Polyarylester containing furandicarboxylic acid unit and preparation method thereof

Abstract

The invention relates to polyarylester containing a furandicarboxylic acid unit and a preparation method thereof, and the polyarylester is prepared by the following steps: carrying out melt polycondensation on several monomers such as p-hydroxybenzoic acid, biphenol, terephthalic acid, 2, 5-furandicarboxylic acid and acetaminophen to prepare a prepolymer; and carrying out solid-phase polycondensation reaction on the prepolymer in a rotary kiln under a nitrogen protection condition. The furan-dicarboxylic acid is used as a bio-based product, is a green and renewable substitute of terephthalic acid / isophthalic acid, and meets the green and environment-friendly requirements in the future. The polyarylester obtained by the method can be subjected to melt processing at the temperature of 330-390 DEG C, and is engineering plastic with excellent mechanical properties.

Description

Technical Field

[0001] The present invention relates to the preparation of a fully aromatic polyester and a preparation method thereof, in particular to a high molecular weight polyarylate having excellent fluidity and mechanical properties and being used as engineering plastics and a preparation method thereof, belonging to the technical field of polymer materials. Background Art

[0002] Wholly aromatic polyester is a high-performance polyester material, generally known for its high strength, high modulus, excellent melt processing properties, inherent flame retardancy, low water absorption, chemical resistance and good radiation resistance, as well as many uses at high temperatures.

[0003] The polymerization monomers used in traditional fully aromatic polyesters are all benzene ring structure bifunctional monomers, which come from the petrochemical industry and are non-renewable resources. They do not meet the requirements of future green environmental protection. From the perspective of environmental protection, the use of monomers from biomass resources to produce polyarylates is more in line with future industrial trends. As a monomer derived from biomass, furan dicarboxylic acid can be used as a green and renewable alternative to terephthalic acid / isophthalic acid, which is of great significance. There is still little research in the industry on the use of furan dicarboxylic acid as a monomer to produce polyarylates.

[0004] Patent CN106519200 discloses a method for preparing liquid crystal polymers using 2,5-furan-dicarboxylic acid, terephthalic acid, resorcinol and acetic anhydride. The resin prepared by this method has a melting temperature range of 160-320°C and is mainly used as a general plastic flowability improver and in-situ reinforcement material.

[0005] The polyarylate prepared by using furandicarboxylic acid has a melting temperature range of 330-390° C., has excellent flowability and mechanical properties, and can be used alone as engineering plastics. Summary of the invention

[0006] The purpose of the present invention is to provide a polyarylate containing furandicarboxylic acid units and a preparation method thereof; it relates to the preparation of a wholly aromatic polyester and a preparation method thereof, in particular to a high molecular weight polyarylate having excellent flowability and mechanical properties and being used as an engineering plastic and a preparation method thereof.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] A polyarylate containing furandicarboxylic acid units is prepared by polymerizing monomers of p-hydroxybenzoic acid, biphenol, terephthalic acid, furandicarboxylic acid and acetaminophen; wherein the content of p-hydroxybenzoic acid is 55-70 mol%, the amount of biphenol is 9-21 mol%, the amount of terephthalic acid is 6-16 mol%, the amount of 2,5-furandicarboxylic acid is 5-10 mol%; and the amount of acetaminophen is 1-7 mol%. The molecular formula of furandicarboxylic acid is as follows:

[0009]

[0010] The sum of the moles of biphenol and acetaminophen is A; the sum of the moles of terephthalic acid and FDCA is B, and the ratio of A / B is 0.9 / 1 to 1 / 0.9.

[0011] The preparation method of polyarylate containing furandicarboxylic acid unit is as follows: first, p-hydroxybenzoic acid, biphenol, terephthalic acid, furandicarboxylic acid, acetaminophen monomer and acetic anhydride are put into a kettle together and heated to carry out melt polycondensation reaction. After the polycondensation reaction reaches a predetermined degree, vacuum is applied to continue the reaction. After reaching the required degree, nitrogen is immediately introduced to terminate the polymerization reaction, and the material is discharged from the kettle, crushed and dried to obtain a prepolymer. Then, the prepolymer is placed under nitrogen protection conditions and subjected to solid phase polycondensation reaction at 260-300° C. in a nitrogen oven to obtain a high molecular weight polyarylate powder.

[0012] The high melt strength wholly aromatic polyester is melt processed at a temperature of about 330°C to 390°C.

[0013] The above-mentioned wholly aromatic polyester with high melt strength exhibits an inherent viscosity of 4.0 to 7.0 when dissolved in pentafluorophenol at a concentration of 0.025 wt % at 60°C.

[0014] The wholly aromatic polyester obtained according to the present invention has excellent flowability and mechanical properties and can be used as engineering plastics. DETAILED DESCRIPTION

[0015] The fully aromatic polyester of the present invention is composed of p-hydroxybenzoic acid, biphenol, terephthalic acid, furandicarboxylic acid and acetaminophen.

[0016] The present invention is further described below by way of examples. Without violating the spirit of the present invention, the present invention should not be limited to the contents specifically shown in the following examples.

[0017] Embodiment 1:

[0018] First, hydroxybenzoic acid (HBA), biphenol (BP), terephthalic acid (PTA), furandicarboxylic acid (FDCA) and acetaminophen (APAP) are reacted with acetic anhydride at 120-130°C for 1 hour, then the temperature is raised to 185-195°C within 2 hours, and the temperature is kept constant for 0.5-1 hour, and the temperature is continued to be raised for melt polycondensation reaction. After reaching the predetermined degree, vacuum is applied to continue the reaction; nitrogen is immediately introduced after the reaction reaches the desired degree to terminate the polymerization reaction, and the material is discharged from the kettle, crushed, passed through a 20-mesh sieve, and dried at 140°C for 2 hours to obtain a prepolymer. Place the mixture at a nitrogen flow rate of 0.3m 3 Under the protection condition of 100 % NH 2 / h, the solid phase polycondensation reaction was carried out in a nitrogen oven at 265° C. for 4 h to obtain a high molecular weight polymer powder. The melting point, DTUL, and inherent viscosity of the obtained wholly aromatic polyester were measured.

[0019] Embodiment 2:

[0020] The monomer ratio was changed and polyester was prepared in the same manner as in Example 1. The solid phase polycondensation conditions were a temperature of 270 degrees and a time of 4 hours.

[0021] Embodiment 3:

[0022] The monomer ratio was changed and polyester was prepared in the same manner as in Example 1. The solid phase polycondensation conditions were a temperature of 275 degrees and a time of 4 hours.

[0023] The polyarylates obtained in Examples 1-3 above were tested according to the following method. The results are shown in Table 1.

[0024] Product performance test method:

[0025] [Melting point]

[0026] Using a differential scanning calorimeter (DSC 8000, PerkinElmer, USA), the endothermic peak temperature (Tml) observed when the polymer was measured under the condition of a temperature increase of 20°C / min from room temperature was observed, and then the temperature was maintained at (Tml+40)°C for 2 minutes, and then temporarily cooled to room temperature under the condition of a temperature decrease of 20°C / min, and then the temperature of the endothermic peak observed when the polymer was measured again under the condition of a temperature increase of 20°C / min was measured.

[0027] [Mechanical properties and DTUL]

[0028] Using a twin-screw extruder, 70% by mass of the polymer and 30% by mass of glass fiber (Jiushi Glass Fiber, Brand 584) were melt-kneaded at a barrel temperature of the melting point of the polymer + 20°C to obtain polyester resin composition pellets.

[0029] The polyester resin composition pellets were molded using an injection molding machine ("NEX 110T" manufactured by Nissei Plastic Industry Co., Ltd.) under the following molding conditions, and the mechanical properties and deflection temperature under load (bending stress 1.8 MPa) were measured according to the method of GBT1040.2-2006.

[0030] [Molding conditions]

[0031] Barrel temperature: melting point of polymer + 20°C

[0032] Mold temperature: 120℃

[0033] Back pressure: 2MPa

[0034] Injection speed: 110 mm / s

[0035] [Inherent viscosity]

[0036] The present invention uses an Ubbelohde viscometer (IV6400H fully automatic ultra-high temperature viscometer, Hangzhou Zhuoxiang) to test the inherent viscosity; specifically, the liquid crystal polyester is dissolved in pentafluorophenol at a concentration of 0.025 wt % at 60° C., and the test is performed according to the GB / T1632.1 method.

[0037] Table 1: Dosages and test data of Examples 1-3.

[0038]

[0039]

[0040] It can be seen from the results in Table 1 that the polyarylate obtained by the method has a high logarithmic specific viscosity and can be melt-processed at a temperature of 330° C. to 390° C. It is an engineering plastic with excellent mechanical properties and high heat resistance.

Claims

1. A polyarylate containing furandicarboxylic acid units, characterized in that: The invention is prepared by polymerizing several monomers including p-hydroxybenzoic acid, biphenol, terephthalic acid, 2,5-furandicarboxylic acid and acetaminophen; wherein the content of p-hydroxybenzoic acid is 55-70 mol%, the amount of biphenol is 9-21 mol%, the amount of terephthalic acid is 6-16 mol%, the amount of 2,5-furandicarboxylic acid is 5-10 mol%; and the amount of acetaminophen is 1-7 mol%.

2. A polyarylate containing furandicarboxylic acid units according to claim 1, characterized in that: The sum of the moles of biphenol and acetaminophen is A; the sum of the moles of terephthalic acid and furandicarboxylic acid is B, and the ratio of A / B is 0.9 / 1-1 / 0.

9.

3. The method for preparing the polyarylate containing furandicarboxylic acid units according to any one of claims 1 or 2, characterized in that: The steps are as follows: first, para-hydroxybenzoic acid, biphenol, terephthalic acid, furandicarboxylic acid, acetaminophen monomer and acetic anhydride are put into a kettle together and heated to carry out melt polycondensation reaction; after the polycondensation reaction reaches a predetermined degree, vacuum is applied to continue the reaction; after reaching the required degree, nitrogen is immediately introduced to terminate the polymerization reaction; the material is discharged from the kettle, crushed and dried to obtain a prepolymer; Then, the prepolymer is placed under nitrogen protection conditions and subjected to solid phase polycondensation reaction at 260-300° C. in a nitrogen oven to obtain high molecular weight polyarylate powder.

4. The method for preparing a polyarylate containing furandicarboxylic acid units according to claim 3, characterized in that: High molecular weight polyarylate powders can be melt processed at temperatures between 330°C and 390°C.

5. The method for preparing the polyarylate containing furandicarboxylic acid units according to claim 3, characterized in that: When dissolved in pentafluorophenol at a concentration of 0.025 wt % at 60° C., the high molecular weight polyarylate powder exhibits an inherent viscosity of 4.0 to 7.0.

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