Frangicarboxylic acid-based polyamide resin, method for producing the same, and composition for polyamide molding

Abstract

The present invention discloses a furandicarboxylic acid-based polyamide resin. The furandicarboxylic acid-based polyamide resin is derived from repeating units containing (A) 2,5-furandicarboxylic acid, (B) 1,4-cyclohexanedicarboxylic acid, and (C) 1,10-decanediamine, and (A) accounts for 5 to 45 mol% of the diacid units in terms of the total mol% of the diacid units. The use of bio-based 2,5-furandicarboxylic acid, which has the advantages of a melting point of 290 to 336°C, low water absorption (lower water absorption rate than polyamides with the same amide bond density), and excellent dimensional stability, improves environmental protection. On the other hand, cyclohexane has a higher rigidity than aromatic rings and can form more hard carbon layers when burned. Furthermore, furandicarboxylic acid-based polyamides have a high amide bond density and can achieve excellent synergistic effects when used in combination with flame retardants, and the synergistic effects of the two provide excellent flame retardant effects.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and particularly relates to a phthalic acid-based polyamide resin, a method for producing the same, and a polyamide molding composition.

Background Art

[0002] Conventional polyamide monomers are mainly derived from petroleum, and currently face problems such as excessive consumption of petroleum resources, a sharp increase in carbon dioxide emissions, and the intensification of the greenhouse effect. Reducing the use of petroleum-based monomers can suppress carbon dioxide emissions, prevent the greenhouse effect, solve problems of environmental pollution and resource constraints, and build a sustainable society. Bio-based high-temperature resistant polyamides mainly refer to polyamides obtained by polymerization of bio-based aliphatic diamines or bio-based aromatic ring dicarboxylic acids. Bio-based monomers are usually extracted from animals and plants, which can achieve green and sustainable development. On the other hand, it can diversify high-temperature resistant polyamide products and meet the demands of more segmented industries.

[0003] As a result of market research and analysis, decanediamine, pentamethylenediamine, and phthalic acid, which are bio-based monomers, are considered to be the bio-based high-temperature resistant polyamide monomer materials with the highest possibility of achieving substantial progress. Decanediamine is derived from castor oil plants and has already been mass-produced in China, but its selling price is high and its market competitiveness is weak. Pentamethylenediamine is obtained by fermentation of glutamic acid, and large-scale production has been achieved in China. It has a low price and good market competitiveness. Phthalic acid is the only bio-based aromatic ring dicarboxylic acid monomer that is currently known and has the highest possibility of being industrialized in the near future. Currently, research on phthalic acid at home and abroad is in the stage of experimental research and development.

[0004] Chinese patent application CN106536187A discloses a furan-based polyamide using the bio-based monomer 2,5-franzicarboxylic acid, where the diamine is an aliphatic diamine, aromatic diamine, etc., and it has the advantage of good gas barrier properties. However, this gas barrier property is mainly achieved by polymerizing short-carbon chain diamines (1,3-propanediamine) to increase the density of amide bonds. However, this furan polyamide has poor flame retardancy. [Overview of the project] [Problems that the invention aims to solve]

[0005] The objective of the present invention is to provide a flangic acid-based polyamide that has the advantages of excellent flame retardancy, a high melting point, low water absorption, and being bio-based. Another object of the present invention is to provide a composition containing the above-mentioned flanger carboxylic acid-based polyamide. [Means for solving the problem]

[0006] This invention is achieved by the following technical solution.

[0007] The frangic acid-based polyamide resin is derived from repeating units containing (A) 2,5-frangic acid, (B) 1,4-cyclohexanedicarboxylic acid, and (C) 1,10-decanediamine, where (A) accounts for 5 to 45 mol% of the total molar percentage of the diacid units.

[0008] Preferably, in terms of the total mole percent of diacid units, (A) accounts for 5 to 25 mol% of the diacid units.

[0009] More preferably, in terms of the total mole percent of diacid units, (A) accounts for 5 to 15 mol% of the diacid units.

[0010] Preferably, the water absorption rate and shrinkage rate are lower at a content of (A) relative to the diacid unit.

[0011] The relative viscosity of the aforementioned flange carboxylic acid-based polyamide resin is 1.8 to 2.4.

[0012] The melting point of the aforementioned flange carboxylic acid-based polyamide resin is 290 to 336°C.

[0013] The water absorption rate of the aforementioned flange carboxylic acid-based polyamide resin is 1.5% or less.

[0014] The lateral / vertical shrinkage rate of the aforementioned flange carboxylic acid-based polyamide resin is 0.2% / 0.5% or less.

[0015] The reaction raw materials (diamine, diacid) are added in a predetermined ratio to a pressure vessel equipped with a magnetic coupling stirrer, condenser tube, gas phase port, supply port, and pressure-resistant explosion-proof port. Next, benzoic acid, sodium hypophosphite (catalyst), and deionized water are added so that the amount of benzoic acid is 2-3% of the total amount of diamine and diacid, the weight of sodium hypophosphite is 0.05-0.15% of the weight of the other input raw materials other than deionized water, and the weight of deionized water is 25-35% of the total weight of the input raw materials. Vacuum suction is then applied, a protective gas as high-purity nitrogen is introduced, and the mixture is stirred for 2 hours. The reaction mixture is heated to 10-230°C, stirred at 210-230°C for 0.5-2 hours, then the temperature of the reactants is raised to 220-240°C while stirring, and the reaction is sustained at a constant temperature of 220-240°C and a constant pressure of 2.1-2.3 MPa for 1-3 hours. The formed water is removed and the pressure is kept constant. After the reaction is complete, the materials are discharged, the prepolymer is vacuum-dried at 70-90°C to obtain a prepolymerization product, and the prepolymerization product is thickened in solid phase at 240-260°C and under a vacuum of 40-60 Pa for 8-12 hours to obtain a frangic acid-based polyamide resin.

[0016] A polyamide molding composition comprising, The present invention comprises 40 to 70 parts by weight of the above-mentioned flange carboxylic acid-based polyamide resin, 10 to 30 parts by weight of non-halogen flame retardant, Includes 0 to 50 parts by weight of reinforcing material.

[0017] The non-halogen flame retardant is at least one selected from phosphine-based flame retardants, phosphinate-based flame retardants, hypophosphonite-based flame retardants, phosphonite-based flame retardants, phosphonite-based flame retardants, phosphite-based flame retardants, phosphine oxide-based flame retardants, phosphinate-based flame retardants, hypophosphonite-based flame retardants, phosphonate-based flame retardants, phosphonate-based flame retardants, phosphate-based flame retardants, polyphosphate-based flame retardants, or phosphinate-based flame retardants; the hypophosphinate-based flame retardant is at least one selected from aluminum hypophosphite or calcium hypophosphite; the phosphinate-based flame retardant is at least one selected from aluminum dimethylphosphinate, aluminum diethylphosphinate, or aluminum methylethylphosphinate; and the phosphate-based flame retardant is bisphenol A bis(diphenyl phosphate) , Zolcinol (diphenyl phosphate), triphenyl phosphate, or Melanin phosphate Nka The polyphosphate-based flame retardant is at least one selected from the above, and the polyphosphate-based flame retardant is ammonium polyphosphate, melamine polyphosphate, melamine pyrophosphate, or Melamine polyphosphate It is at least one of the following.

[0018] The reinforcing material is at least one selected from fibrous fillers and non-fibrous fillers, the fibrous filler is at least one selected from glass fibers, carbon fibers, basalt fibers, bamboo fibers, hemp fibers, cellulose fibers, and aramid fibers, and the non-fibrous filler is at least one selected from alumina, carbon black, clay, zirconium phosphate, kaolin, calcium carbonate, copper powder, diatomaceous earth, graphite, mica, silica, titanium dioxide, zeolite, talc, wollastonite, glass beads, and glass powder.

[0019] The polyamide molding composition of the present invention can be used in the manufacture of various electronic connector devices requiring SMT (surface mount technology), such as USB, Type-C, and DDR. These electronic devices have high demands regarding the melting point, water absorption rate, and dimensional stability of the materials, and are widely used in fields such as electronics, electrical engineering, and automotive. [Advantages of the Invention]

[0020] The present invention has the following beneficial effects compared with the prior art. 1. In the flangic carboxylic acid-based polyamide of the present invention, all the diacid units contain rigid rings, and cyclohexane has higher rigidity than the aromatic ring, and more rigid carbon layers can be formed when burning. Furthermore, the polyamide resin of the present invention has a high amide bond density and exhibits excellent synergistic effects when used in combination with a flame retardant, so the flame retardant effect is good. 2. In the present invention, by adjusting the ratio of flangic carboxylic acid to cyclohexanedicarboxylic acid, a flangic carboxylic acid-based polyamide having a melting point in the range of 290 to 336 °C and having good heat resistance and processability can be produced. 3. The flangic carboxylic acid-based polyamide of the present invention has the advantages of low water absorption rate and high dimensional stability. [Modes for Carrying Out the Invention]

[0021] Hereinafter, the present invention will be described in detail with reference to specific examples. The following examples facilitate those skilled in the art to further understand the present invention, but do not limit the present invention in any form. For those skilled in the art, some modifications and improvements may be made without departing from the concept of the present invention. All of these belong to the protection scope of the present invention.

[0022] The origin of the raw materials used in the present invention is as follows. 2,5-Furandicarboxylic acid: purity 98%, purchased from Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences 1,4-Cyclohexanedicarboxylic acid: purity 98%, purchased from Sigma-Aldrich 1,6-Adipic acid: purity 98%, purchased from Sigma-Aldrich Terephthalic acid: purity 98%, purchased from Sigma-Aldrich 1,10-Decanediamine: purity 98%, purchased from Wuxi Yindani Long Co., Ltd. 1,5-Pentylenediamine: 98% purity, purchased from Shanghai Kaisai Chemical Co., Ltd. 1,6-Hexamethylenediamine: 98% purity, purchased from Sigma-Aldrich. Benzoic acid: Pure for analytical use, purchased from Sigma-Aldrich. Sodium hypophosphite: Pure for analytical use, purchased from Sigma-Aldrich. Non-halogen flame retardant A: Aluminum diethylphosphinate, OP1230, phosphorus content 23-24% by mass, purchased from Clariant. Non-halogen flame retardant B: Melamine polyphosphate MELAPUR200-70, nitrogen content 42-44%, phosphorus content 12-14%, purchased from BASF. Reinforcement material: Fiberglass, ECS11-4.5-560A, average diameter 11 microns, purchased from Chinese megaliths.

[0023] The polyamide resins of the examples and comparative examples are obtained by the following similar method. The reaction materials (diamine, diacid) are added in the proportions shown in the table to a pressure vessel equipped with a magnetic coupling stirrer, condenser tube, gas phase port, supply port, and pressure-resistant explosion-proof port. Then, benzoic acid, sodium hypophosphite (catalyst), and deionized water are added so that the amount of benzoic acid is 2% of the total weight of the diamine and diacid, the weight of sodium hypophosphite is 0.08% of the weight of the other input materials other than deionized water, and the weight of deionized water is 25% of the total weight of the input materials. Vacuum is then applied, a protective gas is introduced as high-purity nitrogen, and the mixture is stirred for 2 hours. The mixture is heated to 30°C, the reaction mixture is stirred at 220°C for 0.5 to 2 hours, then the temperature of the reactants is raised to 240°C while stirring, and the reaction is sustained at a constant temperature of 240°C and a constant pressure of 2.3 MPa for 1 to 3 hours. The formed water is removed and the pressure is kept constant. After the reaction is complete, the materials are discharged, the prepolymer is vacuum-dried at 70 to 90°C to obtain a prepolymerization product, and the prepolymerization product is thickened in solid phase at 260°C and under a vacuum of 50 Pa for 8 to 12 hours to obtain a frangic acid-based polyamide (a polyamide that does not contain frangic acid).

[0024] Test method:

[0025] (1) Test method for the relative viscosity of polyamide resin: Refer to GB12006.1-89 for the method of measuring the viscosity of polyamide. Specific test method: The relative viscosity ηr of polyamide at a concentration of 0.25 g / dl is measured in 98% concentrated sulfuric acid at 25 ± 0.01 °C.

[0026] (2) Method for testing the melting point of polyamides: Refer to ASTM D3418-2003, Standard Test Method for Transition Temperatures of Polymers By Differential Scanning Calorimetry. Specific test method: The melting point of the sample is tested using a Perkin Elmer Dimond DSC analyzer. The atmosphere is nitrogen and the flow rate is 50 mL / min. In the test, the temperature is first raised to 350°C at 20°C / min, and the sample is held at 350°C for 2 minutes to remove the thermal history of the resin. Then, it is cooled to 50°C at 20°C / min, held at 50°C for 2 minutes, and then the temperature is raised again to 350°C at 20°C / min. The endothermic peak temperature at this point is defined as the melting point Tm.

[0027] (3) Water absorption rate of polyamide: The sample is injection molded into a 20mm x 20mm x 2mm sample, and its weight is set to a0. Then, it is placed in water at 95°C for 240 hours, and its weight is set to a1. However, the water absorption rate = (a1 - a0) / a0 * 100%.

[0028] (4) Shrinkage rate of polyamide: The sample is injection molded into a 20 mm × 10 mm × 2 mm sample plate, and then placed in water at 95°C for 240 hours. After that, the shrinkage rate after water absorption is measured according to ISO 294-4-2018 standard.

[0029] (5) Flame retardancy: Referring to the UL94 V-0 test standard, the dimensions of the standard rod-shaped test specimen are 125±5 mm in length, 13.0±0.5 mm in width, and 0.8 mm in thickness. Five test specimens are treated at 23±2°C and 50±5% for a minimum of 48 hours. The flame of the Bunsen burner is aligned with the center of the lower end of the test specimen, and the distance between the center of the top surface of the Bunsen burner tube and the lower end surface of the test specimen is maintained at 10±1 mm, and this distance is maintained at 10±0.5 S. If necessary, the Bunsen burner can be moved according to changes in the length and position of the test specimen. Immediately after applying the flame to the test specimen for 10±0.5 S, the Bunsen burner was moved at a speed of approximately 300 mm / s to a distance of at least 150 mm from the test specimen. At the same time, the flaming burning time T1 (in s) of the test specimen is measured using a timing device. After the flame burning of the test specimen has stopped, even if the Bunsen burner has not been moved 150 mm away from the specimen, immediately maintain a distance of 10 ± 1 mm from the nozzle of the Bunsen burner to the lower end surface of the specimen, apply the flame again for 10 ± 0.5 S, remove the Bunsen burner when necessary to remove any drips, and immediately move the Bunsen burner at least 150 mm away from the specimen after applying the flame, simultaneously start the timing device to measure the flame burning time T2 and flameless burning time T3 of the specimen, and record T2 and T3. If all five splines have T1 + T2 + T3 < 10 S and no drips ignite the cotton below, the V-0 condition is considered to be met.

[0030] [Table 1]

[0031] As can be seen from Examples 1 to 6, the higher the content of 1,4-cyclohexanedicarboxylic acid, the higher the melting point and the lower the water absorption and shrinkage rate.

[0032] [Table 2]

[0033] Comparative Example 1 / 2, a flanger carboxylic acid-based polyamide resin, has no practical use because its melting point exceeds its decomposition temperature.

[0034] As can be seen from Comparative Example 3, the higher the content of 2,5-franzicarboxylic acid, the higher the water absorption rate and shrinkage rate, the lower the melting point, and the lower the value of use.

[0035] As can be seen from Comparative Example 6, when cyclohexanedioic acid is replaced with adipic acid, even if the amide bond density decreases, the water absorption rate increases, the shrinkage rate worsens, and the melting point is too low.

[0036] As can be seen from Comparative Example 7, when cyclohexanedioic acid is replaced with terephthalic acid, which has a similar structure, the water absorption rate is too high or the shrinkage rate is too low.

[0037] As can be seen from Comparative Example 8, the frangic acid / cyclohexanedioic acid / pentylenediamine segment polyamide exhibits inferior shrinkage.

[0038] [Table 3]

[0039] Examples 9 ~ 16 As can be seen more clearly, the flanger carboxylic acid-based polyamide composition of the present invention has good flame retardancy.

[0040] [Table 4]

[0041] As can be seen from Comparative Examples 9-11, if the melting point is too high or too low, modification and processing / molding become impossible.

[0042] As can be seen from Comparative Examples 12, 13, 15, and 16, when 1,4-cyclohexanedicarboxylic acid or 1,5-pentylenediamine is replaced with other diamines, the franc carboxylic acid-based polyamide composition or other polyamide compositions exhibit poor flame retardancy and high lateral and longitudinal shrinkage.

Claims

1. It is derived from repeating units comprising (A) 2,5-franzicarboxylic acid, (B) 1,4-cyclohexanedicarboxylic acid, and (C) 1,10-decanediamine, characterized in that (A) accounts for 5 to 45 mol% of the total molar percentage of the diacid units. Flange carboxylic acid-based polyamide resin.

2. The frangic acid-based polyamide resin according to claim 1, characterized in that (A) accounts for 5 to 25 mol% of the total molar percentage of diacid units.

3. The frangic acid-based polyamide resin according to claim 2, characterized in that (A) accounts for 5 to 15 mol% of the total molar percentage of diacid units.

4. The flange carboxylic acid-based polyamide resin according to claim 1, characterized in that the relative viscosity of the flange carboxylic acid-based polyamide resin is 1.8 to 2.

4.

5. The flange carboxylic acid-based polyamide resin according to claim 1, characterized in that the flange carboxylic acid-based polyamide resin has a melting point of 290 to 336°C.

6. The flange carboxylic acid-based polyamide resin according to claim 1, characterized in that the water absorption rate of the flange carboxylic acid-based polyamide resin is 1.5% or less, and the lateral / vertical shrinkage rate of the flange carboxylic acid-based polyamide resin is 0.2% / 0.5% or less.

7. The process involves adding the reaction materials to a pressure vessel in predetermined proportions, then adding benzoic acid, sodium hypophosphate, and deionized water such that the amount of benzoic acid is 2-3 mol% of the total amount of diamine and diacid, the weight of sodium hypophosphate is 0.05-0.15% of the weight of the other input materials other than deionized water, and the weight of deionized water is 25-35% of the total weight of the input materials, then introducing a protective gas as high-purity nitrogen under vacuum suction, raising the temperature to 210-230°C within 2 hours while stirring, stirring the reaction mixture at 210-230°C for 0.5-2 hours, and then stirring... A method for producing a frangic acid-based polyamide resin according to any one of claims 1 to 6, comprising the steps of: raising the temperature of the reactants to 220 to 240°C, sustaining the reaction at a constant temperature of 220 to 240°C and a constant pressure of 2.1 to 2.3 MPa for 1 to 3 hours, removing the formed water and maintaining a constant pressure, discharging the materials after the reaction is complete, vacuum drying the prepolymer at 70 to 90°C to obtain a prepolymerization product, and thickening the prepolymerization product in solid phase for 8 to 12 hours under vacuum conditions of 240 to 260°C and 40 to 60 Pa to obtain a frangic acid-based polyamide resin.

8. A polyamide molding composition comprising, with respect to 100 parts by weight of the polyamide molding composition, 40 to 70 parts by weight of the flange carboxylic acid-based polyamide resin according to any one of claims 1 to 6, 10 to 30 parts by weight of a non-halogen flame retardant, A polyamide molding composition characterized by comprising 0 to 50 parts by weight of a reinforcing material.

9. The non-halogen flame retardant is at least one selected from phosphine-based flame retardants, phosphinate-based flame retardants, hypophosphorite-based flame retardants, phosphonite-based flame retardants, phosphotite-based flame retardants, phosphite-based flame retardants, phosphine oxide-based flame retardants, phosphinate-based flame retardants, hypophosphorite-based flame retardants, phosphonate-based flame retardants, phosphonate-based flame retardants, phosphate-based flame retardants, polyphosphate-based flame retardants, or phosphinate-based flame retardants, and the hypophosphinate-based flame retardant is at least one selected from aluminum hypophosphite or calcium hypophosphite, and the phosphinate-based flame retardant is at least one selected from aluminum hypophosphite or calcium hypophosphite. The polyamide molding composition according to claim 8, characterized in that the flammable agent is at least one selected from aluminum dimethylphosphinate, aluminum diethylphosphinate, or aluminum methylethylphosphinate; the phosphate-based flame retardant is at least one selected from bisphenol A bis(diphenyl phosphate), resorcinol(diphenyl phosphate), triphenyl phosphate, or melamine phosphate; and the polyphosphate-based flame retardant is at least one selected from ammonium polyphosphate, melamine polyphosphate, melamine pyrophosphate, or melamine polyphosphate.

10. The polyamide molding composition according to claim 8, characterized in that the reinforcing material is at least one selected from fibrous fillers and non-fibrous fillers; the fibrous filler is at least one selected from glass fibers, carbon fibers, basalt fibers, bamboo fibers, hemp fibers, cellulose fibers, or aramid fibers, and the non-fibrous filler is at least one selected from alumina, carbon black, clay, zirconium phosphate, kaolin, calcium carbonate, copper powder, diatomaceous earth, graphite, mica, silica, titanium dioxide, zeolite, talc, wollastonite, glass beads, or glass powder.

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