CN104086758A - Method for preparing cellulose grafted lactide copolymer by using heating method - Google Patents
Method for preparing cellulose grafted lactide copolymer by using heating method Download PDFInfo
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- CN104086758A CN104086758A CN201410323342.7A CN201410323342A CN104086758A CN 104086758 A CN104086758 A CN 104086758A CN 201410323342 A CN201410323342 A CN 201410323342A CN 104086758 A CN104086758 A CN 104086758A
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Abstract
The invention discloses a method for preparing a cellulose grafted lactide copolymer by using a heating method, relates to a preparation method of a cellulose grafted lactide copolymer and aims at solving the technical problems that the preparation method of the existing cellulose grafted product adopts catalysts so that the cost is high. The preparation method of the cellulose grafted lactide copolymer comprises the following steps: adding cellulose into ionic liquid, heating and dissolving, then adding L-lactide, heating for reacting and subsequently obtaining a crude product, dissolving the crude product by using dimethyl sulfoxide, then centrifugally washing the crude product with ethyl alcohol or water and subsequently drying the crude product in vacuum to obtain the cellulose grafted lactide copolymer. The grafting ratio of the cellulose grafted lactide copolymer is 30%-80%; the product is pure and free from impurity element and can be applied to the field of degradable materials.
Description
Technical field
The present invention relates to the preparation method of cellulose graft lactide copolymer.
Background technology
Mierocrystalline cellulose is a kind of representative natural polysaccharide, and is organic substance the abundantest on the earth, and its structure is comprised of D-glucopyranose base (dehydration glucose).Its simple molecules formula is (C
6h
10o
5)
n.Mierocrystalline cellulose is a very important renewable resources, and it has many traditional application, as at furniture, and the aspects such as clothes and medical article.More than one since century, researchist is always by this charming attracting with continuable natural material, and carried out basis and the Practical Research of this material.Because concerning Mierocrystalline cellulose, due to the interaction of its intermolecular hydrogen bonding, it is very difficult expanding new application, thus still need to drop into sizable effort, to improve cellulosic workability.But due to Mierocrystalline cellulose self aggregated structure, be insoluble in common solvent, this attribute makes cellulosic solubility, functional grade is difficult to improve.Up to now, the solvent systems of dissolving cellulos only limited quantity is found, as the system in lithium chloride and N,N-dimethylacetamide (DMAc), ionic liquid etc.At < < colloid surface B: the research (The synthesis of biodegradable graft copolymer cellulose-graft – ploy (l-lactied) and the study of its controlled drug release) synthetic and medicament slow release effect of the article cellulose graft thing of the 26-33 page of bioelectric interface > > (Colloids and surfaces B:biointerfaces) 66 phases in 2008 discloses a kind of preparation method of cellulose graft product, the stannous octoate of take in ionic liquid at room temperature 1-allyl group 3-Methylimidazole villaumite (AmimCl) has synthesized cellulose graft product (cellulose-g-PLLA) as catalyzer passes through L-LROP graft reaction.In the method, adopt catalyzer, cause preparation cost high.
Summary of the invention
The present invention is that the preparation method that will solve existing cellulose graft product adopts catalyzer, the technical problem that cost is high, and a kind of method of utilizing heating method to prepare cellulose graft lactide copolymer is provided.
A kind of method of utilizing heating method to prepare cellulose graft lactide copolymer of the present invention, carry out according to the following steps:
One, take by ratio of weight and the number of copies the L-rac-Lactide of the Mierocrystalline cellulose of 1～5 part, the ionic liquid 1-butyl-3-methyl imidazolium villaumite of 50 parts ([Bmim] Cl) and 3～30 parts;
Two, Mierocrystalline cellulose step 1 being taken joins in ionic liquid, is heated to stir 12～24h at 70～100 ℃, obtains solution;
Three, L-rac-Lactide step 1 being taken adds in the solution of step 2 gained, is heated to stir 12～48h at 110～130 ℃, obtains crude product;
Four, by the crude product dmso solution of step 3 gained, then with after ethanol or water centrifuge washing, vacuum-drying 12～72h at 20～40 ℃, obtains cellulose graft lactide copolymer.
The present invention adopts lactide graft copolymerization in ionic liquid 1-allyl group 3-Methylimidazole villaumite in Mierocrystalline cellulose and L, and its reaction formula can be expressed as follows:
Preparation method's technical process of the present invention is simple, and raw material sources are wide, by the method for heating, make Mierocrystalline cellulose and rac-Lactide graft polymerization, saved the use of catalyzer raw material, make cost, the percentage of grafting of cellulose graft lactide copolymer is 30%～80%, and product is pure, inclusion-free element.And gained graft copolymer dissolves in the organic solvents such as dimethyl sulfoxide (DMSO), solved the problem that Mierocrystalline cellulose is insoluble in organic solvent, can be used for degradable material field, environmentally safe, Application Areas is extensive, good development prospect.
Accompanying drawing explanation
Fig. 1 is the cellulosic Fourier transform infrared spectroscopy figure described in test 1 step 1;
Fig. 2 is the Fourier transform infrared spectroscopy figure of the cellulose graft lactide copolymer of preparation in test 1;
Fig. 3 is the nuclear-magnetism carbon of the cellulose graft lactide copolymer of preparation in test 1
13c NMR spectrogram.
Fig. 4 is the Fourier transform infrared spectroscopy figure of the cellulose graft lactide copolymer of preparation in test 2.
Embodiment
Embodiment one: a kind of method of utilizing heating method to prepare cellulose graft lactide copolymer of present embodiment, carry out according to the following steps:
One, take by ratio of weight and the number of copies the L-rac-Lactide of the Mierocrystalline cellulose of 1～5 part, the ionic liquid 1-butyl-3-methyl imidazolium villaumite of 50 parts ([Bmim] Cl) and 3～30 parts;
Two, Mierocrystalline cellulose step 1 being taken joins in ionic liquid, is heated to stir 12～24h at 70～100 ℃, obtains solution;
Three, L-rac-Lactide step 1 being taken adds in the solution of step 2 gained, is heated to stir 12～48h at 110～130 ℃, obtains crude product;
Four, by the crude product dmso solution of step 3 gained, then with after ethanol or water centrifuge washing, vacuum-drying 12～72h at 20～40 ℃, obtains cellulose graft lactide copolymer.
Embodiment two: present embodiment is different from embodiment one is that L-rac-Lactide and cellulosic mass ratio in step 1 is (5～7): 1.Other is identical with embodiment one.
Embodiment three: what present embodiment was different from embodiment one or two is that the mode heating in step 2 is oil bath heating.Other is identical with embodiment one or two.
Embodiment four: what present embodiment was different from embodiment one or two is that the mode heating in step 2 is microwave heating.Other is identical with embodiment one or two.
Present embodiment adopts microwave heating, and under the effect of microwave, Mierocrystalline cellulose crystalline fracture, makes Mierocrystalline cellulose be transformed into cellulose Ⅱ from cellulose Ⅰ, and physical properties is closely similar but can be dissolved in ionic liquid faster and more.
Embodiment four: what present embodiment was different from embodiment one or two is that the mode heating in step 2 is Infrared Heating.Other is identical with embodiment one or two.
Present embodiment adopts Infrared Heating, and under ultrared effect, Mierocrystalline cellulose crystalline fracture, makes Mierocrystalline cellulose be transformed into cellulose Ⅱ from cellulose Ⅰ, and physical properties is closely similar but can be dissolved in ionic liquid faster and more.
Embodiment five: what present embodiment was different from one of embodiment one to four is to be heated in step 2 stir 18h at 90 ℃.Other is identical with one of embodiment one to four.
Embodiment six: what present embodiment was different from one of embodiment one to five is type of heating employing oil bath, microwave or the infrared heating mode in step 3.Other is identical with one of embodiment one to five.
Embodiment seven: what present embodiment was different from one of embodiment one to five is to be heated in step 3 stir 24h at 120 ℃.Other is identical with one of embodiment one to five.
Embodiment eight: present embodiment is different from one of embodiment one to five is that the rotating speed of centrifugal treating in step 4 is 6000r/min～8000r/min.Other is identical with one of embodiment one to five.
With following verification experimental verification beneficial effect of the present invention:
Test 1: the heating method of utilizing of this test is prepared the method for cellulose graft lactide copolymer, carries out according to the following steps:
One, take 0.4g Mierocrystalline cellulose, 20g ionic liquid 1-butyl-3-methyl imidazolium villaumite ([Bmim] Cl) and 1.8g L-rac-Lactide;
Two, Mierocrystalline cellulose step 1 being taken joins in ionic liquid, adopts oil bath to be heated to stirring and dissolving 12h at 100 ℃, obtains solution;
Three, L-rac-Lactide step 1 being taken adds in the solution of step 2 gained, and employing oil bath is stirred at heating 125 ℃, and reaction 24h, obtains crude product;
Four, by the crude product dmso solution of step 3 gained, then use after ethanol centrifuge washing 3 times, vacuum-drying 48h at 30 ℃, obtains cellulose graft lactide copolymer.
Cellulosic Fourier transform infrared spectroscopy figure (FTIR) described in this testing sequence one as shown in Figure 1.As shown in Figure 2, comparison diagram 1 and Fig. 2 can significantly find out the Fourier transform infrared spectroscopy figure of the cellulose graft lactide copolymer of preparing through step 4, and this graft copolymer has more a peak than cellulosic material, and position is at 1750cm
-1place, this absorption peak is the stretching vibration peak of C=O.This product of susceptible of proof is cellulose graft lactide copolymer.
The cellulose graft lactide copolymer that this test is prepared through step 4 is dissolved in the nuclear-magnetism carbon of surveying after dimethyl sulfoxide (DMSO) (DMSO)
13c NMR spectrogram as shown in Figure 3, as can be seen from Figure 3, has obvious peak at 40ppm place, the peak that this peak is DMSO.And at 17ppm, 21ppm, 66ppm, 69ppm, 170ppm, the peak of 174ppm represents respectively as shown in FIG. A3 in molecular formula, B3, A2, B2, B1, the carbon peak of A1, and cellulosic carbon peak is not obvious on figure, but on 80-105ppm position, have certain trend, thus, can confirm that this product is cellulose graft lactide copolymer.
This test is 9.8% by cellulosic dissolution rate in step 2.
The percentage of grafting of the cellulose graft lactide copolymer of this test preparation is 44.8%.
Test 2: the heating method of utilizing of this test is prepared the method for cellulose graft lactide copolymer, carries out according to the following steps:
One, take 0.4g Mierocrystalline cellulose, 20g ionic liquid 1-butyl-3-methyl imidazolium villaumite ([Bmim] Cl) and 1.8g L-rac-Lactide;
Two, Mierocrystalline cellulose step 1 being taken joins in ionic liquid, adopts stirring and dissolving 12h at microwave heating to 90 ℃, obtains solution;
Three, L-rac-Lactide step 1 being taken adds in the solution of step 2 gained, adopts oil bath to be heated to stir at 130 ℃, and reaction 48h, obtains crude product;
Four, by the crude product dmso solution of step 3 gained, then after water centrifuge washing 5 times, vacuum-drying 48h at 25 ℃, obtains cellulose graft lactide copolymer.
The Fourier transform infrared spectroscopy figure of the cellulose graft lactide copolymer of this test preparation as shown in Figure 4, as can be seen from Figure 4, at 1751cm
-1place obviously has more an absorption peak, and the absorption intensity at peak is very large, the stretching vibration peak that this absorption peak is C=O, in this figure, the absorption intensity at peak and the absorption intensity of Fig. 2 are compared, intensity is larger, and the increase along with the reaction times is described, the intensity at overall absorption peak is also increasing.From then on this product of absorption peak susceptible of proof of C=O is cellulose graft lactide copolymer.
This test is 15.7% by cellulosic dissolution rate in step 2.This is that Mierocrystalline cellulose crystalline fracture, makes Mierocrystalline cellulose be transformed into cellulose Ⅱ from cellulose Ⅰ, and cellulosic solubleness is improved greatly because under microwave action, for improving percentage of grafting, lays the foundation.
The percentage of grafting of the cellulose graft lactide copolymer of this test preparation is 61.2%.The high percentage of grafting of this product improves its solubilized performance, dissolves in and in solvent, carries out spinning.
Test 3: the heating method of utilizing of this test is prepared the method for cellulose graft lactide copolymer, carries out according to the following steps:
One, take 0.5g Mierocrystalline cellulose, 25g ionic liquid 1-butyl-3-methyl imidazolium villaumite ([Bmim] Cl) and 1.9g L-rac-Lactide;
Two, Mierocrystalline cellulose step 1 being taken joins in ionic liquid, adopts stirring and dissolving 12h at microwave heating to 80 ℃, obtains solution;
Three, L-rac-Lactide step 1 being taken adds in the solution of step 2 gained, adopts at microwave heating to 120 ℃ and stirs, and reaction 12h, obtains crude product;
Four, by the crude product dmso solution of step 3 gained, then use after ethanol centrifuge washing 5 times, vacuum-drying 24h at 20 ℃, obtains cellulose graft lactide copolymer.
This test is 15.1% by cellulosic dissolution rate in step 2.
The percentage of grafting of the cellulose graft lactide copolymer of this test preparation is 75.5%.
Test 4: the heating method of utilizing of this test is prepared the method for cellulose graft lactide copolymer, carries out according to the following steps:
One, take 0.5g Mierocrystalline cellulose, 20g ionic liquid 1-butyl-3-methyl imidazolium villaumite ([Bmim] Cl) and L-rac-Lactide; Wherein L-rac-Lactide and cellulosic mass ratio (1～30): 1, ionic liquid 1-butyl-3-methyl imidazolium villaumite ([Bmim] Cl) is (5～50) with cellulosic mass ratio: 1;
Two, Mierocrystalline cellulose step 1 being taken joins in ionic liquid, adopts stirring and dissolving 8h at microwave heating to 100 ℃, obtains solution;
Three, L-rac-Lactide step 1 being taken adds in the solution of step 2 gained, adopts at Infrared Heating to 130 ℃ and stirs, and reaction 12h, obtains crude product;
Four, by the crude product dmso solution of step 3 gained, then use after ethanol centrifuge washing 5 times, vacuum-drying 24h at 40 ℃, obtains cellulose graft lactide copolymer.
The percentage of grafting of the cellulose graft lactide copolymer of this test preparation is 71.9%.The high percentage of grafting of this product improves its solubilized performance, dissolves in and in solvent, carries out spinning.
Claims (9)
1. utilize heating method to prepare a method for cellulose graft lactide copolymer, it is characterized in that the method carries out according to the following steps:
One, take by ratio of weight and the number of copies the Mierocrystalline cellulose of 1～5 part, 1-butyl-3-Methylimidazole villaumite ionic liquid of 50 parts and the L-rac-Lactide of 3～30 parts;
Two, Mierocrystalline cellulose step 1 being taken joins in 1-butyl-3-Methylimidazole villaumite ionic liquid, is heated to stir 12～24h at 70～100 ℃, obtains solution;
Three, L-rac-Lactide step 1 being taken adds in the solution of step 2 gained, is heated to stir 12～48h at 110～130 ℃, obtains crude product;
Four, by the crude product dmso solution of step 3 gained, then with after ethanol or water centrifuge washing, vacuum-drying 12～72h at 20～40 ℃, obtains cellulose graft lactide copolymer.
2. a kind of method of utilizing heating method to prepare cellulose graft lactide copolymer according to claim 1, is characterized in that L-rac-Lactide and the cellulosic mass ratio in step 1 is (5～7): 1.
3. a kind of method of utilizing heating method to prepare cellulose graft lactide copolymer according to claim 1 and 2, is characterized in that the mode heating in step 2 is oil bath heating.
4. a kind of method of utilizing heating method to prepare cellulose graft lactide copolymer according to claim 1 and 2, is characterized in that the mode heating in step 2 is microwave heating.
5. a kind of method of utilizing heating method to prepare cellulose graft lactide copolymer according to claim 1 and 2, is characterized in that the mode heating in step 2 is Infrared Heating.
6. a kind of method of utilizing heating method to prepare cellulose graft lactide copolymer according to claim 1 and 2, is characterized in that being heated to stir 18h at 90 ℃ in step 2.
7. a kind of method of utilizing heating method to prepare cellulose graft lactide copolymer according to claim 1 and 2, is characterized in that the type of heating in step 3 adopts oil bath, microwave or infrared heating mode.
8. a kind of method of utilizing heating method to prepare cellulose graft lactide copolymer according to claim 1 and 2, is characterized in that being heated to stir 24h at 120 ℃ in step 3.
9. a kind of method of utilizing heating method to prepare cellulose graft lactide copolymer according to claim 1 and 2, the rotating speed that it is characterized in that centrifugal treating in step 4 is 6000r/min～8000r/min.
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| CN104231236A (en) * | 2014-10-10 | 2014-12-24 | 黑龙江大学 | Method for utilizing ionic liquid to synthesize lactide and cellulose graft copolymer |
| CN104231089A (en) * | 2014-10-10 | 2014-12-24 | 黑龙江大学 | Method for modifying cellulose lactic acid in ionic liquid |
| CN104341531A (en) * | 2014-10-10 | 2015-02-11 | 黑龙江大学 | Method for preparing cellulose lactide derivatives by virtue of ionic liquid |
| CN106397744A (en) * | 2016-09-20 | 2017-02-15 | 广东省生物工程研究所（广州甘蔗糖业研究所） | Bagasse graft lactide copolymer and method for preparing same |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104231236A (en) * | 2014-10-10 | 2014-12-24 | 黑龙江大学 | Method for utilizing ionic liquid to synthesize lactide and cellulose graft copolymer |
| CN104231089A (en) * | 2014-10-10 | 2014-12-24 | 黑龙江大学 | Method for modifying cellulose lactic acid in ionic liquid |
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| CN106397744A (en) * | 2016-09-20 | 2017-02-15 | 广东省生物工程研究所（广州甘蔗糖业研究所） | Bagasse graft lactide copolymer and method for preparing same |
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Application publication date: 20141008 |