CN100494245C - Preparation method of functional polyester containing malic acid unit by biological catalyst - Google Patents

Preparation method of functional polyester containing malic acid unit by biological catalyst Download PDF

Info

Publication number
CN100494245C
CN100494245C CNB2006100341196A CN200610034119A CN100494245C CN 100494245 C CN100494245 C CN 100494245C CN B2006100341196 A CNB2006100341196 A CN B2006100341196A CN 200610034119 A CN200610034119 A CN 200610034119A CN 100494245 C CN100494245 C CN 100494245C
Authority
CN
China
Prior art keywords
malic acid
functional polyester
acid unit
lipase
biocatalysis
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.)
Expired - Fee Related
Application number
CNB2006100341196A
Other languages
Chinese (zh)
Other versions
CN1939952A (en
Inventor
李光吉
姚大虎
宗敏华
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
South China University of Technology SCUT
Original Assignee
South China University of Technology SCUT
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by South China University of Technology SCUT filed Critical South China University of Technology SCUT
Priority to CNB2006100341196A priority Critical patent/CN100494245C/en
Publication of CN1939952A publication Critical patent/CN1939952A/en
Application granted granted Critical
Publication of CN100494245C publication Critical patent/CN100494245C/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Abstract

Biological catalytic production of functional polyester containing malic acid unit is carried out by taking diatomic alcohol and malic acid as monomers, and condensation polymerizing diatomic alcohol catalyzed by lipase with malic acid to obtain the final product. It's simple selective and controllable, has gentle reactive condition and better performances.

Description

The biocatalysis preparation contains the method for the functional polyester of malic acid unit
Technical field
The invention belongs to the synthetic and chemical field of biocatalysis, be specifically related to contain the method for the functional polyester of malic acid unit by the direct polymerization prepared in reaction of biocatalysis.
Background technology
The functional polyester that contains malic acid unit has good biocompatibility, modifiability and biodegradable performance, and its degraded product is harmless.Can adjust the The Nomenclature Composition and Structure of Complexes of polymkeric substance by adjusting the unitary ratio of different structure that constitutes this polymer macromolecule chain, thereby adjust its physicochemical property.Studies show that: the functional polyester that contains malic acid unit has wide application prospect at medicine, environmental protection, novel material, bioengineering field, for example, can be used as the coating material or the like of timbering material, the operating sutures of the intravital medicament slow release pharmaceutical carrier of people, bone repair, tissue, green molecules surfactant, medicine.
At present, traditional chemical process is mainly adopted in the preparation that contains the functional polyester of malic acid unit.General available organometallic compound is a catalyzer, at first carboxyl in the oxysuccinic acid monomer or hydroxyl is carried out chemoproection, carries out catalyzed polymerization then, sloughs blocking group at last, obtains subject polymer.Therefore, the chemical process preparation contains the functional polyester of malic acid unit, and reactions steps is more, and yield is lower, severe reaction conditions (high temperature, high vacuum), and cost is also just than higher.On the other hand, owing to have to use a large amount of organic solvents and deleterious organo-metallic catalyst in the reaction process, so can bring than the serious environmental pollution problem, the toxicity that is difficult to the residual chemicals of removing in the product has then greatly limited the functional polyester that contains malic acid unit of chemical method preparation and has used in biotechnology and field of medicaments.The synthetic report that removes to prepare the functional polyester that contains oxysuccinic acid of also useful microorganism.This method be utilize some special moulds, slime mould cell in process of growth, can be that carbon source is synthesized polymalic acid with oligose (as D-glucose, fructose, sucrose, succsinic acid etc.).The polymalic acid molecular weight that the microorganism synthesis method makes is higher, and product is purer; Yet the productive rate of this method is lower, the product separation difficulty, and cost is higher, and product structure is single, only can synthesize Beta-polymalic acid at present, also is difficult to obtain the functional polyester that contains malic acid unit of other structure, thereby has limited its research widely and used.Therefore, explore the novel method, the new theory that prepare the functional polyester that contains malic acid unit and have important Research Significance and wide application prospect.
Summary of the invention
The objective of the invention is to problem, provide a kind of biocatalysis preparation to contain the novel method of the functional polyester of malic acid unit at the technical matters existence of existing chemosynthesis approach.This method reaction conditions gentleness, less energy consumption, productive rate height, selectivity is good and product is easily separated.Because reaction system is simple, do not use deleterious organo-metallic catalyst simultaneously, solvent consumption is less, and reaction process has the environmental friendliness feature, and product is purer, and is safe.
Purpose of the present invention is achieved through the following technical solutions:
A kind of biocatalysis preparation contains the method for the functional polyester of malic acid unit, is monomer with dibasic alcohol and oxysuccinic acid, utilizes the direct polymerization reaction of lipase-catalyzed dibasic alcohol and oxysuccinic acid, prepares the functional polyester that contains malic acid unit.Described lipase derives from Candiada antarctica, Thermonvces lanuginosus, Rhizomucor miehei, Mucor miehei or derives from the lipase (PPL) of pig pancreas.The monomer of this method also preferably includes diprotic acid.The carbon chain lengths of described dibasic alcohol is C2~C16, and the carbon chain lengths of diprotic acid is C4~C12.
For further realizing purpose of the present invention, the method that described a kind of biocatalysis preparation contains the functional polyester of malic acid unit is dibasic alcohol and oxysuccinic acid to be added in the reactor according to 1: 2~2: 1 molar ratio mix, be heated to 40~120 ℃, in lipase with adding the monomer total amount than adding lipase for the ratio of 1004000U/g, in magnetic agitation speed is 20~400rpm, vacuum tightness is under the condition of 1~100mmHg, react after 12~96 hours, separate the functional polyester that obtains containing malic acid unit.
The method that described a kind of biocatalysis preparation contains the functional polyester of malic acid unit also preferably adds dibasic alcohol and the oxysuccinic acid molar ratio according to 1: 2~20: 1 in the reactor, add diprotic acid simultaneously, with the ratio of adjusting carboxyl and hydroxyl in the reaction system in 3: 2~1: 1 scope, mixing also is heated to 40~120 ℃, in lipase with adding the monomer total amount add lipase than the ratio that is 100~4000U/g, magnetic agitation speed is at 20~400rpm, vacuum tightness is under the condition of 1~100mmHg, react after 12~96 hours, separate the functional polyester that obtains containing malic acid unit.
Preferred 50~the 300rpm of above-mentioned stirring velocity, the vacuum tightness of reaction system is preferably 5~80mmHg.
Described separation method is: reaction mixture passes through dissolution with solvents, removes by filter lipase, and rotary evaporation removes and desolvates then, carries out drying under vacuum, makes the functional polyester that contains malic acid unit, and described solvent is a chloroform.
The method that biocatalysis preparation of the present invention contains the functional polyester of malic acid unit is to adopt to have the chirality diprotic acid of hydroxyl on dibasic alcohol, diprotic acid and the asymmetric c atom---oxysuccinic acid is a monomer, utilize the condensation polymerization reaction of lipase-catalyzed acid and alcohol, polymerization obtains the functional polyester that contains malic acid unit of different structure.
Principle of the present invention: the present invention adopts and contains unsymmetrical carbon, and one of monomer that the special diprotic acid-oxysuccinic acid that has hydroxyl on the unsymmetrical carbon reacts as condensation polymerization, direct polymerization under lipase-catalyzed condition is introduced the polyester macromolecule main chain with malic acid unit.Because the oxysuccinic acid molecule has a hydroxyl and two carboxyls, therefore can on the main chain of polyester, introduce functional group, thereby obtain containing the functional polyester of malic acid unit.The present invention also can introduce diprotic acid in monomer system, diprotic acid can be adjusted the The Nomenclature Composition and Structure of Complexes of polymer chain, in in a big way, change the various performances (for example: but mechanical property, second-order transition temperature, fusing point, wetting ability, biocompatibility, biodegradable bioresorbable or the like) of the functional polyester contain malic acid unit, satisfy the performance requriements under the different service conditions better.
The present invention has following advantage compared with prior art:
1, adopts efficiently that biological catalyst lipase prepares the functional polyester that contains malic acid unit, overcome that the traditional chemical method steps is many, severe reaction conditions, shortcoming that by product is many, be expected to reduce preparation cost.
2, owing to adopt the direct polymerization reaction system of biocatalysis, do not need to use deleterious organo-metallic catalyst and a large amount of organic solvent, overcome the shortcoming that traditional chemical process product is difficult for purifying, thereby reaction product has higher security.
3, the reaction of the direct polymerization of biocatalysis is compared with traditional chemical process, the reaction conditions gentleness, and reaction process is simple, controlled, environmental friendliness.
Description of drawings
Fig. 1 is the infrared spectrum of the obtained product of comparative example;
Fig. 2 is the infrared spectrum of embodiment 1 obtained product;
Fig. 3 is the H NMR spectrogram of embodiment 1 obtained product.
Embodiment
The invention will be further described below in conjunction with specific embodiment, but the present invention's scope required for protection is not limited to the related scope of embodiment.
Embodiment 1
With butyleneglycol, hexanodioic acid, oxysuccinic acid according to 15: 13: 2 ratios of mol ratio, add at the bottom of the garden of 100mL in the flask (ratio of carboxyl and hydroxyl is 16: 15), add the lipase that derives from Candida antarctica by the every gram monomer of 1000U/, place under 70 ℃ of oil baths, magnetic agitation speed is 200rpm, vacuum tightness is 20mmHg, react after 48 hours, add the chloroform lysate, remove by filter lipase, product solution for vacuum Rotary drying, molecular weight is 12400 polymkeric substance.
Embodiment 2
Butyleneglycol, hexanodioic acid, oxysuccinic acid are added according to 15: 7.5: 7.5 ratios of mol ratio at the bottom of the garden of 100mL in the flask (ratio of carboxyl and hydroxyl is 5: 4), add the lipase that derives from Candida antarctica by the every gram monomer of 1500U/, place under 80 ℃ of oil baths, magnetic agitation speed is 200rpm, and vacuum tightness is 20mmHg, reacts after 96 hours, add the chloroform lysate, remove by filter lipase, product solution for vacuum Rotary drying, molecular weight is 6400 polymkeric substance.
Embodiment 3
Ethylene glycol, hexanodioic acid, oxysuccinic acid are added according to 15: 13: 2 ratios of mol ratio at the bottom of the garden of 100mL in the flask (ratio of carboxyl and hydroxyl is 16: 15), add the lipase that derives from Candida antarctica by the every gram monomer of 4000U/, place under 40 ℃ of oil baths, magnetic agitation speed is 200rpm, and vacuum tightness is 1mmHg, reacts after 48 hours, add the chloroform lysate, remove by filter lipase, product solution for vacuum Rotary drying, molecular weight is 4600 polymkeric substance.
Embodiment 4
Hexylene glycol, hexanodioic acid, oxysuccinic acid are added according to 15: 13: 4 ratios of mol ratio at the bottom of the garden of 100mL in the flask (ratio of carboxyl and hydroxyl is 1: 1), add the lipase that derives from Candida antarctica by the every gram monomer of 1500U/, place under 70 ℃ of oil baths, magnetic agitation speed is 200rpm, and vacuum tightness is 20mmHg, reacts after 48 hours, add the chloroform lysate, remove by filter lipase, product solution for vacuum Rotary drying, molecular weight is 14000 polymkeric substance.
Embodiment 5
Ethohexadiol, hexanodioic acid, oxysuccinic acid are added according to 15: 13: 2 ratios of mol ratio at the bottom of the garden of 100mL in the flask (ratio of carboxyl and hydroxyl is 16: 15), add the lipase that derives from Candid antarctica by the every gram monomer of 100U/, place under 80 ℃ of oil baths, magnetic agitation speed is 400rpm, and vacuum tightness is 100mmHg, reacts after 48 hours, add the chloroform lysate, remove by filter lipase, product solution for vacuum Rotary drying, molecular weight is 8200 polymkeric substance.
Embodiment 6
Ethohexadiol, hexanodioic acid, oxysuccinic acid are added according to 15: 2: 12 ratios of mol ratio at the bottom of the garden of 100mL in the flask (ratio of carboxyl and hydroxyl is 3: 2), add the lipase that derives from Candida antarctica by the every gram monomer of 1500U/, place under 70 ℃ of oil baths, magnetic agitation speed is 200rpm, and vacuum tightness is 20mmHg, reacts after 48 hours, add the chloroform lysate, remove by filter lipase, product solution for vacuum Rotary drying, molecular weight is 2000 polymkeric substance.
Embodiment 7
Ethohexadiol, oxysuccinic acid are added according to 1: 1 ratio of mol ratio at the bottom of the garden of 100mL in the flask, add the lipase that derives from Candida antarctica by the every gram monomer of 2500U/, place under 80 ℃ of oil baths, magnetic agitation speed is 20rpm, and vacuum tightness is 20mmHg, reacts after 48 hours, add the tetrahydrofuran (THF) lysate, remove by filter lipase, product solution for vacuum Rotary drying, molecular weight is 2000 polymkeric substance.
Embodiment 8
Ethylene glycol, hexanodioic acid, oxysuccinic acid are added according to 2: 1: 1 ratios of mol ratio at the bottom of the garden of 100mL in the flask (ratio of carboxyl and hydroxyl is 5: 4), add the lipase that derives from Candida antarctica by the every gram monomer of 2000U/, place under 60 ℃ of oil baths, magnetic agitation speed is 200rpm, and vacuum tightness is 20mmHg, reacts after 12 hours, add the acetone solution product, remove by filter lipase, product solution for vacuum Rotary drying, molecular weight is 3000 polymkeric substance.
Embodiment 9
Ethohexadiol, hexanodioic acid, oxysuccinic acid are added according to 15: 13: 2 ratios of mol ratio at the bottom of the garden of 100mL in the flask (ratio of carboxyl and hydroxyl is 16: 15), add the lipase that derives from Mucor miehei by the every gram monomer of 1500U/, place under 70 ℃ of oil baths, magnetic agitation speed is 200rpm, and vacuum tightness is 20mmHg, reacts after 48 hours, add the chloroform lysate, remove by filter lipase, product solution for vacuum Rotary drying, molecular weight is 3000 polymkeric substance.
Embodiment 10
Ethohexadiol, hexanodioic acid, oxysuccinic acid are added according to 15: 13: 2 ratios of mol ratio at the bottom of the garden of 100mL in the flask (ratio of carboxyl and hydroxyl is 16: 15), add the lipase that derives from PPL by the every gram monomer of 1500U/, place under 110 ℃ of oil baths, magnetic agitation speed is 200rpm, and vacuum tightness is 20mmHg, reacts after 48 hours, add the chloroform lysate, remove by filter lipase, product solution for vacuum Rotary drying, molecular weight is 13000 polymkeric substance.
Embodiment 11
Ethylene glycol, dodecanedioic acid, oxysuccinic acid are added according to 15: 10: 5 ratios of mol ratio at the bottom of the garden of 100mL in the flask (ratio of carboxyl and hydroxyl is 7: 6), add the lipase that derives from PPL by the every gram monomer of 1500U/, place under 110 ℃ of oil baths, magnetic agitation speed is 200rpm, and vacuum tightness is 20mmHg, reacts after 48 hours, add the chloroform lysate, remove by filter lipase, product solution for vacuum Rotary drying, molecular weight is 3100 polymkeric substance.
Embodiment 12
N-Hexadecane glycol, Succinic Acid, oxysuccinic acid are added according to 15: 9: 6 ratios of mol ratio at the bottom of the garden of 100mL in the flask (ratio of carboxyl and hydroxyl is 6: 5), add the lipase that derives from PPL by the every gram monomer of 1500U/, place under 120 ℃ of oil baths, magnetic agitation speed is 200rpm, and vacuum tightness is 20mmHg, reacts after 48 hours, add the chloroform lysate, remove by filter lipase, product solution for vacuum Rotary drying, molecule is 5800 polymkeric substance.
The comparative example
Butyleneglycol, hexanodioic acid are added according to 1: 1 ratio of mol ratio at the bottom of the garden of 100mL in the flask, add the lipase that derives from Candida atarctica by the every gram monomer of 1000U/, place under 70 ℃ of oil baths, magnetic agitation speed is 200rpm, and vacuum tightness is 20mmHg, reacts after 48 hours, add the chloroform lysate, remove by filter lipase, product solution for vacuum Rotary drying, molecular weight is 14200 polymkeric substance.
Product analysis:
Carry out product analysis with embodiment 1 prepared product.
1, Infrared spectroscopy
Testing method: sample was descended dry 24 hours 50 ℃ of vacuum drying ovens, use the pellet technique sample preparation, measure with the German Bruker VECTOR of company 33 type infrared spectrometers.
Fig. 1 is the infrared spectrum of the obtained product of comparative example; Fig. 2 is the infrared spectrum of embodiment 1 obtained product.Contrast infrared spectrum illustrated in figures 1 and 2, discovery is on the infrared spectrum of the terpolymer of butyleneglycol, hexanodioic acid and oxysuccinic acid, at 3500cm -1Near tangible hydroxyl absorption peak has appearred.This explanation has correspondingly been introduced hydroxyl introduce oxysuccinic acid in comonomer after on polymer molecular chain, obtained having the functional polyester of hydroxyl.
2, H NMR analyzes
Testing method: sample was descended dry 24 hours 50 ℃ of vacuum drying ovens, was solvent with the deuterochloroform, measured with the German Bruker Ultrashied of company 400 type nuclear magnetic resonance analyser.
Fig. 3 is the H NMR spectrogram of embodiment 1 thing that guides.H NMR spectrogram according to the terpolymer of as shown in Figure 3 butyleneglycol, hexanodioic acid and oxysuccinic acid, the absorption peak that the molecular formula of polymkeric substance and different C go up H from Fig. 3 is as can be seen: near near near the absorption peak that has occurred having occurred the absorption peak, 3.7ppm of H on the malic acid unit achirality C having occurred the absorption peak, 4.5ppm of H on the hydroxyl of malic acid unit H on the malic acid unit chirality C chemical shift is 2.8ppm, thereby proof has been introduced malic acid unit in polymer chain, obtained containing the functional polyester of malic acid unit.

Claims (8)

1, a kind of biocatalysis preparation contains the method for the functional polyester of malic acid unit, it is characterized in that with dibasic alcohol and oxysuccinic acid be monomer, utilize the direct polymerization reaction of lipase-catalyzed dibasic alcohol and oxysuccinic acid, prepare the functional polyester that contains malic acid unit; Described lipase derives from antarctic candida (Candida Antarctica), the thermophilic hyphomycete of cotton shape (Thermomyces lanuginosus), head mold (Rhizomucor miehei), the conspicuous Mucor (Mucor miehei) of rice or derives from the lipase (PPL) of pig pancreas.
2, prepare the method for the functional polyester that contains malic acid unit according to the described a kind of biocatalysis of claim 1, it is characterized in that described monomer also comprises the diprotic acid except that oxysuccinic acid.
3, a kind of biocatalysis preparation according to claim 1 contains the method for the functional polyester of malic acid unit, it is characterized in that dibasic alcohol and oxysuccinic acid added in the reactor according to 1: 2~2: 1 molar ratio and mix, be heated to 40~120 ℃, in lipase with adding the monomer total amount add lipase than the ratio that is 100~4000U/g, in magnetic agitation speed is 20~400rpm, vacuum tightness is under the condition of 1~100mmHg, react after 12~96 hours, separate the functional polyester that obtains containing malic acid unit.
4, a kind of biocatalysis preparation according to claim 2 contains the method for the functional polyester of malic acid unit, it is characterized in that it being that dibasic alcohol and the oxysuccinic acid molar ratio according to 1: 2~20: 1 is added in the reactor, add the diprotic acid except that oxysuccinic acid simultaneously, with the ratio of adjusting carboxyl and hydroxyl in the reaction system in 3: 2~1: 1 scope, mixing also is heated to 40~120 ℃, in lipase with adding the monomer total amount add lipase than the ratio that is 100~4000U/g, magnetic agitation speed is at 20~400rpm, vacuum tightness is under the condition of 1~100mmHg, react after 12~96 hours, separate the functional polyester that obtains containing malic acid unit.
5, contain the method for the functional polyester of malic acid unit according to claim 2 or 4 described a kind of biocatalysis preparations, it is characterized in that the carbon chain lengths of described dibasic alcohol is C2~C16, the carbon chain lengths of the diprotic acid except that oxysuccinic acid is C4~C12.
6, the method that contains the functional polyester of malic acid unit according to claim 3 or 4 described a kind of biocatalysis preparations is characterized in that low whipping speed is to react under the condition of 50~300rpm, and the vacuum tightness of reaction system is 5~80mmHg.
7, the method that contains the functional polyester of malic acid unit according to claim 3 or 4 described a kind of biocatalysis preparations, it is characterized in that, described separation method is: reaction mixture passes through dissolution with solvents, removes by filter lipase, rotary evaporation removes and desolvates then, under vacuum, carry out drying, make the functional polyester that contains malic acid unit.
8, a kind of biocatalysis preparation according to claim 7 contains the method for the functional polyester of malic acid unit, it is characterized in that described solvent is chloroform, acetone or tetrahydrofuran (THF).
CNB2006100341196A 2006-03-08 2006-03-08 Preparation method of functional polyester containing malic acid unit by biological catalyst Expired - Fee Related CN100494245C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CNB2006100341196A CN100494245C (en) 2006-03-08 2006-03-08 Preparation method of functional polyester containing malic acid unit by biological catalyst

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CNB2006100341196A CN100494245C (en) 2006-03-08 2006-03-08 Preparation method of functional polyester containing malic acid unit by biological catalyst

Publications (2)

Publication Number Publication Date
CN1939952A CN1939952A (en) 2007-04-04
CN100494245C true CN100494245C (en) 2009-06-03

Family

ID=37958497

Family Applications (1)

Application Number Title Priority Date Filing Date
CNB2006100341196A Expired - Fee Related CN100494245C (en) 2006-03-08 2006-03-08 Preparation method of functional polyester containing malic acid unit by biological catalyst

Country Status (1)

Country Link
CN (1) CN100494245C (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109251942A (en) * 2018-09-17 2019-01-22 北京化工大学 A kind of method of lipase-catalyzed synthesis itaconic acid polyester

Also Published As

Publication number Publication date
CN1939952A (en) 2007-04-04

Similar Documents

Publication Publication Date Title
Liu et al. Controlled synthesis of polypeptides
CN109879992B (en) Application of para-phenyl-containing alpha-diimine nickel (II) complex in catalyzing 3-heptene chain walking polymerization
CN101721944A (en) Polymer-base carbon nanotube dispersing auxiliary, synthesis method and application thereof
CN110437426B (en) Brush copolymer and preparation method thereof
CN111592644A (en) Ring-opening polymerization method for cyclic monomer
CN107459505B (en) Fluorescent functional carbonate, preparation method and application thereof, and fluorescent polycarbonate prepared from fluorescent functional carbonate
CN101041711B (en) Method for preparing malic acid containing unit functional polyester by biological catalysis in organic medium
CN1974605A (en) Synthesis process of beta-cyclodextrin-poly-L-glutamic acid-benzyl ester grafted copolymer
CN100494245C (en) Preparation method of functional polyester containing malic acid unit by biological catalyst
CN102408553B (en) Synthesis technology of biodegradable polylactic acid-glutamic acid for medical use
CN108503803B (en) A method of poly- γ-fourth lactones is prepared using urea/alkoxide
CN106496538B (en) Synthesis method of high molecular weight polycaprolactone
CN100384883C (en) Method for preparing chitose graft polycaprolactone
CN112608472A (en) Terminal functionalized polymer and method for carrying out CuAAC polymerization by utilizing copper acetylide
CN110092849B (en) Cationic chain transfer agent and application thereof
CN109485840B (en) Method for catalyzing lactide polymerization by using amine imine magnesium complex
CN110563941B (en) Preparation method of medical biodegradable high polymer material polycaprolactone
CN113061210B (en) Janus type star polymer with circular polarization fluorescence
CN107057047B (en) The brush polymer of method and preparation based on poly- (N- heterocycle carbine) structure self-catalysis self-initiating open loop synthesis brush polymer
CN114807252A (en) Method for synthesizing four-arm star polylactic acid in supercritical carbon dioxide
CN109880110B (en) Poly (2-vinylpyridine) -containing polypeptide block copolymer and preparation method and application thereof
Xu et al. Chain-end functionalization of living helical polyisocyanides through a Pd (II)-mediated Sonogashira coupling reaction
CN1169863C (en) Superbranched polyquaternary ammonium salt and its preparation method
CN105985516B (en) Synthesis and application of bifunctional initiator with near-infrared absorption and self-sorting polymerization characteristics
CN101085837A (en) Star-type polymer using fullerene derivative as core and preparation method thereof

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
C17 Cessation of patent right
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20090603

Termination date: 20120308