CN113817157B - Semi-aromatic polyamide polycondensation catalyst and preparation method thereof - Google Patents

Abstract

The invention relates to a semi-aromatic polyamide polycondensation catalyst and a preparation method thereof, belonging to the technical field of polymer synthesis. The invention provides a preparation method of a semi-aromatic polyamide polycondensation catalyst, which comprises the following steps: preparing a semi-aromatic polyamide polycondensation catalyst by a complexing reaction of a macromolecular ligand, a metal compound and an organic phosphine compound; wherein the macromolecular ligand is a substance capable of carrying out a complex reaction with a metal compound; the mass ratio of the raw materials is as follows: 70-130 parts of polymer ligand, 0.1-10 parts of metal compound and 1-50 parts of organic phosphine compound. The invention provides a novel semi-aromatic polyamide polycondensation catalyst and a preparation method thereof, and the obtained catalyst has the advantages of high catalytic efficiency and low cost; the invention adopts a one-pot process, and has the advantages of simple operation and high yield.

Description

A kind of semi-aromatic polyamide polycondensation catalyst and preparation method thereof

technical field

The invention relates to a semi-aromatic polyamide polycondensation catalyst and a preparation method thereof, which are mainly used for the synthesis of semi-aromatic polyamide and belong to the technical field of polymer synthesis.

Background technique

Semi-aromatic polyamide is a kind of polymer material with excellent performance, which has the advantages of high temperature resistance, corrosion resistance and low water absorption, and has been widely used in the fields of electronic appliances, machinery manufacturing and automobile industry. In recent years, bio-based polymers have become more and more popular among consumers around the world as carbon-neutral products. Polypentamethylene terephthalamide (PA5T) can be obtained by fermenting agricultural products to prepare pentamethylene diamine, and then polycondensing it with terephthalic acid. PA5T is a partially bio-based semi-aromatic polyamide with excellent comprehensive properties and is expected to be widely used in future production and life.

Semi-aromatic polyamides generally use aromatic dibasic acids, aliphatic dibasic acids and diamines under the action of phosphorus-containing catalysts to undergo high-temperature solution polycondensation in an aqueous solution, and further solid-phase polycondensation or melt polycondensation to prepare high molecular weight semi-aromatic family of polyamide resins. For example, Chinese patents CN102532528A and CN110423344A all report the preparation of semi-aromatic polyamides using phosphoric acid, polyphosphoric acid, sodium phosphite and sodium hypophosphite as catalysts. However, in the synthesis of PA5T, when using traditional phosphorus-based catalysts, pentamethylenediamine is easily deaminated and cyclized to form hexahydropyridine (piperidine) at high temperature, resulting in an unbalanced monomer ratio and a decrease in molecular weight. The final PA5T The performance deteriorated and the yield decreased.

Therefore, it is very necessary to develop a catalyst that can be used to prepare semi-aromatic polyamides such as PA5T.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a kind of semi-aromatic polyamide polycondensation catalyst (that is, the catalyst for preparing semi-aromatic polyamide) and its preparation method for the deficiencies of the prior art, and the obtained catalyst has high catalytic efficiency and low cost. and the present invention adopts a one-pot process, which has the advantages of simple operation and high yield.

Technical solution of the present invention

The first technical problem to be solved by the present invention is to provide a preparation method of a semi-aromatic polyamide polycondensation catalyst. Aromatic polyamide polycondensation catalyst; wherein, the polymer ligand is a substance capable of complex reaction with a metal compound; the mass ratio of each raw material is: 70-130 parts by weight of the polymer ligand and 0.1-10 parts by weight of the metal compound parts, 1 to 50 parts by weight of the organic phosphine compound.

Further, the macromolecular ligand is prepared by the following method: adding unsaturated carboxylic acid, comonomer, deionized water and ammonia water to itaconic acid, and preparing by free radical polymerization under the action of an oxidizing agent and a reducing agent. The polymer ligand is obtained; wherein, 1.57-19.7 parts by weight of itaconic acid, 58-86 parts by weight of unsaturated carboxylic acid, 0.99-13 parts by weight of comonomer, 31-47 parts by weight of ammonia water, and 0.05-2 parts by weight of oxidant parts by weight, 0.07-1.7 parts by weight of reducing agent.

Further, the itaconic acid is at least one of the substances represented by the following structural formula;

中的至少一种。where R=

at least one of them.

Further, the itaconic acid is a product obtained by reacting itaconic anhydride and aliphatic secondary amine in a molar ratio of 1:1.

Further, the aliphatic secondary amine is at least one of dimethylamine, diethylamine, tetrahydropyrrole or hexahydropyridine.

Further, the unsaturated carboxylic acid is at least one of acrylic acid, methacrylic acid, maleic acid, transbutenedioic acid or itaconic acid.

Further, the comonomer is at least one of hydroxyethyl acrylate, hydroxyethyl methacrylate, N,N-dimethylacrylamide or N,N-dimethylmethacrylamide.

Further, the oxidant is any one of hydrogen peroxide, tert-butyl hydroperoxide or cumene hydrogen peroxide.

Further, the reducing agent is any one of oxalic acid, furfural, 5-hydroxymethylfurfural or glucose.

Further, the metal compound is zinc sulfate, zinc chloride, zinc nitrate, zinc acetate, zinc carbonate, basic zinc carbonate, zinc hydroxide, zinc oxide, copper sulfate, copper chloride, copper nitrate, copper acetate, basic zinc At least one of copper carbonate, copper hydroxide, copper oxide, cuprous chloride, cuprous oxide, nickel sulfate, nickel dichloride, nickel nitrate, nickel carbonate, nickel hydroxide or nickel oxide.

Further, the organic phosphine compound is triphenylphosphine, triphenylphosphine oxide, tris(2-thienyl)phosphine, tris(2-furyl)phosphine, P,P-diphenyl-2-phosphine pyridine, P,P,P',P'-tetraphenyl-1,2-diphosphinobenzene, P,P,P',P'-tetraphenyl-1,8-diphosphinaphthalene, P,P,P' ,P'-tetraphenyl-2,2'-diphosphine biphenyl, P,P,P',P'-tetraphenyl-2,2'-diphosphine diphenyl ether or P,P,P', At least one of P'-tetraphenyl-1,1'-diphosphinoferrocene.

Further, the complex reaction process is as follows: the polymer ligand, the metal compound, the organic phosphine compound and the ammonia water are mixed uniformly, and the reaction is stirred at 50-90° C. for 1-3 hours under the protection of an inert gas.

Further, the preparation method of the semi-aromatic polyamide polycondensation catalyst comprises the following steps:

(1) Add 1.12-11.2 parts of itaconic anhydride and 5-30 parts of solvent to the reaction kettle, feed an inert gas (such as nitrogen), and stir; pass water for cooling, add 0.45-8.5 parts of aliphatic secondary amine, and maintain the temperature at The reaction is carried out over 50°C for 0.5 to 2 hours to obtain itaconic acid reaction solution;

(2) 58～86 parts of unsaturated carboxylic acids and 200～500 parts of deionized water are added to the obtained itaconic acid reaction solution, and 31～47 parts of ammonia water whose mass concentration is 20～28% are added, and the maintenance temperature is not more than 50 ℃ reaction 0.5～1h;

(3) open the reaction kettle, add 0.99～13 parts of comonomer, 0.05～2 parts of oxidant and 0.07～1.7 parts of reducing agent in turn; stir, stop the inert gas, close the reaction kettle, and keep reacting at 60～90 ℃ for 0.5～ After 3 hours, a polymer ligand reaction solution was obtained;

(4) cooling the above-mentioned polymer ligand reaction solution to 40～60℃, adding 0.1～10 parts of metal compound, 1～50 parts of organic phosphine compound and 34～52 parts of ammonia water with mass concentration of 20～28%; Inert gas, stirring, the reaction is kept at 50～90℃ for 1～3 hours;

(5) cooling to room temperature, shutting off the inert gas, discharging, and drying the product to a moisture content of ≤1% to obtain a semi-aromatic polyamide polycondensation catalyst.

Further, in step (1), the solvent is any one of N,N-dimethylacetamide, N-methyl-2-pyrrolidone or 1,3-dimethyl-2-imidazolidinone.

Further, in step (3), the oxidant is any one of hydrogen peroxide, tert-butyl hydroperoxide or cumene hydroperoxide.

Further, in step (3), the reducing agent is any one of oxalic acid, furfural, 5-hydroxymethylfurfural or glucose.

The second technical problem to be solved by the present invention is to provide a semi-aromatic polyamide polycondensation catalyst, which is prepared by the above method.

In the present invention, the raw material parts are all parts by weight unless otherwise specified.

Beneficial effects of the present invention:

1. The catalyst of the present invention can effectively reduce the side reaction of deamination and cyclization of diamines such as pentamethylene diamine in the high-temperature polycondensation process, and has the advantages of strong selectivity and few by-products.

2. The catalyst of the present invention has high catalytic efficiency, less addition, low content of aliphatic polycarboxylate introduced into the polymerization system, very limited cross-linking effect on semi-aromatic polyamide, and will not affect the performance of semi-aromatic polyamide .

3. The polymer ligands of the present invention are synthesized from common monomers as raw materials, and the used metal compounds are common compounds, which have the advantages of wide source of raw materials and low cost.

4. The present invention is simple in operation, mature in technology and stable in quality of the obtained product.

Detailed ways

The invention prepares a novel catalyst for preparing semi-aromatic polyamide: firstly using itaconic acid anhydride and aliphatic secondary amine as raw materials to prepare itaconic acid in a polar aprotic solvent; Add unsaturated carboxylic acid, comonomer, deionized water and ammonia water to amic acid, and free radical polymerization under the action of oxidation-reduction initiator to obtain macromolecular ligand; then add metal compound, triphenylphosphine and ammonia water to carry out Complexation reaction, drying treatment to obtain semi-aromatic polyamide polycondensation catalyst. The invention adopts a one-pot method, which has the advantages of simple operation and high yield, and the obtained catalyst has the advantages of high catalytic efficiency and low cost.

The present invention will be specifically described by the following examples. It is necessary to point out that this example is only used to further illustrate the present invention, and should not be construed as a limitation on the scope of the present invention. Those skilled in the art can Some non-essential improvements and adjustments are made to the content of the invention.

Example 1

5.6g of itaconic anhydride and 15g of N-methyl-2-pyrrolidone were added to the reaction kettle, nitrogen was introduced, and stirred; cooled with water, 3.65g of diethylamine was added, and the temperature was maintained at 50°C for 1 hour; 86g of methyl alcohol was added. base acrylic acid, 350g deionized water and 39g ammonia water with a mass concentration of 24%, maintaining the temperature not more than 50 ° C for 0.5 hours; opening the reaction kettle, adding 6.5g hydroxyethyl methacrylate, 0.5g mass fraction of 30% Hydrogen peroxide and 1g glucose, stop nitrogen gas, close the reaction kettle, and keep the reaction at 70°C for 2 hours; then cool down to 50°C, continue to add 3g copper sulfate, 20g triphenylphosphine and 43g ammonia water with a mass concentration of 24%, Nitrogen was introduced, stirred, and reacted at 90° C. for 3 hours; then cooled to room temperature, discharged, and the product was dried to a water content of ≤1% to obtain a semi-aromatic polyamide polycondensation catalyst.

15g of the catalyst prepared in Example 1, 1129g of terephthalic acid, 467g of adipic acid, 1030g of pentanediamine and 800g of deionized water were added to the reactor, the stirring was started, and the air in the reactor was replaced with nitrogen 3 times; the reactor was closed. , heat up to 230 °C within 1.5 hours, and keep the reaction for 2 hours; open the exhaust valve, discharge the water vapor in the kettle to normal pressure within 1 hour, and maintain the temperature not more than 330 °C; continue to vacuum to -0.08MPa, at 320 °C The reaction was kept for 3 hours; high pressure nitrogen was charged, the bottom valve of the reactor was opened, the casting tape was discharged, and the semi-aromatic polyamide resin was obtained after cooling and drying. The intrinsic viscosity [η] of the obtained resin was 0.88 dL·g ⁻¹ , and the resin yield was 97%.

The performance parameters of the semi-aromatic polyamide obtained in each example and comparative example are shown in Table 1. In the embodiment of the present invention, concentrated sulfuric acid is used as the solvent for the intrinsic viscosity test, the sample concentration is 0.50g/dL, and it is measured in a Ubbelohde viscometer at 30±0.1°C, and is calculated by the one-point method.

Example 2

2.24g of itaconic anhydride and 10g of N,N-dimethylacetamide were added to the reaction kettle, nitrogen was introduced, and stirred; cooled with water, 1.36g of dimethylamine aqueous solution with a mass fraction of 33% and 0.85g of hexahydropyridine were added. , keep the temperature not more than 50 ℃ and react for 1.5 hours; add 72g acrylic acid, 250g deionized water and 35g ammonia water with a mass concentration of 25%, maintain the temperature not more than 50 ℃ and react for 1 hour; open the reaction kettle, add 0.58g hydroxyethyl acrylate in turn Ester, 0.50g N,N-dimethylacrylamide, 1.2g cumene hydroperoxide and 0.8g furfural, stop nitrogen gas, close the reaction kettle, and keep the reaction at 80°C for 1 hour; cool down to 40°C, continue to add 1g of zinc chloride, 8g of triphenylphosphine, 2g of P,P,P',P'-tetraphenyl-1,2-diphosphine benzene and 39g of ammonia water with a mass concentration of 25% were introduced into nitrogen, stirred, The reaction is kept at 60 DEG C for 2 hours; then it is lowered to room temperature, the material is discharged, and the product is dried to a moisture content of ≤1% to obtain a semi-aromatic polyamide polycondensation catalyst.

The catalyst prepared by 20g embodiment 2, 1162g terephthalic acid, 498g isophthalic acid, 1032g pentamethylene diamine and 1000g deionized water were added to the reaction kettle, and stirring was started, and the air in the kettle was replaced by nitrogen for 2 times; closed reaction The kettle was heated to 220 °C within 1 hour, and the reaction was kept for 3 hours; the exhaust valve was opened, and the water vapor in the kettle was discharged to normal pressure within 1.5 hours, and the temperature did not exceed 330 °C; The reaction is kept at ℃ for 4 hours; high pressure nitrogen is charged, the bottom valve of the reactor is opened, the casting tape is discharged, and the semi-aromatic polyamide resin is obtained after cooling and drying. Intrinsic viscosity [η]=0.86 dL·g ⁻¹ , and resin yield was 98%.

Example 3

1.12g of itaconic anhydride and 7g of 1,3-dimethyl-2-imidazolidinone were added to the reaction kettle, nitrogen was introduced, and stirred; cooled with water, 2.25g of dimethylamine aqueous solution with a mass fraction of 20% was added to maintain The temperature did not exceed 50°C for 0.5 hours; 68.8g methacrylic acid, 5.8g maleic acid, 6.5g itaconic acid, 220g deionized water and 32g ammonia water with a mass concentration of 27% were added to react for 1 hour, maintaining the temperature Do not exceed 50 ° C; open the reaction kettle, add 4.64 g of hydroxyethyl acrylate, 0.9 g of tert-butyl hydroperoxide and 0.7 g of oxalic acid in turn, stop nitrogen gas, close the reaction kettle, and keep the reaction at 90 ° C for 2 hours; cool down to 50 ℃, continue to add 0.2g nickel dichloride, 4g triphenylphosphine oxide, 0.5g tris(2-furyl)phosphine, 0.5g P,P,P',P'-tetraphenyl-1,1'- Diphosphinoferrocene and 35 g of ammonia water with a mass concentration of 27% were introduced into nitrogen, stirred, and reacted at 80°C for 1 hour; then cooled to room temperature, discharged, and the product was dried to a water content of ≤1% to obtain a half Aromatic polycondensation catalyst.

10g of the catalyst prepared in Example 3, 1129g of terephthalic acid, 531g of isophthalic acid, 892g of butanediamine and 1200g of deionized water were added to the reaction kettle, and stirring was started, and the air in the kettle was replaced with nitrogen 3 times; closed reaction The kettle was heated to 240 °C within 2 hours, and the reaction was kept for 2 hours; the exhaust valve was opened, and the water vapor in the kettle was discharged to normal pressure within 2 hours, and the temperature was maintained at no more than 330 °C; The reaction is kept at ℃ for 4 hours; high pressure nitrogen is charged, the bottom valve of the reactor is opened, the casting tape is discharged, and the semi-aromatic polyamide resin is obtained after cooling and drying. Intrinsic viscosity [η]=0.94 dL·g ⁻¹ , and resin yield was 95%.

Comparative Example 1

15g of sodium hypophosphite, 1129g of terephthalic acid, 467g of adipic acid, 1030g of pentanediamine and 800g of deionized water were added to the reaction kettle, stirring was started, and nitrogen was used to replace the air in the kettle 3 times; The temperature was raised to 230°C, and the reaction was kept for 2 hours; the exhaust valve was opened, and the water vapor in the kettle was discharged to normal pressure within 1 hour, and the temperature was maintained at no more than 330°C; the vacuum was continued to -0.08MPa, and the reaction was kept at 320°C for 3 hours. ; Fill with high pressure nitrogen, open the bottom valve of the reactor, cast the tape to discharge, and obtain semi-aromatic polyamide resin after cooling and drying. Intrinsic viscosity [η]=0.54 dL·g ⁻¹ , and resin yield was 82%.

The performance parameters of the semi-aromatic polyamide obtained in the embodiment and comparative example of table 1

Intrinsic viscosity (dL·g^-1) Resin yield (%) Example 1 0.88 97 Example 2 0.86 98 Example 3 0.94 95 Comparative Example 1 0.54 82

Claims (10)

1. A preparation method of a semi-aromatic polyamide polycondensation catalyst is characterized by comprising the following steps: preparing a semi-aromatic polyamide polycondensation catalyst by a complexing reaction of a macromolecular ligand, a metal compound and an organic phosphine compound; wherein the macromolecular ligand is a substance capable of carrying out a complex reaction with a metal compound; the mass ratio of the raw materials is as follows: 70-130 parts of polymer ligand, 0.1-10 parts of metal compound and 1-50 parts of organic phosphine compound;

the macromolecular ligand is prepared by the following method: adding unsaturated carboxylic acid, comonomer, deionized water and ammonia water into itaconic acid, and preparing the macromolecular ligand through free radical polymerization under the action of oxidant and reducer; wherein, 1.57 to 19.7 parts by weight of itaconic acid, 58 to 86 parts by weight of unsaturated carboxylic acid, 0.99 to 13 parts by weight of comonomer, 31 to 47 parts by weight of ammonia water, 0.05 to 2 parts by weight of oxidant and 0.07 to 1.7 parts by weight of reducer; the unsaturated carboxylic acid is at least one of acrylic acid, methacrylic acid, cis-butenedioic acid, trans-butenedioic acid and itaconic acid; the comonomer is at least one of hydroxyethyl acrylate, hydroxyethyl methacrylate, N-dimethylacrylamide or N, N-dimethylmethacrylamide; the itaconic acid is at least one of the substances shown in the following structural formula;

wherein

At least one of;

the metal compound is at least one of zinc sulfate, zinc chloride, zinc nitrate, zinc acetate, zinc carbonate, basic zinc carbonate, zinc hydroxide, zinc oxide, copper sulfate, copper chloride, copper nitrate, copper acetate, basic copper carbonate, copper hydroxide, copper oxide, cuprous chloride, cuprous oxide, nickel sulfate, nickel dichloride, nickel nitrate, nickel carbonate, nickel hydroxide or nickel oxide;

the organic phosphine compound is at least one of triphenylphosphine, triphenylphosphine oxide, tris (2-thienyl) phosphine, tris (2-furyl) phosphine, P, P-diphenyl-2-phosphinpyridine, P, P, P ', P ' -tetraphenyl-1, 2-diphosphinobenzene, P, P, P ', P ' -tetraphenyl-1, 8-diphosphinonaphthalene, P, P, P ', P ' -tetraphenyl-2, 2 ' -diphosphinobiphenyl, P, P, P ', P ' -tetraphenyl-2, 2 ' -diphosphinodiphenyl ether or P, P, P ', P ' -tetraphenyl-1, 1 ' -diphosphinoferrocene.

2. The method of preparing a semi-aromatic polyamide polycondensation catalyst according to claim 1, wherein the itaconamic acid is a product obtained by reacting itaconic anhydride and an aliphatic secondary amine.

3. The method of preparing a semi-aromatic polyamide polycondensation catalyst according to claim 2, wherein the aliphatic secondary amine is at least one of dimethylamine, diethylamine, tetrahydropyrrole or piperidine.

4. The method for preparing a semi-aromatic polyamide polycondensation catalyst according to claim 1, wherein the oxidizing agent is any one of hydrogen peroxide, tert-butyl hydroperoxide, or cumene hydroperoxide;

the reducing agent is any one of oxalic acid, furfural, 5-hydroxymethylfurfural or glucose.

5. The method for preparing a semi-aromatic polyamide polycondensation catalyst according to any one of claims 1 to 4, wherein the complexation reaction process is: the polymer ligand, the metal compound, the organic phosphine compound and ammonia water are uniformly mixed, and stirred and reacted for 1-3 hours at 50-90 ℃ under the protection of inert gas.

6. The method of preparing a semi-aromatic polyamide polycondensation catalyst according to claim 4, wherein the method of preparing a semi-aromatic polyamide polycondensation catalyst comprises the steps of:

(1) adding 1.12-11.2 parts of itaconic anhydride and 5-30 parts of solvent into a reaction kettle, introducing inert gas, and stirring; cooling with water, adding 0.45-8.5 parts of aliphatic secondary amine, and reacting for 0.5-2 h while maintaining the temperature not to exceed 50 ℃ to obtain an itaconic acid reaction solution;

(2) adding 58-86 parts of unsaturated carboxylic acid and 200-500 parts of deionized water into the obtained itaconic acid reaction liquid, adding 31-47 parts of ammonia water with the mass concentration of 20-28%, and reacting for 0.5-1 h at the temperature not higher than 50 ℃;

(3) opening the reaction kettle, and sequentially adding 0.99-13 parts of comonomer, 0.05-2 parts of oxidant and 0.07-1.7 parts of reducing agent; stirring, stopping introducing inert gas, sealing the reaction kettle, and carrying out heat preservation reaction at 60-90 ℃ for 0.5-3 hours to obtain a polymer ligand reaction solution;

(4) cooling the obtained polymer ligand reaction liquid to 40-60 ℃, and adding 0.1-10 parts of metal compound, 1-50 parts of organic phosphine compound and 34-52 parts of ammonia water with mass concentration of 20-28%; introducing inert gas, stirring, and reacting for 1-3 hours at the temperature of 50-90 ℃;

(5) cooling to room temperature, stopping introducing the inert gas, discharging, and drying the product until the water content is less than or equal to 1% to obtain the semi-aromatic polyamide polycondensation catalyst.

7. The method of preparing a semi-aromatic polyamide polycondensation catalyst according to claim 6, wherein in step (1), the solvent is any one of N, N-dimethylacetamide, N-methyl-2-pyrrolidone, or 1, 3-dimethyl-2-imidazolidinone.

8. The method of preparing a semi-aromatic polyamide polycondensation catalyst according to claim 6, wherein in step (3), the oxidizing agent is any one of hydrogen peroxide, tert-butyl hydroperoxide, or cumene hydroperoxide.

9. The method of preparing a semi-aromatic polyamide polycondensation catalyst according to claim 6, wherein in step (3), the reducing agent is any one of oxalic acid, furfural, 5-hydroxymethylfurfural, or glucose.

10. A semi-aromatic polyamide polycondensation catalyst, characterized in that the semi-aromatic polyamide polycondensation catalyst is obtained by the method according to any one of claims 1 to 9.