CN102775380B - Process for preparing lactide through fixed acid method - Google Patents
Process for preparing lactide through fixed acid method Download PDFInfo
- Publication number
- CN102775380B CN102775380B CN201210289443.8A CN201210289443A CN102775380B CN 102775380 B CN102775380 B CN 102775380B CN 201210289443 A CN201210289443 A CN 201210289443A CN 102775380 B CN102775380 B CN 102775380B
- Authority
- CN
- China
- Prior art keywords
- lactide
- lactic acid
- rac
- reaction
- hours
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Heterocyclic Compounds That Contain Two Or More Ring Oxygen Atoms (AREA)
Abstract
The invention discloses a process for preparing lactide through a fixed acid method, which comprises the following steps: (1) gradually heating a hydroxy or polyhydroxy or polyamino compound with a boiling point of 250-550 DEG C and lactic acid from 90 DEG C to 160 DEG C within 1.5-3 hours in the presence of a catalyst at a pressure controlled to be 2-3.0 KPa, then regulating the pressure to 0.5-0.8 KPa and the temperature to 170-180 DEG C, and continuing to react for 5-10.0 hours to obtain a hydroxy or polyhydroxy or polyamino lactic acid low polymer with a high boiling point; and (2) at the temperature of 180-230 DEG C and the pressure of 0.4-0.8 KPa, performing cracking reaction on the hydroxy or polyhydroxy or polyamino lactic acid low polymer with a high boiling point, which is obtained in the step (1), to obtain lactide. Compared with the lactide preparation method reported in public, the process disclosed by the invention achieves higher purity and better yield.
Description
Technical field
The present invention relates to a kind of preparation method of rac-Lactide, be specifically related to the technique of fixed acid legal system for rac-Lactide.
Background technology
Poly(lactic acid) has higher physical strength because of it and excellent biocompatibility, biological degradability and Bioabsorbable are widely used in many key areas.Be often used as surgical sutures in medical field poly(lactic acid), controlled drug delivery system, orthopaedics fixes and tissue engineering bracket material; In daily field, it is often used as the added ingredients of makeup; At agriculture field, it is commonly used for wrapping material and agricultural mulching.In addition, there is chemical research Development institution quite a lot, in research, poly(lactic acid) is used for degradative plastics field in the world, in this, as one of outlet solving plastic waste pollution problem.
Rac-Lactide is the important source material of preparation poly(lactic acid) (Polylactic acid, PLA).The poly(lactic acid) of synthesis high molecule mass needs the rac-Lactide that chemical purity is very high.The current method preparing high purity rac-Lactide first prepares crude lactide, and then refining obtain high purity rac-Lactide.Concrete grammar is: in first stage and the oligomeric stage of reaction, lactated dehydration is generated lactic acid oligomer, then at the subordinate phase of reacting and depolymerization by lactic acid oligomer catalytic degradation at relatively high temperatures, obtain crude lactide.Obtained crude lactide is because needing to obtain highly purified rac-Lactide after 3-5 recrystallization purifying containing impurity such as lactic acid, lactic acid dimer, lactic acid tripolymers.Patent US5053522, CN101585827, CN101157680 etc. are to this has been detailed description.In addition, patent WO2005056509 reports a kind of technique adopting rectificating method refined lactide.
Simultaneously the existing ubiquitous problem of method preparing rac-Lactide is difficult to obtain higher yield and good purity, is embodied in following three aspects:
First, in the oligomeric stage, the molecular mass of lactic acid oligomer needs in suitable scope, be just adapted at next stage cracking generation rac-Lactide, and (patent US4983745 thinks that lactic acid oligomer relative molecular mass optimum range is 400-2000, more desirably 600-800; Patent US5801255 think suitable depolymerization be the lactic acid oligomer relative molecular mass of rac-Lactide at 400-2000, more desirably 1000-2000), all can affect higher or lower than suitable scope the yield that cracking generates rac-Lactide in various degree.Current viewpoint is thought must control temperature of reaction and the reaction times in oligomeric stage by the lactic acid oligomer wanting to obtain suitable molecular weight.Temperature of reaction will control at 120-150 DEG C specifically, and time in reaction times general control is 2-3 hour.Too high temperature of reaction all can promote being polymerized of lactic acid oligomer with the longer reaction times, forms the polymkeric substance that relative molecular mass is larger.That is in oligomerization stage, in order to obtain the lactic acid oligomer of suitable molecular weight, people cannot by raising temperature of reaction, extending the water that the method in reaction times removes lactated reaction generation, thus the transformation efficiency of lactic acid in oligomerization cannot be improved, also just cannot reduce the content of water and free lactic acid in reaction system.Together can leave reaction system with the rac-Lactide generated at depolymerization water and lactic acid, become the impurity remained in rac-Lactide.
The second, at depolymerization, in order to ensure the yield of rac-Lactide, reaction vacuum tightness needs to be less than 1KPa, and temperature of reaction needs to control at 220-240 DEG C, the yield of rac-Lactide all can be made to decline below or above this temperature range.Therefore in the final stage of lactic acid oligomer depolymerization, be difficult to the lactic acid dimer of further depolymerization, lactic acid tripolymer together can leave reaction system with the rac-Lactide generated under the depolymerisation conditions of high temperature, low vacuum, becomes the impurity remained in rac-Lactide.
3rd, in the purification phase of rac-Lactide, although use recrystallization method or rectificating method can purifying rac-Lactide, these two kinds of methods all Shortcomings.Use recrystallization method purifying rac-Lactide, usual crude lactide needs through 3-5 recrystallization, significantly reduce the yield of reaction, and the recrystallization of continuous several times also improves the cost of industrial-scale production rac-Lactide while improving rac-Lactide purity.Rectification method purifying rac-Lactide is that the steam product stream generated after lactic acid oligomer cracking is delivered to rectifying tower, utilizes water, lactic acid, rac-Lactide, lactic acid dimer, and the difference of lactic acid tripolymer boiling point realizes the purifying to rac-Lactide.But the method is very high to the requirement of conversion unit, add the production cost of rac-Lactide equally.
Summary of the invention
Technical problem to be solved by this invention is to provide the technique of a kind of novel fixed acid legal system for rac-Lactide.
For solving the problems of the technologies described above, thinking of the present invention is as follows:
(1) in order to control in the scope of suitable depolymerization by the relative molecular mass of lactic acid oligomer, contriver attempts, and introduces in structure and has the higher-boiling compound of hydroxyl or amino to control oligomeric stage lactic acid oligomer relative molecular mass.Concrete principle is: in reaction system, add the higher-boiling compound with hydroxyl or amino, utilizes its hydroxyl or carboxyl that is amino and lactic acid oligomer molecule to react, forms ester bond or peptide bond.So just can fix the carboxyl terminal of lactic acid oligomer molecule, the molecular weight of lactic acid oligomer sharply can not be increased in reaction process.Next just the molecular mass of lactic acid oligomer is controlled in the scope of suitable depolymerization by adjustment higher-boiling compound with the ratio of the molar weight of lactic acid material.The water that the method just can make full use of in reaction process and raise temperature of reaction, extending the reaction times generates to remove lactated reaction, reduce the content of water and free lactic acid in reaction system, in final reduction rac-Lactide, the content of water and lactic acid, improves the purity of rac-Lactide.
(2) final stage of lactic acid oligomer depolymerization, be difficult to the lactic acid dimer of further depolymerization, lactic acid tripolymer is fixed on the hydroxyl of the higher-boiling compound with hydroxyl or amino due to its carboxyl terminal, be difficult to together with the rac-Lactide generated, leave reaction system in the vacuum tightness being less than 1KPa under 220-250 DEG C of such cracking condition, thus decrease lactic acid dimer in resultant rac-Lactide, the trimerical content of lactic acid, improves the purity of rac-Lactide.
Concrete technical scheme is as follows:
Fixed acid legal system is for a technique for rac-Lactide, and it comprises the steps:
(1) be that the hydroxyl of 250 ~ 550 DEG C or poly-hydroxy or multiamino compound and lactic acid are under catalyzer existence condition by boiling point, control pressure is at 2 ~ 3.0KPa, 160 DEG C are warming up to gradually by 90 DEG C in 1.5 ~ 3h, regulate pressure to be 0.5 ~ 0.8KPa again, temperature is 170 ~ 180 DEG C and continues reaction 5 ~ 7h and obtain high boiling point hydroxyl or poly-hydroxy or polyamino lactic acid oligomer;
(2) high boiling point hydroxyl step (1) obtained or poly-hydroxy or polyamino lactic acid oligomer in 180 ~ 230 DEG C, under 0.4-0.8KPa condition, scission reaction obtains rac-Lactide.
In step (1), described boiling point is the hydroxyl of 250 ~ 550 DEG C or poly-hydroxy or multiamino compound is tetramethylolmethane, nucite, D-glucitol, Isosorbide-5-Nitrae-anhydrous sorbitol, Xylitol, D-wood sugar, D-R, D-ribose, D-Fructose, sucrose, '-bis (hydroxymethyl) biphenyl or 4-aminodiphenylamine.
In step (1), described lactic acid is D, Pfansteihl, Pfansteihl or D-ALPHA-Hydroxypropionic acid.
In step (1), described catalyzer is stannous octoate, zinc oxide, zinc acetate or tin protochloride.
In step (1), the mass ratio of catalyzer and lactic acid is 1:20 ~ 500.
In step (1), described boiling point is the hydroxyl of 250 ~ 550 DEG C or the mol ratio of poly-hydroxy or multiamino compound and lactic acid is 1:10 ~ 150.
In step (1), the number-average molecular weight scope of high boiling point hydroxyl or poly-hydroxy or polyamino lactic acid oligomer is 1000 ~ 13000.Wherein, the number-average molecular weight scope of each branch is 300 ~ 2200.
In step (1), the high boiling point hydroxyl prepared or poly-hydroxy or polyamino lactic acid oligomer contain following hydroxylactic acid oligomer chain end structure unit, and structural formula is as follows:
In step (2), the scission reaction time is 40min ~ 80min.
Beneficial effect: innovative point of the present invention is:
(1) by the ratio of the molar weight of the higher-boiling compound with lactic acid material in adjust structure with hydroxyl or amino, the suitableeest molecular weight needed for lactic acid oligomer depolymerization is controlled.
(2) in the final stage of depolymerization, fix lactic acid dimer and tripolymer by the higher-boiling compound in structure with hydroxyl or amino, improve the purity of rac-Lactide.
Embodiment
According to following embodiment, the present invention may be better understood.But those skilled in the art will readily understand, the content described by embodiment only for illustration of the present invention, and should can not limit the present invention described in detail in claims yet.
Embodiment 1
Add 100.0g 85wt%D being equipped with in churned mechanically three-necked bottle, the Pfansteihl aqueous solution is (containing 85g D, Pfansteihl, 0.944mol), 7.3g(0.0536mol) tetramethylolmethane and 2.0g zinc acetate, be placed in 90 DEG C of oil baths, be evacuated to 3.0KPa, maintain this vacuum state, in 2.0 hours, temperature is at the uniform velocity warming up to 160.0 DEG C by 90 DEG C, then vacuum tightness is risen to 0.5KPa, temperature rises to 180.0 DEG C, reaction obtains oligopolymer in 5.0 hours with this understanding, maintain vacuum tightness 0.5KPa, temperature rises to 230.0 DEG C gradually by 180.0 DEG C and carries out scission reaction, scission reaction total time is 40min, collection obtains 63.4g rac-Lactide, yield 93.2%.Analyze through high performance liquid chromatography normalization method, purity is 96.9%.
Embodiment 2
Add 100.0g 85wt%D being equipped with in churned mechanically three-necked bottle, the Pfansteihl aqueous solution is (containing 85g D, Pfansteihl, 0.944mol), 1.4g(0.00777mol) nucite and 0.50g zinc acetate, be placed in 90 DEG C of oil baths, be evacuated to 3.0KPa, maintain this vacuum state, 3.0 temperature is at the uniform velocity warming up to 160.0 DEG C by 90 DEG C in hour, then vacuum tightness is risen to 0.5KPa, temperature rises to 180.0 DEG C, reaction obtains oligopolymer in 5.0 hours with this understanding, maintain vacuum tightness 0.5KPa, temperature rises to 230.0 DEG C gradually by 180.0 DEG C and carries out scission reaction, scission reaction total time is 60min, collection obtains 63.54g rac-Lactide, yield 93.4%.Analyze through high performance liquid chromatography normalization method, purity is 97.3%.
Embodiment 3
Add 100.0g 85wt%D being equipped with in churned mechanically three-necked bottle, the Pfansteihl aqueous solution is (containing 85g D, Pfansteihl, 0.944mol), 4.8g(0.0292mol) 1, 4-anhydrates sorbyl alcohol and 2.2g zinc acetate, be placed in 90 DEG C of oil baths, be evacuated to 3.0KPa, maintain this vacuum state, in 2.0 hours, temperature is at the uniform velocity warming up to 160.0 DEG C by 90 DEG C, then vacuum tightness is risen to 0.5KPa, temperature rises to 180.0 DEG C, reaction obtains oligopolymer in 5.0 hours with this understanding, maintain vacuum tightness 0.5KPa, temperature rises to 230.0 DEG C gradually by 180.0 DEG C and carries out scission reaction, scission reaction total time is 80min, collection obtains 65.6g rac-Lactide, yield 96.4%.Analyze through high performance liquid chromatography normalization method, purity is 97.7%.
Embodiment 4
Add 100.0g 85wt%D being equipped with in churned mechanically three-necked bottle, the Pfansteihl aqueous solution is (containing 85g D, Pfansteihl, 0.944mol), 17.3g(0.0939mol) 4-aminodiphenylamine and 2.0g zinc oxide, be placed in 90 DEG C of oil baths, be evacuated to 3.0KPa, maintain this vacuum state, 3.0 temperature is at the uniform velocity warming up to 160.0 DEG C by 90 DEG C in hour, then vacuum tightness is risen to 0.5KPa, temperature rises to 180.0 DEG C, reaction obtains oligopolymer in 6.0 hours with this understanding, maintain vacuum tightness 0.5KPa, temperature rises to 230.0 DEG C gradually by 180.0 DEG C and carries out scission reaction, scission reaction total time is 80min, collection obtains 63.06g rac-Lactide, yield 92.7%.Analyze through high performance liquid chromatography normalization method, purity is 96.1%.
Embodiment 5
Add 100.0g 85wt%D being equipped with in churned mechanically three-necked bottle, the Pfansteihl aqueous solution is (containing 85g D, Pfansteihl, 0.944mol), 5.7g(0.0313mol) D-glucitol and 2.0g tin protochloride, be placed in 90 DEG C of oil baths, be evacuated to 3.0KPa, maintain this vacuum state, in 2.0 hours, temperature is at the uniform velocity warming up to 160.0 DEG C by 90 DEG C, then vacuum tightness is risen to 0.5KPa, temperature rises to 180.0 DEG C, reaction obtains oligopolymer in 5.0 hours with this understanding, maintain vacuum tightness 0.5KPa, temperature rises to 230.0 DEG C gradually by 180.0 DEG C and carries out scission reaction, scission reaction total time is 80min, collection obtains 64.5g rac-Lactide, yield 94.8%.Analyze through high performance liquid chromatography normalization method, purity is 93.5%.
Embodiment 6
Add 100.0g 85wt%D being equipped with in churned mechanically three-necked bottle, the Pfansteihl aqueous solution is (containing 85g D, Pfansteihl, 0.944mol), 6.0g(0.0394mol) Xylitol and 2.0g tin protochloride, be placed in 90 DEG C of oil baths, be evacuated to 3.0KPa, maintain this vacuum state, in 2.0 hours, temperature is at the uniform velocity warming up to 160.0 DEG C by 90 DEG C, then vacuum tightness is risen to 0.5KPa, temperature rises to 180.0 DEG C, reaction obtains oligopolymer in 6.0 hours with this understanding, maintain vacuum tightness 0.5KPa, temperature rises to 230.0 DEG C gradually by 180.0 DEG C and carries out scission reaction, scission reaction total time is 80min, collection obtains 63.8g rac-Lactide, yield 93.9%.Analyze through high performance liquid chromatography normalization method, purity is 98.6%.
Embodiment 7
Add 100.0g 85wt%D being equipped with in churned mechanically three-necked bottle, the Pfansteihl aqueous solution is (containing 85g D, Pfansteihl, 0.944mol), 5.5g(0.0366mol) D-wood sugar and 2.0g tin protochloride, be placed in 90 DEG C of oil baths, be evacuated to 3.0KPa, maintain this vacuum state, in 2.0 hours, temperature is at the uniform velocity warming up to 160.0 DEG C by 90 DEG C, then vacuum tightness is risen to 0.5KPa, temperature rises to 180.0 DEG C, reaction obtains oligopolymer in 5.0 hours with this understanding, maintain vacuum tightness 0.5KPa, temperature rises to 230.0 DEG C gradually by 180.0 DEG C and carries out scission reaction, scission reaction total time is 80min, collection obtains 62.9g rac-Lactide, yield 92.5%.Analyze through high performance liquid chromatography normalization method, purity is 93.8%.
Embodiment 8
Add 100.0g 85wt%D being equipped with in churned mechanically three-necked bottle, the Pfansteihl aqueous solution is (containing 85g D, Pfansteihl, 0.944mol), 5.5g(0.0366mol) D-R and 2.0g tin protochloride, be placed in 90 DEG C of oil baths, be evacuated to 3.0KPa, maintain this vacuum state, in 2.0 hours, temperature is at the uniform velocity warming up to 160.0 DEG C by 90 DEG C, then vacuum tightness is risen to 0.5KPa, temperature rises to 180.0 DEG C, reaction obtains oligopolymer in 5.0 hours with this understanding, maintain vacuum tightness 0.5KPa, temperature rises to 230.0 DEG C gradually by 180.0 DEG C and carries out scission reaction, scission reaction total time is 80min, collection obtains 64.9g rac-Lactide, yield 95.5%.Analyze through high performance liquid chromatography normalization method, purity is 95.1%.
Embodiment 9
Add 100.0g 85wt%D being equipped with in churned mechanically three-necked bottle, the Pfansteihl aqueous solution is (containing 85g D, Pfansteihl, 0.944mol), 5.5g(0.0366mol) D-ribose and 2.0g tin protochloride, be placed in 90 DEG C of oil baths, be evacuated to 3.0KPa, maintain this vacuum state, in 2.0 hours, temperature is at the uniform velocity warming up to 160.0 DEG C by 90 DEG C, then vacuum tightness is risen to 0.5KPa, temperature rises to 180.0 DEG C, reaction obtains oligopolymer in 5.0 hours with this understanding, maintain vacuum tightness 0.5KPa, temperature rises to 230.0 DEG C gradually by 180.0 DEG C and carries out scission reaction, scission reaction total time is 80min, collection obtains 61.9g rac-Lactide, yield 91.0%.Analyze through high performance liquid chromatography normalization method, purity is 92.7%.
Embodiment 10
Add 100.0g 85wt%D being equipped with in churned mechanically three-necked bottle, the Pfansteihl aqueous solution is (containing 85g D, Pfansteihl, 0.944mol), 7.0g(0.0388mol) D-Fructose and 2.0g tin protochloride, be placed in 90 DEG C of oil baths, be evacuated to 3.0KPa, maintain this vacuum state, in 2.0 hours, temperature is at the uniform velocity warming up to 160.0 DEG C by 90 DEG C, then vacuum tightness is risen to 0.5KPa, temperature rises to 180.0 DEG C, reaction obtains oligopolymer in 5.0 hours with this understanding, maintain vacuum tightness 0.5KPa, temperature rises to 230.0 DEG C gradually by 180.0 DEG C and carries out scission reaction, scission reaction total time is 60min, collection obtains 64.08g rac-Lactide, yield 94.2%.Analyze through high performance liquid chromatography normalization method, purity is 93.1%.
Embodiment 11
Add 100.0g 85wt%D being equipped with in churned mechanically three-necked bottle, the Pfansteihl aqueous solution is (containing 85g D, Pfansteihl, 0.944mol), 6.5g(0.019mol) sucrose and 2.0g tin protochloride, be placed in 90 DEG C of oil baths, be evacuated to 3.0KPa, maintain this vacuum state, in 2.0 hours, temperature is at the uniform velocity warming up to 160.0 DEG C by 90 DEG C, then vacuum tightness is risen to 0.5KPa, temperature rises to 180.0 DEG C, reaction obtains oligopolymer in 5.0 hours with this understanding, maintain vacuum tightness 0.5KPa, temperature rises to 230.0 DEG C gradually by 180.0 DEG C and carries out scission reaction, scission reaction total time is 60min, collection obtains 64.63g rac-Lactide, yield 95.0%.Analyze through high performance liquid chromatography normalization method, purity is 93.3%.
Embodiment 12
Add 100.0g 85wt%D being equipped with in churned mechanically three-necked bottle, the Pfansteihl aqueous solution is (containing 85g D, Pfansteihl, 0.944mol), 16.8g '-bis (hydroxymethyl) biphenyl (0.0784mol) and 1.5g stannous octoate, be placed in 90 DEG C of oil baths, be evacuated to 3.0KPa, maintain this vacuum state, in 1.5 hours, temperature is at the uniform velocity warming up to 160.0 DEG C by 90 DEG C, then vacuum tightness is risen to 0.5KPa, temperature rises to 180.0 DEG C, reaction obtains oligopolymer in 5.0 hours with this understanding, maintain vacuum tightness 0.5KPa, temperature rises to 230.0 DEG C gradually by 180.0 DEG C and carries out scission reaction, scission reaction total time is 60min, collection obtains 64.42g rac-Lactide, yield 94.7%.Analyze through high performance liquid chromatography normalization method, purity is 98.4%.
Claims (1)
1. fixed acid legal system is for a technique for rac-Lactide, it is characterized in that, it comprises the steps:
Add 100.0g85wt%D being equipped with in churned mechanically three-necked bottle, the Pfansteihl aqueous solution, 16.8g '-bis (hydroxymethyl) biphenyl and 1.5g stannous octoate, be placed in 90 DEG C of oil baths, be evacuated to 3.0KPa, maintain this vacuum state, in 1.5 hours, temperature is at the uniform velocity warming up to 160.0 DEG C by 90 DEG C, then vacuum tightness is risen to 0.5KPa, temperature rises to 180.0 DEG C, reaction obtains oligopolymer in 5.0 hours with this understanding, maintain vacuum tightness 0.5KPa, temperature rises to 230.0 DEG C gradually by 180.0 DEG C and carries out scission reaction, scission reaction total time is 60min, collection obtains 64.42g rac-Lactide, yield 94.7%, purity is 98.4%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210289443.8A CN102775380B (en) | 2012-08-14 | 2012-08-14 | Process for preparing lactide through fixed acid method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210289443.8A CN102775380B (en) | 2012-08-14 | 2012-08-14 | Process for preparing lactide through fixed acid method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102775380A CN102775380A (en) | 2012-11-14 |
| CN102775380B true CN102775380B (en) | 2014-12-31 |
Family
ID=47120513
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210289443.8A Active CN102775380B (en) | 2012-08-14 | 2012-08-14 | Process for preparing lactide through fixed acid method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102775380B (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107108873B (en) * | 2014-12-19 | 2020-08-18 | 三菱化学株式会社 | Polycarbonate resin |
| CN110105324A (en) * | 2019-06-10 | 2019-08-09 | 南京大学 | The method that zinc Isoocatanoate catalyzes and synthesizes lactide |
| CN110563695B (en) * | 2019-09-22 | 2020-07-21 | 苏州格里克莱新材料有限公司 | Preparation method of mixture of glycolide and lactide |
| CN111892571A (en) * | 2020-08-28 | 2020-11-06 | 浙江海正生物材料股份有限公司 | Method for preparing lactide |
| CN113416134B (en) * | 2021-07-27 | 2022-08-23 | 重庆大学 | Lactic acid oligomer and preparation method and application thereof |
| CN114315788A (en) * | 2021-12-29 | 2022-04-12 | 普立思生物科技有限公司 | Preparation method of lactide |
| CN114773310A (en) * | 2022-04-20 | 2022-07-22 | 长兴电子（苏州）有限公司 | Method for synthesizing optically pure lactide by composite catalysis method |
| CN115745947A (en) * | 2022-11-23 | 2023-03-07 | 华东理工大学 | Preparation method of L-lactide |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5053522A (en) * | 1987-03-19 | 1991-10-01 | Boehringer Ingelheim Kg | Process for the preparation of lactide |
| CN101108844A (en) * | 2007-07-10 | 2008-01-23 | 南京工业大学 | Method for manufacturing lactide with polyhydroxy lactic acid oligomer |
| WO2012007379A1 (en) * | 2010-07-14 | 2012-01-19 | Solvay Sa | Process for the manufacture of a cyclic diester of an alpha-hydroxyacid |
-
2012
- 2012-08-14 CN CN201210289443.8A patent/CN102775380B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5053522A (en) * | 1987-03-19 | 1991-10-01 | Boehringer Ingelheim Kg | Process for the preparation of lactide |
| CN101108844A (en) * | 2007-07-10 | 2008-01-23 | 南京工业大学 | Method for manufacturing lactide with polyhydroxy lactic acid oligomer |
| WO2012007379A1 (en) * | 2010-07-14 | 2012-01-19 | Solvay Sa | Process for the manufacture of a cyclic diester of an alpha-hydroxyacid |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102775380A (en) | 2012-11-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102775380B (en) | Process for preparing lactide through fixed acid method | |
| US8258317B2 (en) | Catalyst for direct conversion of esters of lactic acid to lactide and the method for producing lactide using the same | |
| CN105622567A (en) | Preparation method of high-yield glycolide | |
| AU2017238018A1 (en) | Acrylic acid, and methods of producing thereof | |
| CN111039918A (en) | Method for preparing D-lactide by one-step gas phase reaction | |
| GB2591038A (en) | Synthesis method and device for rapidly producing lactide at high yield | |
| CN113582965B (en) | Method for preparing lactide based on catalytic cracking of organic guanidine complex | |
| JP5679411B2 (en) | Method for producing polylactic acid | |
| CA2423727C (en) | Process for producing lactide and process for producing polylactic acid from fermented lactic acid employed as starting material | |
| CN102863420B (en) | Method for preparing medical lactide | |
| JP2013515164A (en) | Process for producing biodegradable polylactic acid for medical use by polycondensation from lactic acid catalyzed by creatinine | |
| WO2014173047A1 (en) | Technological method for synthesizing optical pure l-/d-lactide by using biomass organic guanidine catalysis method | |
| CN110128397B (en) | Preparation method of high-purity lactide | |
| CN105315152A (en) | Preparation method polyglycolic acid oligomer | |
| CN101585827A (en) | Method for preparing lactide with high yield | |
| CN101108844B (en) | Method for manufacturing lactide with polyhydroxy lactic acid oligomer | |
| CN109134230B (en) | Method for preparing D-configuration excessive lactic acid by catalytic conversion of xylose, glucose, xylan, microcrystalline cellulose and corn straw | |
| Wang et al. | Preparation of high purity lactide using a high-boiling-point alcohol immobilization method | |
| CN113956230A (en) | Synthesis method of high-purity lactide | |
| US20100125110A1 (en) | Lactic acid oligomer and method for producing the same | |
| CN111004373A (en) | Preparation method of medical multi-arm polycaprolactone | |
| CN104497280B (en) | A kind of preparation method of PGA | |
| CN103864999B (en) | Preparation method for maleic anhydride-modified poly(lactic-co-glycolic acid) copolymer | |
| CN100417651C (en) | Method for catalytic synthesis of lactide from lactic acid | |
| KR101183982B1 (en) | Process for preparing lactide and polylactide from Lactic acid fermentation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C53 | Correction of patent for invention or patent application | ||
| CB03 | Change of inventor or designer information |
Inventor after: Tang Shigui Inventor after: Guo Kai Inventor after: Jiang Yunchen Inventor after: Gan Haifeng Inventor after: Wei Ping Inventor after: Sun Yanlong Inventor before: Tang Shigui Inventor before: Guo Kai Inventor before: Gan Haifeng Inventor before: Wei Ping Inventor before: Jiang Yunchen Inventor before: Sun Yanlong |
|
| COR | Change of bibliographic data |
Free format text: CORRECT: INVENTOR; FROM: TANG SHIGUI GUO KAI GAN HAIFENG WEI PING JIANG YUNCHEN SUN YANLONG TO: TANG SHIGUI GUO KAI JIANG YUNCHEN GAN HAIFENG WEI PING SUN YANLONG |
|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C41 | Transfer of patent application or patent right or utility model | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20160922 Address after: Spark Road high tech Development Zone Nanjing city Jiangsu province 210032 No. 10 Dingye gestos biological building block A room 1014 Patentee after: Nanjing Hi Tech Institute of Biotechnology Research Co Ltd Address before: 210009 Nanjing City, Jiangsu Province, the new model road No. 5 Patentee before: Nanjing University of Technology |