CN115710350A

CN115710350A - Preparation method and application of aliphatic-aromatic copolyester

Info

Publication number: CN115710350A
Application number: CN202210304779.0A
Authority: CN
Inventors: 李凌云; 张长礼
Original assignee: Xuke New Materials Shandong Co ltd; Polycarbon Oxygen New Material Technology Wuxi Co ltd
Current assignee: Xuke New Materials Shandong Co ltd; Polycarbon Oxygen New Material Technology Wuxi Co ltd
Priority date: 2022-03-22
Filing date: 2022-03-22
Publication date: 2023-02-24
Anticipated expiration: 2042-03-22
Also published as: CN115710350B

Abstract

The invention provides a preparation method and application of aliphatic-aromatic copolyester, wherein the preparation method comprises the following steps: respectively carrying out esterification reaction, polycondensation reaction and chain growth reaction on aliphatic dibasic acid and aromatic dibasic acid and aliphatic dihydric alcohol in the presence of a first catalyst and/or a second catalyst to obtain aliphatic-aromatic copolyester; wherein the first catalyst comprises a reaction product of a titanium-containing compound, a magnesium-containing compound, a zinc-containing compound, a hydroxyl-containing compound, and a carboxyl-containing compound; the second catalyst comprises a reaction product of a titanium-containing compound, a magnesium-containing compound, a zinc-containing compound, a hydroxyl-containing compound, and an epoxy-containing compound. The auxiliary agent used in the chain extension reaction comprises a molecular weight extender, and the molecular weight extender comprises isocyanate compounds. The preparation method has low cost and low energy consumption, and the prepared aliphatic-aromatic copolyester product is stable and excellent in quality, low in carboxyl end group content, few in gel point, high in molecular weight and easy to biodegrade.

Description

Preparation method and application of aliphatic-aromatic copolyester

Technical Field

The invention relates to a preparation method and application of aliphatic-aromatic copolyester.

Technical Field

At present, the production process of biodegradable aliphatic-aromatic copolyester film/sheet-level resin is divided into esterification, polycondensation and tackifying reaction. The copolyester intermediate is subjected to in-kettle melt tackifying reaction in a biaxial tackifying reaction device under the conditions of high temperature and high vacuum, and the film/sheet grade polyester resin can be prepared. However, this melt-tacking process has the following problems: 1. the vacuum degree requirement is high, the polyester viscosity is high, and the like, so that the requirement on tackifying equipment is high, the investment cost is high, and the energy consumption is high; 2. the long-time high-temperature tackifying reaction can cause side reactions such as thermal degradation reaction, local excessive reaction and the like, and the product quality is poor (the terminal carboxyl group is high, and the gel point of a product film/sheet is more).

The Chinese patent application with publication number CN103497316A discloses that a polyepoxy compound is added in the polymerization process to carry out melt tackifying reaction, and a polyester product with terminal carboxyl of 5-20 mmol/kg can be prepared. In chinese patent application publication No. CN103665777A, it is disclosed that a low-end carboxyl polyester product can be prepared by mixing, melting and extruding a polyester intermediate and a reaction auxiliary agent by using co-rotating twin screws. Chinese patent application publication No. CN 111363131A discloses a dynamic mixer for melt mixing and solid phase tackifying to prepare low-end carboxyl aliphatic-aromatic copolyester. The above patents all adopt the liquid phase melt tackifying reaction or liquid phase melt mixing to prepare high molecular weight and low end carboxyl polyester products. However, none of these patents address the problem of local excessive gel reaction during high temperature melt tacking, resulting in multiple gel points on the product film/sheet material.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a preparation method of aliphatic-aromatic copolyester, which has the advantages of low equipment cost and low energy consumption, and the prepared aliphatic-aromatic copolyester product is stable and excellent in quality, low in carboxyl end group content, few in gel point, high in molecular weight and easy to biodegrade.

The first aspect of the present invention provides a method for preparing an aliphatic-aromatic copolyester, comprising the steps of:

s1: respectively carrying out esterification reaction on aliphatic dibasic acid and aromatic dibasic acid and aliphatic dihydric alcohol in the presence of a first catalyst and/or a second catalyst, and mixing the esterification reaction products respectively obtained to obtain an esterified substance;

s2: carrying out polycondensation reaction on the esterified substance to obtain a polyester intermediate;

s3: mixing the polyester intermediate with an auxiliary agent, and carrying out a chain growth reaction to obtain the aliphatic-aromatic copolyester;

wherein the first catalyst comprises a reaction product of a titanium-containing compound, a magnesium-containing compound, a zinc-containing compound, a hydroxyl-containing compound, and a carboxyl-containing compound; the second catalyst comprises a reaction product of a titanium-containing compound, a magnesium-containing compound, a zinc-containing compound, a hydroxyl-containing compound, and an epoxy-containing compound;

the auxiliary agent comprises a molecular weight increasing agent, and the molecular weight increasing agent comprises isocyanate compounds.

According to some embodiments of the invention, the adjuvant further comprises a diffusing agent and an accelerator.

According to some embodiments of the invention, the diffusing agent comprises a compound having R ₁ -O-R ₂ An ether compound of the formula R ₁ And R ₂ Each independently selected from C ₁ ～C ₂₀ A hydrocarbyl group. In some embodiments, R ₁ And R ₂ Each independently selected from C ₁ ～C ₂₀ Alkyl radicals, e.g. C ₁ ～C ₄ Alkyl radical, C ₅ ～C ₈ Alkyl radical, C ₉ ～C ₁₂ Alkyl radical, C ₁₃ ～C ₁₆ Alkyl radical, C ₁₇ ～C ₂₀ An alkyl group. In some embodiments, R ₁ And R ₂ Each independently selected from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl or hexyl.

According to some embodiments of the invention, the diffusing agent comprises a compound having R ₃ COOR ₄ 、

One or more of ester compounds of the general formula R' and R ₃ And R ₄ Each independently selected from C ₁ ～C ₁₉ A hydrocarbon radical, G is a divalent or trivalent C ₁ ～C ₂₀ Hydrocarbyl, optionally G is substituted with hydroxy. In some embodiments, R', R ₃ And R ₄ Each independently selected from C ₁ ～C ₁₉ Alkyl radicals, e.g. C ₁ ～C ₄ Alkyl radical, C ₅ ～C ₈ Alkyl radical, C ₉ ～C ₁₂ Alkyl radical, C ₁₃ ～C ₁₆ Alkyl radical, C ₁₇ ～C ₂₀ An alkyl group. In some embodiments, R', R ₃ And R ₄ Each independently selected from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl, hexyl, heptyl, octyl. In some embodiments, G is C ₁ ～C ₂₀ Alkylene of (C) ₁ ～C ₄ Alkylene of (C) ₅ ～C ₈ Alkylene of (C) ₉ ～C ₁₂ Alkylene of (C) ₁₃ ～C ₁₆ Alkylene of (C) ₁₇ ～C ₂₀ An alkylene group of (2). In some embodiments, G is methylene, ethylene, propylene, isopropylene, butylene, isobutylene, t-butylene, n-pentylene, isopentylene, t-pentylene, hexylene, cyclopentylene, cyclohexylene, heptylene, octylene. According to some embodiments of the invention, the accelerator comprises a silicone oil having

One or more metal compounds of the formula R ₆ Is selected from C ₁ ～C ₁₉ A hydrocarbon group, M is Ti, zn, mg, sn or Al, and y is more than 1. In some embodiments, R ₆ Is selected from C ₁ ～C ₁₉ Alkyl radicals, e.g. C ₁ ～C ₄ Alkyl radical, C ₅ ～C ₈ Alkyl radical, C ₉ ～C ₁₂ Alkyl radical, C ₁₃ ～C ₁₆ Alkyl radical, C ₁₇ ～C ₁₉ . In some embodiments, R ₆ Selected from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl or hexyl. In some embodiments, y is 1,2, 3, 4, or 5.

According to some embodiments of the invention, the accelerator comprises a compound having (R) ₇ ) _z One or more metal compounds of the general formula M, R ₇ Is selected from C ₁ ～C ₂₀ A hydrocarbon group, M is Ti, zn, mg, sn or Al, and z is more than 1. In some embodiments, R ₇ Is selected from C ₁ ～C ₁₉ Alkyl radicals, e.g. C ₁ ～C ₄ Alkyl radical, C ₅ ～C ₈ Alkyl radical, C ₉ ～C ₁₂ Alkyl radical, C ₁₃ ～C ₁₆ Alkyl radical, C ₁₇ ～C ₂₀ . In some embodiments, R ₇ Selected from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl or hexyl. In some embodiments, z is 1,2, 3, 4, or 5.

According to some embodiments of the invention, the isocyanate is of the formula

Wherein R is ₅ Is C ₁ ～C ₂₀ Hydrocarbyl, x > 1. In some embodiments, R ₅ Selected from monovalent C ₁ ～C ₂₀ Hydrocarbyl, divalent C ₁ ～C ₂₀ Hydrocarbyl or polyvalent C ₁ ～C ₂₀ A hydrocarbyl group. In some embodiments, the sheetValence of C ₁ ～C ₂₀ The hydrocarbon radical being selected from C ₁ ～C ₂₀ Alkyl (e.g. C) ₁ ～C ₆ Alkyl radical, C ₅ ～C ₈ Alkyl radical, C ₉ ～C ₁₂ Alkyl radical, C ₁₃ ～C ₁₆ Alkyl radical, C ₁₇ ～C ₂₀ Alkyl group), C ₆ ～C ₂₀ Aryl radical, C ₇ -C ₂₀ Alkylaryl and C ₇ -C ₂₀ An aralkyl group. In some embodiments, the divalent C ₁ ～C ₂₀ The hydrocarbon radical is selected from C ₁ ～C ₂₀ Alkylene (e.g. C) ₁ ～C ₆ Alkylene radical, C ₅ ～C ₈ Alkylene radical, C ₉ ～C ₁₂ Alkylene radical, C ₁₃ ～C ₁₆ Alkylene radical, C ₁₇ ～C ₂₀ Alkylene group), C ₆ ～C ₂₀ Arylene radical, C ₇ -C ₂₀ Alkarylene and C ₇ -C ₂₀ An aralkylene group. In some embodiments, the multivalent C ₁ ～C ₂₀ The hydrocarbon radical being selected from C ₁ ～C ₂₀ Trivalent alkyl (e.g. C) ₁ ～C ₆ Trivalent alkyl radical, C ₅ ～C ₈ Trivalent alkyl radical, C ₉ ～C ₁₂ Trivalent alkyl radical, C ₁₃ ～C ₁₆ Trivalent alkyl radical, C ₁₇ ～C ₂₀ Trivalent alkyl group), C ₆ ～C ₂₀ Trivalent aryl radical, C ₇ -C ₂₀ Trivalent alkaryl radical and C ₇ -C ₂₀ Trivalent aralkyl. In some embodiments, x is 1,2, 3, 4, or 5.

According to some embodiments of the invention, R ₁ ～R ₇ Each independently selected from C ₁ ～C ₁₀ A hydrocarbyl group. According to some embodiments of the invention, R ₁ ～R ₇ Each independently selected from C ₁ -C ₁₀ Alkyl radical, C ₃ -C ₁₀ Cycloalkyl radical, C ₆ -C ₁₀ Aryl radical, C ₇ -C ₁₀ Alkylaryl and C ₇ -C ₁₀ An aralkyl group.

According to some embodiments of the present invention, the isocyanate-based compound comprises one or more of 2, 4-toluene diisocyanate and its trimer, 2, 6-toluene diisocyanate and its trimer, tetramethylxylylene diisocyanate, trimethylhexamethylene diisocyanate, xylylene diisocyanate, methylcyclohexane diisocyanate, 1, 6-hexamethylene diisocyanate and its trimer, 4 '-diphenylmethane diisocyanate, 2,4' -diphenylmethane diisocyanate, 2 '-diphenylmethane diisocyanate, dicyclohexylmethane-4, 4' -diisocyanate, or lysine diisocyanate.

According to some embodiments of the invention, the diffusing agent comprises one or more of butyl ether, hexyl ether, tributyl citrate, dioctyl succinate, or dioctyl adipate.

According to some embodiments of the invention, the enhancer comprises one or more of stannous octoate, magnesium acetate, zinc acetate, magnesium laurate, dibutyl zinc or tetrabutyl tin.

According to some embodiments of the invention, the dispersing agent, molecular weight growth agent and accelerator comprise 0.1 to 2%, 0.5 to 5% and 5 × 10% of the mass of the polyester intermediate, respectively ^-4 ～15×10 ^-4 ％。

According to some embodiments of the invention, the magnesium-containing compound is 0.01 to 10 moles, for example, may be 0.05, 0.1, 0.3, 0.5, 0.7, 0.9, 1.5, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0 or any value in between, per mole of titanium-containing compound. In some embodiments, the magnesium-containing compound is present in an amount of from 0.2 to 5 moles, such as from 0.2 to 1 mole, per mole of titanium-containing compound.

In some embodiments, the zinc-containing compound is 0.01 to 10 moles, for example, can be 0.05 moles, 0.1 moles, 0.3 moles, 0.5 moles, 0.7 moles, 0.9 moles, 1.5 moles, 2.0 moles, 3.0 moles, 4.0 moles, 5.0 moles, 6.0 moles, 7.0 moles, 8.0 moles, 9.0 moles, or any value therebetween, per mole of titanium-containing compound. In some embodiments, the zinc-containing compound is present in an amount of from 0.1 to 5 moles, such as from 0.1 to 1 mole, per mole of titanium-containing compound.

In some embodiments, the hydroxyl containing compound is 1 to 20 moles, for example, may be 1.5 moles, 2.0 moles, 2.5 moles, 3.0 moles, 3.5 moles, 4.0 moles, 4.5 moles, 6.0 moles, 7.0 moles, 8.0 moles, 10.0 moles, 12.0 moles, 14.0 moles, 16.0 moles, 18.0 moles, or any value therebetween, per mole of titanium containing compound. In some embodiments, the hydroxyl containing compound is 1 to 10 moles, such as 1 to 5 moles, per mole of titanium containing compound.

In some embodiments, the carboxyl-containing compound is 0.01 to 0.5 moles per mole of the titanium-containing compound, for example, 0.05 moles, 0.07 moles, 0.09 moles, 0.15 moles, 0.20 moles, 0.25 moles, 0.30 moles, 0.35 moles, 0.40 moles, 0.45 moles, or any value therebetween. In some embodiments, the carboxyl-containing compound is present in an amount of from 0.1 to 0.5 moles per mole of titanium-containing compound.

In some embodiments, the epoxy-containing compound is 0.01 to 1 mole, for example, 0.05 mole, 0.07 mole, 0.09 mole, 0.15 mole, 0.20 mole, 0.25 mole, 0.30 mole, 0.35 mole, 0.40 mole, 0.45 mole, or any value therebetween, per mole of the titanium-containing compound. In some embodiments, the epoxy-containing compound is present in an amount of 0.1 to 0.5 moles per mole of titanium-containing compound.

In some embodiments, the concentration of the titanium element in the catalyst is 1 to 10wt%, such as 1.5wt%, 2.0wt%, 2.5wt%, 3.0wt%, 3.5wt%, 4.0wt%, 4.5wt%, 5.0wt%, 5.5wt%, 6.0wt%, 6.5wt%, 7.0wt%, 7.5wt%, 8.0wt%, 8.5wt%, 9.0wt%, 9.5wt%, or any value therebetween. In some embodiments, the concentration of titanium element in the catalyst is from 3 to 10wt%.

According to some embodiments of the invention, the titanium-containing compound is selected from the general formula Ti (OR) ¹ ) _m X _4-m One OR more of the compounds and titanium oxides shown, the general formula Ti (OR) ¹ ) _m X _4-m In (1),R ¹ is C ₂ -C ₁₀ A hydrocarbon group of (1); x is halogen, such as chlorine, bromine or iodine; m is an integer from 0 to 4, such as 0, 1,2, 3 or 4. In some embodiments, R ¹ Is C ₂ -C ₁₀ A hydrocarbon group of (1). In some embodiments, R ¹ Is C ₂ -C ₆ For example, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl or hexyl.

According to some embodiments of the invention, the titanium-containing compound is selected from one or more of titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, tetraethyl titanate, tetraisopropyl titanate, tetrabutyl titanate, and titanium dioxide.

According to some embodiments of the invention, the magnesium-containing compound is selected from the general formula Mg (OR) ² ) ₂ X _2-n A compound of the formula and the general formula Mg (OOR) ³ ) ₂ One OR more of the compounds shown in the general formula Mg (OR) ² ) ₂ X _2-n In, R ² Is C ₂ -C ₁₀ X is halogen, such as chlorine, bromine or iodine; n is an integer from 0 to 2, such as 0, 1 or 2; the general formula Mg (OOR) ³ ) ₂ In, R ³ Is C ₂ -C ₁₀ A hydrocarbon group of (2). In some embodiments, R ² Is C ₂ -C ₆ For example ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl or hexyl. In some embodiments, R ³ Is C ₂ -C ₆ For example ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl or hexyl.

According to some embodiments of the invention, the magnesium-containing compound is selected from one or more of magnesium dichloride, magnesium dibromide, magnesium diiodide, diethoxymagnesium, dipropoxymagnesium, diisopropoxymagnesium, dibutoxymagnesium, diisobutyoxymagnesium, magnesium acetate, magnesium propionate and magnesium butyrate.

According to some embodiments of the invention, the zinc-containing compound is selected from the general formula Zn (OOR) ⁴ ) ₂ Shown inOne or more of a compound and a zinc halide, said general formula Zn (OOR) ⁴ ) ₂ In, R ⁴ Is C ₂ -C ₂₀ A hydrocarbon group of (1). In some embodiments, R ⁴ Is C ₂ -C ₁₀ A hydrocarbon group of (1). In some embodiments, R ⁴ Is C ₂ -C ₆ For example ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl or hexyl.

According to some embodiments of the invention, the zinc-containing compound is selected from one or more of zinc dichloride, zinc dibromide, zinc diiodide, zinc acetate, zinc propionate, zinc butyrate and zinc stearate.

According to some embodiments of the invention, the hydroxyl containing compound is selected from one or more of a monohydric alcohol and a polyhydric alcohol. In some embodiments, the monohydric alcohol is C ₁ -C ₁₀ A monohydric alcohol of (2). In some embodiments, the polyol is a 2-6-membered alcohol, e.g., C ₂ -C ₁₀ Diol of (2), C ₃ -C ₁₅ Trihydric alcohol of (1), C ₄ -C ₂₀ Tetrahydric alcohol of (1), C ₅ -C ₂₀ Pentahydric alcohol or C of ₆ -C ₂₀ The hexahydric alcohol of (2).

According to some embodiments of the invention, the hydroxyl containing compound is selected from one or more of methanol, ethanol, isopropanol, n-butanol, n-pentanol, 2-pentanol, 3-pentanol, ethylene glycol, 1, 3-propanediol, 1, 4-butanediol, 1, 5-pentanediol, pentaerythritol, and sorbitol.

According to some embodiments of the invention, the carboxyl-containing compound is selected from one or more of a monocarboxylic acid and a polycarboxylic acid. In some embodiments, the monocarboxylic acid is C ₁ -C ₂₀ A monocarboxylic acid of (2). In some embodiments the polycarboxylic acid is C ₂ -C ₂₀ Of dicarboxylic acids or C ₃ -C ₂₀ The tricarboxylic acid of (1).

According to some embodiments of the present invention, the carboxyl-group-containing compound is at least one selected from the group consisting of formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, stearic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, and adipic acid.

According to some embodiments of the invention, the epoxy-containing compound is selected from the group consisting of

One or more of the compounds shown in the general formula

In, R ⁵ And R ⁶ The same or different, each independently selected from hydrogen or C1-C20 hydrocarbyl. In some embodiments, R ⁵ And R ⁶ Each independently selected from hydrogen or C1-C10 hydrocarbyl. In some embodiments, R ⁵ And R ⁶ Each independently selected from hydrogen or C1-C10 alkyl, e.g., C1-C6 alkyl. In some embodiments, R ⁵ And R ⁶ Each independently selected from hydrogen, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl or hexyl.

According to some embodiments of the invention, the epoxy-containing compound is selected from one or more of ethylene oxide, propylene oxide, 1, 2-butylene oxide, 1, 4-butylene oxide or 1, 2-pentylene oxide.

According to some embodiments of the invention, the method of preparing the first catalyst comprises the steps of:

step A: reacting a portion of the hydroxyl-containing compound with the carboxyl-containing compound to obtain a first solution;

and B: adding the rest of hydroxyl-containing compound, magnesium-containing compound, zinc-containing compound and titanium-containing compound into the first solution, and reacting to obtain a second solution.

According to some embodiments of the invention, the method further comprises step C: standing and curing the second solution.

According to some embodiments of the invention, in step a, the reaction temperature is 60-200 ℃, such as 70 ℃,90 ℃, 100 ℃,110 ℃, 130 ℃, 150 ℃, 170 ℃, 190 ℃ or any value in between. In some embodiments, in step a, the reaction time is 0.5 to 5h, for example 1h, 2h, 3h or 4h. According to some embodiments of the invention, in step B, the reaction temperature is 40-100 ℃, such as 50 ℃,60 ℃, 70 ℃, 80 ℃,90 ℃ or any value in between. In some embodiments, the reaction time in step B is 0.5 to 5h, for example 1h, 2h, 3h or 4h. According to some embodiments of the invention, the curing temperature is 20-60 ℃, such as 25 ℃, 30 ℃, 35 ℃,40 ℃, 45 ℃,50 ℃, 55 ℃ or any value in between. According to some embodiments of the invention, in step C, the maturation time is 5-24, for example 7h, 9h, 10h, 13h, 15h, 17h, 19h, 20h or 22h.

The first catalyst is compounded by a magnesium-containing compound, a zinc-containing compound and a titanium-containing compound, and a product obtained by reacting a hydroxyl-containing compound and a carboxyl-containing compound is dispersed to ensure the catalytic activity and selectivity of the catalyst. The first catalyst has the advantages of simple preparation process, mild preparation conditions and low cost of raw materials.

According to some embodiments of the invention, the method of preparing the second catalyst comprises the steps of:

step M: reacting a hydroxyl-containing compound, an epoxy-containing compound and one selected from a zinc-containing compound and a magnesium-containing compound to obtain a third solution;

and step N: adding another selected from a zinc-containing compound and a magnesium-containing compound, a titanium-containing compound and an optional hydroxyl-containing compound into the third solution of the step M, and reacting to obtain a fourth solution.

According to some embodiments of the invention, the method of preparing comprises the steps of:

step M1: reacting a hydroxyl-containing compound, an epoxy-containing compound and a zinc-containing compound to obtain a third solution,

step N1: and (3) adding a magnesium-containing compound, a titanium-containing compound and an optional hydroxyl-containing compound into the third solution in the step M1, and reacting to obtain a fourth solution.

step M1: reacting part of the hydroxyl-containing compound, the epoxy-containing compound and the zinc-containing compound to obtain a third solution, preferably, step M1 comprises mixing part of the hydroxyl-containing compound and the epoxy-containing compound to obtain a first mixture, reacting the first mixture with the zinc-containing compound to obtain the third solution, more preferably, the temperature of the mixing is 30 to 80 ℃, for example, 30 ℃,40 ℃,50 ℃,60 ℃, 70 ℃, 80 ℃ or any value therebetween. In some embodiments, the time of mixing is 0.5 to 5 hours, for example 1 hour, 2 hours, 3 hours, or 4 hours;

step N1: and (3) adding a magnesium-containing compound, a titanium-containing compound and the rest hydroxyl-containing compound into the third solution obtained in the step M1, and reacting to obtain a fourth solution.

step M1: reacting a hydroxyl-containing compound, an epoxy-containing compound and a zinc-containing compound to obtain a third solution, preferably step M1 comprises mixing a hydroxyl-containing compound and an epoxy-containing compound to obtain a first mixture, reacting the first mixture with a zinc-containing compound to obtain a third solution, more preferably the temperature of the mixing is 30 to 80 ℃, such as 30 ℃,40 ℃,50 ℃,60 ℃, 70 ℃, 80 ℃ or any value therebetween. In some embodiments, the time of mixing is 0.5 to 5 hours, for example 1 hour, 2 hours, 3 hours, or 4 hours;

step N1: and (3) adding a magnesium-containing compound and a titanium-containing compound into the first solution obtained in the step M1, and reacting to obtain a fourth solution.

step M2: reacting a hydroxyl-containing compound, an epoxy-containing compound and a magnesium-containing compound to obtain a third solution,

and step N2: adding a zinc-containing compound, a titanium-containing compound and an optional hydroxyl-containing compound into the third solution obtained in the step M2, and reacting to obtain a fourth solution.

step M2: reacting a portion of the hydroxyl-containing compound, the epoxy-containing compound, and the magnesium-containing compound to obtain a third solution, preferably, step M2 comprises mixing a portion of the hydroxyl-containing compound and the epoxy-containing compound to obtain a first mixture, and reacting the first mixture with the magnesium-containing compound to obtain the third solution, more preferably, the temperature of the mixing is 30 to 80 ℃, such as 30 ℃,40 ℃,50 ℃,60 ℃, 70 ℃, 80 ℃, or any value therebetween. In some embodiments, the time of mixing is 0.5 to 5 hours, for example 1 hour, 2 hours, 3 hours, or 4 hours;

and step N2: and (3) adding the zinc-containing compound, the titanium-containing compound and the rest of the hydroxyl-containing compound into the third solution obtained in the step M2, and reacting to obtain a fourth solution.

step M2: reacting the hydroxyl-containing compound, the epoxy-containing compound and the magnesium-containing compound to obtain a third solution, preferably step M2 comprises mixing the hydroxyl-containing compound and the epoxy-containing compound to obtain a first mixture, reacting the first mixture with the magnesium-containing compound to obtain the third solution, more preferably the temperature of the mixing is 30 to 80 ℃, such as 30 ℃,40 ℃,50 ℃,60 ℃, 70 ℃, 80 ℃ or any value in between. In some embodiments, the time of mixing is 0.5 to 5 hours, for example 1 hour, 2 hours, 3 hours, or 4 hours;

and step N2: and (3) adding a zinc-containing compound and a titanium-containing compound into the first solution obtained in the step M2, and reacting to obtain a fourth solution.

According to some embodiments of the invention, the method further comprises step O: standing and curing the second solution.

According to some implementations of the invention, in steps M, M1, M2, the reaction temperature ranges from 0 to 100 ℃, such as 10 ℃, 20 ℃, 30 ℃,40 ℃,50 ℃,60 ℃, 70 ℃, 80 ℃,90 ℃ or any value in between. In some embodiments, the reaction time in steps M, M1, M2 is 0.5 to 5h, for example 1h, 2h, 3h or 4h. In some embodiments, the reaction temperature in steps N, N1, N2 is 25-100 ℃, such as 30 ℃,40 ℃,50 ℃,60 ℃, 70 ℃, 80 ℃,90 ℃ or any value in between. In some embodiments, the reaction time in steps N, N1, N2 is 0.5 to 5h, for example 1h, 2h, 3h or 4h. In some embodiments, in step O, the curing temperature is 20 to 60 ℃, such as 25 ℃, 30 ℃, 35 ℃,40 ℃, 45 ℃,50 ℃, 55 ℃ or any value O therebetween. In some embodiments, in step O, the maturation time is 5-24h, for example 7h, 9h, 10h, 13h, 15h, 17h, 19h, 20h or 22h.

The second catalyst of the invention disperses and complexes the magnesium-containing compound, the zinc-containing compound and the titanium compound through a product obtained by the reaction of the hydroxyl-containing compound and the epoxy-containing compound, thereby regulating and controlling the catalytic activity and selectivity of the titanium catalyst. The method has the advantages of simple process, mild preparation conditions and low cost of raw materials.

According to some embodiments of the invention, the aliphatic dibasic acid is C ₂ ～C ₁₆ Dibasic acid of (1), C ₂ ～C ₁₆ Aliphatic dibasic acid anhydride or C ₂ ～C ₁₆ One or more of the aliphatic dicarboxylic acid halides of (a). According to some embodiments of the invention, the aliphatic dibasic acid is C ₂ ～C ₁₀ Dibasic acid of (1), C ₂ ～C ₁₀ Aliphatic dicarboxylic anhydrides or C ₂ ～C ₁₀ One or more of the aliphatic dicarboxylic acid halides of (a). In some embodiments of the invention, the aliphatic dibasic acid comprises one or more of succinic acid, glutaric acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, 1, 4-cyclohexanedicarboxylic acid, glutaric anhydride or malonyl chloride.

According to some embodiments of the invention, the aromatic dibasic acid is selected from C ₈ ～C ₁₆ Aromatic dibasic acid of (2), C ₈ ～C ₁₆ Or C is an aromatic dicarboxylic anhydride ₈ ～C ₁₆ One or more of aromatic dicarboxylic acid halides. In some embodiments of the present invention, the first and second electrodes are, the aromatic dibasic acid comprises terephthalic acid, terephthalic anhydride, terephthalic acyl halide isophthalic acid, isophthalic anhydride, isophthaloyl halide, naphthalenedicarboxylic acid, naphthalenedicarboxylic anhydride,One or more of naphthaloyl halides.

According to some embodiments of the invention, the aliphatic diol is selected from C ₂ ～C ₁₀ One or more of the aliphatic diols (b). According to some embodiments of the invention, the aliphatic diol is C ₂ ～C ₆ One or more of the aliphatic diols (b). In some embodiments of the invention, the aliphatic diol comprises one or more of ethylene glycol, 1, 2-propylene glycol, 1, 3-propylene glycol, 1, 4-butanediol, 1, 5-pentanediol, neopentyl glycol, 1, 6-hexanediol, or a polyether diol.

According to some embodiments of the present invention, the molar content of hydroxyl functional groups to the molar content of total carboxylic acid, anhydride, and acid halide functional groups in the aliphatic dibasic acid, aromatic dibasic acid, and aliphatic diol is (1.2 to 2.5): 1.

according to some embodiments of the invention, in step S1, the esterification reaction temperature is 150 ℃ to 250 ℃, the absolute pressure is 40KPa to 110KPa, and the reaction time is 2h to 6h. According to some embodiments of the invention, the temperature of the esterification reaction is 150 ℃, 170 ℃, 190 ℃, 210 ℃, 230 ℃, 250 ℃ and any value in between. According to some embodiments of the invention, the absolute pressure of the esterification reaction is 40KPa, 60KPa, 80KPa, 100KPa, 110KPa, and any value therebetween. According to some embodiments of the invention, the esterification reaction time is 2h, 3h, 4h, 5h, 6h and any value in between.

According to some embodiments of the invention, in step S2, the polycondensation reaction comprises a first polycondensation reaction and a second polycondensation reaction performed in sequence. According to some embodiments of the invention, the first polycondensation reaction is carried out at a temperature of 220 ℃ to 250 ℃, an absolute pressure of 1KPa to 5KPa, and a reaction time of 1h to 3h. According to some embodiments of the invention, the second polycondensation reaction is carried out at a temperature of 220 ℃ to 250 ℃, an absolute pressure of 10Pa to 300Pa, and a reaction time of 1h to 3h. According to some embodiments of the invention, the temperature of the first and/or second polycondensation reaction is 220 ℃, 230 ℃, 240 ℃, 250 ℃ and any value in between. According to some embodiments of the invention, the absolute pressure of the first polycondensation reaction is 1.5KPa, 2KPa, 2.5KPa, 3KPa, 4KPa, and any value therebetween. According to some embodiments of the invention, the absolute pressure of the second polycondensation reaction is 50Pa, 100Pa, 150Pa, 200Pa, 250Pa, and any value therebetween. According to some embodiments of the invention, the time of the first and/or second polycondensation reaction is 1.5h, 2h, 2.5h, and any value therebetween.

According to some embodiments of the invention, in step S3, the temperature of the chain extension reaction is 25 ℃ to 100 ℃ for 4h to 24h. According to some embodiments of the invention, the temperature of the chain extension reaction is 25 ℃, 35 ℃, 45 ℃, 55 ℃, 65 ℃, 75 ℃, 85 ℃, 95 ℃, 100 ℃ and any value in between. According to some embodiments of the invention, the chain extension reaction time is 4h, 8h, 12h, 16h, 20h, 24h and any value in between.

According to some embodiments of the present invention, in step S1, the esterification reaction products are mixed, wherein the esterification rate of the esterification reaction products is greater than or equal to 98%.

According to some embodiments of the invention, step S2 further comprises, after the polycondensation reaction, pelletizing and drying to obtain the polyester intermediate. According to some embodiments of the invention, the intrinsic viscosity of the polyester intermediate is between 0.2 and 1.2dl/g.

(1) Esterification reaction, namely respectively carrying out esterification reaction on aliphatic dibasic acid and aromatic dibasic acid with aliphatic dibasic alcohol in the presence of a first catalyst and/or a second catalyst in an esterification unit under the conditions of high temperature and proper pressure, and fully mixing after the esterification rate reaches 98% to obtain an esterified substance Z;

(2) Performing polycondensation reaction, namely removing small molecules such as water, excessive dihydric alcohol and the like from the esterified substance Z in a polycondensation unit under the absolute pressure of 1KPa to 5KPa and the absolute pressure of 10Pa to 300Pa in sequence, and granulating and drying to obtain a polyester intermediate M;

(3) And (3) performing chain growth reaction, namely, fully mixing the polyester intermediate M and the auxiliary agent in a mixer, and performing chain growth reaction at low temperature to prepare the aliphatic-aromatic copolyester product P.

The inventor of the invention discovers that in the process of researching the polymerization of the biodegradable aliphatic-aromatic copolyester, the polycondensation of the polyester is an equilibrium reaction, the chain growth, the chain breakage and the chain transfer reaction are simultaneously carried out, when the three reactions reach equilibrium, the polyester has certain viscosity and lower carboxyl end group, the polycondensation reaction is terminated, and the chain growth reaction is carried out under the mild condition of low temperature, so that the polyester product with low carboxyl end group, less gel point and high molecular weight can be prepared.

The second aspect of the present invention provides an aliphatic-aromatic copolyester obtained according to the preparation method of the first aspect.

According to some embodiments of the invention, the aliphatic-aromatic copolyester has an intrinsic viscosity of 1.6 to 1.8dl/g.

According to some embodiments of the invention, the aliphatic-aromatic copolyester has a content of terminal carboxyl groups of less than or equal to 25mmol/kg, preferably less than or equal to 15mmol/kg.

According to some embodiments of the invention, the aliphatic-aromatic copolyester has a gel point of 35 or less/m ² Preferably 10 or less per m ² 。

According to some embodiments of the invention, the aliphatic-aromatic copolyester has a mass average molecular weight of 6.7 × 10 ⁴ ～14.7×10 ⁴ Preferably 10.1X 10 ⁴ ～14.7×10 ⁴ 。

According to some embodiments of the invention, the aliphatic-aromatic copolyester has a molecular weight distribution of 1.8 to 2.6, preferably 1.8 to 2.1.

A third aspect of the invention provides the use of an aliphatic-aromatic copolyester according to the second aspect in a polyester film material or a polyester sheet material.

The invention has the following beneficial effects:

(1) The preparation method of the aliphatic-aromatic copolyester has simple process, and eliminates a double-shaft reactor or a dynamic mixer liquid phase viscosity-increasing high-energy consumption device;

(2) The aliphatic-aromatic copolyester product prepared by the preparation method has high stability and excellent product quality, and can realize that the carboxyl end groups of the copolyester resin are less than or equal to 25mmol/kg and even less than or equal to 15mmol/kg, and the gel point is less than or equal to 35/m ² Even less than or equal to 10/m ² Mass average molecular weight of 6.7X 10 ⁴ ～14.7×10 ⁴ The molecular weight distribution is narrow and is 1.8-2.6.

Detailed Description

The present invention will be further illustrated by the following specific examples, but the scope of the present invention is not limited thereto.

The polymer was tested for carboxyl end groups by acid-base titration, the test being carried out according to the method specified in GB/T32366-2015. The mixed solution is selected from phenol-chloroform, and the volume ratio is 2. The standard titration solution is potassium hydroxide-benzyl alcohol, the concentration is 0.01mol/L, and the standard titration solution is configured and calibrated according to 4.24 in GB/T601-2002. Bromophenol blue indicator concentration was 0.2%. Test preparation: 0.5g of the sample was dissolved in 25.00ml of a phenol-chloroform mixed solvent.

Testing the gel point of a polyester sample film/sheet by projection, wherein the test comprises 4 films/sheets, and each film has a size of at least 200mm ² At 254mm ² Is excellent in size>Counting statistics is carried out on gel points of 0.6mm or between 0.3 mm and 0.6mm respectively.

The molecular weight and the molecular weight distribution of the polymer are determined by adopting a gel permeation chromatography method, chloroform is used as a solvent, a Waters-e2695 instrument is used for testing, and polystyrene is used as a standard sample.

Examples of preparation of catalysts

Preparation example 1

54.9g of 1, 4-butanediol and 3.4g of acetic acid are sequentially added into a reactor, and the mixture is heated for 0.5h at the temperature of 90 ℃ to obtain a transparent solution A1; then, 10.1g of butanol, 5.2g of ethanol, 5.2g of magnesium bromide, 7.9g of zinc bromide and 26.9g of titanium tetrachloride are sequentially added, the mixture is uniformly stirred and heated for 2 hours at the temperature of 60 ℃ to obtain a transparent solution B1, and the transparent solution B1 is kept stand and cured for 12 hours at the temperature of 50 ℃ to obtain a catalyst solution C1.

Preparation example 2

Adding 36.0g of ethylene glycol and 8.2g of adipic acid into a reactor, and heating at 110 ℃ for 1h to obtain a transparent solution A2; then sequentially adding 10.1g of propanol, 5.2g of ethanol, 9.3g of magnesium butoxide, 4.8g of zinc chloride and 11.6g of titanium dioxide, stirring uniformly, and heating for 3 hours at 90 ℃ to obtain a solution B2; standing and curing for 20h at the temperature of 40 ℃ to obtain a catalyst solution C2.

Preparation example 3

Adding 32.7g of 1, 3-propylene glycol and 16.0g of stearic acid into a reactor, and heating for 2 hours at 180 ℃ to obtain a transparent solution A3; then sequentially adding 10.2g of sorbitol, 7.8g of magnesium acetate, 11.2g of zinc iodide and 41.1g of tetraisopropyl titanate, uniformly stirring, and heating for 4 hours at the temperature of 80 ℃ to obtain a transparent solution B3; standing and curing for 24 hours at the temperature of 25 ℃ to obtain a catalyst solution C3.

Preparation example 4

Adding 31.6g of 1, 5-pentanediol and 7.2g of succinic acid into a reactor, and heating at 135 ℃ for 1h to obtain a transparent solution A4; then adding 10.1g of pentaerythritol, 5.2g of ethanol, 7.8g of magnesium acetate, 7.9g of zinc acetate and 49.2g of tetrabutyl titanate in turn, uniformly stirring, and heating for 3 hours at 70 ℃ to obtain a transparent solution B4; standing and curing for 20h at the temperature of 30 ℃ to obtain a catalyst solution C4.

Preparation example 5

Adding 62.8g of 1, 4-butanediol and 3.4g of acetic acid into a reactor in sequence, heating for 0.5h at the temperature of 90 ℃ to obtain a transparent solution A5; then 10.1g of butanol, 5.2g of ethanol, 26.9g of titanium tetrachloride and 5.2g of magnesium bromide are sequentially added, the mixture is uniformly stirred and heated for 2 hours at the temperature of 60 ℃ to obtain a transparent solution B5, and the transparent solution B5 is kept stand and cured for 12 hours at the temperature of 50 ℃ to obtain a catalyst solution C5.

Preparation example 6

60.1g of 1, 4-butanediol and 3.4g of acetic acid are sequentially added into a reactor, and the mixture is heated for 0.5h at the temperature of 90 ℃ to obtain a transparent solution A6; then 10.1g of butanol, 5.2g of ethanol, 26.9g of titanium tetrachloride and 7.9g of zinc bromide are sequentially added, the mixture is uniformly stirred and heated for 2 hours at the temperature of 60 ℃ to obtain a transparent solution B6, and the transparent solution B6 is kept stand and cured for 12 hours at the temperature of 50 ℃ to obtain a catalyst solution C6.

Preparation example 7

58.3g of 1, 4-butanediol is sequentially added into a reactor, after heating for 0.5h at 90 ℃, 10.1g of butanol, 5.2g of ethanol, 26.9g of titanium tetrachloride, 5.2g of magnesium bromide and 7.9g of zinc bromide are sequentially added, stirring uniformly and heating for 2h at 60 ℃ is carried out to obtain a transparent solution B7, and standing and curing are carried out for 12h at 50 ℃ to obtain a catalyst solution C7.

Preparation example 8

Adding 57.3g of 1, 4-butanediol and 6.4g of zinc acetate into a reactor in sequence, heating and stirring for 4 hours at the temperature of 60 ℃, then slowly adding 2.5g of ethylene oxide, and reacting for 4 hours at the temperature of 10 ℃ to obtain a solution A8; then 10.1g of butanol, 5.2g of ethanol, 5.2g of magnesium bromide and 26.9g of titanium tetrachloride are sequentially added, the mixture is uniformly stirred and heated at 60 ℃ for reaction for 2 hours to obtain a solution B8, and the solution B8 is kept stand and cured at 25 ℃ for 24 hours to obtain a catalyst solution C8.

Preparation example 9

Adding 48.1g of ethylene glycol and 7.4g of zinc propionate into a reactor in sequence, heating and stirring for 4 hours at 60 ℃, slowly adding 3.3g of propylene oxide, and reacting for 1 hour at 40 ℃ to obtain a solution A9; sequentially adding 8.2g of propanol, 5.2g of ethanol, 9.3g of butanol magnesium and 26.9g of titanium tetrachloride, uniformly stirring, heating at 60 ℃ for reacting for 2 hours to obtain a solution B9; standing and curing for 20h at 40 ℃ to obtain a catalyst solution C9.

Preparation example 10

Adding 34.2g of 1, 3-propylene glycol and 22.0g of zinc stearate into a reactor in sequence, heating and stirring for 4 hours at the temperature of 60 ℃, then slowly adding 4.1g of epoxy butane, and reacting for 1 hour at the temperature of 50 ℃ to obtain a solution A10; then, adding 8.2g of amyl alcohol, 5.2g of ethanol, 7.8g of magnesium acetate and 26.9g of titanium tetrachloride in sequence, uniformly stirring, heating at 60 ℃ for reacting for 2 hours to obtain a solution B10; standing and curing for 20h at 50 ℃ to obtain a catalyst solution C10.

Preparation example 11

Adding 61.7g of 1, 4-butanediol and 5.9g of zinc chloride into a reactor, heating and stirring for 4 hours at the temperature of 60 ℃, then slowly adding 2.5g of ethylene oxide, and reacting for 4 hours at the temperature of 10 ℃ to obtain a solution A11; then adding 7.8g of magnesium acetate and 41.09g of tetraisopropyl titanate in sequence, stirring uniformly, heating at 80 ℃ for reacting for 2h to obtain a solution B11; standing and curing for 24 hours at 25 ℃ to obtain a catalyst solution C11.

Preparation example 12

Sequentially adding 62.5g of 1, 4-butanediol and 6.4g of zinc acetate into a reactor, heating and stirring for 4 hours at 60 ℃, then slowly adding 2.5g of ethylene oxide, and reacting for 4 hours at 10 ℃ to obtain a solution A12; then 10.1g of butanol, 5.2g of ethanol and 26.9g of titanium tetrachloride are added in sequence, the mixture is stirred evenly at 60 ℃ and heated for 2 hours to react to obtain a solution B12, and the solution B12 is kept stand and cured at 25 ℃ for 24 hours to obtain a catalyst solution C12.

Preparation example 13

59.8g of 1, 4-butanediol and 6.4g of zinc acetate are sequentially added into a reactor, heated and stirred at 60 ℃ for 4h, and reacted at 10 ℃ for 4h to obtain a solution A13; then 10.1g of butanol, 5.2g of ethanol, 5.2g of magnesium bromide and 26.9g of titanium tetrachloride are sequentially added, the mixture is stirred uniformly at 60 ℃ and is heated for 2 hours to react to obtain a solution B13, and the solution B13 is kept stand and cured at 25 ℃ for 24 hours to obtain a catalyst solution C13.

Preparation example 14

Adding 63.7g of 1, 4-butanediol into the reactor, slowly adding 2.5g of ethylene oxide, and reacting at 10 ℃ for 4 hours to obtain a solution A14; then 10.1g of butanol, 5.2g of ethanol, 5.2g of magnesium bromide and 26.9g of titanium tetrachloride are sequentially added, the mixture is stirred uniformly at 60 ℃ and heated for 2 hours to react to obtain a solution B14, and the solution B14 is kept stand at 25 ℃ for aging for 24 hours to obtain a catalyst solution C14.

Examples

Example 1

126.0kg/h of 2, 6-naphthalenedicarboxylic acid, 65.0kg/h of 1, 3-propanediol and 10.25 kg/h of catalyst solution are stirred and mixed in proportion and enter an esterification unit for esterification reaction, the temperature of reaction materials is 210 ℃, and the absolute pressure is 90KPa; mixing 90.5kg/h of adipic acid, 56.5kg/h of 1, 3-propylene glycol and 10.25 kg/h of catalyst solution C, stirring, and allowing the mixture to enter an esterification unit for esterification reaction, wherein the temperature of a reaction material is 180 ℃, the absolute pressure is 90KPa, and when the two groups of esterification rates reach 98%, fully mixing to obtain an esterified substance Z1;

the esterification product Z1 enters a polycondensation unit, the reaction temperature is 210 ℃, the absolute pressure is 4KPa, the reaction time is 2 hours, the absolute pressure is adjusted to 150Pa, the reaction temperature is 210 ℃, the reaction time is 2 hours, and a polyester intermediate M1 is obtained through granulation and drying;

the polyester resin intermediate M1 264.6kg/h, butyl ether 0.8kg/h, 2, 4-diphenylmethane diisocyanate 7.9kg/h, stannous octoate 2.6g/h continuously enter a static mixer for mixing and diffusion, and a chain growth reaction is carried out at the temperature of 60 ℃, and the polyester product P1 is obtained after 4h.

Example 2

Only different from example 1 in that butyl ether was replaced by hexyl ether, a polyester product P2 was prepared.

Example 3

The only difference from example 1 is that polyester product P3 was prepared by replacing 2, 4-diphenylmethane diisocyanate with dicyclohexylmethane-4, 4' -diisocyanate.

Example 4

The only difference from example 1 was that the polyester product P4 was prepared by replacing stannous octoate with magnesium laurate.

Example 5

Stirring and mixing 96.8kg/h of terephthalic acid, 89.1kg/h of 1, 5-pentanediol and 0.27kg/h of catalyst solution C, and feeding the mixture into an esterification unit for esterification reaction, wherein the temperature of a reaction material is 240 ℃, and the absolute pressure is 80KPa; 125.2kg/h of sebacic acid, 77.4kg/h of 1, 5-pentanediol and 0.27kg/h of catalyst solution C are stirred and mixed in proportion, the mixture enters an esterification unit for esterification reaction, the temperature of reaction materials is 240 ℃, the absolute pressure is 80KPa, and when the esterification rate of two groups reaches 98%, the two groups are fully mixed to obtain an esterified substance Z5;

the esterification product Z5 enters a polycondensation unit, the reaction temperature is 240 ℃, the absolute pressure is 2KPa, the reaction time is 1h, the absolute pressure is adjusted to 100Pa, the reaction temperature is 240 ℃, the reaction time is 1h, and a polyester intermediate M5 is obtained through pelletizing and drying;

the polyester intermediate M5303.9 kg/h, tributyl citrate 1.2kg/h, 2, 6-toluene diisocyanate 2.4kg/h, magnesium acetate 3.6g/h continuously enter a static mixer to be mixed and undergo a chain extension reaction at 70 ℃, and a polyester product P5 is obtained after 6h.

Example 6

The only difference from example 5 is that polyester product P6 was prepared by replacing tributyl citrate with dioctyl adipate.

Example 7

Stirring and mixing 96.8kg/h of terephthalic acid, 78.8kg/h of 1, 4-butanediol and 0.26kg/h of catalyst solution C, and feeding the mixture into an esterification unit for esterification reaction, wherein the temperature of a reaction material is 240 ℃ and the absolute pressure is 75KPa; 92.2kg/h of adipic acid, 85.2kg/h of 1, 4-butanediol and 0.25kg/h of catalyst solution C are stirred and mixed in proportion, the mixture enters an esterification unit for esterification reaction, the temperature of reaction materials is 190 ℃, the absolute pressure is 70KPa, and the esterification products are fully mixed to obtain an esterified product Z7 when the esterification rates of the two groups reach 98%;

the esterification product Z7 enters a polycondensation unit, the reaction temperature is 230 ℃, the absolute pressure is 3KPa, the reaction time is 1h, the absolute pressure is adjusted to 200Pa, the reaction temperature is 230 ℃, the reaction time is 3h, and a polyester intermediate M7 is obtained through pelletizing and drying;

polyester intermediate M7267.3 kg/h, dioctyl adipate 1.0kg/h, dicyclohexylmethane-4, 4' -diisocyanate 2.7kg/h, tetrabutyltin 1.4g/h continuously enter a static mixer to be mixed, a chain extension reaction is carried out at 50 ℃, and a polyester product P7 is obtained after 8 h.

Example 8

Only in difference to example 7 was the substitution of tetrabutyltin for dibutylzinc, a polyester product P8 was prepared.

Example 9

126.0kg/h of 2, 6-naphthalenedicarboxylic acid, 65.0kg/h of 1, 3-propanediol and 40.25 kg/h of catalyst solution are stirred and mixed in proportion and enter an esterification unit for esterification reaction, the temperature of reaction materials is 210 ℃, and the absolute pressure is 90KPa; mixing 90.5kg/h of adipic acid, 56.5kg/h of 1, 3-propylene glycol and 0.25kg/h of catalyst solution C, stirring, and allowing the mixture to enter an esterification unit for esterification reaction, wherein the temperature of reaction materials is 180 ℃, the absolute pressure is 90KPa, and when the esterification rates of two groups reach 98%, the two groups are fully mixed to obtain an esterified substance Z9;

the esterification product Z9 enters a polycondensation unit, the reaction temperature is 210 ℃, the absolute pressure is 4KPa, the reaction time is 2 hours, the absolute pressure is adjusted to 150Pa, the reaction temperature is 210 ℃, the reaction time is 2 hours, and a polyester intermediate M9 is obtained through granulation and drying;

the polyester resin intermediate M9264.6 kg/h, 2, 4-diphenylmethane diisocyanate 7.9kg/h and stannous octoate 2.6g/h continuously enter a static mixer for mixing and diffusion, the chain growth reaction is carried out at the temperature of 60 ℃, and the polyester product P9 is obtained after 4h.

Example 10

Stirring and mixing 96.8kg/h of terephthalic acid, 89.1kg/h of 1, 5-pentanediol and 0.27kg/h of catalyst solution C, and feeding the mixture into an esterification unit for esterification reaction, wherein the temperature of reaction materials is 240 ℃ and the absolute pressure is 80KPa; 125.2kg/h sebacic acid, 77.4kg/h 1, 5-pentanediol and 0.27kg/h catalyst solution C are stirred and mixed in proportion, the mixture enters an esterification unit for esterification reaction, the temperature of a reaction material is 240 ℃, the absolute pressure is 80KPa, and when the esterification rate of two groups reaches 98%, the two groups are fully mixed to obtain an esterified substance Z10;

the esterification product Z10 enters a polycondensation unit, the reaction temperature is 240 ℃, the absolute pressure is 2KPa, the reaction time is 1h, the absolute pressure is adjusted to 100Pa, the reaction temperature is 240 ℃, the reaction time is 1h, and a polyester intermediate M10 is obtained through granulation and drying;

the polyester intermediate M10303.9 kg/h, tributyl citrate 1.2kg/h and 2.4kg/h of 2, 6-toluene diisocyanate continuously enter a static mixer to be mixed, chain growth reaction is carried out at 70 ℃, and a polyester product P10 is obtained after 6h.

Example 11

Stirring and mixing 96.8kg/h of terephthalic acid, 78.8kg/h of 1, 4-butanediol and 0.26kg/h of catalyst solution C, and feeding the mixture into an esterification unit for esterification reaction, wherein the temperature of a reaction material is 240 ℃ and the absolute pressure is 75KPa; 92.2kg/h of adipic acid, 85.2kg/h of 1, 4-butanediol and 0.25kg/h of catalyst solution C are stirred and mixed in proportion, the mixture enters an esterification unit for esterification reaction, the temperature of a reaction material is 190 ℃, the absolute pressure is 70KPa, and when the esterification rates of two groups reach 98%, the two groups are fully mixed to obtain an esterified substance Z11;

the esterification product Z11 enters a polycondensation unit, the reaction temperature is 230 ℃, the absolute pressure is 3KPa, the reaction time is 1h, the absolute pressure is adjusted to 200Pa, the reaction temperature is 230 ℃, the reaction time is 3h, and a polyester intermediate M11 is obtained through granulation and drying;

the polyester intermediate M11267.3 kg/h and dicyclohexylmethane-4, 4' -diisocyanate 2.7kg/h continuously enter a static mixer to be mixed, and a chain growth reaction is carried out at the temperature of 50 ℃ for 8h to obtain a polyester product P11.

Examples 12 to 14

The only difference from example 1 is that polyester products P12 to P14 were prepared by replacing the catalysts with catalyst solutions C2 to C4, respectively.

Comparative examples 1 to 3

The only difference from example 1 is that polyester products P15 to P17 were prepared by replacing the catalyst with catalyst solutions C5 to C7, respectively.

Examples 15 to 18

The only difference from example 1 is that polyester products P18 to P21 were prepared by replacing the catalysts with catalyst solutions C8 to C11, respectively.

Comparative examples 4 to 6

The only difference from example 1 is that polyester products P22 to P24 were prepared by replacing the catalyst with catalyst solutions C12 to C14, respectively.

Comparative example 7

126.0kg/h of 2, 6-naphthalenedicarboxylic acid, 65.0kg/h of 1, 3-propanediol and 0.25kg/h of propylene glycol solution of tetrabutyl titanate (the concentration of the tetrabutyl titanate is 40wt percent) are stirred and mixed, and the mixture enters an esterification unit for esterification reaction, wherein the temperature of a reaction material is 210 ℃, and the absolute pressure is 90KPa; mixing 90.5kg/h of adipic acid with 56.5kg/h of 1, 3-propylene glycol and 0.25kg/h of a propylene glycol solution of tetrabutyl titanate (the concentration of the tetrabutyl titanate is 40 wt%), stirring, and allowing the mixture to enter an esterification unit for esterification reaction, wherein the temperature of a reaction material is 180 ℃, the absolute pressure is 90KPa, and when the two groups of esterification rates reach 98%, fully mixing to obtain an esterified substance Z25;

the esterification product Z25 enters a polycondensation unit, the reaction temperature is 210 ℃, the absolute pressure is 4KPa, the reaction time is 2 hours, the absolute pressure is adjusted to 150Pa, the reaction temperature is 210 ℃, the reaction time is 2 hours, and a polyester intermediate M25 is obtained through pelletizing and drying;

the polyester resin intermediate M25264.6 kg/h, butyl ether 0.8kg/h, 2, 4-diphenylmethane diisocyanate 7.9kg/h and stannous octoate 2.6g/h continuously enter a static mixer for mixing and diffusion, a chain growth reaction is carried out at the temperature of 60 ℃, and a polyester product P25 is obtained after 4h.

Comparative example 8

A corresponding polyester product P26 was prepared according to example 3 of patent publication No. CN 103497316A.

Comparative example 9

The corresponding polyester product P27 was prepared according to example 1 of publication No. CN 103665777A.

Comparative example 10

A corresponding polyester product P28 was prepared according to example 2 of publication No. CN 111363131A.

The preparation method of the biodegradable aliphatic-aromatic copolyester sample film/sheet of the above examples and comparative examples: polyester sample particles are subjected to melt extrusion through a single-screw extrusion film blowing machine at the temperature of 150 ℃, then are cooled, blown and drawn to prepare a film with the thickness of 20 +/-5 mu m, and the blow-up ratio is 3, or are subjected to melt extrusion through a single-screw extrusion casting machine, then are cooled and drawn to prepare a sheet with the thickness of 200 +/-10 mu m, and the specific performance parameters are shown in the following table 1:

TABLE 1 quality parameters related to resin films/sheets

In conclusion, the aliphatic-aromatic copolyester prepared by the continuous production process has stable product and excellent quality, namely the carboxyl end groups of the resin are less than or equal to 25mmol/kg, and the gel points in the film/sheet are less than or equal to 35 gel points/m ² Mass average molecular weight of 6.7X 10 ⁴ ～14.7×10 ⁴ The molecular weight distribution is narrow between 1.8 and 2.6.

It should be noted that the above-mentioned embodiments are only for explaining the present invention, and do not constitute any limitation to the present invention. The present invention has been described in relation to an exemplary embodiment, and it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Modifications may be made to the invention as defined within the scope of the claims and modifications may be made without departing from the scope and spirit of the invention. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein, but rather extends to all other methods and applications having the same functionality.

Claims

1. A preparation method of aliphatic-aromatic copolyester comprises the following steps:

the auxiliary agent comprises a molecular weight increasing agent, and the molecular weight increasing agent comprises an isocyanate compound.

2. The method of claim 1, wherein the auxiliary agent further comprises a dispersing agent and an accelerator, preferably,

the diffusant comprises a compound having R ₁ -O-R ₂ An ether compound of the formula or having R ₃ COOR ₄ 、

One or more ester compounds of the general formula;

the promoter comprises a compound having

Or (R) ₇ ) _z M is one or more of metal organic matters of general formula, wherein R ₁ 、R ₂ And R ₇ Each independently selected from C ₁ ～C ₂₀ Hydrocarbyl radical, R ₃ 、R ₄ R' and R ₆ Each independently selected from C ₁ ～C ₁₉ A hydrocarbon radical, G is a divalent or trivalent C ₁ ～C ₂₀ Hydrocarbyl, optionally G is substituted with hydroxy, M is selected from Zn, mg, sn or Al, n is ≥ 1, y > 1, z > 1; preferably, the first and second electrodes are formed of a metal,

the diffusant comprises one or more of butyl ether, hexyl ether, tributyl citrate, dioctyl succinate or dioctyl adipate; and/or

The accelerant comprises one or more of stannous octoate, magnesium acetate, zinc acetate, magnesium laurate, dibutyl zinc or tetrabutyl tin; and/or

The diffusant, the molecular weight growth agent and the accelerator respectively account for 0.1-2%, 0.5-5% and 5 x 10% of the mass of the polyester intermediate ^-4 ～15×10 ^-4 ％。

3. The method of claim 2, wherein the isocyanate is of the formula

Wherein R is ₅ Is C ₁ ～C ₂₀ Hydrocarbyl, x > 1;

preferably, the isocyanate-based compound includes one or more of 2, 4-tolylene diisocyanate and its trimer, 2, 6-tolylene diisocyanate and its trimer, tetramethylxylylene diisocyanate, trimethylhexamethylene diisocyanate, xylylene diisocyanate, methylcyclohexane diisocyanate, 1, 6-hexamethylene diisocyanate and its trimer, 4 '-diphenylmethane diisocyanate, 2,4' -diphenylmethane diisocyanate, 2 '-diphenylmethane diisocyanate, dicyclohexylmethane-4, 4' -diisocyanate, or lysine diisocyanate.

4. A production method according to any one of claims 1 to 3, characterized in that the magnesium-containing compound is 0.01 to 10 moles, preferably 0.2 to 5 moles, per mole of titanium-containing compound; the zinc-containing compound is 0.01-10 mol, preferably 0.1-5 mol; 1 to 20 mol, preferably 1 to 10 mol of the hydroxyl-containing compound; the carboxyl-containing compound is 0.01 to 0.5 mol, preferably 0.1 to 0.5 mol; and/or the epoxy group-containing compound is 0.01 to 1mol, for example, 0.1 to 0.5 mol.

5. The method of any one of claims 1 to 4, wherein the titanium-containing compound is selected from the group consisting of compounds of the formula Ti (OR) ¹ ) _m X _4-m One OR more of the compounds and titanium oxides shown in the general formula Ti (OR) ¹ ) _m X _4-m In, R ¹ Is C ₂ ～C ₁₀ Is preferably C ₂ ～C ₆ A hydrocarbon group of (a); x is halogen, such as chlorine, bromine or iodine; m is an integer from 0 to 4, such as 0, 1,2, 3 or 4; preferably, the titanium-containing compound is selected from one or more of titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, tetraethyl titanate, tetraisopropyl titanate, tetrabutyl titanate and titanium dioxide; and/or

The magnesium-containing compound is selected from the general formula Mg (OR) ² ) ₂ X _2-n A compound of the formula and the general formula Mg (OOR) ³ ) ₂ One OR more of the compounds shown in the general formula Mg (OR) ² ) ₂ X _2-n In, R ² Is C ₂ ～C ₁₀ Is preferably C ₂ ～C ₆ X is halogen, such as chlorine, bromine or iodine; n is an integer from 0 to 2, such as 0, 1 or 2; general formula Mg (OOR) ³ ) ₂ In, R ³ Is C ₂ ～C ₁₀ Is preferably C ₂ ～C ₆ A hydrocarbon group of (a); preferably, the magnesium-containing compound is selected from one or more of magnesium dichloride, magnesium dibromide, magnesium diiodide, diethoxymagnesium, dipropoxymagnesium, diisopropoxymagnesium, dibutoxymagnesium, diisobutyoxymagnesium, magnesium acetate, magnesium propionate and magnesium butyrate; and/or

The zinc-containing compound is selected from the general formula Zn (OOR) ⁴ ) ₂ One or more of the compounds and zinc halides represented by the general formula Zn (OOR) ⁴ ) ₂ In, R ⁴ Is C ₂ ～C ₂₀ Is preferably C ₂ ～C ₁₀ Preferably, the zinc-containing compound is selected from one or more of zinc dichloride, zinc dibromide, zinc diiodide, zinc acetate, zinc propionate, zinc butyrate and zinc stearate; and/or

The hydroxyl-containing compound is selected from one or more of monohydric alcohol and polyhydric alcohol, and the monohydric alcohol is preferably C ₁ ～C ₁₀ Preferably 2 to 6, such as C ₂ ～C ₁₀ Diol of (2), C ₃ ～C ₁₅ Trihydric alcohol of (1), C ₄ ～C ₂₀ Tetrahydric alcohol of (1), C ₅ ～C ₂₀ Pentahydric alcohol or C of ₆ ～C ₂₀ A hexahydric alcohol of (1); preferably, the hydroxyl group-containing compound is selected from one or more of methanol, ethanol, isopropanol, n-butanol, n-pentanol, 2-pentanol, 3-pentanol, ethylene glycol, 1, 3-propanediol, 1, 4-butanediol, 1, 5-pentanediol, pentaerythritol, and sorbitol; and/or

The carboxyl-containing compound is selected from one or more of monocarboxylic acid and polycarboxylic acid, and the monocarboxylic acid is preferably C ₁ ～C ₂₀ Preferably a polycarboxylic acid of (2), said polycarboxylic acid preferably being C ₂ ～C ₂₀ Of dicarboxylic acids or C ₃ ～C ₂₀ The tricarboxylic acid of (a); preferably, the carboxyl-group-containing compound is at least one selected from the group consisting of formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, stearic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, and adipic acid; and/or

The compound containing epoxy group is selected from the general formula

One or more of the compounds shown in the general formula

In, R ⁵ And R ⁶ Same or different, each is independently selected from hydrogen or C ₁ ～C ₂₀ Preferably selected from hydrogen or C ₁ ～C ₁₀ Preferably, the epoxy group-containing compound is selected from one or more of ethylene oxide, propylene oxide, 1, 2-butylene oxide, 1, 4-butylene oxide or 1, 2-pentylene oxide.

6. The production method according to any one of claims 1 to 5,

the aliphatic dibasic acid is selected from C ₂ ～C ₁₆ Aliphatic dibasic acid of (1), C ₂ ～C ₁₆ Aliphatic dicarboxylic anhydrides or C ₂ ～C ₁₆ Preferably selected from C ₂ ～C ₁₀ Aliphatic dibasic acid of (1), C ₂ ～C ₁₀ Aliphatic dicarboxylic anhydrides or C ₂ ～C ₁₀ One or more of the aliphatic dicarboxylic acid halides of (a); more preferably, the aliphatic dibasic acid comprises one or more of succinic acid, glutaric acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, 1, 4-cyclohexanedicarboxylic acid, glutaric anhydride, or malonyl chloride;

the aromatic dibasic acid is selected from C ₈ ～C ₁₆ Aromatic dibasic acid of (1), C ₈ ～C ₁₆ Or C is an aromatic dibasic acid anhydride ₈ ～C ₁₆ Preferably, the aromatic diacid halide comprises one or more of terephthalic acid, terephthalic anhydride, terephthalic acid halide, isophthalic acid, isophthalic anhydride, isophthaloyl halide, naphthalene dicarboxylic acid, naphthalene dicarboxylic anhydride, naphthalene dicarboxylic acid halide;

the aliphatic diol is selected from C ₂ ～C ₁₀ Preferably selected from C ₂ ～C ₆ One or more of the aliphatic diols of (a); more preferably, the aliphatic diol comprises one or more of ethylene glycol, 1, 2-propylene glycol, 1, 3-propylene glycol, 1, 4-butanediol, 1, 5-pentanediol, neopentyl glycol, 1, 6-hexanediol, or a polyether diol; it is further preferred that the first and second liquid crystal display panels,

in the aliphatic dibasic acid, the aromatic dibasic acid and the aliphatic dihydric alcohol, the molar content of the hydroxyl functional group and the molar content of the total functional groups of the carboxylic acid, the acid anhydride and the acyl halide are (1.2-2.5): 1.

7. the production method according to any one of claims 1 to 6,

in the step S1, the temperature of the esterification reaction is 150-250 ℃, the absolute pressure is 40-110 KPa, and the reaction time is 2-6 h;

in the step S2, the polycondensation reaction comprises a first polycondensation reaction and a second polycondensation reaction which are sequentially carried out, wherein the temperature of the first polycondensation reaction is 220-250 ℃, the absolute pressure is 1 KPa-5 KPa, the time is 1 h-3 h, the temperature of the second polycondensation reaction is 220-250 ℃, the absolute pressure is 10 Pa-300 Pa, and the time is 1 h-3 h;

in the step S3, the temperature of the chain growth reaction is 25-100 ℃, and the time is 4-24 h.

8. The process according to any one of claims 1 to 7, wherein in step S1, the esterification reaction products are mixed with an esterification rate of 98% or more; and/or

And the step S2 also comprises the steps of granulating and drying after the polycondensation reaction to obtain the polyester intermediate.

9. An aliphatic-aromatic copolyester obtained by the preparation method according to any one of claims 1 to 8, wherein the aliphatic-aromatic copolyester satisfies at least one of the following conditions (a) to (e):

(a) The intrinsic viscosity of the aliphatic-aromatic copolyester is 1.6 to 1.8dl/g;

(b) The content of the end carboxyl groups of the aliphatic-aromatic copolyester is less than or equal to 25mmol/kg, preferably less than or equal to 15mmol/kg;

(c) The gel point of the aliphatic-aromatic copolyester is less than or equal to 35/m ² Preferably 10 or less per m ² ；

(d) The aliphatic-aromatic copolyester has a mass average molecular weight of 6.7 x 10 ⁴ ～14.7×10 ⁴ Preferably 10.1X 10 ⁴ ～14.7×10 ⁴ ；

(e) The molecular weight distribution of the aliphatic-aromatic copolyester is 1.8-2.6, preferably 1.8-2.1.

10. Use of an aliphatic-aromatic copolyester according to claim 9 in a polyester film material or a polyester sheet material.