50g of the modified trimethylolpropane monoallyl ether of Preparation Example 1 were placed in a reaction vessel, mixed, heated and stirred. When heated to 140-150℃, 0.15g of tetrabutyl titanate was added, and the temperature of the distilled water was controlled at 100℃ to carry out the esterification reaction. Step 2: Gradually heat the reactor to 245°C and maintain this temperature to continue the reaction. Control the temperature of the distilled water to gradually decrease until the theoretical output water from esterification is reached. Step 3: Evacuate the reactor to 500Pa and continue the reaction for 50 minutes, then evacuate to 100Pa and heat to 265℃ to continue the reaction for 1 hour to obtain a high heat-resistant polyester material.

[0039] Example 3

[0040] The preparation of high heat-resistant polyester materials is carried out in the following steps: Step 1: Under nitrogen protection, 500g of isophthalic acid, 250g of phthalic anhydride, 250g of sebacic acid, 800g of ethylene glycol, 400g of neopentyl glycol, and 100g of the modified trimethylolpropane monoallyl ether of Preparation Example 1 were placed in a reaction vessel, mixed, heated and stirred. When heated to 140-150℃, 0.15g of tetrabutyl titanate was added, and the temperature of the distilled water was controlled at 100℃ to carry out the esterification reaction. Step 2: Gradually heat the reactor to 245°C and maintain this temperature to continue the reaction. Control the temperature of the distilled water to gradually decrease until the theoretical output water from esterification is reached. Step 3: Evacuate the reactor to 500Pa and continue the reaction for 50 minutes, then evacuate to 100Pa and heat to 265℃ to continue the reaction for 1 hour to obtain a high heat-resistant polyester material.

[0041] Example 4

[0042] The high heat-resistant polyester material was prepared by replacing the modified trimethylolpropane monoallyl ether of Preparation Example 1 with the modified trimethylolpropane monoallyl ether of Preparation Example 2, while keeping the other steps and conditions the same, and finally the high heat-resistant polyester material was obtained.

[0043] Example 5

[0044] The high heat-resistant polyester material was prepared by replacing the modified trimethylolpropane monoallyl ether of Preparation Example 1 with the modified trimethylolpropane monoallyl ether of Preparation Example 3, while keeping the other steps and conditions the same, and finally the high heat-resistant polyester material was obtained.

[0045] Comparative Example 1

[0046] The high heat-resistant polyester material was prepared by replacing the modified trimethylolpropane monoallyl ether of Preparation Example 1 with the modified trimethylolpropane monoallyl ether of Comparative Preparation Example 1, while keeping the other steps and conditions the same, and finally the polyester material was obtained.

[0047] Comparative Example 2

[0048] The high heat-resistant polyester material was prepared by replacing the modified trimethylolpropane monoallyl ether of Preparation Example 1 with ethylene glycol, while keeping the other steps and conditions the same, and finally obtaining the polyester material.

[0049] The heat resistance properties of the polyester materials prepared in Examples 1-5 and Comparative Examples 1-2 were tested. The test method was as follows: the polyester material to be tested was made into a sample with a size of 80mm×10mm×4mm by pressing process. The sample was placed in a three-point bending fixture, a fixed load of 1.8MPa was applied, and the temperature was increased at a constant rate of 2℃ / min. The temperature at which the deformation of the sample reached 0.25mm was recorded as the heat distortion temperature.

[0050] The test results are listed in Table 1, as follows: Table 1

[0051] Analysis of the data in Table 1 shows that the heat distortion temperature of the polyester materials in Examples 1-5 is significantly higher than that in Comparative Examples 1-2, indicating that the polyester materials of the present invention have stronger heat resistance.

[0052] Specifically, in Comparative Example 1, the polyester material incorporated the modified trimethylolpropane monoallyl ether of Comparative Preparation Example 1, which did not generate methacrylate groups (step 3 was omitted), thus having little effect on increasing the crosslinking density, resulting in a decrease in the heat distortion temperature. In Comparative Example 2, the modified trimethylolpropane monoallyl ether was directly replaced with a diol (ethylene glycol), thus losing the crosslinking-promoting effect of the modified trimethylolpropane monoallyl ether, and therefore the heat distortion temperature decreased accordingly. Based on this, it can be shown that the polyester material of the present invention, by incorporating the modified trimethylolpropane monoallyl ether of the present invention, enhances the crosslinking density of the polyester material, thereby improving its heat resistance.

[0053] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A highly heat resistant polyester material, characterized by, The raw materials include 100 parts of binary acid, 100-120 parts of binary alcohol and 5-10 parts of modified trimethylolpropane monoallyl ether. The modified trimethylolpropane monoallyl ether comprises one primary hydroxyl group, one allyl ether group and two methacrylate groups.

2. The high heat resistant polyester material according to claim 1, wherein, The binary acid is a mixture of isophthalic acid, phthalic anhydride and succinic acid in a mass ratio of 2:1:

1.

3. The high heat resistant polyester material according to claim 1, wherein, The binary alcohol is a mixture of ethylene glycol and neopentyl glycol in a mass ratio of 2:

1.

4. The high heat resistant polyester material according to claim 1, wherein, The preparation method of the modified trimethylolpropane monoallyl ether comprises the following steps: In step 1, the trimethylolpropane monoallyl ether, ethylene carbonate and tetrabutylammonium bromide are mixed, heated to 80℃ under nitrogen protection, stirred for 4-5h, and then distilled under reduced pressure to obtain a yellowish viscous liquid. In step 2, the yellowish viscous liquid is dissolved in tetrahydrofuran, then imino diacetic anhydride is added and stirred uniformly, triethylamine is added dropwise after cooling to 0℃, then heated to 25℃ for reaction for 10-12h, filtered and rotary evaporated to obtain the product. In step 3, the product, glycidyl methacrylate and 4-methoxyphenol are mixed, then triphenylphosphine is added, heated to 80℃ for reaction for 3-4h, then cooled to room temperature, washed and distilled under reduced pressure to obtain the modified trimethylolpropane monoallyl ether.

5. The high heat resistant polyester material according to claim 4, wherein, In step 1, the molar ratio of the trimethylolpropane monoallyl ether to ethylene carbonate is 1:2.2, and the molar amount of tetrabutylammonium bromide accounts for 0.3-0.7% of the total molar amount of the trimethylolpropane monoallyl ether and ethylene carbonate.

6. The high heat resistant polyester material according to claim 4, wherein, In step 2, the molar ratio of the viscous liquid to imino diacetic anhydride is 1:(1.02-1.1), and the molar amount of triethylamine accounts for 0.1-0.2% of the total molar amount of the viscous liquid and imino diacetic anhydride.

7. The high heat resistant polyester material according to claim 4, wherein, In step 3, the molar ratio of the product, glycidyl methacrylate and 4-methoxyphenol is 1:2.2:0.5, and the molar amount of triphenylphosphine accounts for 0.1-0.4% of the total molar amount of the product, glycidyl methacrylate and 4-methoxyphenol.

8. The high heat resistant polyester material according to claim 4, wherein, In step 3, the washing method is repeated washing 3-5 times with 5% Na2CO3 solution.

9. The high heat resistant polyester material according to claim 4, wherein, In step 3, the method of distillation under reduced pressure is that the organic phase is distilled at 70℃ and 1mmHg for 1-2h.

10. A process for the preparation of a high heat resistant polyester material for the preparation of a high heat resistant polyester material according to any one of claims 1 to 9, characterized in that, The method comprises the following steps: In step 1, the trimethylolpropane monoallyl ether, ethylene carbonate and tetrabutylammonium bromide are mixed, heated to 80℃ under nitrogen protection, stirred for 4-5h, and then distilled under reduced pressure to obtain a yellowish viscous liquid. In step 2, the yellowish viscous liquid is dissolved in tetrahydrofuran, then imino diacetic anhydride is added and stirred uniformly, triethylamine is added dropwise after cooling to 0℃, then heated to 25℃ for reaction for 10-12h, filtered and rotary evaporated to obtain the product. In step 3, the product, glycidyl methacrylate and 4-methoxyphenol are mixed, then triphenylphosphine is added, heated to 80℃ for reaction for 3-4h, then cooled to room temperature, washed and distilled under reduced pressure to obtain the modified trimethylolpropane monoallyl ether. In step 1, the molar ratio of the trimethylolpropane monoallyl ether to ethylene carbonate is 1:2.2, and the molar amount of tetrabutylammonium bromide accounts for 0.3-0.7% of the total molar amount of the trimethylolpropane monoallyl ether and ethylene carbonate. In step 2, the molar ratio of the viscous liquid to imino diacetic anhydride is 1:(1.02-1.1), and the molar amount of triethylamine accounts for 0.1-0.2% of the total molar amount of the viscous liquid and imino diacetic anhydride. In step 3, the molar ratio of the product, glycidyl methacrylate and 4-methoxyphenol is 1:2.2:0.5, and the molar amount of triphenylphosphine accounts for 0.1-0.4% of the total molar amount of the product, glycidyl methacrylate and 4-methoxyphenol. In step 3, the washing method is repeated washing 3-5 times with 5% Na2CO3 solution. In step 3, the method of distillation under reduced pressure is that the organic phase is distilled at 70℃ and 1mmHg for 1-2h. The method comprises the following steps: In step 1, the trimethylolpropane monoallyl ether, ethylene carbonate and tetrabutylammonium bromide are mixed, heated to 80℃ under nitrogen protection, stirred for 4-5h, and then distilled under reduced pressure to obtain a yellowish viscous liquid. In step 2, the yellowish viscous liquid is dissolved in tetrahydrofuran, then imino diacetic anhydride is added and stirred uniformly, triethylamine is added dropwise after cooling to 0℃, then heated to 25℃ for reaction for 10-12h, filtered and rotary evaporated to obtain the product. In step 3, the product, glycidyl methacrylate and 4-methoxyphenol are mixed, then triphenylphosphine is added, heated to 80℃ for reaction for 3-4h, then cooled to room temperature, washed and distilled under reduced pressure to obtain the modified trimethylolpropane monoallyl ether. Step three, vacuumize the reactor to 500Pa and continue the reaction for 40-60min, vacuumize to 100Pa, and then heat to 260-270℃ and continue the reaction for 1h to obtain the high heat-resistant polyester material.

Images