WO2010025590A1

WO2010025590A1 - Catalyst for producing polybutylene succinate and copolyester thereof, and preparing methods of the catalyst

Info

Publication number: WO2010025590A1
Application number: PCT/CN2008/002110
Authority: WO
Inventors: 孔凡滔; 杨景辉; 吴秋芳; 马新胜; 李福清
Original assignee: 上海华明高技术（集团）有限公司
Priority date: 2008-09-08
Filing date: 2008-12-29
Publication date: 2010-03-11
Also published as: US20110162205A1; CN101671435A; CN101671435B

Abstract

Preparing methods of catalyst for producing polybutylene succinate and copolyester thereof, which comprise (1) adding titanium alcoholate, silicon alcoholate, glycol and metal cocatalyst to solvent, reacting at 80-180℃, and removing unreacted substances and small molecule products from the reaction system, (2) adding complexing agent and continuing the reaction, then removing small molecules and collecting the catalyst from reaction products; or which comprise (1) adding titanium alcoholate, glycol and metal cocatalyst to solvent, reacting at 80-180℃, and removing unreacted substances and small molecule products from the reaction system, (2) adding silicon alcoholate and complexing agent and continuing the reaction, then removing small molecules and collecting the catalyst from reaction products.

Description

Technical field

The invention relates to a catalyst for the preparation of polybutylene succinate and its copolyester.

Background technique

Aliphatic polyesters have attracted a lot of attention and research because of their good biodegradability and environmental pollution. Among them, polybutylene succinate (PBS) and its copolyester have the good mechanical properties and processing properties, and become the most easy to realize practical application in aliphatic polyester, which is the focus of the industry. .

The production of polybutylene succinate and its copolyesters generally employs two methods: chain extension and direct polycondensation. The chain extension method uses a chain extender to react with an organic group of the polyester to increase the molecular weight of the polyester. The main chain extenders currently used are diisocyanate alkoxides, which are toxic and therefore cannot be used in the field of contact with foods, and to some extent limit polybutylene succinate and its Copolyester application. Compared with the chain extension method, the direct polycondensation method does not use a toxic chain extender, and the production process and production equipment are very similar to other polyesters (such as polyethylene terephthalate), so it is likely to become a future gathering. Mainstream process for the production of butylene succinate and its copolyesters.

The direct polycondensation method is used for the synthesis of polybutylene succinate and its copolyester. It is necessary to add a polycondensation catalyst to the reaction system. The catalyst used is mainly a titanium catalyst or a mixture of a titanium catalyst and other metal catalysts. For example, the catalysts used in CN1424339 are tin oxide, antimony trioxide, cadmium acetate and titanium alkoxide; and the catalysts used in the patent CN1861660A are n-butyl titanate, isopropyl titanate, antimony trioxide and tannic acid. N-butyl ester. In actual production, the individual titanate catalysts often do not fully meet the requirements, and need to be compounded with other compounds to form a composite catalyst. The above catalyst systems all have certain technical defects, mainly as follows: (1) The activity of the catalyst is low, and the amount of addition is high, which affects the quality of the final product. Usually, a titanium alkoxide catalyst is used, and the active ingredient (titanium element) is added in an amount of more than 500 ppm based on polybutylene succinate (ie, 500 X 10- ⁶ g Ti/g PBS, the same below), and sometimes even exceeds 700 ppm, such a high addition amount will lead to the occurrence of more side reactions and increase the melt mass flow rate of the product, the mechanical properties are degraded, and the color is severely yellowed. (2) The catalyst is inconvenient to use and causes difficulties in production operations. Titanium alkoxides are precipitated when exposed to water at normal temperature. In the synthesis of PBS, the product in the esterification stage is water. Therefore, titanium alkoxides can be added as esters after esterification but not in esterification. Pre-addition; On the other hand, the simultaneous use of multiple substances as catalysts also poses certain difficulties in the addition. The operator needs to prepare the catalyst in advance, which is far less convenient than using a single catalyst. Summary of the invention

SUMMARY OF THE INVENTION An object of the present invention is to provide a catalyst for preparing polybutylene succinate and a copolyester thereof and a process for the preparation thereof, which overcome the above-mentioned drawbacks of the prior art.

One of the preparation methods of the catalyst of the present invention comprises the following steps:

The titanium alkoxide, the silicon alkoxide, the diol and the metal promoter are added to the solvent, and the reaction is carried out for 0.5 to 2.5 hours, the reaction temperature is 80 to 180 ° C, and the reaction temperature is preferably 85 to 160 ° C, and the reaction system is separated and removed. The reacted substance and the small molecule product are then added to the complexing agent for 0.5 to 2.5 hours, the reaction temperature is 80 to 180 ° C, and the preferred reaction temperature is 85 to 160 ° C, and the small molecules are separated and removed, and then collected from the reaction product. The catalyst;

The second method for preparing the catalyst of the present invention comprises the following steps:

The titanium alkoxide, the glycol and the metal promoter are added to the solvent, and the reaction is carried out for 0.5 to 2.5 hours, the reaction temperature is 80 to 180 ° C, and the reaction temperature is preferably 85 to 160 ° C, and the unreacted substances in the reaction system are separated and removed. The small molecule product is then reacted for 0.5 to 2.5 hours, the reaction temperature is 80 to 180 ° C, preferably the reaction temperature is 85 to 160 ° C, and the small molecule is separated and removed, and then the reaction is carried out for 0.5 to 2.5 hours. Collecting the catalyst in the reaction product;

The method for separating and removing unreacted substances and small molecule products in the reaction system is a conventional method such as a conventional distillation or rectification method;

The titanium alkoxide is a mixture of one or both of n-butyl titanate or isopropyl titanate; the silicon alkoxide is one of methyl orthosilicate or ethyl orthosilicate. Or a mixture of the two; the inventors have surprisingly found that the choice of metal promoter and complexing agent has a greater impact on the present invention and will directly affect the activity and selectivity of the catalyst. To this end, the inventors have selected a large number of tests to select as follows:

The metal promoter is selected from one or more of the acetate or alkoxide of a metal element of the group of lanthanum, cerium, IIB, VIIIB, preferably zinc acetate, aluminum isopropoxide, calcium acetate, magnesium acetate. Or a mixture of one or more of manganese acetate;

The diol is 1,4-butanediol, ethylene glycol, 1,3-propanediol, 2-methyl-2,4-pentanediol, 1,5-pentanediol or 1,6- a mixture of one or any of several hexanediols;

The complexing agent is a phosphate ester and a hydroxycarboxylic acid;

The phosphate ester is preferably one or a mixture of any of trimethyl phosphate, trimethyl phosphite, triethyl phosphate or triethyl phosphite;

The hydroxycarboxylic acid is preferably one or a mixture of any of citric acid, tartaric acid or lactic acid;

The solvent is one or a mixture of any one of ethanol, n-butanol or isopropanol; the molar ratio of the titanium atom to the total amount of the diol is 1:5 to 1:30, preferably 1:20. 〜1:30; the molar ratio of the titanium atom to the total amount of the promoter metal element is 1:0.05~1:2, preferably 1:0.05-1:0.5;

The molar ratio of the titanium atom to the hydroxycarboxylic acid is 1:0.5~1:2, preferably l:0.5~l.5;

The molar ratio of the titanium atom to the silicon atom is 1:0.01 to 1:2, preferably 1:0.05 to 1:1; The molar ratio of the titanium atom to the phosphorus atom is 1:0.01 to 1:2, preferably 1:0.01 to 1 _: 1.5; the molar ratio of the titanium atom to the total amount of the solvent is 1:5 to 1:50, preferably 1:5. ~1 :30.

The catalyst prepared by the above method can be used for preparing polybutylene succinate and its copolyester. When succinic acid and 1,4-butanediol are used as main monomers, polybutyl succinate is prepared. In the case of a glycol ester and a copolyester thereof, the catalyst may be directly added to the reaction system or diluted in 1,4-butanediol and added to the reaction system, and may be added to the reaction system before the esterification reaction. After the end of the esterification reaction, the reaction system is added before the start of the pre-polycondensation reaction.

The catalyst is added in an amount of 80 X 10- ⁶ to 200 X 10' ⁶ o by weight of the titanium atom to polybutylene succinate and its copolyester.

The catalyst is added in an amount such that the weight ratio of the titanium atom to the polybutylene succinate and the copolyester thereof is preferably 100 Χ 1 (Γ ⁶ ～ 150 Χ 1 (Τ ^ό .

Since the catalyst adopts a complexing technique and directly introduces a metal promoter in the catalyst, it has the following advantages compared with the currently used titanium alkoxide catalyst: (1) high catalytic activity, low added amount, product Good quality; (2) The synthesis of polybutylene succinate and its copolyester can be used alone, without the use of other materials, eliminating the need for mixing of different catalysts; (3) The catalyst does not react with water at normal temperature, and may be added before the esterification reaction or after the esterification reaction, before the pre-polycondensation reaction, and is easy to store for a long period of time.

In summary, the catalyst has good industrial application prospects and value.

detailed description

The invention is described in more detail with the aid of the following examples, but it should be noted that the invention is not limited to the embodiments, and the non-essential changes and adjustments made by the ordinary in the It is still within the scope of protection of the present invention.

In the following examples, the melt mass flow rate of polybutylene succinate is measured according to GB/T 3682-2000 Thermoplastic melt mass flow rate and melt volume flow rate. Determine the method. The color of polybutylene succinate was evaluated using the L, a, b color system. In this system, L is the lightness factor and a and b are the color measurements. b indicates the balance of yellow and blue, which is very important for the color of polyester. The lower the b value, the better the color.

Example 1

50 g of 4-butanediol (0.55 mol) was placed in a 250 ml flask equipped with a stirring paddle and a condensing device, 1.73 g of calcium acetate (0.0098 mol) was dissolved therein, and then 29 g of n-butyl titanate was added to the solution ( 0.0852 mol) and 31.51 g ethanol (0.685 mol) at 80. After C reaction for 2.5 h, the small molecule was distilled off, and then 2.04 g of tetraethyl orthosilicate (0.0098 mol) and 8.22 g of tartaric acid (0.0548 mol) were added to the reaction system, and reacted at 80 ° C for 2.5 h to distill off the small molecule. That is, a liquid catalyst containing 5.12% of titanium is obtained.

Example 2

50 g of 4-butanediol (0.55 mol) was placed in a 250 ml flask equipped with a stirring paddle and a condensing device, 2.4 g of manganese acetate (0.0098 mol) was dissolved therein, and then 19.44 g of isopropyl titanate was added to the solution. (0.0685 mol) and 31.51 g of ethanol (0.685 mol) were reacted at 110 ° C for 0.5 h. After distilling off the small molecule, 1.02 g of tetraethyl orthosilicate (0.0049 mol) and 12.76 g of trimethyl phosphite (0.1028 mol) were added to the reaction system, and reacted at 110 ° C for 0.5 h to distill off the small molecules. That is, a liquid catalyst containing 4.14% of titanium was obtained.

Example 3

50 g of 4-butanediol (0.55 mol) was placed in a 250 ml flask equipped with a stirring paddle and a condensing device, 2.2 g of zinc acetate (0.1 mol) was dissolved therein, and then 22.80 g of n-titanate was added to the solution. The ester (0.067 mol) and 92.46 g of ethanol (2.01 mol) were reacted at 180 ° C for 1 h. After distilling off the small molecule, 8.41 g of citric acid (0.04 mol), 5.10 g of tartaric acid (0.034 mol), 2.08 g of tetraethyl orthosilicate (0.0 mol) and 6.74 g of triethyl phosphate (0.037) were added to the reaction system. Mol), after reacting at 180 ° C for 1 h, distilling off small molecules, then preparing a liquid catalyst containing 4.02% of titanium. Example 4

To a 250 ml flask equipped with a stirring paddle and a condensing device, 100 g of 4-butanediol (11 lmol) was added thereto, 3.29 g of zinc acetate (0.015 mol) was dissolved therein, and then 10.21 g of n-butyl titanate was added to the solution. (0.03 mol), 8.517 g of isopropyl titanate (0.03 mol), 3.12 g of ethyl orthosilicate

(0.015 mol) and 46 g of ethanol (lmol) were reacted at 100 ° C for 1 h. After distilling off the small molecule, 9.05 g of lactic acid (0.105 mol) and 14.22 g of trimethyl phosphate (0.1 mol) were added to the reaction system, and reacted at 150 ° C for 1.2 h to distill off the small molecule, thereby preparing Titanium 2.01% liquid catalyst.

Example 5

50 g of 4-butanediol (0.55 mol) was added to a 250 ml flask equipped with a stirring paddle and a condensing device, and 3.22 g of magnesium acetate (0.015 mol) and 1.02 g of aluminum isopropoxide (0.005 mol) were dissolved therein, and then To the solution were added 22.80 g of n-butyl titanate (0.067 mol), 3.12 g of tetraethyl orthosilicate (0.015 mol) and 46 g of ethanol (1 mol), and reacted at 80 ° C for 2.5 h. After distilling off the small molecule, 10.06 g of tartaric acid (0.067 mol) and 18.22 g of triethyl phosphate (0.1 mol) were added to the reaction system, and reacted at 80 ° C for 1.2 h to distill off the small molecule, thereby preparing Titanium 3.24% liquid catalyst.

Example 6

50 g of 4-butanediol (0.55 mol) was added to a 250 ml flask equipped with a stirring paddle and a condensing device, and 3.29 g of zinc acetate (0.015 mol) and 1.76 g of calcium acetate (0.0 mol) were dissolved therein, and then To the solution were added 22.80 g of n-butyl titanate (0.067 mol) and 46 g of ethanol (1 mol), and reacted at 180 Torr for 1.8 h. After distilling off the small molecule, 7.04 g of citric acid (0.034 mol) > 2.28 g of methyl orthosilicate (0.015 mol) and 14.22 g of trimethyl phosphate (0.1 mol) were added to the reaction system, and the reaction was carried out at 120 ° C. 2h, after distilling off the small molecules, a liquid catalyst containing 3.49% of titanium was obtained.

Example 7

Add 50 gl, 4-butanediol to a 250 ml flask equipped with a stirring paddle and a condensing unit (0.55 mol), 2.04 g of aluminum isopropoxide (0.0 mol) and 2.45 g of manganese acetate (0.1 mol) were dissolved therein, and then 22.80 g of n-butyl titanate (0.067 mol) and 46 g of ethanol were added to the solution. (lmol), reacted at 80 ° C for 2.5 h. After distilling off the small molecule, 10.55 g of citric acid (0.050 mol), 3.12 g of tetraethyl orthosilicate (0.015 mol) and 12.41 g of trimethyl phosphite (0.1 mol) were added to the reaction system at 80 ° C. After reacting for 2.5 hours and distilling off the small molecules, a liquid catalyst containing 3.42% of titanium was obtained.

Example 8

31 g of ethylene glycol (0.5 mol) and 45.45 g of 4-butanediol (0.5 mol) were placed in a 250 ml flask equipped with a stirring paddle and a condensing device, and 2.04 g of aluminum isopropoxide (O. Olmol) was dissolved therein. And 1.73 g of calcium acetate (0.0098 mol), then 22.80 g of n-butyl titanate (0.067 mol) and 31 g of ethanol (0.67 mol) were added to the solution, and reacted at 80 ° C for 2.5 h. After distilling off the small molecule, 14.14 g of citric acid (0.067 mol), 13.96 g of tetraethyl orthosilicate (0.067 mol) and 12.41 g of trimethyl phosphite (0.1 mol) were added to the reaction system at 80 ° C. After reacting for 2.5 hours, the small molecule was distilled off to obtain a liquid catalyst containing 2.34% of titanium.

Example 9

6 mol of succinic acid was uniformly mixed with 7.2 mol, 4-butanediol, and 2.4 g of a catalyst solution prepared according to Example 1 (Ti content: 123 ppm) was added. The esterification reaction was carried out at 23 (TC). After the end of the esterification reaction, the polycondensation reaction was started. The final polycondensation reaction was carried out at 240 ° C and a pressure of 35 Pa. After 120 minutes of reaction time, a melt mass flow rate of 15 g / was obtained. 10 min, a polybutylene succinate having a b value of 4.2.

Example 10

6 mol of succinic acid and 7.2 mol, 4-butanediol were uniformly mixed, and esterification reaction was carried out at 230-240 ° C. When the amount of esterified water reached more than 90% of the theoretical water content, it was added according to Example 2. The catalyst solution was 3.6 g (Ti content 150 ppm), and the polycondensation reaction was started after mixing uniformly. End The polycondensation reaction was carried out at 240 ° C and a pressure of 35 Pa. After a reaction time of 120 minutes, a polybutylene succinate having a melt mass flow rate of 6 g/10 min and a b value of 7.0 was obtained.

Example 11

In the same manner as in Example 10, except that 2.5 g of the liquid catalyst prepared in Example 3 (ti content of 100 ppm) was added, after a final polycondensation reaction time of 140 minutes, a melt mass flow rate of 16 g/10 min was obtained. Polybutylene succinate having a b value of 5.6.

Example 12

In the same manner as in Example 10, except that 7 g of the liquid catalyst prepared in Example 4 (Ti content: 140 ppm) was added, after a final polycondensation reaction time of 105 minutes, a melt mass flow rate of 20 g/10 min was obtained, b. A polybutylene succinate having a value of 4.5.

Example 13

In the same manner as in Example 9, except that 4 g of the liquid catalyst prepared in Example 5 (Ti content: 130 ppm) was added, after a final polycondensation reaction time of 108 minutes, a melt mass flow rate of 18 g/10 min was obtained, b. A polybutylene succinate having a value of 4.9.

Example 14

In the same manner as in Example 10, except that 3 g of the liquid catalyst prepared in Example 6 (Ti content: 105 ppm) was added, after a final polycondensation reaction time of 134 minutes, a melt mass flow rate of 16 g/10 min was obtained, b. A polybutylene succinate having a value of 5.3.

Example 15

In the same manner as in Example 10, except that 3.5 g of the liquid catalyst prepared in Example 7 (Ti content: 120 ppm) was added, after a final polycondensation reaction time of 125 minutes, a melt mass flow rate of 19 g/10 min was obtained. Polybutylene succinate having a b value of 3.9.

Example 16

Mixing 5 moles of succinic acid, 1 mole of terephthalic acid, 6mol, 4-butanediol and 1.3mol of ethylene glycol Evenly, the esterification reaction is carried out at 230-250 ° C. When the amount of the esterified water reaches 90% or more of the theoretical water output, 6.4 g (Ti content 150 ppm) of the catalyst solution prepared according to Example 8 is added, and the mixture is mixed. The polycondensation reaction is started afterwards. The final polycondensation reaction was carried out at 275 ° C and a pressure of 35 Pa. After 140 minutes of reaction time, a polybutylene succinate and a polyethylene terephthalate having a melt mass flow rate of 8 g/10 min and a b value of 6.2 were obtained. Copolyester of glycol esters.

Comparative example

In the same manner as in Example 10, except that 4 g of tetrabutyl titanate (Ti content: 560 ppm) was added, after a final polycondensation reaction time of 125 minutes, a melt mass flow rate of 25 g/10 min and a b value of 15.7 were obtained. Polybutylene succinate.

Claims

Rights request

A method for preparing a catalyst for preparing polybutylene succinate and a copolyester thereof, characterized by comprising the steps of:

(1) reacting a titanium alkoxide, a silicon alkoxide, a glycol and a metal promoter in a solvent at a reaction temperature of 80 to 180 ° C to separate and remove unreacted substances and small molecule products in the reaction system;

(2) Then, a complexing agent is added, the reaction temperature is 80 to 180 ° C, small molecules are separated and removed, and then the catalyst is collected from the reaction product.

The method according to claim 1, wherein the reaction time of the step (1) is from 0.5 to 2.5 hours, and the reaction temperature is preferably from 85 to 160 °C.

The method according to claim 1, wherein the reaction time of the step (2) is 0.5 to 2.5 hours, and the reaction temperature is preferably 85 to 160 °C.

A method for preparing a catalyst for preparing polybutylene succinate and a copolyester thereof, comprising the steps of:

(1) reacting a titanium alkoxide, a glycol and a metal promoter into a solvent at a reaction temperature of 80 to 180 ° C to separate and remove unreacted substances and small molecule products in the reaction system;

(2) Then, a silicon alkoxide and a complexing agent are added, the reaction temperature is 80 to 180 ° C, the small molecules are separated and removed, and then the catalyst is collected from the reaction product.

The method according to claim 4, wherein in the step (1), the reaction time is 0.5 to 2.5 hours, and the reaction temperature is preferably 85 to 160 °C.

The method according to claim 4, wherein in the step (2), the reaction time is 0.5 to 2.5 hours, and the reaction temperature is preferably 85 to 160°.

The method according to any one of claims 1 to 6, wherein the titanium alkoxide is one or a mixture of two or more of n-butyl titanate or isopropyl titanate. The silicon alkoxide is one or a mixture of two of orthosilicate or tetraethyl orthosilicate.

The method according to any one of claims 1 to 6, wherein the metal promoter is one selected from the group consisting of IIA, IIIA, an acetate or an alkoxide of a metal element of Group VIIIB. Or several

The solvent is one or a mixture of any one of ethanol, n-butanol or isopropanol; the complexing agent is a phosphate ester and a hydroxycarboxylic acid.

9. The method according to claim 8, wherein the metal promoter is a mixture of one or more of zinc acetate, aluminum isopropoxide, calcium acetate, magnesium acetate or manganese acetate; The phosphate ester is one or a mixture of trimethyl phosphate, trimethyl phosphite, triethyl phosphate or triethyl phosphite;

The hydroxycarboxylic acid is one or a mixture of citric acid, tartaric acid or lactic acid;

Atomic molar ratio of titanium to the total amount of diol is 1: 5 to 1: 30, preferably from 1: 20 to _1:30; the molar ratio of titanium atoms to the total amount of the promoter metal element is 1: 0.05~ 1:2, preferably 1:0.05-1:0.5;

The molar ratio of titanium atom with a hydroxy carboxylic acid is 1: 0.5 to 1: 2, preferably _1: 0.5~1: 1.5; molar ratio of titanium atoms to silicon atoms is 1: 0.01~1: 2, preferably 1 : 0.05~1:1; the molar ratio of titanium atom to phosphorus atom is 1:0.01~1:2, preferably 1:0.01~1:1.5; the molar ratio of titanium atom to total solvent is 1:5~1 : 50, preferably 1:5 to 1:30.

10. A catalyst for the preparation of polybutylene succinate and its copolyester prepared by the process according to any one of claims 1 to 9.