CN117887049A - Polyarylate based on 1, 2-tetra (4-hydroxyphenyl) ethane and preparation method thereof - Google Patents
Polyarylate based on 1, 2-tetra (4-hydroxyphenyl) ethane and preparation method thereof Download PDFInfo
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- CN117887049A CN117887049A CN202311802066.8A CN202311802066A CN117887049A CN 117887049 A CN117887049 A CN 117887049A CN 202311802066 A CN202311802066 A CN 202311802066A CN 117887049 A CN117887049 A CN 117887049A
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- hydroxyphenyl
- ethane
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- tetrakis
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- HXDOZKJGKXYMEW-UHFFFAOYSA-N 4-ethylphenol Chemical compound CCC1=CC=C(O)C=C1 HXDOZKJGKXYMEW-UHFFFAOYSA-N 0.000 title claims abstract description 20
- 229920001230 polyarylate Polymers 0.000 title claims abstract description 17
- 238000002360 preparation method Methods 0.000 title claims abstract description 8
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N Hydroquinone Chemical compound OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 claims abstract description 40
- KKEYFWRCBNTPAC-UHFFFAOYSA-N Terephthalic acid Chemical compound OC(=O)C1=CC=C(C(O)=O)C=C1 KKEYFWRCBNTPAC-UHFFFAOYSA-N 0.000 claims abstract description 38
- FJKROLUGYXJWQN-UHFFFAOYSA-N 4-hydroxybenzoic acid Chemical compound OC(=O)C1=CC=C(O)C=C1 FJKROLUGYXJWQN-UHFFFAOYSA-N 0.000 claims abstract description 33
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 20
- 229940090248 4-hydroxybenzoic acid Drugs 0.000 claims abstract description 17
- KAUQJMHLAFIZDU-UHFFFAOYSA-N 6-Hydroxy-2-naphthoic acid Chemical compound C1=C(O)C=CC2=CC(C(=O)O)=CC=C21 KAUQJMHLAFIZDU-UHFFFAOYSA-N 0.000 claims abstract description 17
- 238000006068 polycondensation reaction Methods 0.000 claims abstract description 16
- 239000000178 monomer Substances 0.000 claims abstract description 14
- WFDIJRYMOXRFFG-UHFFFAOYSA-N Acetic anhydride Chemical compound CC(=O)OC(C)=O WFDIJRYMOXRFFG-UHFFFAOYSA-N 0.000 claims abstract description 12
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 10
- 239000007790 solid phase Substances 0.000 claims abstract description 10
- 238000006116 polymerization reaction Methods 0.000 claims abstract description 8
- 238000000034 method Methods 0.000 claims abstract description 7
- 239000000843 powder Substances 0.000 claims abstract description 4
- 229920000728 polyester Polymers 0.000 claims description 37
- 238000006243 chemical reaction Methods 0.000 claims description 7
- 239000000463 material Substances 0.000 claims description 5
- XBNGYFFABRKICK-UHFFFAOYSA-N 2,3,4,5,6-pentafluorophenol Chemical compound OC1=C(F)C(F)=C(F)C(F)=C1F XBNGYFFABRKICK-UHFFFAOYSA-N 0.000 claims description 3
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 claims description 3
- 238000001035 drying Methods 0.000 claims description 3
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims description 3
- IZUPBVBPLAPZRR-UHFFFAOYSA-N pentachloro-phenol Natural products OC1=C(Cl)C(Cl)=C(Cl)C(Cl)=C1Cl IZUPBVBPLAPZRR-UHFFFAOYSA-N 0.000 claims description 3
- 238000007599 discharging Methods 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 claims 1
- 239000000835 fiber Substances 0.000 abstract description 19
- 238000009987 spinning Methods 0.000 abstract description 7
- 229920005989 resin Polymers 0.000 abstract description 6
- 239000011347 resin Substances 0.000 abstract description 6
- 238000004132 cross linking Methods 0.000 abstract description 5
- 239000000155 melt Substances 0.000 abstract description 3
- 229920006158 high molecular weight polymer Polymers 0.000 abstract description 2
- 239000004974 Thermotropic liquid crystal Substances 0.000 abstract 1
- 125000003118 aryl group Chemical group 0.000 description 31
- 230000000052 comparative effect Effects 0.000 description 11
- 238000002844 melting Methods 0.000 description 9
- 230000008018 melting Effects 0.000 description 9
- 238000012360 testing method Methods 0.000 description 4
- 238000010128 melt processing Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- 239000004973 liquid crystal related substance Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229920001225 polyester resin Polymers 0.000 description 2
- 239000004645 polyester resin Substances 0.000 description 2
- 229940094537 polyester-10 Drugs 0.000 description 2
- 125000005274 4-hydroxybenzoic acid group Chemical group 0.000 description 1
- 241001391944 Commicarpus scandens Species 0.000 description 1
- 238000005411 Van der Waals force Methods 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000002074 melt spinning Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 description 1
- 239000002861 polymer material Substances 0.000 description 1
- 238000007873 sieving Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Landscapes
- Polyesters Or Polycarbonates (AREA)
Abstract
The invention discloses a polyarylate based on 1, 2-tetra (4-hydroxyphenyl) ethane and a preparation method thereof, wherein a 4-functional group monomer, 1, 2-tetra (4-hydroxyphenyl) ethane, is introduced into the molecular structure of the polyarylate, so that micro-crosslinking is generated among molecular chains, and the melt strength of resin is improved. The preparation method comprises the following steps: 1. adding p-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, hydroquinone, 1, 2-tetra (4-hydroxyphenyl) ethane, terephthalic acid and acetic anhydride into a polymerization kettle, and preparing a prepolymer of thermotropic liquid crystal polyarylate through melt polycondensation; 2. placing the prepolymer in a rotary kiln under the protection of nitrogen to perform solid-phase polycondensation reaction to obtain high molecular weight polymer powder; the polyarylate resin prepared by the method has a micro-crosslinking structure, high melt strength, difficult fracture during spinning, higher stretching ratio, lower fiber fineness and high mechanical strength.
Description
Technical Field
The invention relates to a preparation method of wholly aromatic polyester, and belongs to the technical field of high polymer materials.
Background
Wholly aromatic polyester is a high-performance polyester material, and is generally known for its high strength, high modulus, excellent melt processing molding characteristics, inherent flame retardancy, low water absorption, chemical resistance and good irradiation resistance, and many uses at high temperatures.
All the wholly aromatic polyester is a benzene ring structure difunctional monomer, the molecular structure is a rigid chain segment, the molecular chain is in an extending state, can not be folded, has little chain entanglement among molecules and only has weak van der Waals force, so that the wholly aromatic polyester has anisotropic liquid crystal state during melt processing, the melt strength is rapidly reduced, cracking is easy to occur, the requirement on processing equipment technology is high, and the product has anisotropic defects.
The patent CN106757476B introduces monomer with double bond in the side chain, and forms microstructure in the structure by photopolymerization method in the later stage of polymerization, thereby improving the melt strength. However, the polyarylate has high polymerization temperature, requires high heat resistance of double bond monomers, requires a photopolymerization step in the subsequent step, and increases the difficulty of resin preparation.
Disclosure of Invention
The invention aims to provide wholly aromatic polyester. Furthermore, it is an object to conveniently prepare polyarylate fibers using such materials. The wholly aromatic polyester fiber has the advantages of excellent performance, low melt strength, difficult control of spinning technology, difficult thinning of the fiber and the like.
The aim of the invention can be achieved by the following technical scheme:
a wholly aromatic polyester comprises p-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, hydroquinone, terephthalic acid, and 1, 2-tetra (4-hydroxyphenyl) ethane as polymerization monomers.
The content of parahydroxybenzoic acid is usually 30 mole% or more, preferably 35 to 55 mole%, more preferably 40 to 55 mole%. The content of 6-hydroxy-2-naphthoic acid is usually 20 mol% or more, preferably 20 to 30 mol%. The content of hydroquinone is generally less than 25 mol%, preferably 8 to 25 mol%. The content of terephthalic acid is usually 25 mol% or less, preferably 8 to 25 mol%.
The ratio of the hydroxyl content of hydroquinone to 1, 2-tetrakis (4-hydroxyphenyl) ethane to the carboxyl content of terephthalic acid is generally from 0.9/1 to 1/0.9, preferably the same.
The content of 1, 2-tetrakis (4-hydroxyphenyl) ethane is 0.2 to 2 mol%.
The preparation method of the wholly aromatic polyester comprises the following steps: putting p-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, hydroquinone, 1, 2-tetra (4-hydroxyphenyl) ethane, terephthalic acid and acetic anhydride into a reaction kettle, heating to react, applying vacuum to continue the reaction after the polycondensation reaction reaches a preset degree, and immediately introducing nitrogen after the polycondensation reaction reaches a required degree to terminate the polymerization reaction. Discharging the materials from the kettle, crushing and drying to obtain the prepolymer. Then placing the prepolymer under the protection of nitrogen, and carrying out solid-phase polycondensation reaction in a nitrogen oven at 220-280 ℃ to obtain high molecular weight polyester powder;
the above-described high melt strength wholly aromatic polyester is capable of melt processing at a temperature of about 260 to 320 ℃.
The above-described high melt strength wholly aromatic polyester exhibits an inherent viscosity of 5.5 to 8.0 when dissolved in pentafluorophenol at a concentration of 0.025 wt% at 60 ℃.
In the molecular design of the invention, a small amount of 4-functional group monomer, 1, 2-tetra (4-hydroxyphenyl) ethane is introduced, and a cross-linking point is formed between molecular chains by direct reaction in polymerization, so that a strong intermolecular force micro-crosslinking structure is generated, and the fiber has high melt strength, good spinning processability, low fineness of the prepared fiber and high mechanical strength, as shown in figure 1.
The wholly aromatic polyester with high melt strength obtained according to the present invention may be produced into wholly aromatic polyester fibers by a known melt spinning method. In the spinning process, the fiber is not easy to break, can bear higher stretching ratio, and has lower prepared fiber fineness and high mechanical strength.
Drawings
FIG. 1 is a schematic diagram of the structure of the cross-linking points formed between molecular chains according to the present invention.
Detailed Description
The wholly aromatic polyester resin of the invention is composed of main repeating units of p-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, terephthalic acid and hydroquinone, and also contains a small amount of 1, 2-tetra (4-hydroxyphenyl) ethane repeating units.
The present invention will be further illustrated by the following examples and comparative examples, without departing from the spirit of the invention, which should not be limited to what is specifically illustrated by the following examples.
The product performance testing method comprises the following steps:
the present invention uses a differential scanning calorimeter (DSC 8000, perkinelmer, U.S.A.) to test the melting point (T) m ) The test was performed according to ASTM D3418 method. The invention uses an Ubbelohde viscometer (IV 6400H full-automatic ultra-high temperature viscometer, hangzhou Zhuo Xiang) to test the inherent viscosity; specifically, the liquid crystal polyester was dissolved in pentafluorophenol at a concentration of 0.025 wt% at 60℃and tested with reference to the GB/T1632.1 method. The fineness of the fibers was measured according to GB/T14343-2008. The mechanical properties of the fibres were measured according to GB/T19975-2005.
Example 1:
firstly, p-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, hydroquinone, 1, 2-tetra (4-hydroxyphenyl) ethane react with acetic anhydride at the constant temperature of 120-130 ℃ for 1 hour, then rise to 185-195 ℃ in 2 hours, react at the constant temperature for 0.5-1 hour, continue to raise the temperature for melt polycondensation, and start to apply vacuum for continuous reaction after reaching the preset degree; immediately after the reaction reaches the required degree, nitrogen is introduced to terminate the polymerization reaction, and the mixture is reactedDischarging the materials from the kettle, crushing, sieving with a 20-mesh sieve, and drying at 140 ℃ for 2 hours to obtain the prepolymer. Placed under a nitrogen flow of 0.3m 3 And (3) under the protection of/h, carrying out solid-phase polycondensation reaction for 8h in a nitrogen oven at 245 ℃ to obtain high molecular weight polymer powder. The melting point and inherent viscosity of the wholly aromatic polyester obtained were measured. The monomer ratio for preparing the wholly aromatic polyester 1 is as follows: 40 mol% of p-hydroxybenzoic acid, 26 mol% of 6-hydroxy-2-naphthoic acid, 15 mol% of hydroquinone, 17 mol% of terephthalic acid and 1 mol% of 1, 2-tetra (4-hydroxyphenyl) ethane. The melting point of the wholly aromatic polyester thus obtained was 262℃and the inherent viscosity was 6.7.
Example 2:
the polyester synthesized in this example was prepared in the same manner as in example 1, and the solid phase polycondensation was carried out at a temperature of 250℃for 8 hours. The monomer ratio for preparing the wholly aromatic polyester 2 is as follows: 40 mol% of p-hydroxybenzoic acid, 26 mol% of 6-hydroxy-2-naphthoic acid, 16 mol% of hydroquinone, 17 mol% of terephthalic acid and 0.5 mol% of 1, 2-tetra (4-hydroxyphenyl) ethane. The melting point of the prepared wholly aromatic polyester was 265℃and the inherent viscosity was 6.3.
Example 3:
the polyester synthesized in this example was prepared in the same manner as in example 1, and the solid phase polycondensation was carried out at a temperature of 270℃for 8 hours. The monomer ratio for preparing the wholly aromatic polyester 3 is as follows: 48 mol% of p-hydroxybenzoic acid, 22 mol% of 6-hydroxy-2-naphthoic acid, 12 mol% of hydroquinone, 15 mol% of terephthalic acid and 1.5 mol% of 1, 2-tetra (4-hydroxyphenyl) ethane. The melting point of the wholly aromatic polyester 4 thus obtained was 282℃and the inherent viscosity was 6.4.
Example 4:
the polyester synthesized in this example was prepared in the same manner as in example 1, and the solid phase polycondensation was carried out at a temperature of 285℃for 12 hours. The monomer ratio for preparing the wholly aromatic polyester 4 is as follows: 50 mol% of p-hydroxybenzoic acid, 18 mol% of 6-hydroxy-2-naphthoic acid, 12 mol% of hydroquinone, 16 mol% of terephthalic acid and 2 mol% of 1, 2-tetra (4-hydroxyphenyl) ethane. The melting point of the wholly aromatic polyester 4 thus obtained was 302℃and the inherent viscosity was 6.7.
Comparative example 1:
the polyester synthesized in comparative example 1 was prepared in the same manner as in example 1, and the solid phase polycondensation was carried out at a temperature of 260℃for a period of 8 hours. The monomer ratio for preparing the wholly aromatic polyester is as follows: 48 mol% of p-hydroxybenzoic acid, 22 mol% of 6-hydroxy-2-naphthoic acid, 15 mol% of hydroquinone and 15 mol% of terephthalic acid. The melting point of the wholly aromatic polyester obtained was 286℃and the inherent viscosity was 6.2.
Comparative example 2:
the polyester synthesized in comparative example 2 was prepared in the same manner as in example 1, under the solid phase polycondensation condition of 250℃for 8 hours. The monomer ratios for preparing the wholly aromatic polyester 10 are as follows: 48 mol% of p-hydroxybenzoic acid, 22 mol% of 6-hydroxy-2-naphthoic acid, 10 mol% of hydroquinone, 15 mol% of terephthalic acid and 2.5 mol% of 1, 2-tetra (4-hydroxyphenyl) ethane. The melting point of the wholly aromatic polyester obtained was 276℃and the inherent viscosity was 3.3.
Comparative example 3:
the polyester synthesized in comparative example 3 was prepared in the same manner as in example 1, and the solid phase polycondensation was carried out at a temperature of 245℃for a period of 8 hours. The monomer ratios for preparing the wholly aromatic polyester 10 are as follows: 48 mol% of p-hydroxybenzoic acid, 22 mol% of 6-hydroxy-2-naphthoic acid, 8 mol% of hydroquinone, 15 mol% of terephthalic acid and 3.5 mol% of 1, 2-tetra (4-hydroxyphenyl) ethane. The melting point of the wholly aromatic polyester obtained was 268℃and the inherent viscosity was 2.3.
The wholly aromatic polyester resin compositions prepared in the above examples 1 to 4 and comparative examples 1 to 3 were spun into wholly aromatic polyester fibers by known spinning, and the spinning speed was gradually increased until the filament bundles began to frequently break. Parameters were recorded that allowed stable winding of the finest fibers, and the processability and properties of the corresponding prepared fibers are shown in table 1.
TABLE 1 fully aromatic polyester spinning processability and fiber Properties thereof
As can be seen from comparative examples 1-4 and comparative example 1, the fibers prepared from the resin without 1, 2-tetrakis (4-hydroxyphenyl) ethane have a low melt strength and can only be prepared as fibers having a minimum diameter of 25. Mu.m. And the resin added with 1, 2-tetra (4-hydroxyphenyl) ethane can prepare the fiber with the minimum diameter of 18 mu m, and the fiber strength is higher. In comparative examples 2 to 3, the addition amount of 1, 2-tetrakis (4-hydroxyphenyl) ethane was excessive, and the molecular weight of the synthesized resin was low, and thus the fiber could not be stably produced.
Claims (8)
1. A polyarylate based on 1, 2-tetrakis (4-hydroxyphenyl) ethane, characterized in that: the polymerized monomers are composed of p-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, hydroquinone, terephthalic acid and 1, 2-tetra (4-hydroxyphenyl) ethane; wherein,
the content of the p-hydroxybenzoic acid is more than 30 mole percent; the content of 6-hydroxy-2-naphthoic acid is usually 20 mol% or more; the hydroquinone content is generally below 25 mole%; the content of terephthalic acid is usually 25 mol% or less.
2. A polyarylate based on 1, 2-tetrakis (4-hydroxyphenyl) ethane according to claim 1, wherein: the content of the p-hydroxybenzoic acid is 35-55 mol%; the content of 6-hydroxy-2-naphthoic acid is usually 20 to 30 mol%; the hydroquinone content is generally from 8 to 25 mol%; the terephthalic acid content is generally 8 to 25 mole%.
3. A polyarylate based on 1, 2-tetrakis (4-hydroxyphenyl) ethane according to claim 1, wherein: the ratio of the hydroxyl content of hydroquinone to 1, 2-tetra (4-hydroxyphenyl) ethane to the carboxyl content of terephthalic acid is 0.9/1-1/0.9.
4. A polyarylate based on 1, 2-tetrakis (4-hydroxyphenyl) ethane according to claim 3, wherein: the ratio of the hydroxyl content of hydroquinone to 1, 2-tetrakis (4-hydroxyphenyl) ethane to the carboxyl content of terephthalic acid is the same.
5. A polyarylate based on 1, 2-tetrakis (4-hydroxyphenyl) ethane according to claim 1, wherein: the content of 1, 2-tetrakis (4-hydroxyphenyl) ethane is 0.2 to 2 mol%.
6. A process for the preparation of a polyarylate based on 1, 2-tetrakis (4-hydroxyphenyl) ethane according to any of claims 1 to 5, characterized in that: the method comprises the following steps: putting p-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, hydroquinone, 1, 2-tetra (4-hydroxyphenyl) ethane, terephthalic acid and acetic anhydride into a reaction kettle, heating to react, applying vacuum to continue the reaction after the polycondensation reaction reaches a preset degree, and immediately introducing nitrogen after the polycondensation reaction reaches a required degree to terminate the polymerization reaction; discharging the materials from the kettle, and crushing and drying to obtain prepolymer; and then placing the prepolymer under the protection of nitrogen, and carrying out solid-phase polycondensation reaction in a nitrogen oven at 220-280 ℃ to obtain the high molecular weight polyester powder.
7. The method for producing a polyarylate based on 1, 2-tetrakis (4-hydroxyphenyl) ethane according to claim 6, wherein: the prepared polyarylate is melt-processed at a temperature of 260 to 320 ℃.
8. Polyarylate based on 1, 2-tetrakis (4-hydroxyphenyl) ethane according to any of claims 1 to 5, characterized by: when dissolved in pentafluorophenol at a concentration of 0.025 wt.% at 60 ℃, it exhibits an inherent viscosity of 5.5 to 8.0.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311802066.8A CN117887049A (en) | 2023-12-26 | 2023-12-26 | Polyarylate based on 1, 2-tetra (4-hydroxyphenyl) ethane and preparation method thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311802066.8A CN117887049A (en) | 2023-12-26 | 2023-12-26 | Polyarylate based on 1, 2-tetra (4-hydroxyphenyl) ethane and preparation method thereof |
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| CN117887049A true CN117887049A (en) | 2024-04-16 |
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| CN202311802066.8A Pending CN117887049A (en) | 2023-12-26 | 2023-12-26 | Polyarylate based on 1, 2-tetra (4-hydroxyphenyl) ethane and preparation method thereof |
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