CN1962719A - Method for preparing polyester - Google Patents
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- CN1962719A CN1962719A CN 200510110290 CN200510110290A CN1962719A CN 1962719 A CN1962719 A CN 1962719A CN 200510110290 CN200510110290 CN 200510110290 CN 200510110290 A CN200510110290 A CN 200510110290A CN 1962719 A CN1962719 A CN 1962719A
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Abstract
The invention discloses a preparing method of polyester catalyst, which is characterized by the following: adopting the reacting product of titanium compound, phosphor compound and polyol as dicarboxylic acids and reacting catalyst of alkylidene glycol; fitting for industrial manufacturing course of polymer.
Description
Technical field
The present invention relates to a kind of method of producing polyester.
Background technology
Polyester as polyethylene terephthalate etc., has excellent machinery, physics and chemical property, is widely used in goods such as various fibers, film, sheet material.
The research autopolyester of polyester catalyst had never stopped since coming out, and industrial production and the more polyester catalyst of research mainly are the catalyzer of antimony, germanium and three series of titanium at present, and wherein using most often, antimony-based catalyst (comprises Sb
2O
3, SbAc
3With antimony glycol etc.), 90% polyester is produced by antimony-based catalyst in the world at present.The shortcoming of antimony-based catalyst is: low activity; Heavy metal catalyst pollutes environment; The polymer belt grey.The germanium series catalysts has satisfactory stability, and the side reaction that causes in reaction process is less, and made PET hue is good, but because resource is few, costs an arm and a leg.Titanium series catalyst has high reactivity, but the polyester that Titanium series catalyst makes exists poor stability and goods yellowing, muddy problem, thereby is never used on a large scale.
More and more pay close attention in the whole world under the background of environment for human survival, the production and selling of green textiles will be the trend of following textiles development, can the developed country that with the European Union is representative reach green textile standards more and more as the condition that comes into the market, development through 10 years, European Union's eco-label (Eco-label) is approved by the human consumer of European Union gradually, the pouplarity of sticking on the Ecolabelling commodity also improves gradually, many downstream manufacturers, especially sportwear manufacturer is very interested in not stibiated polyester, and it is not stibiated that this trend makes that production of polyester producer is devoted to exploitation, eco-friendly catalyzer.
Titanium series catalyst is because it is active high, do not contain heavy metal, thereby be subjected to the favor of numerous polyester producers, Titanium series catalyst also is the research focus of polyester catalyst in recent years, company more than ten American-European and Japan has carried out the development of titanium series polyester catalyst, the domestic research work that also has many companies and research institution to carry out this respect of China.Along with the development of molecular designing and catalyst preparation technology, people expectation is carried out modification on traditional titanate catalyst basis, develop environmental protection, highly active and can overcome the Novel Titanium series catalysts of traditional in the past titanium series polyester catalyst shortcoming.Existing many at present companies announce to have succeeded in developing the Novel Titanium series polyester catalyst of excellent property, and commercially produced product can be provided.This Sustainable development to polyester industrial will bring great promoter action.
CN1403464 has reported a kind of preparation of ethylene glycol salt of titanium, adopts titanium tetrachloride and glycol reaction, obtains the ethylene glycol salt of titanium.
The CN1327985 report adopts tetrabutyl titanate and dibasic alcohol or moisture diol reaction, has prepared the binary titanium alkoxide compound.
The diatomic alcohol compounds of titanium is during as polyester catalyst, and still there is the problem of color jaundice in prepared polyester, and catalyzer have in the presence of the water stable bad.
As everyone knows, catalyzer should have dispersiveness preferably in the middle of raw material in the production of polyester, and the diatomic alcohol compounds of the titanium that above-mentioned patent is reported all is a solid, and it is unfavorable greatly that this makes that the production of polyester brings.
The inventor provides the method for producing polyester, in the presence of titanium catalyst, makes to comprise at least a aromatic dicarboxylic acid or its ester derivative and the diol reaction of being selected from.The titanium catalyst that is adopted is to react the homogeneous catalyst that obtains dissolving in ethylene glycol by titanium compound, phosphorus compound and alcohol, adopts the polyester of this class Catalyst Production to have good form and aspect.
Summary of the invention
Technical problem to be solved by this invention is the bad problem of di-alcohols compound solvability in ethylene glycol of the titanium that exists in the prior art, a kind of new method that is used to produce polyester is provided, the catalyzer that this method has a use dissolves in ethylene glycol and becomes homogeneous catalyst, and the polyester that makes has the good characteristics of form and aspect.
In order to solve the problems of the technologies described above, the technical solution used in the present invention is as follows: a kind of method of producing polyester, with di-carboxylic acid and aklylene glycol is raw material, in the presence of titanium-containing catalyst, in temperature of reaction is 230～280 ℃, reaction pressure is to carry out esterification under normal pressure～0.5MPa condition, obtain prepolymer, it is 250～320 ℃ in temperature of reaction then, reaction pressure is for to get polyester product less than carrying out polycondensation under the vacuum condition of 150Pa, and wherein titanium-containing catalyst comprises the reaction product of following material:
(a) have the titanium compound of following general formula:
Ti(OR)
4
R is the alkyl that is selected from 1～10 carbon atom;
(b) be selected from the phosphorus compound of phosphate compounds, phosphite ester compound or its mixture;
(c) be selected from polyvalent alcohol with 2～10 carbon atoms.
In the technique scheme, the di-carboxylic acid preferred version is selected from least a in terephthalic acid, phthalic acid, m-phthalic acid, naphthalic acid, biphenyl dicarboxylic acid or the cyclohexane dicarboxylic acid; The aklylene glycol preferred version is selected from ethylene glycol, 1,3 propylene glycol, propylene glycol, 1, at least a in the 4-butyleneglycol.The consumption of titanium-containing catalyst is 1～100PPm in the polyester amount preferable range that generates, and more preferably scope is 1～40PPm.The titanium compound preferred version is selected from least a in metatitanic acid tetramethyl ester, tetraethyl titanate, metatitanic acid orthocarbonate, titanium isopropylate or the tetrabutyl titanate.The phosphate compounds preferred version is selected from least a in trimethyl phosphite 99, triethyl phosphate, tricresyl phosphate propyl ester, tricresyl phosphate isopropyl ester, tributyl phosphate or the triphenylphosphate; The phosphite ester compound preferred version is selected from least a in dimethylphosphite, diethyl phosphite, phosphorous acid dipropyl, diisopropyl phosphite, dibutyl phosphite or the phosphorous acid diphenyl ester.The polyvalent alcohol preferred version is selected from ethylene glycol, 1,2-propylene glycol, 1,3 propylene glycol, 1,4-butyleneglycol, 1, at least a in 6-hexylene glycol, glycerine, TriMethylolPropane(TMP) or the tetramethylolmethane.The mol ratio preferable range of phosphorus compound and titanium compound is 0.5～10: 1; The mol ratio preferable range of polyvalent alcohol and titanium compound is 1～800: 1.
Among the present invention when the mol ratio of phosphorus compound and titanium compound less than 0.5 the time, the form and aspect of the polyester that the catalyzer of gained generates are difficult to satisfactory, when the mol ratio of phosphorus compound and titanium compound greater than 10 the time, activity of such catalysts is lower.
The mol ratio of the pure and mild titanium compound described in the present invention is more than or equal to 1, when the mol ratio of pure and mild titanium compound less than 1 the time, the catalyst tolerates water-based that makes is bad.
The Preparation of catalysts mode is not specifically limited among the present invention, a kind of the carrying out in can be as follows:
1, with titanium compound and alcohol reaction, reacts with phosphorus compound again;
2, earlier with titanium compound and alcohol reaction, the product with this reaction product and phosphorus compound and alcohol reaction reacts again;
3,, react with alcohol again after this reaction product and the phosphorus compound reaction with titanium compound and alcohol reaction;
4, titanium compound and phosphorus compound and alcohol are reacted simultaneously.
In this reaction, temperature of reaction is 30～250 ℃.Among the present invention reaction pressure there is not clear and definite restriction.
The preparation method of polyester is as follows:
Among the preparation method of polyester, raw material uses di-carboxylic acid or its to become ester derivative and dibasic alcohol among the present invention, preferably uses aromatic dicarboxylate or its to become ester derivative and aliphatic dihydroxy alcohol.
Be used for di-carboxylic acid of the present invention and comprise the aromatic dicarboxylate, as terephthalic acid, phthalic acid, m-phthalic acid, naphthalic acid, biphenyl dicarboxylic acid, and alicyclic carboxylic acid such as cyclohexane dicarboxylic acid etc., preferred terephthalic acid.
The example of dibasic alcohol comprises aliphatic dihydroxy alcohol such as ethylene glycol, 1, ammediol, propylene glycol, 1,4-butyleneglycol etc., preferred ethylene glycol.
Preparation process of polyester of the present invention, can adopt known preparation process of polyester, the first step is carried out esterification by terephthalic acid or dimethyl terephthalate (DMT) and ethylene glycol, obtains prepolymer, esterification is carried out at 230～280 ℃, and pressure is normal pressure～0.5MPa.Second step was carried out polycondensation under high vacuum, 250～320 ℃ of temperature of reaction, and pressure is lower than 150Pa.The adding of catalyzer can join in the reaction system simultaneously with phthalic acid or dimethyl terephthalate (DMT) and ethylene glycol, also can join in the reaction system after phthalic acid or dimethyl terephthalate (DMT) and glycol reaction generate prepolymer.
In the present invention, test by the following method such as the limiting viscosity of polyester, end carboxyl, glycol ether and form and aspect:
1) limiting viscosity: the mixed liquid of phenol-tetrachloroethane is made solvent, uses determination of ubbelohde viscometer under 25 ℃ the temperature.
2) end carboxyl: make solvent with ortho-cresol, potassium hydroxide, the titration on potentiometric titrator of ethanol standardized solution.
3) glycol ether: tetraethylene glycol dimethyl ether is interior mark, and sample is through measuring on gas chromatographicanalyzer after the alcoholysis.
4) form and aspect: the pellet sample 135 ℃ handle 1 hour after the Gardner automatic colour difference meter measure.
In the inventive method, owing to use product to be catalyzer by titanium compound, phosphorus compound and polyol reaction, the inventor is surprised to find this catalyzer and can be dissolved in and becomes homogeneous system in the ethylene glycol, make polyester with this catalyzer, can obtain the polyester of good form and aspect, obtain better technical effect.
The invention will be further elaborated below by embodiment.
Embodiment
[embodiment 1]
The preparation of catalyst A
Add ethylene glycol 62 grams (1 mole) and titanium isopropylate 142 grams (0.5 mole) in the reactor that agitator, condenser and thermometer are housed, 80 ℃ were reacted 1 hour down, and the Virahol of generation is removed in underpressure distillation, obtains white powder I A.
In the reactor that agitator, condenser and thermometer are housed, add trimethyl phosphite 99 140 grams (1 mole) and ethylene glycol 300 grams, reacted 4 hours the colourless transparent liquid II A of generation at 160 ℃ down.
Reaction product II A is added dropwise among the reaction product I A, and reaction is 2 hours under 100 ℃ of temperature, obtains colourless transparent liquid, and adopting plasma emission spectrometry to test its titanium content is 4.6% (weight).
The preparation of polyester
Restrain terephthalic acids and 316 gram ethylene glycol and a certain amount of catalyst A (based on the amount of the polyester that generates with 500, the weight of titanium atom is 15PPm) the mixed slurry that is made into, join in the polymeric kettle, carry out esterification, esterification temperature is 230～255 ℃, pressure is 0.25MPa, discharges the water that reaction generates by rectifier unit.Reduce to normal pressure after esterification finishes, vacuumize and be decompressed to system pressure and be lower than 130Pa, temperature of reaction rises to 280 ℃ gradually simultaneously, when system reaction stopped reaction after reach required viscosity, afterwards reaction product is extruded with bar shaped continuously from the polymeric kettle bottom, cooling, pelletizing are for performance test.
Test result sees Table 1.
[embodiment 2]
The preparation of catalyst B
Add ethylene glycol 62 grams (1 mole) and titanium isopropylate 142 grams (0.5 mole) in the reactor that agitator, condenser and thermometer are housed, 80 ℃ were reacted 1 hour down, and the Virahol of generation is removed in underpressure distillation, obtains white powder I B.
In the reactor that agitator, condenser and thermometer are housed, add trimethyl phosphite 99 70 grams (0.5 mole) and ethylene glycol 300 grams, reacted 4 hours the colourless transparent liquid II B of generation at 160 ℃ down.
Reaction product II B is added dropwise among the reaction product I B, and reaction is 2 hours under 100 ℃ of temperature, obtains flaxen transparent liquid, and adopting plasma emission spectrometry to test its titanium content is 5.0% (weight).
The preparation of polyester
Prepare polyester by the method identical, adopt catalyst B as catalyzer (based on the amount of the polyester that generates, the weight of titanium atom is 15PPm) with embodiment 1.
Test result sees Table 1.
[embodiment 3]
The preparation of catalyzer C
In the reactor that agitator, condenser and thermometer are housed, add ethylene glycol 62 grams (1 mole) and titanium isopropylate 142 grams (0.5 mole), 80 ℃ were reacted 1 hour down, the Virahol of generation is removed in underpressure distillation, obtain white powder I C, in the reaction response device, add trimethyl phosphite 99 140 grams (1 mole) and ethylene glycol 300 grams again, reacted 3 hours down at 180 ℃, generate light yellow transparent liquid, adopting plasma emission spectrometry to test its titanium content is 4.4% (weight).
The preparation of polyester
Prepare polyester by the method identical, adopt catalyzer C as catalyzer (based on the amount of the polyester that generates, the weight of titanium atom is 15PPm) with embodiment 1.
Test result sees Table 1.
[embodiment 4]
The preparation of catalyzer D
Add ethylene glycol 62 grams (1 mole) and titanium isopropylate 142 grams (0.5 mole) in the reactor that agitator, condenser and thermometer are housed, 80 ℃ were reacted 1 hour down, and the Virahol of generation is removed in underpressure distillation, obtains white powder I D.
In the reactor that agitator, condenser and thermometer are housed, add triethyl phosphate 182 grams (1 mole) and ethylene glycol 300 grams, reacted 4 hours the colourless transparent liquid II D of generation at 160 ℃ down.
Reaction product II D is added dropwise among the reaction product I D, and reaction is 2 hours under 100 ℃ of temperature, obtains colourless transparent liquid, and adopting plasma emission spectrometry to test its titanium content is 4.2% (weight).
The preparation of polyester
Prepare polyester by the method identical, adopt catalyzer D as catalyzer (based on the amount of the polyester that generates, the weight of titanium atom is 15PPm) with embodiment 1.
Test result sees Table 1.
[embodiment 5]
The preparation of catalyzer E
Add ethylene glycol 62 grams (1 mole) and titanium isopropylate 142 grams (0.5 mole) in the reactor that agitator, condenser and thermometer are housed, 80 ℃ were reacted 1 hour down, and the Virahol of generation is removed in underpressure distillation, obtains white powder I E.
In the reactor that agitator, condenser and thermometer are housed, add triethyl phosphate 182 grams (1 mole) and ethylene glycol 21700 grams, reacted 4 hours the colourless transparent liquid II E of generation at 160 ℃ down.
Reaction product II E is added dropwise among the reaction product I E, and reaction is 2 hours under 100 ℃ of temperature, obtains colourless transparent liquid, and adopting plasma emission spectrometry to test its titanium content is 0.1% (weight).
The preparation of polyester
Prepare polyester by the method identical, adopt catalyzer E as catalyzer (based on the amount of the polyester that generates, the weight of titanium atom is 15PPm) with embodiment 1.
Test result sees Table 1.
[comparative example 1]
Adopt Sb (AC)
3As Preparation of Catalyst polyester (based on the amount of the polyester that generates, the weight of Sb atom is 200PPm), the results are shown in Table 1.
[comparative example 2]
The titanium catalyst c-94 that adopts Acordis company the results are shown in Table 1 as Preparation of Catalyst polyester (based on the amount of the polyester that generates, the weight of titanium atom is 15PPm).
Table 1
| Catalyzer | Metal content (PPm) | Esterification time (min) | Polymerization time (min) | Viscosity (dL/ gram) | The end carboxyl (mole/t) | Glycol ether (%) | L | a | b | |
| Embodiment 1 | Catalyst A | 15 | 80 | 65 | 0.635 | 88.0 | -2.20 | 5.7 | ||
| Embodiment 2 | Catalyst B | 15 | 80 | 63 | 0.639 | 87.8 | -2.15 | 6.7 | ||
| Embodiment 3 | Catalyzer C | 15 | 80 | 64 | 0.641 | 88.1 | -2.13 | 5.8 | ||
| Embodiment 4 | Catalyzer D | 15 | 80 | 66 | 0.640 | 88.3 | -2.20 | 5.6 | ||
| Embodiment 5 | Catalyzer E | 15 | 80 | 65 | 0.643 | 88.0 | -2.18 | 5.6 | ||
| Comparative example 1 | SbAc3 | 200 | 90 | 77 | 0.635 | 12.3 | 4.39 | 86.1 | -2.20 | 5.7 |
| Comparative example 2 | C-94 | 15 | 80 | 53 | 0.600 | 10.6 | 3.46 | 87.6 | -2.76 | 8.2 |
Claims (9)
1, a kind of method of producing polyester, with di-carboxylic acid and aklylene glycol is raw material, in the presence of titanium-containing catalyst, in temperature of reaction is 230～280 ℃, reaction pressure is to carry out esterification under normal pressure～0.5MPa condition, obtains prepolymer, is 250～320 ℃ in temperature of reaction then, reaction pressure is characterized in that for to get polyester product less than carrying out polycondensation under the vacuum condition of 150Pa titanium-containing catalyst comprises the reaction product of following material:
(a) have the titanium compound of following general formula:
Ti(OR)
4
R is the alkyl that is selected from 1～10 carbon atom;
(b) be selected from the phosphorus compound of phosphate compounds, phosphite ester compound or its mixture;
(c) be selected from polyvalent alcohol with 2～10 carbon atoms.
2,, it is characterized in that di-carboxylic acid is selected from least a in terephthalic acid, phthalic acid, m-phthalic acid, naphthalic acid, biphenyl dicarboxylic acid or the cyclohexane dicarboxylic acid according to the method for the described production polyester of claim 1; Aklylene glycol is selected from ethylene glycol, 1,3 propylene glycol, propylene glycol, 1, at least a in the 4-butyleneglycol.
3,, it is characterized in that the consumption of titanium-containing catalyst is counted 1～100PPm with the polyester amount that generates according to the method for the described production polyester of claim 1.
4,, it is characterized in that the consumption of titanium-containing catalyst is counted 1～40PPm with the polyester amount that generates according to the method for the described production polyester of claim 3.
5,, it is characterized in that titanium compound is selected from least a in metatitanic acid tetramethyl ester, tetraethyl titanate, metatitanic acid orthocarbonate, titanium isopropylate or the tetrabutyl titanate according to the method for the described production polyester of claim 1.
6,, it is characterized in that phosphate compounds is selected from least a in trimethyl phosphite 99, triethyl phosphate, tricresyl phosphate propyl ester, tricresyl phosphate isopropyl ester, tributyl phosphate or the triphenylphosphate according to the method for the described production polyester of claim 1; Phosphite ester compound is selected from least a in dimethylphosphite, diethyl phosphite, phosphorous acid dipropyl, diisopropyl phosphite, dibutyl phosphite or the phosphorous acid diphenyl ester.
7,, it is characterized in that polyvalent alcohol is selected from ethylene glycol, 1,2-propylene glycol, 1,3 propylene glycol, 1,4-butyleneglycol, 1, at least a in 6-hexylene glycol, glycerine, TriMethylolPropane(TMP) or the tetramethylolmethane according to the method for the described production polyester of claim 1.
8, according to the method for the described production polyester of claim 1, the mol ratio that it is characterized in that phosphorus compound and titanium compound is 0.5～10: 1.
9, according to the method for the described production polyester of claim 1, the mol ratio that it is characterized in that polyvalent alcohol and titanium compound is 1～800: 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005101102906A CN100554307C (en) | 2005-11-11 | 2005-11-11 | Produce the method for polyester |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005101102906A CN100554307C (en) | 2005-11-11 | 2005-11-11 | Produce the method for polyester |
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| Publication Number | Publication Date |
|---|---|
| CN1962719A true CN1962719A (en) | 2007-05-16 |
| CN100554307C CN100554307C (en) | 2009-10-28 |
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|---|---|---|---|
| CNB2005101102906A Active CN100554307C (en) | 2005-11-11 | 2005-11-11 | Produce the method for polyester |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101323661B (en) * | 2007-06-13 | 2011-04-27 | 中国石油化工股份有限公司 | Process for producing polyester |
| CN103074697A (en) * | 2013-01-04 | 2013-05-01 | 东华大学 | Melt direct spinning moderately strong polyster fiber and preparation method thereof |
| CN108976403A (en) * | 2018-08-08 | 2018-12-11 | 济南朝晖科技有限公司 | The preparation method of polyester |
-
2005
- 2005-11-11 CN CNB2005101102906A patent/CN100554307C/en active Active
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101323661B (en) * | 2007-06-13 | 2011-04-27 | 中国石油化工股份有限公司 | Process for producing polyester |
| CN103074697A (en) * | 2013-01-04 | 2013-05-01 | 东华大学 | Melt direct spinning moderately strong polyster fiber and preparation method thereof |
| CN103074697B (en) * | 2013-01-04 | 2015-02-25 | 东华大学 | Melt direct spinning moderately strong polyster fiber and preparation method thereof |
| CN108976403A (en) * | 2018-08-08 | 2018-12-11 | 济南朝晖科技有限公司 | The preparation method of polyester |
| CN108976403B (en) * | 2018-08-08 | 2021-01-12 | 济南朝晖科技有限公司 | Process for producing polyester |
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| Publication number | Publication date |
|---|---|
| CN100554307C (en) | 2009-10-28 |
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