CN1049905C - Method for copolymerization of internal ester (or lactide) and polyether glycol - Google Patents
Method for copolymerization of internal ester (or lactide) and polyether glycol Download PDFInfo
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- CN1049905C CN1049905C CN94111738A CN94111738A CN1049905C CN 1049905 C CN1049905 C CN 1049905C CN 94111738 A CN94111738 A CN 94111738A CN 94111738 A CN94111738 A CN 94111738A CN 1049905 C CN1049905 C CN 1049905C
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- lactide
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Abstract
The present invention uses triisobutylaluminium as a catalyst, and under the protection of nitrogen, at 60 to 220 DEG C, lactone (or cyclic diester) is initiated to carry out main body or solution copolymerization with polyether glycol. The lactone suitable for the present invention mainly comprises lactic lactide, glycolide, epsilon-caprolactone, delta-valerolactone, beta-butyrolactone, etc., and suitable polyether glycol mainly comprises polyethylene glycol, polypropylene, polytetramethylene glycol, etc. A biologically-soluble block polymer of polylactic acid and the polyethylene glycol of the present invention has good mechanical strength and good biocompatibility.
Description
The present invention relates to a kind of lactone or lactide and polyether glycol is catalyzer with the triisobutyl aluminium, carries out the method that body or solution copolymerization are produced three blocks (ABA block) multipolymer.
The homopolymer of lactone or lactide or multipolymer, have nontoxic, biocompatibility well reaches characteristics such as biodegradable, be widely used as biodegradable material, for example be used for many medicament slow release systems and make solid support material, degradation cycle can be controlled in one month to several years, as is used for contraception, anticancer, the slow-released carrier of medicines such as hormone; Be used as the interior propping material of body as not needing the bone clamping plate of second operation, surgical sewing thread, bone restoration, nerve regeneration conduit etc.Particularly the homopolymerization of newborn lactide and copolymerization product are the good biological degradable materials that can be used for human body of generally acknowledging both at home and abroad at present.In order to increase the wetting ability of lactone homopolymerization product, flexibility is normally introduced hydrophilic, nontoxic polyether segment in the lactone segment, like this can be by regulating hydrophilic/hydrophobic segment ratio in the macromolecular chain, reach the purpose of control material degradation speed, the research report is a lot of both at home and abroad.
R.D.Lundberg etc. (Journal of Polymer Science Part A-1,1969,7:2915) report can make the effective polymerization of 6-caprolactone with dibutyl zinc or triisobutyl aluminium, but the polymerization of other lactone such as newborn lactide is reported.An aromatic plant metioned in ancient books in Shen etc. (chemical journal, 1990,48:686), make the polymerization in toluene solution of newborn lactide with rare earth compound-triisobutyl aluminium-water coordination catalyst, the general molecular weight of products therefrom is lower, is up to 70,000.USP4,438,253 disclose the preparation method of poly-glycollide (PGA)/polyoxyethylene glycol (PEG) segmented copolymer, this method need at first prepare the glycollide homopolymer, add chainextender (aromatic orthocar-bonate chain extender) then, under vacuum condition, 235 ℃ with polyether glycol reaction 30 minutes.Not only there is the chain extending reaction product in gained multipolymer complicated component under the high temperature, and has the ester exchange offspring of PGA and PEG.EP0295,055 with Sb
2O
3And H
3PO
4Be catalyzer, poly(lactic acid)/polyoxyethylene glycol segmented copolymer is produced in direct and polyoxyethylene glycol polycondensation by lactic acid, and this method polymerization time needs 36 hours, and polymerization temperature is up to 200 ℃, and maximum vacuum requires 666 pascals.Report stannous octoates such as Zhu Kangjie be Preparation of Catalyst polylactic acid-polyglycol triblock copolymer (the polymer journal, 1989,4:258), polymerizing condition is at N
2Under the protection, 180 ℃ were reacted 10 hours.This method temperature of reaction is higher, does not react below 150 ℃, and the reaction times is longer, molecular weight of product not high (generally below 10,000).
Deng Xianmo etc. (J.Polym.Sci., Part C:Polym.Lett., 190,28:411) make poly(lactic acid)/polyoxyethylene glycol triblock copolymer, but molecular weight of product is lower with some cationic catalysts and stannous octoate.Yoshiharu Kimura etc. (Polymer, 1989,30:1342) with Me
3Al-H
2O is a catalyzer, and 13330 pascals, 150 ℃ of following mass polymerizations 6 hours make L-poly(lactic acid)-polypropylene glycol triblock copolymer, yield lower (＜90%); Hans R.Kricheldorf etc. (Makromol.Chem., 1993,194:175) adopting stannous octoate etc. is catalyzer, at 150 ℃, N
2Under the protection, mass polymerization makes L-poly(lactic acid)/polyethyleneglycol block copolymer.
JP63-69, the polyethers of 825 (1988) report employing two ends carbonylations and newborn lactide are with Et
2Zn is a catalyzer, copolymerization in 80 ℃ of toluene solutions, and the product that makes has certain physical strength.This method needs preparation carbonylation polyethers earlier, and final product need be used Ac
2O carries out acetylize.
Based on the shortcoming of prior art, the objective of the invention is to seek the catalyzer that a kind of activity is high, toxicity is low, to shorten polymerization process, simplify the operation, improve polymerization technique, make it to make high-molecular weight polymer; Simultaneously can regulate molecular weight on request, make the polymerisate of certain molecular weight.
The objective of the invention is to reach by the following method:
With lactone or lactide and polyether glycol, in the presence of the triisobutyl Al catalysts, carry out body or solution copolymerization is produced triblock copolymer, the consumption that molecular weight can be by the comonomer polyether glycol and/or add conditioning agent and regulate.The gained multipolymer is behind the dissolution with solvents reprecipitation, and vacuum-drying makes product.
The structure of used lactone of the present invention (I) or lactide (II) is:
N=3-5 wherein, h, m=1 or 2; R is H or alkyl, with H or CH
3-for well.Lactone or lactide commonly used have ε-caprolactone, beta-butyrolactone, δ-Wu Neizhi, glycollide or newborn lactide etc.
The comonomer polyether glycol that the present invention is suitable for mainly is a polyoxyethylene glycol, polypropylene glycol or polytetramethylene glycol, the molecular weight of polyether glycol generally adopts below 20,000, and being advisable below 10,000, general is the polyether glycol of 1-2 ten thousand with molecular weight when requiring multipolymer intensity higher.The comonomer consumption is generally the 0-30% (weight) of total monomer weight.
The molecular weight regulator that the present invention uses is Fatty Alcohol(C12-C14 and C12-C18), generally adopts the Fatty Alcohol(C12-C14 and C12-C18) of 12-24 carbon atom, with the Fatty Alcohol(C12-C14 and C12-C18) of 12-18 carbon atom for well, as dodecanol, Stearyl alcohol.The conditioning agent consumption is advisable with the 0-2.5% (weight) of total monomer weight.
The triisobutyl aluminium that uses among the present invention (Al (iBu)
3) catalyzer is general is made into the solution use of 0.1-1M concentration with solvent.Catalyst levels is many more, reacts fast more, and catalyst levels is advisable with the 0.02-1.0% of total monomer weight.This catalyzer toxicity after hydrolysis or alcoholysis is little, activity is high, consumption is few, easy to use.
Solvent for use is advisable with the solvent of the fine dissolve polymer of energy during solution polymerization.The present invention to be selecting for use aromatic hydrocarbons and halogenated alkane for well, and commonly used have toluene, dimethylbenzene, trichloromethane, a methylene dichloride etc.Solvent needs drying to handle before use, adopts sodium Metal 99.5 or hydrolith to have distillation purifying down.Solvent load is too little, can not finely dissolve the polymkeric substance that is generated, and causes waste too much, generally adopts solvent: monomer=0-9 (volume): 1 (weight).
Before catalyzer added, air need be used inert gas replacement in the reactor, reacted in inert atmosphere then, and suitable rare gas element has nitrogen, argon gas etc.Being reflected at normal pressure carries out.Temperature of reaction generally is controlled at 60-220 ℃, with 110-160 ℃ for well, under this temperature, speed of response is suitable, the product color is more shallow.
Polymerization is finished, and product needs through reprecipitation, and the homopolymerization or the multipolymer of D, L-breast lactide are to precipitate in distilled water after being dissolved in acetone; The homopolymerization or the multipolymer of L-breast lactide or other lactone are to precipitate in methyl alcohol after being dissolved in chloroform.
The gained all limiting viscosity (η) of (being total to) polymers is measured: the homopolymerization or the multipolymer of D, L-breast lactide are to be dissolved in the tetrahydrofuran (THF), 37 ° of mensuration, and the homopolymerization or the multipolymer of L-breast lactide or other lactone lactide are to be dissolved in the chloroform, 25 ℃ of mensuration.
D, the viscosity-average molecular weight of homopolymerization of L-poly(lactic acid) or multipolymer (M η) is pressed following formula (Wise, Douald; Et.al., Drug Carriors Biol.Med., 1979,237) calculate:
〔η〕＝1.04×10
-4Mη
0.75
The poly-D that the inventive method makes, L-breast lactide molecular weight can be up to 50-60 ten thousand.
Embodiment 1
Adding 25g D in the 100ml reaction flask that charged magnetic stirs, L-breast lactide, air in the logical nitrogen replacement(metathesis)reaction bottle is warming up to 140 ℃ under nitrogen atmosphere, treat D, after L-breast lactide all melts, is cooled to 130 ℃, adds Al (i-Bu)
3Toluene solution (concentration 0.36M) 0.13ml, stir after 5 minutes, newborn lactide can not flow, and reacts 40 minutes again, the cooling stopped reaction adds acetone solution, in distilled water, precipitate, after the vacuum-drying product 22g.Polymkeric substance is dissolved in the tetrahydrofuran (THF), and 37 ℃ record limiting viscosity (η) and are 2.01dl/g (M η=51.8 * 10
4).
Embodiment 2
Experimental installation, operation adds D with embodiment 1 in reaction flask, L-breast lactide 60.5g, stearyl alcohol 0.09g, logical nitrogen, be warming up to 140 ℃ of fusings to be crystallized after, be cooled to 130 ℃, add Al (i-Bu)
3Toluene solution (concentration 0.36M) 0.37ml, stir after 5 minutes, newborn lactide does not flow, and continues constant temperature 40 minutes, the cooling stopped reaction, reprecipitation gets product 56g, records (η) and is 1.39dl/g (M η=31.7 * 10
4).
Embodiment 3
Device and operation add D with embodiment 1 in reaction flask, L-breast lactide 23.75g, and polyoxyethylene glycol (M=4000) 1.25g, logical nitrogen is warming up to 160 ℃, adds Al (i-Bu) after the fusing to be crystallized
3Toluene solution (0.36M) 0.45ml, stirring reaction 35 minutes, the cooling, reprecipitation gets product 23.5g.Multipolymer is made into tetrahydrofuran solution, and 37 ℃ record (η) and are 0.51dl/g[M η=8.3 * 10
4],
1HNMR records and contains PEG4.6% in the multipolymer.
Embodiment 4
Device, operation adds D with embodiment 3 in reaction flask, L-breast lactide 22.5g, polyoxyethylene glycol (M=4000) 2.5g, logical nitrogen is warming up to 160 ℃ of fusing to be crystallized backs and adds Al (i-Bu)
3Toluene solution (concentration 0.36M) 0.36ml, reacted 34 minutes, cooling behind the reprecipitation product 22.5g, (η) is 0.32dl/g (M η=4.5 * 10
4),
1HNMR records and contains PEG9.1% in the multipolymer.
Embodiment 5
Device, operation adds D with embodiment 3 in reaction flask, L-breast lactide 35g, PEG (M=6000) 15g, logical nitrogen is warming up to 135 ℃ of fusing to be crystallized backs and adds Al (i-Bu)
3Toluene solution (concentration 0.36M) 0.7ml, stirred 35 minutes, cooling, behind the reprecipitation product 44.6g, record (η) for 0.18dl/g (M η=2.1 * 10
4),
1HNMR records and contains PEG27.8% in the multipolymer.
Embodiment 6
Device, operation add D, L-breast lactide 28.5g, polyoxyethylene glycol (M=1500) 3.0g, lauryl alcohol 0.25g with embodiment 3 in reaction flask.Logical nitrogen, be warming up to 130 ℃ of fusings to be crystallized after, add Al (i-Bu)
3Toluene solution (concentration 0.36M) 0.49ml, stirring reaction 1 hour, cooling, reprecipitation gets product 25.8g, measuring (η) is 0.15dl/g (M η=1.6 * 10
4),
1HNMR measures in the multipolymer and contains PEG11%.
Embodiment 7
Device adds D with embodiment 3 in reaction flask, L-breast lactide 7.2g, and PEG (M=6000) 0.8g vacuumized 1 hour at 80 °, added 27ml toluene under the N gas shiled, stirred, and was warming up to 120 ℃, added Al (i-Bu)
3Toluene solution (concentration 0.36M) 0.22ml.Reacted 1.5 hours, and got product 6.8g, record (η) and be 0.54dl/g (M η=8.9 * 10 with the methyl alcohol reprecipitation
4),
1HNMR measures in the multipolymer and contains PEG10.6%.
Embodiment 8
In the 50ml reaction flask, add L-breast lactide 9.0g, PEG (M=6000) 1.0g, logical nitrogen is warming up to 125 ℃, adds Al (i-Bu) under the induction stirring
3Toluene solution (0.36M) 0.1ml, react 1.5 hours postcooling, add chloroform dissolving back and in methyl alcohol, precipitate, after the vacuum-drying product 8.9g.In chloroformic solution, 25 ℃ record (η) is 1.61dl/g,
1HNMR records and contains PEG12.3% in the multipolymer.
Embodiment 9
Device, operation add 6-caprolactone 45g with embodiment 3 in reaction flask, polyoxyethylene glycol (M=4000) 5.0g, and logical nitrogen is warming up to 85 ℃, stirs to add Al (i-Bu)
3Toluene solution 2.1ml (concentration 0.36M). solidify immediately, react 30 minutes stopped reaction,, get the 48.9g product after the vacuum-drying with chloroform dissolving, methanol extraction.
1HNMR measures PEG content 8.8% in the multipolymer.
Embodiment 10
Device adds D with embodiment 3 in the 50ml reaction flask, L-breast lactide 10g, and polytetramethylene glycol (M=2900) 1.0g, logical nitrogen is warming up to 160 ℃, stirs to add Al (i-Bu) down
3Toluene solution (0.36M) 0.1ml reacts 30 minutes stopped reaction, cooling.The product acetone solution filters, and with the distilled water precipitation, gets product 9.8g, warp after the vacuum-drying then
1Polytetramethylene glycol content is 9.4% in the HNMR mensuration multipolymer.
Products therefrom of the present invention is its physical and mechanical properties such as following table after testing:
| Polymkeric substance | PEG4000 consumption (%) | Polymkeric substance *Viscosity (μ) | Second-order transition temperature Tg ℃ | Yielding stress (MPa) | Young's modulus (GPa) | The disconnected elongation % that attacks |
| Embodiment 2 | 0 | 1.39 | 59 | 108.8 | 2.84 | 136.0 |
| Embodiment 3 | 5 | 0.51 | 44 | 40.2 | 0.98 | 306.0 |
| Embodiment 4 | 10 | 0.32 | 36 | 13.7 | 0.03 | 650.0 |
*: (η) measures in the tetrahydrofuran (THF) at 37 ℃.
The result is as follows in the biomedicine evaluation of product of the present invention (sample: homopolymer is embodiment 2, and multipolymer is embodiment 3): one, acute toxicity test
1. four of two kinds of materials kinds of vat liquors are nontoxic.
2. material degradation liquid: poly(lactic acid) mouse peritoneal injection LD
50Be 2.1g/kg, multipolymer is 1.8g/kg.Two, pyrogen testing: two kinds of material vat liquors do not have the pyrogeneous substance effect.Three, hemolytic test:
1. two kinds of material vat liquors do not cause haemolysis.
2. material degradation liquid: PLA concentration is 440mg/ml, does not cause haemolysis when multipolymer is 360mg/ml.Four, intracutaneous irritant test
1. two kinds of material vat liquor nonirritants.
2. degradation solution: poly(lactic acid) and copolymer concentration are respectively 0.17% and 0.14% o'clock nonirritant.Five, eye conjunctiva irritant test:
1. two kinds of material vat liquor nonirritants.
2. degradation solution: poly(lactic acid) and copolymer concentration are respectively 0.084% and at 0.07% o'clock, no eye irritation.Six, hypersensitive test:
1. two kinds of material vat liquors do not have anaphylaxis.
2. two kinds of material degradation liquid, no sensitization.Seven, cell toxicity test: two kinds of material degradation liquid no cytotoxicities.Eight, micronucleus test: two kinds of material degradation liquid are pressed LD
50 
Dosage successive administration 30 times, poly(lactic acid) are 4.8 ‰, and multipolymer is that 3.4 ‰ results do not have mutagenesis.Nine, Salmonella reversion test: poly-lactic acid material is negative.Ten, subchronic toxicity test: two kinds of material degradation liquid successive administrations nontoxicity influence in 30 days.11, in-vivo embed test: 3 days-9 months, two kinds of material structure consistencies were good.12, external degradation test: in the time of 90 days, poly(lactic acid) and molecular weight of copolymer forfeiture are respectively 97.70% and 71.12%; In the time of 200 days, weight loss is respectively 55.37% and 46.23%.Ten, vivo degradation test: 168 days poly(lactic acid) and molecular weight of copolymer forfeiture are respectively 98.0% and 98.15%; Weight loss is respectively 76.32% and 84.85%.
Method of the present invention is because catalyst activity height, the toxicity used are little, speed of response is fast, can make the very high product of molecular weight; Simultaneously also can be as requested by monomeric consumption and/or adding conditioning agent carry out molecular-weight adjusting altogether; Polymerization technique is simple, and easy handling is reflected under the normal pressure and carries out, the monomer conversion height, and can select body or solution polymerization process according to actual needs; Biodegradable polylactic acid-the polyethyleneglycol block copolymer that makes has excellent mechanical intensity and biocompatibility.
Claims (7)
1. lactone or lactide and polyether glycol carry out the method for body or solution copolymerization, it is characterized in that with the triisobutyl aluminium being catalyzer.
2. according to the described process for copolymerization of claim 1, it is characterized in that the structural formula of lactone (I) or lactide (II) is:
Wherein n is 3-5, and R is H or alkyl, and h, m are 1 or 2.
3. according to the described process for copolymerization of claim 1, it is characterized in that used polyether glycol is a polyoxyethylene glycol, polypropylene glycol or polytetramethylene glycol, molecular weight adopts below 20,000.
4. according to the described process for copolymerization of one of claim 1-3, the consumption that it is characterized in that polyether glycol is the 0-30% (weight) of total monomer weight.
5. according to the described process for copolymerization of claim 1, it is characterized in that catalyst levels is 0.02-1% (in a total monomer weight).
6. according to the described process for copolymerization of claim 1, it is characterized in that solvent for use is aromatic hydrocarbons or halogenated alkane.
7. according to claim 1 or 6 described process for copolymerization, it is characterized in that solvent load is a monomer: solvent=1 (weight): 0-9 (volume).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN94111738A CN1049905C (en) | 1994-05-03 | 1994-05-03 | Method for copolymerization of internal ester (or lactide) and polyether glycol |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN94111738A CN1049905C (en) | 1994-05-03 | 1994-05-03 | Method for copolymerization of internal ester (or lactide) and polyether glycol |
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| Publication Number | Publication Date |
|---|---|
| CN1111253A CN1111253A (en) | 1995-11-08 |
| CN1049905C true CN1049905C (en) | 2000-03-01 |
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|---|---|---|---|
| CN94111738A Expired - Lifetime CN1049905C (en) | 1994-05-03 | 1994-05-03 | Method for copolymerization of internal ester (or lactide) and polyether glycol |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1305928C (en) * | 2003-10-27 | 2007-03-21 | 启东致远生物科技有限公司 | Method for preparing biodegradable material |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100424111C (en) * | 2004-03-25 | 2008-10-08 | 上海同杰良生物材料有限公司 | Method for preparing high-branched poly lactic acid through bulk polymerization |
| CN101343354B (en) * | 2008-08-29 | 2011-05-04 | 胡权 | Poly-lactide, poly-glycolide and preparation for copolymer of the same |
| CN110117359B (en) * | 2018-02-05 | 2021-12-21 | 青岛博远高分子材料研究院有限公司 | Polyether-b-poly (gamma-butyrolactone) block copolymer and preparation method thereof |
| WO2023064210A1 (en) * | 2021-10-15 | 2023-04-20 | Croda, Inc. | Polylactic acid and polyether compounds |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH118226A (en) * | 1997-06-17 | 1999-01-12 | Oki Electric Ind Co Ltd | Cleaning of semiconductor substrate surface and apparatus therefor |
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1994
- 1994-05-03 CN CN94111738A patent/CN1049905C/en not_active Expired - Lifetime
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH118226A (en) * | 1997-06-17 | 1999-01-12 | Oki Electric Ind Co Ltd | Cleaning of semiconductor substrate surface and apparatus therefor |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1305928C (en) * | 2003-10-27 | 2007-03-21 | 启东致远生物科技有限公司 | Method for preparing biodegradable material |
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| CN1111253A (en) | 1995-11-08 |
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