CN101328267A - Biodegradable polyamideimide and preparation thereof - Google Patents
Biodegradable polyamideimide and preparation thereof Download PDFInfo
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- CN101328267A CN101328267A CNA2008100637029A CN200810063702A CN101328267A CN 101328267 A CN101328267 A CN 101328267A CN A2008100637029 A CNA2008100637029 A CN A2008100637029A CN 200810063702 A CN200810063702 A CN 200810063702A CN 101328267 A CN101328267 A CN 101328267A
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Abstract
The invention discloses a biodegradable poly(citric amide imide) and a preparation method thereof, which belong to the polymer material technical field. Citrate ester and aliphatic diamine are evenly mixed according to the mol ratio of between 1 to 0.2 and 1 to 5, a catalyst which accounts for 1 to 10 weight percent of the total weight of the citrate ester is added and evenly mixed with reactants, and a condensation polymerization reaction is performed for 1 to 6 hours at vacuum pressure reduction and a temperature of between 50 and 100 DEG C to form a prepolymer; and the prepolymer continues to react for 10 to 24 hours at a temperature of between 50 and 160 DEG C to produce the crosslinking network type biodegradable poly(citric amide imide). The preparation method has the advantages of easy degradation and environmental protection.
Description
Technical field
The present invention relates to a kind of Biodegradable Polymers---poly-citric amide imide and preparation method thereof, belong to the macromolecular compound technical field, its product is mainly used in environment-friendly material and biomedical material.
Technical background
How polyamide material is given excellent biological compatibility and with physical environment close friend's performance, people such as thread Fang Zhi have proposed first by diethyl tartrate and the hexanediamine polyamide resin [J.Polym.Sci. that synthesis hydrophilic is good quickly and easily, Polym.Chem.Ed.1975,13,179; J.Polym.Sci.Polym.Chem.Ed., 1980,18 (3), 939-948].This polyreaction will be carried out under suitable polar solvent condition, as methyl-sulphoxide, N,N-DIMETHYLACETAMIDE or methyl alcohol etc.The aggregated structure of this winestone acid type polyamide resin and degradation property had had more improvement and deep research [U.S. Pat 5505784 and US5613494 afterwards again; People such as A.Alla, Polymer, 2005,46 (9), 2854-2861].Hoagland had found a reaction [P.D.Hoagland, Carbohydrate Res.1981,98,203-208] of similarly synthesizing polycondensate by tetrahydroxyadipic acid diethyl ester and quadrol again in 1981.Subsequently people such as Kiely to disclose with glucaric acid and fats diamines be the method [U.S. Pat 6894135 that raw material forms the poly-dextrose acid amides; J.Am.Chem.Soc.1994,116,511-518; J.Polym.Sci., PartA:Polym.Chem., 2000,38,594-603.].It is synthetic polylysine citric amide of raw material and the test that is applied to pharmaceutical carrier that people such as Vert have proposed with citric acid and Methionin, but the complicated [U.S. Pat 5026821 of synthesis step harshness; Euro.J.Pharm.Sci., 1998,6,61-73; J.Polym.Sci., PartA:Polym.Chem., 2001,39,3475-3484], the poly-imido molecular weight of citric amide of gained linear pattern has only several thousand to 30,000, and productive rate is also lower, and machine-shaping difficulty and cost are big.
Also have many people to adopt the method that forms the amide-ester multipolymer, for example: Chinese patent 200410040071.0; Chinese patent 200510020549.8; Chinese patent 99114951.3; Chinese patent 98121899.7; Chinese patent 99115200.X; Chinese patent 00112699.7; Chinese patent 00112700.4; Chinese patent 200710064535.5; U.S. Pat 5457144 proposes to obtain the method that main chain contains the polymeric amide of ester group with nylon and pet reaction; People such as Gonsalves, Macromolecules, 1992,25 (12), 3309-3312; Zhang Hailian, Wang Lu, Qian Zhiyong, Liu Xiaobo, synthetic resins and plastics .2003,20 (6), 10-12.Guo and Chu propose to reach biodegradability [Biomacromolecules, 2007,8,2851-2861] with containing the polyether ester amides structure.
General big kind polymeric amide (all kinds of nylon) is a raw material with non-renewable resource, the methylene radical of carboxylic moiety
Wetting ability is very poor, and the good orderly regular accumulation of adding between the macromolecular chain makes nylon often be difficult to by biological by way of degraded.Have only the white-rot fungi of the very strong oxidisability of degradation capability just to work.Therefore, there are many people once to carry out foregoing some kinds of trials all the time, designed different schemes to scheme to improve the degraded of polymeric amide, existing main technical schemes may be summarized to be: (a) partly introduce two or more hydroxyls at di-carboxylic acid, as, replace Succinic Acid with tartrate, glucaric acid replaces hexanodioic acid; (b) introduce complicated side group,, reduce the degree of order as substituted-amino or raising Zhi Liandu; (c) introducing polyester segment in the polyamide structure forms multipolymer or uses dibasic alcohol with and poly-(ester-acid amide) multipolymer of amino acid formation.
Applying of degradable polyamide material can substitute many already present plastics, rubber and fibre product at present, becomes the material to eco-friendly.Can expect that they can also will be applied to numerous areas as the business development of poly(lactic acid), as the commodity packaging material, agricultural mulching, biomedical material, pharmaceutical carrier, sanitary tool, non-woven fabrics, or the like.Therefore, develop a kind of biodegradable novel polyamide material, for reducing nondegradable white pollution, promoting the Sustainable development of environment protection and society to have using value.
Summary of the invention
The purpose of this invention is to provide a kind of Biodegradable polyamideimide and preparation method thereof.
The technical scheme that the present invention takes for achieving the above object is as follows, a kind of Biodegradable polyamideimide, and its chemical structure is the network cross-linked type, structural formula is as follows:
In the formula: m, n are the integer greater than 1, k=4~12.
Another object of the present invention provides a kind of preparation method of above-mentioned Biodegradable polyamideimide, may further comprise the steps:
1, citrate and 1: 0.2 in molar ratio~1: 5 mixed of aliphatie diamine is even, with the ratio of citrate gross weight 1~10wt% add catalyzer and with the reactant mixing, vacuum decompression carries out the condensation polymerization reaction and formed prepolymer in 1~6 hour under 50~100 ℃ temperature;
2, above-mentioned prepolymer is continued reaction 10~24 hours down at 50~160 ℃, obtain described Biodegradable polyamideimide.
Above-mentioned synthetic method also can be reduced to single stage method and carry out: after citrate and aliphatie diamine and catalyzer are mixed according to aforementioned proportion, under the vacuum under 50~120 ℃ temperature successive reaction aggregated into Biodegradable polyamideimide in 2~12 hours; Also can be under normal pressure under 25 ℃~60 ℃ temperature, successive reaction obtained Biodegradable polyamideimide in 48~72 hours in tetrahydrofuran (THF) or methyl-sulphoxide equal solvent.
Reaction process of the present invention is with citrate and aliphatie diamine reaction, generate the poly-citric amide prepolymer as shown in structural formula 1, further form again and contain the imido structural formula 2 of cyclic, the last structural formula 3 that between macromolecular chain, forms imido cross-bridge, thus the amide imide multipolymer become.Its reaction equation is as follows:
Structural formula 1, m, n are the integer greater than 1, k=4~12, j=1~10
Structural formula 2, m, n are the integer greater than 1, k=4~12, j=1~10
Structural formula 3, m, n are the integer greater than 1, k=4~12
Citric acid alkyl ester shown in the structural formula 1,2 is with-OC
jH
2j+1Expression, can be suitable for dissimilar esters, for example methyl esters (j=1) or ethyl ester (j=2) or the like: the diamines shown in the structural formula 1,2,3 is with N-(CH
2)
k-N represents, can be suitable for dissimilar diamines, for example octamethylenediamine (k=8), decamethylene diamine (k=10), butanediamine (k=4), pentamethylene diamine (k=5), heptamethylene diamine (k=7), 1,2-cyclohexanediamine etc.
As the further setting of the present invention:
Described citrate is one or more of alkyl esters such as trimethyl citrate, triethyl citrate, tributyl citrate or acetylize tributyl citrate.
Certainly, above-mentioned preparation method can be a starting raw material with citric acid fully, and the esterification through under the easy acid catalysis is converted into methyl citrate, ETHYL CTTRATE or butyl citrate etc., produces poly-citric amide imide with above-mentioned method again.Select for use simultaneously to contain-COOH and-citric acid of OH, the existence of these groups, help enzyme and water in conjunction with attack, and citric acid is the organism that occurs in microorganism and the animals and plants metabolic process, be in the world with the organic acid of biochemical method turnout maximum, available carbohydrate or the agricultural byproducts that are rich in saccharic are raw material, through diastatic fermentation, separate and produce, conveniently are easy to get.
Described aliphatie diamine is hexanediamine, heptamethylene diamine, octamethylenediamine, decamethylene diamine, butanediamine, pentamethylene diamine, 1, and carbonatomss such as 2-cyclohexanediamine are greater than 4 aliphatie diamine H
2N (CH
2-)
kNH
2One or more of (k>4).Wherein, pentamethylene diamine and butanediamine can utilize Methionin and ornithine to be raw material, by means of lysine decarboxylase and ornithine decarboxylase, make 1 fast under mild conditions, 5-pentamethylene diamine and 1,4-butanediamine.Use this two kinds of amine, corresponding being condensed into gathered the citric amide imide, avoided traditional required high energy consumption of process for preparing nylon, and most nylon and aromatic polyamide imide are degraded very slow in edatope.And diamine and the such natural organic acids condensation of citric acid of the present invention of adopting enzyme process to prepare become based on Biological resources synthetic " green " polymeric amide, and not only biological degradability is expected to take on a new look, and have reduced the dependence to oil.And, use hexanediamine then more cheap as raw material from the angle of production cost, more help large-scale industrial production.
The present invention can be under the environment of polar solvent, or without polar solvent but have under the condition of catalyzer synthetic.
Described catalyzer is weak base or weak acid, is preferably pyridine, triethylamine or phenol etc.The use of these catalyzer can make the ammonia of citrate separate-quickening of polycondensation process, needs to adopt highly active lemon acyl chlorides to make the shortcoming of raw material before having overcome.
The Biodegradable polyamideimide that the present invention makes is a cross-linked network type structure, its chemical structure is shown in structural formula 3, this be because, the all energy amidations of three ester groups of citrate, on ester group of citrate under the lesser temps reaction conditions and main chain two amine moieties-the NH-group can be easy to form the structure of imidization, obtain containing simultaneously on the main chain multipolymer of acid amides and imide structure.Owing to contain acid amides and imide group simultaneously in the product, and imide functionality appears on the cross-bridge, so this novel polyamidoimide material that is a class.Have following characteristics:
1, easily degraded: in the basic solution of pH=13, in 1.5 hours, can degrade fully under 70 ℃, become the solution that intrinsic viscosity [η] (25 ℃) has only 3.34ml/g.The poly-citric amide imide that makes can absorb the pure water that own wt is 45~49wt% in 48 hours, illustrative material itself contains hydroxyl, amide group and imide group makes hydrophilic ability grow.
2, the mould material of cross-linked network type or rubbery materials are for manufacturing practical engineering materials or the device goods have been created condition.The imido molecular weight of linear poly-citric amide that U.S. Pat 5026821 is described has only several thousand to 30,000, reprocessing change into various practical engineering materialss or the device goods difficult.
3, be insoluble to common organic solvent: in hot phenol, can resist certain hour, be different from general nylon; Also do not dissolve in ethanol, ether, phenylcarbinol, DMSO and hexanaphthene, also can resist certain hour in middle strong acid (pH=1 or the 2) solution of heat, its character is as shown in table 1:
Table 1. acid-and base-resisting and phenol test-results
Preparation method of the present invention has the following advantages:
1, synthesis technique is simple, and the reaction times is shorter, and crosslinking degree is more easy to control, and reaction yield can reach more than 90%.
2, the source of the raw material of Cai Yonging is abundant, and cost is low, and product price can be lower than other biodegradable polyhydroxyalkanoate and polyamino acid, is easy to apply, and comparatively remarkable economical and social benefit are arranged.
3, in macromolecular chain, introduce the contained hydroxyl of citric acid and the amido linkage and the imide bond of generation, make the wetting ability height of product.
4, by regulating the proportioning and the reaction times of starting raw material, can in very large range control the structure and the performance of product.
5, the shape of end product is controlled easily, and degraded both can be used as biodegradable elastomerics (vulcanite or leather) fully, also can be used as biodegradable duroplasts.
Description of drawings
Fig. 1 is the poly-imido infrared spectrogram of citric amide;
Fig. 2 is the poly-imido x-ray diffraction pattern of citric amide.
Specific embodiments
Embodiment 1
With tributyl citrate 10.0ml, 1,6-hexanediamine 5.0ml and triethylamine 1.0ml are mixed to join in the round-bottomed flask, receive on the Rotary Evaporators to be evacuated to-0.1MPa, and temperature is controlled at 50 ℃, react and get prepolymer after 6 hours, place while hot on the clean glass surface, it is sprawled evenly, vacuum-drying is 11.5 hours then, temperature is controlled at 160 ℃, obtains poly-citric amide imide.
Embodiment 2
With tributyl citrate 10.0ml, 1,6-hexanediamine 5.0ml and triethylamine 1.0ml are mixed to join in the round-bottomed flask, connect Rotary Evaporators, be evacuated to-0.04MPa about, room temperature reaction 2h.Then, continue revolving reaction 2h, obtain poly-citric amide imide 120 ℃ of heating.
Embodiment 3
With tributyl citrate 10.0ml, 1,6-hexanediamine 5.0ml and triethylamine 1.0ml are mixed to join in the round-bottomed flask, connect Rotary Evaporators, are evacuated to-0.04MPa, continue revolving reaction 12h 50 ℃ of heating, obtain poly-citric amide imide.
Embodiment 4
With tributyl citrate 10.0ml, 1,6-hexanediamine 5.0ml and triethylamine 1.0ml mix, and the room temperature normal pressure is in tetrahydrofuran solvent, and stirring reaction 48h obtains poly-citric amide imide.
Embodiment 5
With trimethyl citrate 10.0ml, 1,4-butanediamine 10.0ml and triethylamine 1.0ml are mixed to join in the round-bottomed flask, receive on the Rotary Evaporators to be evacuated to-0.1MPa, and temperature is controlled at 100 ℃, react and get prepolymer after 1 hour, place while hot on the clean glass surface, it is sprawled evenly, vacuum-drying is 24 hours then, temperature is controlled at 50 ℃, obtains poly-citric amide imide.
Embodiment 6
With trimethyl citrate 10.0ml, 1,4-butanediamine 10.0ml and triethylamine 1.0ml are mixed to join in the round-bottomed flask, receive on the Rotary Evaporators to be evacuated to-0.1MPa, and temperature is controlled at 75 ℃, react and get prepolymer after 5.5 hours, place while hot on the clean glass surface, it is sprawled evenly, vacuum-drying is 10 hours then, temperature is controlled at 160 ℃, obtains poly-citric amide imide.
Embodiment 7
With trimethyl citrate 10.0ml, 1,4-butanediamine 5.0ml and triethylamine 1.0ml are mixed to join in the round-bottomed flask, receive on the Rotary Evaporators to be evacuated to-0.1MPa, and temperature is controlled at 50 ℃, react and get prepolymer after 6 hours, place while hot on the clean glass surface, it is sprawled evenly, vacuum-drying is 12 hours then, temperature is controlled at 120 ℃, obtains poly-citric amide imide.
In the foregoing description: tributyl citrate 1mL=2.888mmol, hexanediamine 1mL=7.600mmol, butanediamine 1mL=9.98mmol, triethylamine 1mL=6.92mmol.The examination and test of products
With the product of the present invention preparation carry out infrared spectra and X-ray diffraction detect Fig. 1, shown in Figure 2:
Fig. 1 is the poly-imido infrared spectrogram of citric amide; Fig. 1 shows that the characteristic peak of amide functional group appears at 1635cm
-1And 1533cm
-1Deng the position, and imido characteristic peak appears at 1774cm
-1And 1704cm
-1Deng the position.
Fig. 2 is the poly-imido x-ray diffraction pattern of citric amide.Fig. 2 shows that the material that makes like this is unbodied solid basically, and crystallinity is very low, and these are different fully with general nylon.
The raw materials used marketable material that is among the above embodiment.The invention is not restricted to the foregoing description, content of the present invention is described all can be implemented, and has described good result.
Claims (10)
2, the preparation method of the described Biodegradable polyamideimide of a kind of claim 1 may further comprise the steps:
1., citrate and 1: 0.2 in molar ratio~1: 5 mixed of aliphatie diamine is even, with the ratio of citrate gross weight 1~10wt% add catalyzer and with the reactant mixing, vacuum decompression carries out the condensation polymerization reaction and formed prepolymer in 1~6 hour under 50~100 ℃ temperature;
2., above-mentioned prepolymer is continued down reaction 10~24 hours at 50~160 ℃, obtain described Biodegradable polyamideimide.
3, the preparation method of the described Biodegradable polyamideimide of a kind of claim 1, it is characterized in that: citrate and 1: 0.2 in molar ratio~1: 5 mixed of aliphatie diamine is even, with the ratio of citrate gross weight 1~10wt% add catalyzer and with the reactant mixing, under the vacuum under 50~120 ℃ temperature successive reaction aggregated into Biodegradable polyamideimide in 2~12 hours.
4, the preparation method of the described Biodegradable polyamideimide of a kind of claim 1, it is characterized in that: citrate and 1: 0.2 in molar ratio~1: 5 mixed of aliphatie diamine is even, with the ratio of citrate gross weight 1~10wt% add catalyzer and with the reactant mixing, in tetrahydrofuran (THF) or methyl-sulphoxide equal solvent, successive reaction obtained Biodegradable polyamideimide in 48~72 hours under 25 ℃~60 ℃ temperature under the normal pressure.
5, as the preparation method of Biodegradable polyamideimide as described in the claim 2~4, it is characterized in that: described citrate is one or more of alkyl esters such as trimethyl citrate, triethyl citrate, tributyl citrate or acetylize tributyl citrate.
6, as the preparation method of Biodegradable polyamideimide as described in the claim 5, it is characterized in that: described citrate is to be starting raw material with the citric acid, and the esterification through under the acid catalysis is converted into citrate.
7, as the preparation method of Biodegradable polyamideimide as described in the claim 2~4, it is characterized in that: described aliphatie diamine is hexanediamine, octamethylenediamine, decamethylene diamine, butanediamine, pentamethylene diamine, heptamethylene diamine, 1, and carbonatomss such as 2-cyclohexanediamine are greater than 4 aliphatie diamine
One or more of (k>4).
8, as the preparation method of Biodegradable polyamideimide as described in the claim 7, it is characterized in that: described aliphatie diamine is one or more of pentamethylene diamine, butanediamine, hexanediamine.
9, as the preparation method of Biodegradable polyamideimide as described in the claim 2~4, it is characterized in that: described catalyzer is weak base or weak acid.
10, as the preparation method of Biodegradable polyamideimide as described in the claim 9, it is characterized in that: described catalyzer is pyridine, triethylamine or phenol.
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102875803A (en) * | 2012-09-29 | 2013-01-16 | 绍兴文理学院 | Water-soluble polyamide, and preparation method and application thereof |
WO2017045987A1 (en) * | 2015-09-16 | 2017-03-23 | Basf Se | Novel biobased amines |
WO2019233795A1 (en) | 2018-06-06 | 2019-12-12 | Basf Se | Alkoxylated polyamidoamines as dispersant agents |
CN115651599A (en) * | 2022-01-24 | 2023-01-31 | 四川大学 | Polyamide hot melt adhesive and preparation method and application thereof |
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CN1229421C (en) * | 2003-04-04 | 2005-11-30 | 中国科学院化学研究所 | Soluble fluorine-containing polyamidoimide resin, its preparation method and application |
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Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102875803A (en) * | 2012-09-29 | 2013-01-16 | 绍兴文理学院 | Water-soluble polyamide, and preparation method and application thereof |
WO2017045987A1 (en) * | 2015-09-16 | 2017-03-23 | Basf Se | Novel biobased amines |
WO2019233795A1 (en) | 2018-06-06 | 2019-12-12 | Basf Se | Alkoxylated polyamidoamines as dispersant agents |
US11920000B2 (en) | 2018-06-06 | 2024-03-05 | Basf Se | Alkoxylated polyamidoamines as dispersant agents |
CN115651599A (en) * | 2022-01-24 | 2023-01-31 | 四川大学 | Polyamide hot melt adhesive and preparation method and application thereof |
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