A method for preparing high-fluidity polyarylate

Abstract

The present invention provides a method for preparing a high-fluidity polyarylate, the method comprising the following steps: S1: catalytic reaction of fluoroaniline and bisphenol A epoxy resin in solvent A to generate fluorine-containing polyol; S2: bisphenol A, terephthaloyl chloride and isophthaloyl chloride react in solvent B to generate acyl chloride-terminated polyarylate; S3: fluorine-containing polyol and acyl chloride-terminated polyarylate react in solvent C to obtain fluorine-containing branched polyarylate. The present invention synthesizes fluorine-containing polyols with different functionalities, which react with acyl chloride-terminated prepolymers to obtain fluorine-containing polyarylates with different branching degrees. The processing fluidity and solubility of the polyarylate can be improved by controlling the branching degree, and the introduction of fluorine can improve the heat resistance and transparency of the material, greatly improving the performance of the material.

Description

Technical Field

[0001] The invention belongs to the field of polymer materials, and in particular relates to a method for preparing high-fluidity polyarylate. Background Art

[0002] Polyarylate is a high-performance engineering plastic. In industry, it mainly refers to copolymer resins made by polycondensation using bisphenol A, terephthaloyl chloride and isophthaloyl chloride as raw materials. The para- and meta-benzene ring structures in the main chain destroy the regularity of the molecular chain, making the material amorphous and giving polyarylate high transparency; and the high-density combination of aromatic rings and ester groups in the main chain gives the material good heat resistance and mechanical properties. Polyarylate has excellent comprehensive properties and is currently widely used in aerospace, electronics, automotive manufacturing and other fields.

[0003] A large number of benzene rings and ester groups in the main chain of polyarylate give the material excellent heat resistance and mechanical properties. At the same time, this rigid structure increases the material processing temperature and deteriorates the melt fluidity. With the development of the resin industry, the requirements for large-scale, thin, refined and complex shapes of materials are getting higher and higher, and the processing fluidity of polyarylate has become an important factor limiting its application. At present, the means of modification are usually used to improve the processing fluidity of the material, which is divided into physical modification and chemical modification. The main method of physical modification is blending, that is, mixing polyarylate with a small molecule plasticizer or a polymer modifier to reduce the intermolecular force, thereby achieving the purpose of improving processability. Patent CN107075238A improves the processing fluidity of polyarylate by blending polyarylate with aliphatic polyester. Although this method can improve the processing fluidity of the material to a certain extent, the addition of aliphatic polyester will inevitably reduce the heat resistance, mechanical properties, chemical resistance, etc. of the material, limiting the application range of the material.

[0004] In summary, in order to improve processing performance, the art needs polyarylates with better processing fluidity. Summary of the invention

[0005] The object of the present invention is to provide a method for preparing high-fluidity polyarylate, which can improve the processing fluidity of the polyarylate and simultaneously improve the heat resistance and transparency of the material.

[0006] In order to achieve the above invention object, the technical solution adopted by the present invention is as follows:

[0007] A method for preparing a high-fluidity polyarylate, the method comprising the following steps:

[0008] S1: Fluoroaniline and bisphenol A epoxy resin are catalytically reacted in solvent A to generate fluorinated polyols;

[0009] S2: Bisphenol A, terephthaloyl chloride and isophthaloyl chloride react in solvent B to form acyl chloride-terminated polyarylate;

[0010] S3: The fluorinated polyol and the acyl chloride-terminated polyarylate are reacted in solvent C to obtain the fluorinated branched polyarylate.

[0011] The synthesis method of the present invention obtains fluorinated polyols with different functionalities, which can react with acyl chloride-terminated prepolymers to obtain fluorinated polyarylates with different branching degrees. The processing fluidity of polyarylates can be improved by controlling the branching degree, and the introduction of fluorine can improve the heat resistance and transparency of the material, greatly improving the performance of the material.

[0012] In the present invention, the fluoroaniline described in S1 has the following structure:

[0013]

[0014] Among them, at least one of R1 to R5 is a fluorine substituent.

[0015] In the present invention, the bisphenol A epoxy resin described in S1 has the following structure:

[0016]

[0017] Wherein, n is an integer, 1≤n≤5; preferably, the molar ratio of fluoroaniline to bisphenol A epoxy resin in S1 is 2:1.

[0018] In the present invention, the solvent A described in S1 is an aprotic polar solvent, preferably one or more of N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, cyclopentane, diphenyl sulfone, chloroform, dichloroethane, tetrahydrofuran and 1,4-dioxane.

[0019] In the present invention, the catalyst in S1 is 1,5,7-triazabicyclo[4,4,0]dec-5-ene; preferably, the molar ratio of the catalyst to fluoroaniline is 0.5:1 to 1:1.

[0020] In the present invention, the reaction temperature of S1 is 100-130°C, and the reaction time is 10-20h.

[0021] In the present invention, the molar ratio of bisphenol A, terephthaloyl chloride and isophthaloyl chloride in S2 is 9:5:5 to 9.8:5:5.

[0022] In the present invention, the solvent B described in S2 is an inert high boiling point solvent, preferably o-dichlorobenzene and / or nitrobenzene.

[0023] In the present invention, the reaction temperature of S2 is 180-210°C, and the reaction time is 10-20h.

[0024] In the present invention, the molar ratio of the fluorinated polyol in S3 to the acyl chloride-terminated polyarylate is 1:1 to 1:5, preferably 1:2 to 1:3, calculated based on the molar number of hydroxyl groups.

[0025] In the present invention, the solvent C described in S3 is an aprotic polar solvent, preferably one or more of N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, cyclopentane, diphenyl sulfone, chloroform, dichloroethane, tetrahydrofuran and 1,4-dioxane.

[0026] In the present invention, the reaction temperature of S3 is 140-190° C., and the reaction time is 5-10 h.

[0027] In one embodiment, the corresponding polyarylate product is obtained using the following raw materials:

[0028] S1 prepared the following fluorinated polyols:

[0029]

[0030] When n=1, the fluorinated polyol is:

[0031]

[0032] The acyl chloride-terminated polyarylate product obtained in S2 is as follows:

[0033]

[0034] The two react in S3 to obtain the following product:

[0035]

[0036] Another object of the present invention is to provide a high-fluidity polyarylate.

[0037] A high-fluidity polyarylate is prepared by the preparation method, wherein the polyarylate has a viscosity [η] of 0.58-0.94 dL / g and a melt flow rate of 4.24-6.27 g / 10 min at 280° C. and 2.16 kg.

[0038] Compared with the prior art, the positive effects of the present invention are:

[0039] (1) The processing fluidity of polyarylate was improved, and the melt index increased from 3.78 g / 10 min to 6.27 g / 10 min.

[0040] (2) The heat resistance and transparency of the material are improved, and the glass transition temperature increases from 219°C to 230°C, which greatly broadens the application range of the material. DETAILED DESCRIPTION

[0041] According to the above-mentioned preparation method of high-fluidity polyarylate, the following examples are given, which are not intended to limit the protection scope of the present invention.

[0042] Chemical raw material information

[0043] name Specification factory N,N-Dimethylformamide AR Aladdin 4-Fluoroaniline 99％ Aladdin Bisphenol A epoxy resin 98％ Shanghai Kaiyin Chemical 1,5,7-Triazabicyclo[4,4,0]dec-5-ene ≥98％ Zhuhai Bairui Pharmaceuticals Bisphenol A ＞99％ Aladdin Terephthaloyl chloride 99％ Aladdin Isophthaloyl chloride 99％ Aladdin o-Dichlorobenzene 99％ Aladdin N-Methylpyrrolidone AR Aladdin N,N-Dimethylacetamide AR Aladdin 2,4-Difluoroaniline 99％ Aladdin Nitrobenzene AR Shanghai Baishun Biotechnology 2,3,4,5,6-Pentafluoroaniline 98％ Hubei Chengfeng Chemical 2,3,4-Trifluoroaniline 99％ Aladdin

[0044] Main characterization methods:

[0045] A. Intrinsic viscosity test: using Ubbelohde viscometer, 0.25g / L N-methylpyrrolidone solution.

[0046] B. Melt index test: Use Zhongtian Instrument ZT-5605 melt index tester, temperature 280℃, load 2.16kg.

[0047] C. Glass transition temperature test: using METTLER DSC-1 differential scanning calorimeter, heating rate 10°C / min.

[0048] D. NMR carbon spectrum test: A Bruker Avance-400 MHz NMR instrument was used, deuterated chloroform was used as solvent, and TMS was used as internal standard.

[0049] Example 1

[0050] In a three-necked flask with mechanical stirring, 100 mL of N,N-dimethylformamide, 0.2 mol of 4-fluoroaniline, 0.1 mol of bisphenol A epoxy resin (molecular weight 624.82) and 0.1 mol of 1,5,7-triazabicyclo[4,4,0]dec-5-ene were added in sequence. Under nitrogen protection, the temperature was raised to 100°C and the reaction was carried out for 20 hours to generate a fluorinated triol.

[0051] In a three-necked flask equipped with a mechanical stirrer, a condenser and a nitrogen inlet and outlet, 0.45 mol of bisphenol A, 0.25 mol of terephthaloyl chloride, 0.25 mol of isophthaloyl chloride and 500 mL of o-dichlorobenzene were added in sequence, and the mixture was reacted at 180° C. for 20 hours to obtain an acyl chloride-terminated polyarylate.

[0052] 0.1 mol of fluorinated triol, 0.3 mol of polyarylate and 200 mL of N,N-dimethylformamide were added to a three-necked flask equipped with a mechanical stirrer, and the mixture was reacted at 140°C for 10 hours to obtain branched polyarylate. The viscosity was measured by an Ubbelohde viscometer (N-methylpyrrolidone solution) to be [η] = 0.58 dL / g; the melt index was measured to be 4.26 g / 10 min (280°C, 2.16 kg); the glass transition temperature was measured by a differential scanning calorimeter (DSC) to be Tg = 220°C.

[0053] The product characterization results are: 13 C-NMR (CDCl3), δ: 30.9, 42.4, 46.7, 66.7, 66.8, 70, 72, 114.9, 116.3, 118.9, 120.3, 122.1, 128.6, 128.9, 129.3, 130.1, 130 .2,130.5,132.8,133,134.5,135.3,135.4,136.9,146.3,146.8,146.9,151.5,155.7,156.9,159.4,165.2,165.9,167.9.

[0054] Example 2

[0055] In a three-necked flask with stirring and oil bath heating, add 1L N,N-dimethylacetamide, 2 mol 2,4-difluoroaniline, 1 mol bisphenol A epoxy resin (molecular weight 909.19) and 2 mol 1,5,7-triazabicyclo[4,4,0]dec-5-ene, and stir the reaction at 130°C for 10 hours to generate fluorinated tetraol.

[0056] In a stirred reactor capable of passing nitrogen, 4.9 mol of bisphenol A, 2.5 mol of terephthaloyl chloride, 2.5 mol of isophthaloyl chloride and 5 L of nitrobenzene were added in sequence, nitrogen was passed through, and the mixture was stirred and reacted at 210° C. for 10 h to obtain polyarylate terminated with acyl chloride.

[0057] 0.2 mol of fluorinated tetraol, 4 mol of polyarylate and 400 mL of N,N-dimethylacetamide were added to a three-necked flask equipped with a mechanical stirrer, and the mixture was reacted at 160°C for 8 hours to obtain branched polyarylate. The viscosity was measured by an Ubbelohde viscometer (N-methylpyrrolidone solution) to be [η] = 0.66 dL / g; the melt index was measured to be 4.59 g / 10 min (280°C, 2.16 kg); the glass transition temperature was measured by a differential scanning calorimeter (DSC) to be Tg = 223°C.

[0058] Example 3

[0059] In a reaction flask, add 50 mL of N-methylpyrrolidone, 0.1 mol of 2,3,4-trifluoroaniline, 0.05 mol of bisphenol A epoxy resin (molecular weight 1762.3) and 0.08 mol of 1,5,7-triazabicyclo[4,4,0]dec-5-ene while stirring. Under nitrogen protection, raise the temperature to 120°C and react for 15 hours to generate a fluorinated heptahydric alcohol.

[0060] 0.475 mol of bisphenol A, 0.25 mol of terephthaloyl chloride, 0.25 mol of isophthaloyl chloride and 500 mL of nitrobenzene were added in sequence into a reaction device equipped with a mechanical stirrer, and the mixture was reacted at 210° C. for 10 hours to obtain an acyl chloride-terminated polyarylate.

[0061] 0.1 mol of fluorinated heptahydric alcohol, 1.75 mol of polyarylate and 200 mL of N-methylpyrrolidone were added to a three-necked flask equipped with a mechanical stirrer, and the mixture was reacted at 190°C for 5 hours to obtain branched polyarylate. The viscosity was measured by an Ubbelohde viscometer (N-methylpyrrolidone solution) to be [η] = 0.94 dL / g; the melt index was measured to be 6.27 g / 10 min (280°C, 2.16 kg); the glass transition temperature was measured by a differential scanning calorimeter (DSC) to be Tg = 225.6°C.

[0062] Example 4

[0063] 100 mL of N,N-dimethylformamide, 0.2 mol of 2,3,4,5,6-pentafluoroaniline, 0.1 mol of bisphenol A epoxy resin (molecular weight 624.82) and 0.1 mol of 1,5,7-triazabicyclo[4,4,0]dec-5-ene were added to a stirred reaction apparatus, and the temperature was raised to 100° C. under nitrogen protection, and the reaction was carried out for 20 hours to generate a fluorinated triol.

[0064] In a three-necked flask equipped with a mechanical stirrer, a condenser and a nitrogen inlet and outlet, 0.45 mol of bisphenol A, 0.25 mol of terephthaloyl chloride, 0.25 mol of isophthaloyl chloride and 500 mL of o-dichlorobenzene were added in sequence, and the mixture was reacted at 180° C. for 20 hours to obtain an acyl chloride-terminated polyarylate.

[0065] 0.1 mol of fluorinated triol, 0.3 mol of polyarylate and 200 mL of N,N-dimethylformamide were added to a three-necked flask equipped with a mechanical stirrer, and the mixture was reacted at 140°C for 10 hours to obtain branched polyarylate. The viscosity was measured by an Ubbelohde viscometer (N-methylpyrrolidone solution) to be [η] = 0.59 dL / g; the melt index was measured to be 4.24 g / 10 min (280°C, 2.16 kg); the glass transition temperature was measured by a differential scanning calorimeter (DSC) to be Tg = 230°C.

[0066] Comparative Example 1

[0067] Compared with Example 1, the difference is that a multifunctional monomer is used and a traditional polymerization method is adopted to synthesize a linear polyarylate.

[0068] 1.8 mol of bisphenol A, 1 mol of terephthaloyl chloride, 1 mol of isophthaloyl chloride and 2L of o-dichlorobenzene were put into a reactor equipped with temperature control, stirring and reflux devices at one time, and the temperature was controlled at 180°C for 20 hours to obtain polyarylate terminated with acyl chloride. The viscosity was measured by Ubbelohde viscometer (N-methylpyrrolidone solution) as [η] = 0.51 dL / g; the melt index was measured by a melt flow rate of 3.78 g / 10 min (280°C, 2.16 kg); the glass transition temperature Tg was measured by a differential scanning calorimeter (DSC) as 219°C.

[0069] It can be seen from the comparative examples that, compared with the polyarylate prepared by the traditional method, the processing fluidity and heat resistance of the fluorinated branched polyarylate prepared by the present invention are improved, which greatly broadens the application range of the material.

Claims

1. A method for preparing a high-fluidity polyarylate, characterized in that: The method comprises the following steps: S1: Fluoroaniline and bisphenol A epoxy resin are catalytically reacted in solvent A to generate fluorinated polyols; S2: Bisphenol A, terephthaloyl chloride and isophthaloyl chloride react in solvent B to form acyl chloride-terminated polyarylate; S3: The fluorinated polyol and the acyl chloride-terminated polyarylate are reacted in solvent C to obtain the fluorinated branched polyarylate.

2. The preparation method according to claim 1, characterized in that: The fluoroaniline described in S1 has the following structure: wherein at least one of R1 to R5 is a fluorine substituent; And / or, the bisphenol A epoxy resin described in S1 has the following structure: Wherein, n is an integer, 1≤n≤5.

3. The preparation method according to claim 2, characterized in that: The molar ratio of fluoroaniline to bisphenol A epoxy resin in S1 is 2:

1.

4. The preparation method according to claim 1 or 2, characterized in that: S1 The solvent A is an aprotic polar solvent; and / or, the catalyst in S1 is 1,5,7-triazabicyclo[4,4,0]dec-5-ene; And / or, the reaction temperature of S1 is 100-130° C., and the reaction time is 10-20 h.

5. The preparation method according to claim 4, characterized in that: S1 The solvent A is one or more of N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, sulfolane, diphenyl sulfone, chloroform, dichloroethane, tetrahydrofuran and 1,4-dioxane; The molar ratio of the catalyst to fluoroaniline in S1 is 0.5:1 to 1:

1.

6. The preparation method according to claim 1, characterized in that: The molar ratio of bisphenol A, terephthaloyl chloride and isophthaloyl chloride in S2 is 9:5:5 to 9.8:5:5; And / or, the solvent B in S2 is an inert high boiling point solvent; And / or, S2 reaction temperature is 180-210°C, and reaction time is 10-20h.

7. The preparation method according to claim 6, characterized in that: S2 The solvent B is o-dichlorobenzene and / or nitrobenzene.

8. The preparation method according to claim 1, characterized in that: The molar ratio of the fluorinated polyol in S3 to the acyl chloride-terminated polyarylate is 1:1 to 1:5, calculated based on the molar number of hydroxyl groups; and / or, the solvent C in S3 is an aprotic polar solvent; And / or, the reaction temperature of S3 is 140-190° C., and the reaction time is 5-10 h.

9. The preparation method according to claim 8, characterized in that: The molar ratio of the fluorinated polyol in S3 to the acyl chloride-terminated polyarylate is 1:2 to 1:3, calculated based on the molar number of hydroxyl groups; And / or, the solvent C in S3 is one or more of N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, cyclopentane, diphenyl sulfone, chloroform, dichloroethane, tetrahydrofuran and 1,4-dioxane.

10. A high-fluidity polyarylate prepared by the preparation method according to any one of claims 1 to 9, wherein the polyarylate has a viscosity [η] of 0.58 to 0.94 dL / g and a melt flow rate of 4.24 to 6.27 g / 10 min at 280°C and 2.16 kg.

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