CN107033193B - A kind of schiff bases iron compound, preparation method and its application as catalyst - Google Patents
A kind of schiff bases iron compound, preparation method and its application as catalyst Download PDFInfo
- Publication number
- CN107033193B CN107033193B CN201710427791.XA CN201710427791A CN107033193B CN 107033193 B CN107033193 B CN 107033193B CN 201710427791 A CN201710427791 A CN 201710427791A CN 107033193 B CN107033193 B CN 107033193B
- Authority
- CN
- China
- Prior art keywords
- formula
- present
- structure shown
- preparation
- schiff bases
- 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
- 239000002262 Schiff base Substances 0.000 title claims abstract description 139
- -1 schiff bases iron compound Chemical class 0.000 title claims abstract description 111
- 239000003054 catalyst Substances 0.000 title claims abstract description 47
- 238000002360 preparation method Methods 0.000 title claims abstract description 45
- 229920000747 poly(lactic acid) Polymers 0.000 claims abstract description 106
- 239000004626 polylactic acid Substances 0.000 claims abstract description 106
- JJTUDXZGHPGLLC-UHFFFAOYSA-N lactide Chemical compound CC1OC(=O)C(C)OC1=O JJTUDXZGHPGLLC-UHFFFAOYSA-N 0.000 claims abstract description 87
- 150000004753 Schiff bases Chemical class 0.000 claims abstract description 61
- 238000007151 ring opening polymerisation reaction Methods 0.000 claims abstract description 59
- 229920001610 polycaprolactone Polymers 0.000 claims abstract description 39
- 239000004632 polycaprolactone Substances 0.000 claims abstract description 39
- PAPBSGBWRJIAAV-UHFFFAOYSA-N ε-Caprolactone Chemical compound O=C1CCCCCO1 PAPBSGBWRJIAAV-UHFFFAOYSA-N 0.000 claims abstract description 28
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 22
- 125000001449 isopropyl group Chemical group [H]C([H])([H])C([H])(*)C([H])([H])[H] 0.000 claims abstract description 19
- 229910052742 iron Inorganic materials 0.000 claims abstract description 12
- 239000002904 solvent Substances 0.000 claims description 42
- 239000003446 ligand Substances 0.000 claims description 40
- 238000006243 chemical reaction Methods 0.000 claims description 37
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 claims description 18
- 240000000203 Salix gracilistyla Species 0.000 claims description 17
- 238000006482 condensation reaction Methods 0.000 claims description 16
- 238000010992 reflux Methods 0.000 claims description 16
- GOOHAUXETOMSMM-UHFFFAOYSA-N Propylene oxide Chemical group CC1CO1 GOOHAUXETOMSMM-UHFFFAOYSA-N 0.000 claims description 14
- 125000000999 tert-butyl group Chemical group [H]C([H])([H])C(*)(C([H])([H])[H])C([H])([H])[H] 0.000 claims description 11
- 150000002506 iron compounds Chemical class 0.000 claims description 2
- 150000001875 compounds Chemical class 0.000 claims 2
- 125000003368 amide group Chemical group 0.000 claims 1
- 229910052736 halogen Inorganic materials 0.000 abstract description 17
- 150000002367 halogens Chemical class 0.000 abstract description 17
- 125000000217 alkyl group Chemical group 0.000 abstract description 15
- 238000000034 method Methods 0.000 abstract description 13
- 230000003197 catalytic effect Effects 0.000 abstract description 7
- 229910052751 metal Inorganic materials 0.000 abstract description 4
- 239000002184 metal Substances 0.000 abstract description 4
- 239000000243 solution Substances 0.000 description 55
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 51
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 42
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 description 30
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical compound ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 description 28
- 229920000642 polymer Polymers 0.000 description 27
- 238000004458 analytical method Methods 0.000 description 22
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 description 21
- 235000019441 ethanol Nutrition 0.000 description 21
- 239000004793 Polystyrene Substances 0.000 description 20
- 238000005227 gel permeation chromatography Methods 0.000 description 20
- 239000011259 mixed solution Substances 0.000 description 20
- 229920002223 polystyrene Polymers 0.000 description 20
- 239000013558 reference substance Substances 0.000 description 20
- 238000012869 ethanol precipitation Methods 0.000 description 12
- 238000001953 recrystallisation Methods 0.000 description 10
- 125000004429 atom Chemical group 0.000 description 9
- 238000000921 elemental analysis Methods 0.000 description 9
- 238000006116 polymerization reaction Methods 0.000 description 9
- PIICEJLVQHRZGT-UHFFFAOYSA-N Ethylenediamine Chemical compound NCCN PIICEJLVQHRZGT-UHFFFAOYSA-N 0.000 description 8
- 239000007795 chemical reaction product Substances 0.000 description 8
- RRIQVLZDOZPJTH-UHFFFAOYSA-N 3,5-di-tert-butyl-2-hydroxybenzaldehyde Chemical compound CC(C)(C)C1=CC(C=O)=C(O)C(C(C)(C)C)=C1 RRIQVLZDOZPJTH-UHFFFAOYSA-N 0.000 description 7
- 239000011541 reaction mixture Substances 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 238000001914 filtration Methods 0.000 description 6
- 239000011261 inert gas Substances 0.000 description 6
- JVTAAEKCZFNVCJ-UHFFFAOYSA-N lactic acid Chemical compound CC(O)C(O)=O JVTAAEKCZFNVCJ-UHFFFAOYSA-N 0.000 description 6
- 238000003756 stirring Methods 0.000 description 6
- 238000005481 NMR spectroscopy Methods 0.000 description 5
- 239000002253 acid Substances 0.000 description 5
- 238000006555 catalytic reaction Methods 0.000 description 5
- 229910052801 chlorine Inorganic materials 0.000 description 5
- 239000000460 chlorine Substances 0.000 description 5
- 239000006071 cream Substances 0.000 description 5
- 239000000178 monomer Substances 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- AOHJOMMDDJHIJH-UHFFFAOYSA-N propylenediamine Chemical compound CC(N)CN AOHJOMMDDJHIJH-UHFFFAOYSA-N 0.000 description 5
- 150000001299 aldehydes Chemical class 0.000 description 4
- 239000003513 alkali Substances 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 4
- 125000004432 carbon atom Chemical group C* 0.000 description 4
- 125000001309 chloro group Chemical group Cl* 0.000 description 4
- 238000004090 dissolution Methods 0.000 description 4
- 238000001035 drying Methods 0.000 description 4
- 239000012046 mixed solvent Substances 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 239000002585 base Substances 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- 235000014655 lactic acid Nutrition 0.000 description 3
- 239000004310 lactic acid Substances 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- FABVMBDCVAJXMB-UHFFFAOYSA-N 3,5-dichloro-2-hydroxybenzaldehyde Chemical compound OC1=C(Cl)C=C(Cl)C=C1C=O FABVMBDCVAJXMB-UHFFFAOYSA-N 0.000 description 2
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 2
- VKEQBMCRQDSRET-UHFFFAOYSA-N Methylone Chemical compound CNC(C)C(=O)C1=CC=C2OCOC2=C1 VKEQBMCRQDSRET-UHFFFAOYSA-N 0.000 description 2
- SMZOGRDCAXLAAR-UHFFFAOYSA-N aluminium isopropoxide Chemical compound [Al+3].CC(C)[O-].CC(C)[O-].CC(C)[O-] SMZOGRDCAXLAAR-UHFFFAOYSA-N 0.000 description 2
- 150000002148 esters Chemical class 0.000 description 2
- 150000002596 lactones Chemical class 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 230000009257 reactivity Effects 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- YJSATLBWFLERNZ-MDZDMXLPSA-N 2-[(e)-2-(2-aminophenyl)ethenyl]aniline Chemical compound NC1=CC=CC=C1\C=C\C1=CC=CC=C1N YJSATLBWFLERNZ-MDZDMXLPSA-N 0.000 description 1
- WSGYTJNNHPZFKR-UHFFFAOYSA-N 3-hydroxypropanenitrile Chemical compound OCCC#N WSGYTJNNHPZFKR-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 241000219000 Populus Species 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical class [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 229910021627 Tin(IV) chloride Inorganic materials 0.000 description 1
- 229940008309 acetone / ethanol Drugs 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 238000005576 amination reaction Methods 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 229920001585 atactic polymer Polymers 0.000 description 1
- 238000006065 biodegradation reaction Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 231100000252 nontoxic Toxicity 0.000 description 1
- 230000003000 nontoxic effect Effects 0.000 description 1
- 238000000655 nuclear magnetic resonance spectrum Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000005022 packaging material Substances 0.000 description 1
- 238000006068 polycondensation reaction Methods 0.000 description 1
- 239000002685 polymerization catalyst Substances 0.000 description 1
- 150000003606 tin compounds Chemical class 0.000 description 1
- KSBAEPSJVUENNK-UHFFFAOYSA-L tin(ii) 2-ethylhexanoate Chemical compound [Sn+2].CCCCC(CC)C([O-])=O.CCCCC(CC)C([O-])=O KSBAEPSJVUENNK-UHFFFAOYSA-L 0.000 description 1
- HPGGPRDJHPYFRM-UHFFFAOYSA-J tin(iv) chloride Chemical compound Cl[Sn](Cl)(Cl)Cl HPGGPRDJHPYFRM-UHFFFAOYSA-J 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
- C07F15/00—Compounds containing elements of Groups 8, 9, 10 or 18 of the Periodic Table
- C07F15/02—Iron compounds
- C07F15/025—Iron compounds without a metal-carbon linkage
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/02—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds
- C08G63/06—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds derived from hydroxycarboxylic acids
- C08G63/08—Lactones or lactides
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/78—Preparation processes
- C08G63/82—Preparation processes characterised by the catalyst used
- C08G63/823—Preparation processes characterised by the catalyst used for the preparation of polylactones or polylactides
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
Abstract
The present invention provides a kind of schiff bases iron compound, preparation method and its as the application of catalyst, schiff bases iron compound provided by the invention has structure shown in formula (I), wherein Y 1,2- ethyl group or 1,2- propyl；R is one of-H, halogen and alkyl.Schiff bases iron compound provided by the invention has NNOO quad-tree index ability, to form a metal active centres binding site, available four-coordination schiff bases iron catalyst.The schiff bases iron compound is used to be catalyzed the ring-opening polymerisation of lactide and caprolactone by the present invention, and catalytic activity is very high, while having comparable selectivity to rac-lactide, improves the regularity of polymerizate microstructure of molecular chain.Experiment shows the yield of method preparation polylactic acid provided by the invention up to 90%, and the yield of polycaprolactone is up to 96%.When lactide is rac-lactide, the three-dimensional regularity (Pm) of obtained polylactic acid is up to 0.60.
Description
Technical field
The present invention relates to technical field of polymer more particularly to a kind of schiff bases iron compounds, preparation method and its work
For the application of catalyst.
Background technique
Polylactic acid and polycaprolactone are chemical synthesis biodegradation material, in packaging material, biological medicine and pharmacy work
It has a wide range of applications in industry.The synthesis of polylactic acid generallys use two methods, i.e. lactide (cyclic dimer of lactic acid) is opened
Cyclopolymerization and direct polycondensation of lactic acid.The wherein method that high molecular polylactic acid generally uses lactide ring-opening polymerisation, and
There are lot of documents and patent to carry out relevant report to lactide ring-opening polymerisation, such as the United States Patent (USP) of Patent No. US5235031
With the United States Patent (USP) of Patent No. US5357034.Polycaprolactone similar with polylactic acid is also using internal ester monomer ring-opening polymerisation
It obtains.
Lactide is divided into three kinds of optical isomers: levorotatory lactide (LLA), and dextrorotation lactide (DLA) and meso third are handed over
Ester, structure difference are as follows:
The spatial configuration of lactide has conclusive work to the machinery of obtained polylactic acid, processing and degradation property
With.In order to obtain the polylactic acid of better performances, the prior art is frequently with levorotatory lactide or dextrorotation lactide nontoxic
Under the catalytic action of tin compound such as stannic chloride and stannous octoate, ring-opening polymerisation is carried out.Under the effect of tin series catalysts, optics
Ring-opening polymerisation obtains isotactic poly- dextrorotation lactide and poly- levorotatory lactide respectively by pure DLA, LLA, this two kinds polymerizations
Object is 180 DEG C of fusing point of crystalline polymer.But the product of rac-lactide ring-opening polymerisation under the same conditions is non-knot
Crystalline substance atactic polymer.Compared with amorphism polylactic acid, the use temperature range of crystalline polymer is wider, can be close to melting
Temperature.Since rac-lactide price is lower, it is therefore desirable to which developing a kind of pair of rac-lactide polymerization has stereoselectivity
Ring-opening polymerization catalyst, rac-lactide can be polymerize and obtain crystalline polylactic acid.
Currently, about the catalyst of lactide stereoselectivity ring-opening polymerisation, there are reports, such as Coates report
Schiff bases-Al catalysts (Salbinap) AlOMe be by a molecule 2,2'- diaminostilbene, 1'- connects dinaphthyl and two molecule bigcatkin willows
Aldehyde is condensed to yield schiff bases, then reacts to obtain with a molecule aluminium isopropoxide by a molecule schiff bases；The reports such as Zhong Zhiyuan
(cyclohexylsalen) AlOiPr catalyst is by a molecule 1,2- hexamethylene diamino and two molecules 3,5- di-t-butyl bigcatkin willow
Aldehyde is condensed to yield schiff bases, then reacts to obtain with a molecule aluminium isopropoxide by a molecule schiff bases.But the Schiff reported
For base catalyst in catalyzing ring-opening polymerization of lactide and catalysis caprolactone ring-opening polymerisation, the activity for being catalyzed reaction is lower, very
Hardly possible meets actual needs.
Summary of the invention
In view of this, the technical problem to be solved in the present invention is that providing a kind of schiff bases iron compound, preparation method
And its application as catalyst, schiff bases iron compound catalyzing ring-opening polymerization of lactide provided by the invention prepare polylactic acid
When, catalytic activity with higher；When catalysis caprolactone polymerization prepares polycaprolactone, it may have higher catalytic activity.
The present invention provides a kind of schiff bases iron compounds, have structure shown in formula (I):
Wherein, 1 Y, 2- ethyl group or 1,2- propyl；
R is one of-H, halogen and alkyl.
Preferably, it is one of 1~5 alkyl that the R, which is-H, halogen and carbon atom number,.
The present invention also provides a kind of preparation methods of schiff bases iron compound, comprising the following steps:
To there is the Schiff base ligand of structure shown in formula (II) to react in a solvent with ferric trichloride, obtain with formula (I)
The schiff bases iron compound of shown structure；
Wherein, 1 Y, 2- ethyl group or 1,2- propyl；
R is one of-H, halogen and alkyl.
Preferably, the Schiff base ligand of structure shown in the formula (II) is prepared according to the following steps:
To have the amine compound of structure shown in formula (III) and the bigcatkin willow aldehyde compound with structure shown in formula (IV)
Condensation reaction is carried out, the Schiff base ligand with structure shown in formula (II) is obtained；
Wherein, 1 Y, 2- ethyl group or 1,2- propyl；
R is one of-H, halogen and alkyl.
Preferably, the amine compound with structure shown in formula (III) and described with structure shown in formula (IV)
The molar ratio of bigcatkin willow aldehyde compound is 1:(2~4).
Preferably, the condensation reaction carries out under reflux conditions；
The time of the condensation reaction is 8h~16h.
Preferably, the molar ratio of the Schiff base ligand with structure shown in formula (II) and the ferric trichloride is 1:1.
Preferably, the temperature of the reaction is 25 DEG C~60 DEG C；The time of the reaction is 8h~12h.
The present invention also provides a kind of preparation methods of polylactic acid, comprising the following steps:
Lactide is mixed with catalyst, ring-opening polymerization is carried out in a solvent, obtains polylactic acid；
The catalyst is above-mentioned schiff bases iron compound or the schiff bases iron compound that above-mentioned preparation method is prepared.
Preferably, molar ratio 1:(50~1000 of the catalyst and the lactide).
Preferably, the temperature of the ring-opening polymerization is 25 DEG C~140 DEG C；
The time of the ring-opening polymerization is 1h~48h.
The present invention also provides a kind of preparation methods of polycaprolactone, comprising the following steps:
Caprolactone is mixed with catalyst, ring-opening polymerization is carried out in a solvent, obtains polycaprolactone；
The catalyst is above-mentioned schiff bases iron compound or the schiff bases iron compound that above-mentioned preparation method is prepared.
Preferably, molar ratio 1:(50~1000 of the catalyst and the caprolactone).
Preferably, the temperature of the ring-opening polymerization is 25 DEG C~100 DEG C；
The time of the ring-opening polymerization is 1h~48h.
The present invention provides a kind of schiff bases iron compound, preparation method and its as the application of catalyst, the present invention
The schiff bases iron compound of offer has structure shown in formula (I), wherein Y 1,2- ethyl group or 1,2- propyl；R be-H,
One of halogen and alkyl.Schiff bases iron compound provided by the invention has NNOO quad-tree index ability, to form one
A metal active centres binding site, available four-coordination schiff bases iron catalyst.The present invention is by the schiff bases iron chemical combination
Object is used to be catalyzed the ring-opening polymerisation of lactide and caprolactone, and schiff bases iron catalyst is to the ring-opening polymerisation of lactide and caprolactone
Ring-opening polymerisation has very high catalytic activity.The experimental results showed that the yield of method preparation polylactic acid provided by the invention can
Reach 90%, the yield of polycaprolactone can reach 96%.
Specific embodiment
Below in conjunction with the embodiment of the present invention, technical solution of the present invention is clearly and completely described, it is clear that institute
The embodiment of description is only a part of the embodiment of the present invention, instead of all the embodiments.Based on the embodiments of the present invention,
Every other embodiment obtained by those of ordinary skill in the art without making creative efforts, belongs to this hair
The range of bright protection.
The present invention provides a kind of schiff bases iron compounds, have structure shown in formula (I):
Wherein, 1 Y, 2- ethyl group or 1,2- propyl；
R is one of-H, halogen and alkyl.
Specifically, the R is preferably one of the alkyl that-H, halogen and carbon atom number are 1~5；More preferably-H, halogen
One of element, methyl and tert-butyl.
Schiff bases iron compound provided by the invention has the iron center of high activity, with schiff bases aluminium disclosed in the prior art
The catalyst at center is compared, and schiff bases iron compound provided by the invention is in catalysis lactide and caprolactone ring-opening polymerization
When, there is very high activity, the polymerization of monomer can be realized in room temperature, while having comparable selection to rac-lactide
Property, improve the regularity of polymerizate microstructure of molecular chain.
The present invention also provides a kind of preparation methods of schiff bases iron compound, comprising the following steps:
To there is the Schiff base ligand of structure shown in formula (II) to react in a solvent with ferric trichloride, obtain with formula (I)
The schiff bases iron compound of shown structure；
Wherein, 1 Y, 2- ethyl group or 1,2- propyl；
R is one of-H, halogen and alkyl.
The R is preferably one of the alkyl that-H, halogen and carbon atom number are 1~5；More preferably-H, halogen, methyl
One of with tert-butyl.
The present invention using with structure shown in formula (II) schiff bases and ferric trichloride as raw material, reaction obtain with formula (I)
The schiff bases iron compound of shown structure.In the present invention, the Schiff base ligand with structure shown in formula (II) is preferably pressed
It is prepared according to following steps:
To have the amine compound of structure shown in formula (III) and the bigcatkin willow aldehyde compound with structure shown in formula (IV)
Condensation reaction is carried out, the Schiff base ligand with structure shown in formula (II) is obtained；
Wherein, 1 Y, 2- ethyl group or 1,2- propyl；
R is one of-H, halogen and alkyl.
The R is preferably one of the alkyl that-H, halogen and carbon atom number are 1~5；More preferably-H, halogen, methyl
One of with tert-butyl.
Specifically, the present invention will preferably have the diamine compound of structure shown in formula (III) and have knot shown in formula (IV)
The bigcatkin willow aldehyde compound of structure mixes in ethanol, is heated to reflux, and carries out condensation reaction, obtains having structure shown in formula (II)
Schiff base ligand.
It is furthermore preferred that will there is the present invention diamine compound of structure shown in formula (III) to be dissolved in ethyl alcohol, two aminations are obtained
Polymer solution；To there is the bigcatkin willow aldehyde compound of formula (IV) described structure to be dissolved in ethyl alcohol, it is molten to obtain bigcatkin willow aldehyde compound
Liquid；The bigcatkin willow aldehydes compound solution is slowly added dropwise to the diamine compound solution, is heated to reflux, be condensed anti-
It answers, obtains the Schiff base ligand with structure shown in formula (II).In the present invention, two with structure shown in formula (III)
Amine compounds are preferably 1,2- ethylenediamine or 1,2- propane diamine；It is described to have formula (III) described in the diamine compound solution
The mass concentration of the diamine compound of structure is preferably 0.1g/mL~0.5g/mL, more preferably 0.15g/mL~0.3g/mL；Institute
Stating the bigcatkin willow aldehyde compound with formula (IV) described structure is preferably salicylide, 3,5- di-tert-butyl salicylaldehyde or two chloro-salicyloyls
Aldehyde；In the bigcatkin willow aldehydes compound solution, the mass concentration of the bigcatkin willow aldehyde compound with formula (IV) structure is preferred
For 0.1g/mL~0.5g/mL, more preferably 0.2g/mL~0.4g/mL.In the present invention, the temperature being heated to reflux is preferred
It is 20~140 DEG C；More preferably 50~100 DEG C；The time being heated to reflux is preferably 8h~16h；More preferably 11h~
13h；Most preferably 12h.In certain embodiments of the present invention, the temperature being heated to reflux is 80 DEG C, described to be heated to reflux
Time be 12h.
In the present invention, the amine compound with structure shown in formula (III) has knot shown in formula (IV) with described
The molar ratio of the bigcatkin willow aldehyde compound of structure is 1:(2~4), more preferably 1:2.
The temperature of above-mentioned condensation reaction is preferably 20~140 DEG C of temperature be heated to reflux；More preferably 50~100 DEG C；On
The time for stating condensation reaction is preferably the time 8h~16h being heated to reflux；More preferably 11h~13h；Most preferably 12h.
After above-mentioned condensation reaction, the solution that the condensation reaction obtains preferably is removed solvent by the present invention, then will remove solvent
Reaction product recrystallized, to obtain the Schiff base ligand with structure shown in formula (II).The present invention to it is described go it is molten
The method of agent and recrystallization does not have special limitation, goes the method for solvent and recrystallization i.e. using well known to those skilled in the art
It can.The solution that the present invention preferably obtains the condensation reaction carries out revolving and removes solvent therein, and the reaction of solvent will be gone to produce
Object is recrystallized using ethyl alcohol, obtains the Schiff base ligand with structure shown in formula (II).
After obtaining the Schiff base ligand with structure shown in formula (II), the present invention will have the Schiff of structure shown in formula (II)
Aar ligand reacts in a solvent with ferric trichloride, obtains the schiff bases iron compound with structure shown in formula (I).Specifically, this
Invention preferably under inert gas protection, will have the Schiff base ligand solution of structure shown in formula (II) and liquor ferri trichloridi mixed
Stirring is closed, the schiff bases iron compound with structure shown in formula (I) is obtained after reaction.In the present invention, described that there is formula (II)
The molar ratio of the Schiff base ligand of shown structure and the ferric trichloride is preferably 1:1.The present invention has formula (II) institute to described
The preparation method of the Schiff base ligand solution and liquor ferri trichloridi that show structure has no special limitation, using those skilled in the art
Solution preparation method known to member.The solvent of the Schiff base ligand solution with structure shown in formula (II) is preferably first
The mixed solvent of alcohol either methanol and acetonitrile；The molar concentration of the Schiff base ligand solution with structure shown in formula (II)
Preferably 0.5mol/L~2mol/L, more preferably 1mol/L~2mol/L.Solvent in the liquor ferri trichloridi is preferably
The mixed solvent of methanol either methanol and acetonitrile；The molar concentration of the liquor ferri trichloridi be preferably 0.5mol/L~
2mol/L, more preferably 1mol/L~2mol/L.The present invention has no special limitation to the solvent, it is preferred to use methanol or
It is the mixed solvent of methanol and acetonitrile.
In the present invention, the temperature of the Schiff base ligand and ferric chloride reaction with structure shown in formula (II) is preferred
It is 25 DEG C~60 DEG C；More preferably 25~40 DEG C.When the reaction dissolvent is methanol, the temperature of the reaction is preferably 25 DEG C.
Described to have the Schiff base ligand of structure and the time of ferric chloride reaction shown in formula (II) be preferably 8h~12h, more preferably
9h~10h.
After the reaction of the Schiff base ligand and ferric trichloride with formula (II) structure, the present invention is preferably by the reaction
Obtained solution removes solvent, then the reaction product of solvent will be gone to recrystallize, and obtains the Schiff with structure shown in formula (I)
Alkali iron compound.The present invention goes the method for solvent and recrystallization not have special limitation to described, using those skilled in the art
The well known method for removing solvent and recrystallization.It is therein molten that the solution that reaction obtains preferably is filtered removing by the present invention
Agent will go the reaction product of solvent using methylene chloride/methanol, methylene chloride/methanol acetonitrile, acetonitrile/ethyl alcohol, acetone/ethanol
Mixed solvent is recrystallized, and the schiff bases iron compound with structure shown in formula (I) is obtained.
The present invention also provides a kind of preparation methods of polylactic acid, comprising the following steps:
Lactide is mixed with catalyst, ring-opening polymerization is carried out in a solvent, obtains polylactic acid；
The catalyst is above-mentioned schiff bases iron compound or the schiff bases iron compound that above-mentioned preparation method is prepared.
The schiff bases iron compound is used to be catalyzed the ring-opening polymerisation of lactide by the present invention, and schiff bases iron catalyst is to third
The ring-opening polymerisation of lactide has very high activity, and the polymerization of monomer can be realized in room temperature, while having to rac-lactide
Comparable selectivity improves the regularity of polymerizate microstructure of molecular chain.
Specifically, the present invention preferably under the conditions of anhydrous and oxygen-free, lactide and catalyst is mixed in a solvent, under stirring
Ring-opening polymerization is carried out, polylactic acid is obtained.Catalyst schiff bases iron compound catalysis with higher provided by the invention is lived
Property, the selectivity of catalyzing ring-opening polymerization of lactide is preferable, can not only be catalyzed rac-lactide and obtain polylactic acid, can also urge
Change levorotatory lactide and dextrorotation lactide mixture obtains polylactic acid.The present invention does not have special limit to the source of the lactide
System, using the commercial goods of lactide, the present invention preferably recrystallizes the lactide of purchase, then carries out ring-opening polymerisation
Reaction.The present invention has no special limitation to the solvent, using it is well known to those skilled in the art can dissolve lactide and
The solvent of catalyst, the present invention are preferably propylene oxide or 7-oxa-bicyclo[4.1.0.The present invention does not have the mode of the stirring
Special limitation, by the way of stirring well known to those skilled in the art.
Schiff bases iron compound reactivity provided by the invention is higher, the dosage in catalyzing ring-opening polymerization of lactide compared with
Few, lower reaction temperature can be used in ring-opening polymerization.In the present invention, the molar ratio of the lactide and catalyst is preferred
For (50~1000): 1, more preferably (100~800): 1, most preferably (100~400): 1.The temperature of the ring-opening polymerization
Preferably 25 DEG C~140 DEG C of degree, more preferably 25 DEG C~60 DEG C, most preferably 25 DEG C；The time of the ring-opening polymerization is excellent
It is selected as 1h~48h, most preferably 12h.
After completing the ring-opening polymerization, the product of the ring-opening polymerization is preferably used chloroform by the present invention
Dissolution, adds excessive ethanol precipitation polymer, dry after filtering, obtains polylactic acid.The present invention is to the chloroform
Dosage does not have special limitation, can dissolve the product of the ring-opening polymerization.The present invention is to the filtering and does
Dry method does not have special limitation, using filtering well known to those skilled in the art and dry technical solution.At this
In invention, the drying is preferably dried in vacuo, and the time of the drying is preferably for 24 hours~48h, most preferably 36h.
After obtaining polylactic acid, the present invention is using homonuclear decoupling hydrogen nuclear magnetic resonance spectrum analysis selectivity.It polymerize poly- third obtained
The backbone sequence distribution of lactide indicates that segment is connected together by the lactide of identical configuration using " mmm ", [mmr],
[rmm], [mrm], [rmr] indicate that the lactide that there is not identical configuration in segment connects together.According to level-one Markovian
Five kinds of sequence relative intensities of statistics, poly- rac-lactide can be indicated by a parameter Pm: Pm refers to catalyst point
After the lactide of sub- one configuration of ring-opening polymerisation, continue probability of the polymerization one with identical configuration lactide, [mmm]=
Pm2+ (1-Pm) Pm/2, [rmm]=[mmr]=(1-Pm) Pm/2, [mrm]=[(1-Pm)2+ Pm (1-Pm)]/2, [rmr]=
[(1-Pm)2]/2.The result shows that schiff bases iron compound provided by the invention has stronger selection to lactide ring-opening polymerisation
Property, improve the regularity of polymerizate space structure.
The present invention also provides a kind of preparation methods of polycaprolactone, comprising the following steps:
Caprolactone is mixed with catalyst, ring-opening polymerization is carried out in a solvent, obtains polycaprolactone；
The catalyst is above-mentioned schiff bases iron compound or the schiff bases iron compound that above-mentioned preparation method is prepared.
The schiff bases iron compound is used to be catalyzed the ring-opening polymerisation of caprolactone by the present invention, and schiff bases iron catalyst is to oneself
The ring-opening polymerisation of lactone has very high activity, and the polymerization of monomer can be realized in room temperature.
Specifically, the present invention preferably under the conditions of anhydrous and oxygen-free, caprolactone and catalyst is mixed in a solvent, under stirring
Ring-opening polymerization polymer reaction is carried out, polycaprolactone is obtained.The present invention does not have special limitation to the source of the caprolactone, using oneself
The commercial goods of lactone, the present invention are preferably evaporated under reduced pressure the caprolactone of purchase, then carry out ring-opening polymerization.This
Invention has no special limitation to the solvent, using caprolactone and the catalyst well known to those skilled in the art of capable of dissolving
Solvent, the present invention are preferably propylene oxide or 7-oxa-bicyclo[4.1.0.The present invention does not have special limit to the mode of the stirring
System, using agitating mode well known to those skilled in the art.
Schiff bases iron compound reactivity provided by the invention is higher, the dosage when being catalyzed caprolactone ring-opening polymerisation compared with
Few, lower reaction temperature can be used in ring-opening polymerization.In the present invention, the molar ratio of the caprolactone and catalyst is preferred
For (50~1000): 1, more preferably (100~800): 1, most preferably (100~500): 1.The temperature of the ring-opening polymerization
Preferably 25 DEG C~100 DEG C of degree, more preferably 60 DEG C~100 DEG C, most preferably 100 DEG C；The time of the ring-opening polymerization
Preferably 1h~48h, most preferably 12h~for 24 hours.
After completing the ring-opening polymerization, the product of the ring-opening polymerization is preferably used chloroform by the present invention
Dissolution, adds excessive ethanol precipitation polymer, dry after filtering, obtains polycaprolactone.The present invention is to the chloroform
Dosage there is no special limitation, the product of the ring-opening polymerization can be dissolved.The present invention to it is described filtering and
Dry method does not have special limitation, using filtering well known to those skilled in the art and dry technical solution.In
In the present invention, the drying is preferably dried in vacuo, and the time of the drying is preferably for 24 hours~48h, most preferably 36h.
The present invention has no special limitation to the source of above-mentioned used raw material, can be general commercially available.
The present invention provides a kind of schiff bases iron compound, preparation method and its as the application of catalyst, the present invention
The schiff bases iron compound of offer has structure shown in formula (I), wherein Y 1,2- ethyl group or 1,2- propyl；R is-H, halogen
One of element and alkyl.Schiff bases iron compound provided by the invention has NNOO quad-tree index ability, to form one
Metal active centres binding site, available four-coordination schiff bases iron catalyst.The present invention is by the schiff bases iron compound
For being catalyzed the ring-opening polymerisation of lactide and caprolactone, schiff bases iron catalyst is to the ring-opening polymerisation of lactide and opening for caprolactone
Cyclopolymerization has very high catalytic activity, and the polymerization of monomer can be realized in room temperature, while having to rac-lactide suitable
Selectivity, improve the regularity of polymerizate microstructure of molecular chain.The experimental results showed that method preparation provided by the invention is poly-
The yield of lactic acid can reach 90%, and the yield of polycaprolactone can reach 96%.When lactide is rac-lactide, obtain
The three-dimensional regularity (Pm) of polylactic acid is up to 0.60.
In order to further illustrate the present invention, below with reference to embodiment to schiff bases iron compound provided by the invention, its system
Preparation Method and its application as catalyst are described in detail, but they cannot be interpreted as to the scope of the present invention
It limits.
Embodiment 1
By 0.74g1,2- ethylenediamine is dissolved in 20mL ethyl alcohol, obtains 1,2- ethylenediamine solution；2.5g salicylide is dissolved in
In 30mL ethyl alcohol, salicylide solution is obtained, salicylide solution is slowly added dropwise to the mixed solution obtained to 1,2- ethylenediamine solution
In 80 DEG C of reflux 12h, reaction mixture is obtained.The solvent being filtered to remove in reaction mixture uses obtained reaction product
Ethyl alcohol recrystallization obtains Schiff base ligand.Obtained schiff base compound is carried out elemental analysis by the present invention, obtains wherein each original
The content of son is as a result as follows: Elem.Anal. (%): Calcd.C 71.62, H 6.01, N 10.44；Found C 71.51,
H6.03, N 10.33.This explanation, the Schiff base ligand that the present embodiment obtains have structure shown in formula (II), and wherein Y is 1,2- second
Alkyl；R is H.
Embodiment 2
By 0.6g1,2- ethylenediamine is dissolved in 20mL ethyl alcohol, obtains 1,2- ethylenediamine solution；By 4.7g3,5- di-t-butyl
Salicylide is dissolved in 30mL ethyl alcohol, obtains 3,5- di-tert-butyl salicylaldehyde solution, and 3,5- di-tert-butyl salicylaldehyde solution is slow
It is added dropwise to 1,2- ethylenediamine solution, obtained mixed solution obtains reaction mixture in 80 DEG C of reflux 12h.It is filtered to remove reaction
Obtained reaction product is obtained Schiff base ligand using ethyl alcohol recrystallization by the solvent of mixture.The Schiff that the present invention will obtain
Alkali cpd carries out elemental analysis, obtains the content of wherein each atom, as a result as follows: Elem.Anal. (%): Calcd.C
78.00, H9.82, N 5.69；Found C 77.58, H 9.88, N 5.77.This explanation, the schiff bases that the present embodiment obtains are matched
Body has structure shown in formula (II), and wherein Y is 1,2- ethyl group；R is tert-butyl.
Embodiment 3
By 0.74g1,2- propane diamine is dissolved in 20mL ethyl alcohol, obtains 1,2- propane diamine solution；By 4.7g3,5- di-t-butyl
Salicylide is dissolved in 30mL ethyl alcohol, obtains 3,5- di-tert-butyl salicylaldehyde solution, and 3,5- di-tert-butyl salicylaldehyde solution is slow
It is added dropwise to 1,2- propane diamine solution, obtained mixed solution obtains reaction mixture in 80 DEG C of reflux 12h.It is filtered to remove reaction
Obtained reaction product is used ethyl alcohol by the solvent of mixture) it is recrystallized to give Schiff base ligand.The Schiff that the present invention will obtain
Alkali cpd carries out elemental analysis, obtains the content of wherein each atom, as a result as follows: Elem.Anal. (%): Calcd.C
78.21, H9.95, N 5.53；Found C 78.26, H 9.98, N 5.47.This explanation, the schiff bases that the present embodiment obtains are matched
Body has structure shown in formula (II), and wherein Y is 1,2- alkyl；R is tert-butyl.
Embodiment 4
By 0.6g 1,2- ethylenediamine is dissolved in 20mL ethyl alcohol, obtains 1,2- ethylenediamine solution；By 3.8g3,5- di-t-butyl
Salicylide is dissolved in 30mL ethyl alcohol, obtains 3,5- di-tert-butyl salicylaldehyde solution, and 3,5- di-tert-butyl salicylaldehyde solution is slow
It is added dropwise to 1,2- ethylenediamine solution, obtained mixed solution obtains reaction mixture in 80 DEG C of reflux 12h.It is filtered to remove reaction
Obtained reaction product is obtained Schiff base ligand using ethyl alcohol recrystallization by the solvent of mixture.The Schiff that the present invention will obtain
Alkali cpd carries out elemental analysis, obtains the content of wherein each atom, as a result as follows: Elem.Anal. (%): Calcd.C
47.32, H2.98, N 6.90；Found C 47.22, H 2.91, N 6.87.This explanation, the schiff bases that the present embodiment obtains are matched
Body has structure shown in formula (II), and wherein Y is 1,2- ethyl group；R is chlorine.
Embodiment 5
By 0.74g 1,2- propane diamine is dissolved in 20mL ethyl alcohol, obtains 1,2- propane diamine solution；By bis- chlorine water of 3.8g3,5-
Poplar aldehyde is dissolved in 30mL ethyl alcohol, obtains 3,5- dichloro-salicylaldehyde's solution, and 3,5- dichloro-salicylaldehyde is slowly added dropwise to 1,2- the third two
Amine aqueous solution, obtained mixed solution obtain reaction mixture in 80 DEG C of reflux 12h.It is filtered to remove the solvent of reaction mixture, it will
Obtained reaction product obtains Schiff base ligand using ethyl alcohol recrystallization.Obtained schiff base compound is carried out element by the present invention
Analysis, obtains the content of wherein each atom, as a result as follows: Elem.Anal. (%): Calcd.C 48.60, H 3.36, N
6.67；Found C 48.68, H 3.31, N 6.76.This explanation, the Schiff base ligand that the present embodiment obtains have formula (II) institute
Show structure, wherein Y is 1,2- propyl；R is chlorine.
Embodiment 6
Under conditions of inert gas shielding, the Schiff base ligand that 1g embodiment 1 obtains is mixed with 0.4g ferric trichloride
Afterwards, 20mL methanol is added to be mixed, by obtained mixed solution in 25 DEG C of reaction 10h, completes reaction system mistake after reacting
Filter out solvent, methylene chloride/methanol recrystallization；Obtain schiff bases iron compound.
Obtained schiff bases iron compound is carried out elemental analysis by the present invention, obtains the content of wherein each atom, as a result such as
Under: Elem.Anal. (%): C 53.75, H3.95, N 7.83；Found C 53.71, H3.91, N 7.88.This explanation, this reality
Applying the schiff bases iron compound that example obtains has structure shown in formula (I), and wherein Y is 1,2- ethyl group；R is H.
Embodiment 7
Under conditions of inert gas shielding, the Schiff base ligand that 1g embodiment 2 obtains is mixed with 0.4g ferric trichloride
Afterwards, 20mL methanol is added to be mixed, by obtained mixed solution in 25 DEG C of reaction 10h, completes reaction system mistake after reacting
Filter out solvent, methylene chloride/methanol recrystallization；Obtain schiff bases iron compound.
Obtained schiff bases iron compound is carried out elemental analysis by the present invention, obtains the content of wherein each atom, as a result such as
Under: Elem.Anal. (%): Calcd.C 66.04, H 7.97, N 4.81；Found C 65.08,H 7.515,N 4.58.This
Illustrate, the schiff bases iron compound that the present embodiment obtains has structure shown in formula (I), and wherein Y is 1,2- ethyl group；R is tertiary fourth
Base.
Embodiment 8
Under conditions of inert gas shielding, the Schiff base ligand that 1g embodiment 3 obtains is mixed with 0.3g ferric trichloride
Afterwards, 15mL methanol, the mixing of 25mL acetonitrile is added, by obtained mixed solution in 60 DEG C of reaction 9h, completing will be anti-after reacting
System is answered to be filtered to remove solvent, methylene chloride/methanol recrystallized from acetonitrile；Obtain schiff bases iron compound.
Obtained schiff bases iron compound is carried out elemental analysis by the present invention, obtains the content of wherein each atom, as a result such as
Under: Elem.Anal. (%): Calcd.C 66.50, H 8.12；N 4.70；Found C 65.85,H 7.536,N 4.55.This
Illustrate, the schiff bases iron compound that the present embodiment obtains has structure shown in formula (I), and wherein Y is 1,2- propyl；R is tertiary fourth
Base.
Embodiment 9
Under conditions of inert gas shielding, the Schiff base ligand that 1g embodiment 4 obtains is mixed with 0.4g ferric trichloride
Afterwards, 15mL methanol, the mixing of 25mL acetonitrile is added, by obtained mixed solution in 25 DEG C of reaction 9h, completing will be anti-after reacting
System is answered to be filtered to remove solvent, methylene chloride/methanol recrystallized from acetonitrile；Obtain schiff bases iron compound.
Obtained schiff bases iron compound is carried out elemental analysis by the present invention, obtains the content of wherein each atom, as a result such as
Under: Elem.Anal. (%): Calcd.C 38.79, H 2.03；N 5.66；Found C 37.91,H 2.399,N 5.57.This
Illustrate, the schiff bases iron compound that the present embodiment obtains has structure shown in formula (I), and wherein Y is 1,2- ethyl group；R is chlorine.
Embodiment 10
Under conditions of inert gas shielding, the Schiff base ligand that 1g embodiment 5 obtains is mixed with 0.4g ferric trichloride
Afterwards, 15mL methanol, the mixing of 25mL acetonitrile is added, by obtained mixed solution in 25 DEG C of reaction 9h, completing will be anti-after reacting
System is answered to be filtered to remove solvent, methylene chloride/methanol recrystallized from acetonitrile；Obtain schiff bases iron compound.
Obtained schiff bases iron compound is carried out elemental analysis by the present invention, obtains the content of wherein each atom, as a result such as
Under: Elem.Anal. (%): Calcd.C 40.08, H 2.37；N 5.50；Found C 39.31,H 2.458,N 5.36.This
Illustrate, the schiff bases iron compound that the present embodiment obtains has structure shown in formula (I), and wherein Y is 1,2- propyl；R is chlorine.
Embodiment 11
Under conditions of anhydrous and oxygen-free, levorotatory lactide that 20.0mmol was recrystallized, 0.2mmol embodiment 6 are obtained
Schiff bases iron compound mixed with 20mL propylene oxide, obtained mixed solution is stirred to react 12h at 100 DEG C, to obtaining
Reaction solution in 10mL chloroform be added dissolve polymer, then excessive ethanol precipitation polymer is added thereto, filters,
It is dried in vacuo 48h, obtains polylactic acid.
The quality that the present invention weighs to obtain polylactic acid is 2.6g；The yield of polylactic acid is 90%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 1.4 ten thousand.
Embodiment 12
Polylactic acid is prepared using the technical solution of embodiment 11 in the present invention, unlike, the present embodiment uses dextrorotation
The levorotatory lactide that lactide replaces embodiment 11 to use.
The quality that the present invention weighs to obtain polylactic acid is 2.7g；The yield of polylactic acid is 94%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 1.95 ten thousand.
Embodiment 13
Polylactic acid is prepared using the technical solution of embodiment 11 in the present invention, unlike, the present embodiment uses to disappear outside
Revolve the levorotatory lactide that lactide replaces embodiment 11 to use.
The quality that the present invention weighs to obtain polylactic acid is 2.6g；The yield of polylactic acid is 90%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 1.88 ten thousand；
The present invention analyzes the polylactic acid that the present embodiment obtains using homonuclear decoupling nuclear magnetic resonance spectroscopy, obtains poly- cream
The Pm of acid is 0.44.
Embodiment 14
Under conditions of anhydrous and oxygen-free, caprolactone that 20.0mmol was evaporated under reduced pressure, 0.2mmol embodiment 6 are obtained
Schiff bases iron compound is mixed with 20mL propylene oxide, obtained mixed solution is stirred to react 32h at 100 DEG C, to what is obtained
10mL chloroform is added in reaction solution and dissolves polymer, then excessive ethanol precipitation polymer is added thereto, filters, very
The dry 48h of sky, obtains polycaprolactone.
The quality that the present invention weighs to obtain polycaprolactone is 2.2g；The yield of polycaprolactone is 96%.
The present invention carries out the polycaprolactone that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining caprolactone is 1.8 ten thousand.
Embodiment 15
Under conditions of anhydrous and oxygen-free, levorotatory lactide that 20.0mmol was recrystallized, 0.1mmol embodiment 7 are obtained
Schiff bases iron compound mixed with 20mL propylene oxide, obtained mixed solution is stirred to react 4h at 100 DEG C, to what is obtained
10mL chloroform is added in reaction solution and dissolves polymer, then excessive ethanol precipitation polymer is added thereto, filters, very
The dry 48h of sky, obtains polylactic acid.
The quality that the present invention weighs to obtain polylactic acid is 2.6g；The yield of polylactic acid is 90%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 3.2 ten thousand.
Embodiment 16
Polylactic acid is prepared using the technical solution of embodiment 15 in the present invention, unlike, the present embodiment uses dextrorotation
The levorotatory lactide that lactide replaces embodiment 15 to use.
The quality that the present invention weighs to obtain polylactic acid is 2.7g；The yield of polylactic acid is 94%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 3.1 ten thousand.
Embodiment 17
Polylactic acid is prepared using the technical solution of embodiment 15 in the present invention, unlike, the present embodiment uses to disappear outside
Revolve the levorotatory lactide that lactide replaces embodiment 15 to use.
The quality that the present invention weighs to obtain polylactic acid is 2.7g；The yield of polylactic acid is 94%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 3.01 ten thousand；
The present invention analyzes the polylactic acid that the present embodiment obtains using homonuclear decoupling nuclear magnetic resonance spectroscopy, obtains poly- cream
The Pm of acid is 0.58.
Embodiment 18
Under conditions of anhydrous and oxygen-free, caprolactone that 20.0mmol was evaporated under reduced pressure, 0.1mmol embodiment 7 are obtained
Schiff bases iron compound is mixed with 20mL propylene oxide, obtained mixed solution is stirred to react 3.9h at 100 DEG C, to what is obtained
10mL chloroform is added in reaction solution and dissolves polymer, then excessive ethanol precipitation polymer is added thereto, filters, very
The dry 48h of sky, obtains polycaprolactone.
The quality that the present invention weighs to obtain polycaprolactone is 2.2g；The yield of polycaprolactone is 96%.
The present invention carries out the polycaprolactone that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polycaprolactone is 2.5 ten thousand.
Embodiment 19
Under conditions of anhydrous and oxygen-free, levorotatory lactide that 20.0mmol was recrystallized, 0.1mmol embodiment 8 are obtained
Schiff bases iron compound mixed with 20mL propylene oxide, obtained mixed solution is stirred to react 5h at 100 DEG C, to what is obtained
10mL chloroform is added in reaction solution and dissolves polymer, then excessive ethanol precipitation polymer is added thereto, filters, very
The dry 48h of sky, obtains polylactic acid.
The quality that the present invention weighs to obtain polylactic acid is 2.8g；The yield of polylactic acid is 97%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 3.7 ten thousand.
Embodiment 20
Polylactic acid is prepared using the technical solution of embodiment 19 in the present invention, unlike, the present embodiment uses dextrorotation
The levorotatory lactide that lactide replaces embodiment 19 to use.
The quality that the present invention weighs to obtain polylactic acid is 2.7g；The yield of polylactic acid is 94%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 3.75 ten thousand.
Embodiment 21
Polylactic acid is prepared using the technical solution of embodiment 19 in the present invention, unlike, the present embodiment uses to disappear outside
Revolve the levorotatory lactide that lactide replaces embodiment 19 to use.
The quality that the present invention weighs to obtain polylactic acid is 2.6g；The yield of polylactic acid is 90%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 3.60 ten thousand；
The present invention analyzes the polylactic acid that the present embodiment obtains using homonuclear decoupling nuclear magnetic resonance spectroscopy, obtains poly- cream
The Pm of acid is 0.60.
Embodiment 22
Under conditions of anhydrous and oxygen-free, caprolactone that 20.0mmol was evaporated under reduced pressure, 0.04mmol embodiment 8 are obtained
Schiff bases iron compound is mixed with 20mL propylene oxide, and obtained mixed solution is stirred to react 4h at 100 DEG C, anti-to what is obtained
It answers and 10mL chloroform dissolution polymer is added in solution, then excessive ethanol precipitation polymer is added thereto, filter, vacuum
Dry 48h, obtains polycaprolactone.
The quality that the present invention weighs to obtain polycaprolactone is 2.2g；The yield of polycaprolactone is 96%.
The present invention carries out the polycaprolactone that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polycaprolactone is 5.6 ten thousand.
Embodiment 23
Under conditions of anhydrous and oxygen-free, levorotatory lactide that 20.0mmol was recrystallized, 0.1mmol embodiment 9 are obtained
Schiff bases iron compound mixed with 20mL propylene oxide, obtained mixed solution is stirred to react 4h at 100 DEG C, to what is obtained
10mL chloroform is added in reaction solution and dissolves polymer, then excessive ethanol precipitation polymer is added thereto, filters, very
The dry 48h of sky, obtains polylactic acid.
The quality that the present invention weighs to obtain polylactic acid is 2.6g；The yield of polylactic acid is 90%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 3.7 ten thousand.
Embodiment 24
Polylactic acid is prepared using the technical solution of embodiment 23 in the present invention, unlike, the present embodiment uses dextrorotation
The levorotatory lactide that lactide replaces embodiment 23 to use.
The quality that the present invention weighs to obtain polylactic acid is 2.7g；The yield of polylactic acid is 94%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 3.75 ten thousand.
Embodiment 25
Polylactic acid is prepared using the technical solution of embodiment 23 in the present invention, unlike, the present embodiment uses to disappear outside
Revolve the levorotatory lactide that lactide replaces embodiment 23 to use.
The quality that the present invention weighs to obtain polylactic acid is 2.6g；The yield of polylactic acid is 90%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 3.60 ten thousand；
The present invention analyzes the polylactic acid that the present embodiment obtains using homonuclear decoupling nuclear magnetic resonance spectroscopy, obtains poly- cream
The Pm of acid is 0.37.
Embodiment 26
Under conditions of anhydrous and oxygen-free, caprolactone that 20.0mmol was evaporated under reduced pressure, 0.04mmol embodiment 9 are obtained
Schiff bases iron compound is mixed with 20mL propylene oxide, and obtained mixed solution is stirred to react 2h at 40 DEG C, anti-to what is obtained
It answers and 10mL chloroform dissolution polymer is added in solution, then excessive ethanol precipitation polymer is added thereto, filter, vacuum
Dry 48h, obtains polycaprolactone.
The quality that the present invention weighs to obtain polycaprolactone is 2.2g；The yield of polycaprolactone is 96%.
The present invention carries out the polycaprolactone that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polycaprolactone is 5.6 ten thousand.
Embodiment 27
Under conditions of anhydrous and oxygen-free, levorotatory lactide that 20.0mmol was recrystallized, 0.1mmol embodiment 10 are obtained
Schiff bases iron compound mixed with 20mL propylene oxide, obtained mixed solution is stirred to react 4h at 100 DEG C, to what is obtained
10mL chloroform is added in reaction solution and dissolves polymer, then excessive ethanol precipitation polymer is added thereto, filters, very
The dry 48h of sky, obtains polylactic acid.
The quality that the present invention weighs to obtain polylactic acid is 2.7g；The yield of polylactic acid is 94%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 3.7 ten thousand.
Embodiment 28
Polylactic acid is prepared using the technical solution of embodiment 27 in the present invention, unlike, the present embodiment uses dextrorotation
The levorotatory lactide that lactide replaces embodiment 27 to use.
The quality that the present invention weighs to obtain polylactic acid is 2.8g；The yield of polylactic acid is 97%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 3.75 ten thousand.
Embodiment 29
Polylactic acid is prepared using the technical solution of embodiment 27 in the present invention, unlike, the present embodiment uses to disappear outside
Revolve the levorotatory lactide that lactide replaces embodiment 27 to use.
The quality that the present invention weighs to obtain polylactic acid is 2.6g；The yield of polylactic acid is 90%.
The present invention divides the polylactic acid that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polylactic acid is 3.60 ten thousand；
The present invention analyzes the polylactic acid that the present embodiment obtains using homonuclear decoupling nuclear magnetic resonance spectroscopy, obtains poly- cream
The Pm of acid is 0.47.
Embodiment 30
Under conditions of anhydrous and oxygen-free, caprolactone that 20.0mmol was evaporated under reduced pressure, 0.04mmol embodiment 10 are obtained
Schiff bases iron compound mixed with 20mL propylene oxide, obtained mixed solution is stirred to react 2h at 60 DEG C, to what is obtained
10mL chloroform is added in reaction solution and dissolves polymer, then excessive ethanol precipitation polymer is added thereto, filters, very
The dry 48h of sky, obtains polycaprolactone.
The quality that the present invention weighs to obtain polycaprolactone is 2.2g；The yield of polycaprolactone is 96%.
The present invention carries out the polycaprolactone that the present embodiment obtains using polystyrene as reference substance, using gel permeation chromatography
Analysis, the number-average molecular weight for obtaining polycaprolactone is 5.6 ten thousand.
As seen from the above embodiment, the present invention provides a kind of schiff bases iron compound, preparation method and its as urging
The application of agent, schiff bases iron compound provided by the invention have structure shown in formula (I), wherein Y 1,2- ethyl group or 1,
2- propyl；R is one of-H, halogen and alkyl.Schiff bases iron compound provided by the invention has NNOO quad-tree index
Ability, to form a metal active centres binding site, available four-coordination schiff bases iron catalyst.The present invention is by institute
Schiff bases iron compound is stated for being catalyzed the ring-opening polymerisation of lactide and caprolactone, open loop of the schiff bases iron catalyst to lactide
Polymerization and the ring-opening polymerisation of caprolactone have very high catalytic activity, while having comparable selection to rac-lactide
Property, improve the regularity of polymerizate microstructure of molecular chain.The experimental results showed that method preparation polylactic acid provided by the invention
Yield can reach 90%, and the yield of polycaprolactone can reach 96%.When lactide is rac-lactide, obtained polylactic acid
Three-dimensional regularity (Pm) up to 0.60.
The above is only a preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
For member, various improvements and modifications may be made without departing from the principle of the present invention, these improvements and modifications are also answered
It is considered as protection scope of the present invention.
Claims (18)
1. a kind of preparation method of polylactic acid, comprising the following steps:
Lactide is mixed with catalyst, ring-opening polymerization is carried out in a solvent, obtains polylactic acid；
The catalyst is the schiff bases iron compound with structure shown in formula (I):
Wherein, 1 Y, 2- propyl；
R is tert-butyl；
The solvent is propylene oxide.
2. preparation method according to claim 1, which is characterized in that the schiff bases iron with structure shown in formula (I)
The preparation method of compound the following steps are included:
To there is the Schiff base ligand of structure shown in formula (II) to react in a solvent with ferric trichloride, obtain with shown in formula (I)
The schiff bases iron compound of structure；
Wherein, 1 Y, 2- propyl；
R is tert-butyl.
3. preparation method according to claim 2, which is characterized in that the Schiff base ligand of structure shown in the formula (II) is pressed
It is prepared according to following steps:
There to be the amine compound of structure shown in formula (III) to carry out with the bigcatkin willow aldehyde compound with structure shown in formula (IV)
Condensation reaction obtains the Schiff base ligand with structure shown in formula (II)；
Wherein, 1 Y, 2- propyl；
R is tert-butyl.
4. preparation method according to claim 3, which is characterized in that described with the aminated of structure shown in formula (III)
The molar ratio for closing object and the bigcatkin willow aldehyde compound with structure shown in formula (IV) is 1:(2~4).
5. preparation method according to claim 3, which is characterized in that the condensation reaction carries out under reflux conditions；
The time of the condensation reaction is 8h~16h.
6. preparation method according to claim 2, which is characterized in that the schiff bases with structure shown in formula (II) are matched
The molar ratio of body and the ferric trichloride is 1:1.
7. preparation method according to claim 2, which is characterized in that the temperature of the reaction is 25 DEG C~60 DEG C；It is described
The time of reaction is 8h~12h.
8. preparation method according to claim 1, which is characterized in that the molar ratio 1 of the catalyst and the lactide:
(50~1000).
9. preparation method according to claim 1, which is characterized in that the temperature of the ring-opening polymerization be 25 DEG C~
140℃；
The time of the ring-opening polymerization is 1h~48h.
10. a kind of preparation method of polycaprolactone, comprising the following steps:
Caprolactone is mixed with catalyst, ring-opening polymerization is carried out in a solvent, obtains polycaprolactone；
The catalyst is the schiff bases iron compound with structure shown in formula (I):
Wherein, 1 Y, 2- propyl；
R is tert-butyl；
The solvent is propylene oxide.
11. preparation method according to claim 10, which is characterized in that the schiff bases with structure shown in formula (I)
The preparation method of iron compound the following steps are included:
To there is the Schiff base ligand of structure shown in formula (II) to react in a solvent with ferric trichloride, obtain with shown in formula (I)
The schiff bases iron compound of structure；
Wherein, 1 Y, 2- propyl；
R is tert-butyl.
12. preparation method according to claim 11, which is characterized in that the Schiff base ligand of structure shown in the formula (II)
It is prepared according to the following steps:
There to be the amine compound of structure shown in formula (III) to carry out with the bigcatkin willow aldehyde compound with structure shown in formula (IV)
Condensation reaction obtains the Schiff base ligand with structure shown in formula (II)；
Wherein, 1 Y, 2- propyl；
R is tert-butyl.
13. preparation method according to claim 12, which is characterized in that the amido with structure shown in formula (III)
The molar ratio of compound and the bigcatkin willow aldehyde compound with structure shown in formula (IV) is 1:(2~4).
14. preparation method according to claim 12, which is characterized in that the condensation reaction carries out under reflux conditions；
The time of the condensation reaction is 8h~16h.
15. preparation method according to claim 11, which is characterized in that the schiff bases with structure shown in formula (II)
The molar ratio of ligand and the ferric trichloride is 1:1.
16. preparation method according to claim 11, which is characterized in that the temperature of the reaction is 25 DEG C~60 DEG C；Institute
The time for stating reaction is 8h~12h.
17. preparation method according to claim 10, which is characterized in that the molar ratio of the catalyst and the caprolactone
1:(50~1000).
18. preparation method according to claim 10, which is characterized in that the temperature of the ring-opening polymerization be 25 DEG C~
100℃；
The time of the ring-opening polymerization is 1h~48h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710427791.XA CN107033193B (en) | 2017-06-08 | 2017-06-08 | A kind of schiff bases iron compound, preparation method and its application as catalyst |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710427791.XA CN107033193B (en) | 2017-06-08 | 2017-06-08 | A kind of schiff bases iron compound, preparation method and its application as catalyst |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107033193A CN107033193A (en) | 2017-08-11 |
| CN107033193B true CN107033193B (en) | 2019-11-15 |
Family
ID=59540849
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710427791.XA Active CN107033193B (en) | 2017-06-08 | 2017-06-08 | A kind of schiff bases iron compound, preparation method and its application as catalyst |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107033193B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109897072B (en) * | 2017-12-11 | 2021-05-18 | 北京服装学院 | Iron-containing complex, preparation thereof, catalyst composition containing iron-containing complex and polymerization of caprolactone by using catalyst composition |
| CN108912010B (en) * | 2018-08-01 | 2021-04-06 | 中国科学院长春应用化学研究所 | Schiff base manganese compound, and preparation method and application thereof |
| CN108610475A (en) * | 2018-08-13 | 2018-10-02 | 中国科学院长春应用化学研究所 | A kind of preparation method of polylactic acid-polycaprolactone co-polymer |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003064174A (en) * | 2001-08-24 | 2003-03-05 | Nagoya Industrial Science Research Inst | Lactone ring-opening polymerization catalyst, method for producing polyester, and method for producing block copolymer |
| CN103097432A (en) * | 2010-06-17 | 2013-05-08 | 日立造船株式会社 | Method for producing polylactic acid |
-
2017
- 2017-06-08 CN CN201710427791.XA patent/CN107033193B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003064174A (en) * | 2001-08-24 | 2003-03-05 | Nagoya Industrial Science Research Inst | Lactone ring-opening polymerization catalyst, method for producing polyester, and method for producing block copolymer |
| CN103097432A (en) * | 2010-06-17 | 2013-05-08 | 日立造船株式会社 | Method for producing polylactic acid |
Non-Patent Citations (3)
| Title |
|---|
| CAS RN：1817619-96-7等;Chemical Abstract Service;《CA 网络版 STN Registry数据库》;20151030;CAS RN：1817619-96-7等 * |
| Ring opening polymerization of dilactide using salen complex as catalyst;B.B. Idage等;《Materials Science and Engineering B》;20091029;193-198页 * |
| Spectral, Computational, Electrochemical and Antibacterial Studies of Iron(III)–Salen Complexes;P. Karuppasamy等;《Arab. J. Sci. Eng.》;20150221;2945-2958页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107033193A (en) | 2017-08-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Chen et al. | Preparation and characterization of aluminum alkoxides coordinated on salen-type ligands: highly stereoselective ring-opening polymerization of rac-lactide | |
| Tang et al. | Synthesis and structural characterization of magnesium ketiminate complexes: efficient initiators for the ring-opening polymerization of L-lactide | |
| Liu et al. | Bis (imino) aryl NCN pincer aluminum and zinc complexes: synthesis, characterization, and catalysis on l-Lactide polymerization | |
| Hung et al. | Preparation, characterization, and catalytic studies of magnesium complexes supported by NNO-tridentate Schiff-base ligands | |
| Labourdette et al. | Unusually stable chiral ethyl zinc complexes: reactivity and polymerization of lactide | |
| Samantaray et al. | Silver N-heterocyclic carbene complexes as initiators for bulk ring-opening polymerization (ROP) of l-lactides | |
| Gao et al. | Stereoselective ring-opening polymerization of rac-lactides catalyzed by aluminum hemi-salen complexes | |
| Allen et al. | Structure and reactivity of mono-and dinuclear diiminate zinc alkyl complexes | |
| Ou et al. | Synthesis of sodium complexes supported with NNO-tridentate Schiff base ligands and their applications in the ring-opening polymerization of L-lactide | |
| Sun et al. | Bimetallic lanthanide amido complexes as highly active initiators for the ring-opening polymerization of lactides | |
| Tsai et al. | Tridentate anilido‐aldimine magnesium and zinc complexes as efficient catalysts for ring‐opening polymerization of ε‐caprolactone and l‐lactide | |
| Chuang et al. | Efficient zinc initiators supported by NNO‐tridentate ketiminate ligands for cyclic esters polymerization | |
| CN107033193B (en) | A kind of schiff bases iron compound, preparation method and its application as catalyst | |
| Kronast et al. | Electron-deficient β-diiminato-zinc-ethyl complexes: Synthesis, structure, and reactivity in ring-opening polymerization of lactones | |
| Darensbourg et al. | Manganese (III) schiff base complexes: Chemistry relevant to the copolymerization of epoxides and carbon dioxide | |
| Koller et al. | Highly efficient aluminum-catalyzed ring-opening polymerization of cyclic carbonates, lactones, and lactides, including a unique crystallographic snapshot of an intermediate | |
| Pappuru et al. | Group 4 complexes of salicylbenzoxazole ligands as effective catalysts for the ring-opening polymerization of lactides, epoxides and copolymerization of ε-caprolactone with L-lactide | |
| CN107417739B (en) | A kind of schiff bases iron compound, preparation method and its application as catalyst | |
| Gallaway et al. | Ring-opening polymerization of rac-lactide and ε-caprolactone using zinc and calcium salicylaldiminato complexes | |
| Eckert et al. | Simple is best: Diamine zinc complexes as unexpected catalysts in lactide polymerisation | |
| Nayab et al. | Synthesis and structural characterization of a dichloro zinc complex of N, N′-bis-(2, 6-dichloro-benzyl)-(R, R)-1, 2-diaminocyclohexane: Application to ring opening polymerization of rac-lactide | |
| Malthus et al. | First row transition metal complexes of di-o-substituted-diarylamine-based ligands (including carbazoles, acridines and dibenzoazepines) | |
| Kwon et al. | Synthesis, characterisation and X-ray structure of Cu (II) and Zn (II) complexes bearing N, N-dimethylethylenamine-camphorylimine ligands: Application in the polymerisation of rac-lactide | |
| Daneshmand et al. | Catalytic-site-mediated chain-end control in the polymerization of rac-lactide with copper iminopyrrolide complexes | |
| Li et al. | Phenoxyimine ligands bearing nitrogen-containing second coordination spheres for zinc catalyzed stereoselective ring-opening polymerization of rac-lactide |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |