CN102485766A - Aliphatic / aromatic copolyester and preparation method thereof - Google Patents
Aliphatic / aromatic copolyester and preparation method thereof Download PDFInfo
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- CN102485766A CN102485766A CN2010105712714A CN201010571271A CN102485766A CN 102485766 A CN102485766 A CN 102485766A CN 2010105712714 A CN2010105712714 A CN 2010105712714A CN 201010571271 A CN201010571271 A CN 201010571271A CN 102485766 A CN102485766 A CN 102485766A
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Abstract
The invention belongs to the field of material preparation and discloses a novel aliphatic / aromatic copolyester and a preparation method thereof. The aliphatic / aromatic copolyester of the invention has a molecular weight larger than 30000, an ultimate strength larger than 10 MPa and smaller than 50 MPa, an elongation at break larger than 5% and smaller than 3000%, Tg higher than -70 DEG C and lower than 40 DEG C, Tm higher than 50 DEG C and lower than 270 DEG C and a rate of biodegradation higher than 30%. The preparation method of the aliphatic / aromatic copolyester comprises steps of: adding cyclic aliphatic polyester and cyclic aromatic polyester into a reaction kettle; dissolving a catalyst in an organic solvent and adding into the reaction kettle; vacuumizing, filling nitrogen and removing oxygen in the reaction kettle; heating to evaporate the organic solvent; melting remain reaction mixture into a homogeneous system; controlling a reaction temperature at 170-260 DEG C; stirring and reacting for 1-24 h in a nitrogen environment; cooling to obtain the required aliphatic / aromatic copolyester. The aliphatic / aromatic copolyester of the invention has advantages of high molecular weight, excellent mechanical property and biodegradability, etc.
Description
Technical field
The invention belongs to field of material preparation, be specifically related to aliphatic/aromatic copolyesters of a kind of novelty and preparation method thereof, the gained copolyesters has the mechanical property and the biodegradability of higher molecular weight, excellence, is applicable to multiple field.
Background technology
In numerous macromolecular materials, polyester material is that consumption is big, one type of applied range, can be divided into two kinds of aromatic polyester and aliphatic polyesters simply by the chemical structure characteristics.Wherein, aromatic polyester has good resistance toheat and processing characteristics, and headed by polyethylene terephthalate, at present the production capacity in the whole world is with average annual about 9% speed expansion, breaks through 60Mt in 2009.(2009-2012 China polyethylene terephthalate market survey with investment consultation RR) but this type of material degradation property is poor, discarded back is difficult to degrade in physical environment, so can bring burden to environment.In order to solve the environmental problem that it brings, chemists are just making great efforts to give this family macromolecule material environment degradation capability.
The environment degradable ability is meant in the specified microorganisms effect, or under human body, animal internal milieu, macromolecular physics, chemical property decline take place form CO
2, H
2O, CH
4And ability (Yin Jinghua, the Mo Zhishen of some other small molecules quality compounds; Modern polymer is of science, and 2001, P382).The environment degradable material of research mainly refers to Biodegradable polyester at present, and Biodegradable polyester is meant a kind polyester that under nature microorganism such as bacterium, mould and algae effect, can resolve into micromolecular compound.Aliphatic polyester has favorable biological degradability; It is one type of Biodegradable polyester preferably; Yet relatively poor thermal property and processing characteristics are difficult to satisfy in the practical application the many-sided requirement of material property, have restricted its application, need carry out functional modification to it.
Therefore, preparation had both had the biodegradability of aliphatic polyester, and the polyester product that has the aromatic polyester processing characteristics again just becomes the research emphasis of current polymeric material field.Simple blend is to be difficult to meet the requirements of; Though can improve the resistance toheat and the processing characteristics of aliphatic polyester to a certain extent; But in biodegradation process; After degradable aliphatic polyester degraded was accomplished, remaining aromatic polyester still was present in the physical environment with long molecular chain, causes serious environmental problem.By contrast, the aromatic polyester unit is introduced in the molecular chain of aliphatic polyester, can be obtained that mechanical property is good, thermostability is high, good biocompatibility and the good aliphatic/aromatic copolyester material of biodegradability through chemosynthesis.(R.J.Muller，I.Kleeberg，W.D.Deckwer.Biodegradation?of?Polyesters?Containing?Aromatic?Constituents.J.Biotechnol.，2006，86，87-95.)
Up to the present; A lot of aliphatic/aromatic copolyesters have been realized industrialization, for example poly-succinic acid-butanediol/polybutylene terephthalate copolyesters, gather hexanodioic acid butyleneglycol-Succinic Acid butyleneglycol/polybutylene terephthalate copolyesters, poly-succinic acid-butanediol/poly terephthalic acid terepthaloyl moietie copolyesters, gather adipate glycol/poly terephthalic acid terepthaloyl moietie copolyesters etc.This type copolyesters is normally realized its degradation function through enzyme or mikrobe under various envrionment conditionss.Ecoflex
, Biomax
and Eastar-Bio
polymkeric substance are exactly the copolyesters product that comprises aliphatic polyester and terephthalic acid units that BASF, Du Pont and Eastman Chemical produce respectively, and they have possessed use properties and degradation property preferably simultaneously.(Xu Chihuan, the exploitation of copolyesters and application, New Chemical Materials, 2001,29,24-25.) but these aliphatic/aromatic copolyesters all are to adopt divalent alcohol and the method for diprotic acid (or their corresponding dimethyl esters) through traditional melt phase polycondensation to prepare.Because the equilibrium constant of polyester polycondensation reaction is less; Vacuumizing that reaction process need not stopped extracted small molecule by-product out from the reactive polymeric thing; Promote reaction to carry out to positive dirction; Very high at polymerization late phase reaction system viscosity, small molecules is not easy to remove, thereby final polymericular weight is not very high.And the reaction process temperature is higher, and energy consumption is bigger, and the performance that thermolysis influences the finished product takes place easily.
Another method of preparation aliphatic/aromatic copolyesters is ring-opening polymerization, and ring-opening polymerization is meant the process of macrocyclic oligomer thing ring-opening polymerization under the effect of initiator or catalyzer formation linear molecule polymkeric substance.Compare with melt phase polycondensation, ring-opening polymerization method reaction temperature and, easily control, energy consumption are little, and this method can obtain the bigger polymkeric substance of molecular weight.
Summary of the invention
The purpose of this invention is to provide a kind of aliphatic/aromatic copolyesters with excellent mechanical processing characteristics and biodegradability.
Another object of the present invention provides a kind of preparation method of above-mentioned aliphatic/aromatic copolyesters.
Technical scheme of the present invention is following:
The invention provides a kind of aliphatic/aromatic copolyesters, the molecular weight of this copolyesters＞30000,10MPa＜US＜50MPa, 5%＜elongation at break＜3000% ,-70 ℃＜Tg＜40 ℃, 50 ℃＜Tm＜270 ℃, biological degradation rate＞30%.
The present invention also provides a kind of preparation method of above-mentioned aliphatic/aromatic copolyesters, and this method may further comprise the steps:
In reaction kettle, add annular aliphatic polyester and ring-type aromatic polyester, catalyzer is dissolved in the organic solvent; Join in the reaction kettle, vacuumize, inflated with nitrogen removes the oxygen in the reaction kettle, heating steams organic solvent; After the residue reaction mixture is fused into homogeneous system fully; Control reaction temperature is 170～260 ℃, stirring reaction 1～24h under nitrogen environment, and cooling obtains required aliphatic/aromatic copolyesters;
Wherein, the polyester unit mol ratio of annular aliphatic polyester and ring-type aromatic polyester is 10: 90～90: 10, preferred 20: 80～80: 20; Catalyst consumption is 0.01～1wt% of the total consumption of cyclic polyester (annular aliphatic polyester and ring-type aromatic polyester), preferred 0.05～1wt%; The concentration that catalyzer is dissolved in organic solvent is 0.001～0.2g/mL, preferred 0.005～0.1g/mL.
Described annular aliphatic polyester is selected from one or several the mixture in ring-type oxalic acid glycol ester, ring-type oxalic acid butanediol ester, ring-type EGS ethylene glycol succinate, ring-type succinic acid-butanediol ester, ring-type ethylene glycol adipate(EGA) or the ring-type tetramethylene adipate.
Described ring-type aromatic polyester is selected from the mixture of a kind of among ring-type ethylene glycol terephthalate or the ring-type mutual-phenenyl two acid bromide two alcohol ester or two kinds.
Described catalyzer is selected from one or more the mixture in stannous octoate, dibutyltin oxide, aluminum isopropylate or the triethyl aluminum.
Described organic solvent is selected from methylene dichloride, trichloromethane, tetracol phenixin or 1, the mixture of one or more in the 2-ethylene dichloride.
The present invention compares with prior art, has following advantage and beneficial effect:
1, the inventive method reaction conditions is gentle, and controllable process need not the high pressure high vacuum, helps avoiding industrial accident, safety in production.
2, gained copolyesters of the present invention has higher molecular weight and excellent mechanical property, biodegradability, can design, produce the copolyesters of specified property according to actual needs, is applicable to multiple field, like products such as preparation film, spinning, sheet material, printing ink.
3, aliphatic/aromatic copolyesters of the present invention; Can straight forming, need not following process, the disposable injection mould of mixture; Ring-opening reaction promptly can the demoulding obtain required goods after finishing; So greatly having improved production efficiency, be well suited for preparing the complicated goods of moulding, is a kind of very potential method.
4, aliphatic/aromatic copolyesters of the present invention behind the product abandonment, can be degraded in physical environment automatically, does not stay any harmful side product, has realized and the getting along amiably and peacefully of nature.
Embodiment
Below in conjunction with embodiment the present invention is further described.
Among the embodiment that provides below, adopt following detection method:
Adopt differential scanning calorimeter Perkin Elmer DSC7, under following type of heating, measure second-order transition temperature T
gWith melt temperature T
m:
Scanning with 50 ℃/min, is warming up to 270 ℃ from-100 ℃ for the first time;
Scanning with 10 ℃/min, is cooled to-100 ℃ from 270 ℃ for the second time;
Scanning with 20 ℃/min, is warming up to 270 ℃ from-100 ℃ for the third time.
Weight-average molecular weight M
wIn Waters 600E series GPC system, measure, wherein chloroform is used for working curve as elutriant and polystyrene standard sample.
Biodegradability:
Test with controlled composting processing biodegrade according to standard ISO 14855amendment 1.Sample is cut into the print that area is 2cm * 2cm through hot pressing film forming (10～20 μ m), imbeds in the petridish that composting soil is housed, and puts into the incubator of fixed temperature and humidity together, keeps humidity about 50%, temperature (58 ± 2) ℃.Its surface topography is observed and write down to the weightlessness of period sampling measuring sample.
Embodiment 1
In the 10L reaction kettle, add 1.16kg ring-type oxalic acid glycol ester, 1.92kg ring-type ethylene glycol terephthalate, the 7.5g dibutyltin oxide is dissolved in the 500mL chloroform adds in the reaction kettle; Vacuumize, inflated with nitrogen removes the oxygen in the reaction kettle; Heating is steamed chloroform, and after the residue reaction mixture was fused into homogeneous system fully, control reaction temperature was 240 ℃; Stirring reaction 8h under nitrogen environment, stopped reaction.Reaction mixture is taken out from still, and cooling forming in water promptly gets the oxalic acid terepthaloyl moietie copolyesters of poly terephthalic acid terepthaloyl moietie-(50%mol).
The gained copolyesters is through detecting, and its weight-average molecular weight is 40200, and elongation at break is 6%, and US is 37MPa, T
g=-21 ℃, T
m=170 ℃, biological degradation rate is 87%.
Embodiment 2
In the 10L reaction kettle, add 0.72kg ring-type EGS ethylene glycol succinate, 3.3kg ring-type mutual-phenenyl two acid bromide two alcohol ester; The 10g stannous octoate is dissolved in the 600mL tetracol phenixin adds in the reaction kettle, vacuumize, inflated with nitrogen removes the oxygen in the reaction kettle, heating is steamed tetracol phenixin; After the residue reaction mixture is fused into homogeneous system fully; Control reaction temperature is 260 ℃, stirring reaction 6h under nitrogen environment, stopped reaction.Reaction mixture is taken out from still, and cooling forming in water promptly gets the Succinic Acid terepthaloyl moietie copolyesters of polybutylene terephthalate-(25%mol).
The gained copolyesters is through detecting, and its weight-average molecular weight is 53100, and elongation at break is 352%, and US is 42MPa, T
g=5 ℃, T
m=183 ℃, biological degradation rate is 63%.
Embodiment 3
In the 10L reaction kettle, add 2kg ring-type tetramethylene adipate, 0.96kg ring-type ethylene glycol terephthalate, 1.1kg ring-type mutual-phenenyl two acid bromide two alcohol ester, the 9g aluminum isopropylate is dissolved in 400mL 1, the 2-ethylene dichloride adds in the reaction kettle; Vacuumize, inflated with nitrogen removes the oxygen in the reaction kettle, heating makes 1, the 2-ethylene dichloride is steamed; After the residue reaction mixture is fused into homogeneous system fully; Control reaction temperature is 250 ℃, stirring reaction 10h under nitrogen environment, stopped reaction.Reaction mixture is taken out from still, and cooling forming in water promptly gets the hexanodioic acid butyleneglycol copolyesters of the terephthalic acid terepthaloyl moietie of polybutylene terephthalate-(25%mol)-(50%mol).
The gained copolyesters is through detecting, and its weight-average molecular weight is 60700, and elongation at break is 1546%, and US is 23MPa, T
g=-24 ℃, T
m=147 ℃, biological degradation rate is 91%.
Embodiment 4
In the 10L reaction kettle, add 1.08kg ring-type oxalic acid butanediol ester, 1.29kg ring-type succinic acid-butanediol ester, 0.96kg ring-type ethylene glycol terephthalate; 4g aluminum isopropylate, 3g triethyl aluminum are dissolved in the 700mL methylene dichloride add in the reaction kettle, vacuumize, inflated with nitrogen removes the oxygen in the reaction kettle, heating is steamed methylene dichloride; After the residue reaction mixture is fused into homogeneous system fully; Control reaction temperature is 230 ℃, stirring reaction 12h under nitrogen environment, stopped reaction.Reaction mixture is taken out from still, and cooling forming in water promptly gets the Succinic Acid butyleneglycol copolyesters of the oxalic acid butyleneglycol of poly terephthalic acid terepthaloyl moietie-(37.5%mol)-(37.5%mol).
The gained copolyesters is through detecting, and its weight-average molecular weight is 65300, and elongation at break is 1387%, and US is 28MPa, T
g=-35 ℃, T
m=106 ℃, biological degradation rate is 98%.
Embodiment 5
In the 10L reaction kettle, add 2kg ring-type tetramethylene adipate, 2.2kg ring-type mutual-phenenyl two acid bromide two alcohol ester, the 6g dibutyltin oxide is dissolved in the 500mL methylene dichloride adds in the reaction kettle, vacuumize, inflated with nitrogen removes the oxygen in the reaction kettle; Heating makes that methylene dichloride is steamed; After the residue reaction mixture is fused into homogeneous system fully, reaction mixture is injected in the mould, the control die temperature is 250 ℃; Isothermal reaction 20h; Reduce to normal temperature, reaction product is taken out from mould, promptly get the hexanodioic acid butyleneglycol copolyester object of the polybutylene terephthalate of straight forming-(50%mol).
The gained copolyesters is through detecting, and its weight-average molecular weight is 68400, and elongation at break is 1642%, and US is 25MPa, T
g=-33 ℃, T
m=135 ℃, biological degradation rate is 93%.
Through implementation process and the detected result of each embodiment, can know by preparation method of the present invention and can utilize annular aliphatic polyester and ring-type aromatic polyester through ring-opening polymerization, prepare the aliphatic/aromatic copolyesters of various components, various performances easily.Reaction process is gentle, and temperature is lower, is convenient to control, and energy consumption is little.The copolyesters molecular weight that obtains is higher, has mechanical property and biodegradability preferably.In addition, various molten monomers are mixed the disposable injection mould in back, can straight forming, need not following process, ring-opening reaction promptly can the demoulding obtain required goods after finishing, and has greatly improved production efficiency.
Above-mentioned description to embodiment is can understand and use the present invention for the ease of the those of ordinary skill of this technical field.The personnel of skilled obviously can easily make various modifications to these embodiment, and needn't pass through performing creative labour being applied in the General Principle of this explanation among other embodiment.Therefore, the invention is not restricted to the embodiment here, those skilled in the art are according to announcement of the present invention, and not breaking away from the improvement that category of the present invention makes and revise all should be within protection scope of the present invention.
Claims (7)
1. an aliphatic/aromatic copolyesters is characterized in that: the molecular weight of this aliphatic/aromatic copolyesters＞30000,10MPa＜US＜50MPa; 5%＜elongation at break＜3000%;-70 ℃＜Tg＜40 ℃, 50 ℃＜Tm＜270 ℃, biological degradation rate＞30%.
2. the preparation method of the described aliphatic/aromatic copolyesters of claim 1, it is characterized in that: this method may further comprise the steps,
In reaction kettle, add annular aliphatic polyester and ring-type aromatic polyester, catalyzer is dissolved in the organic solvent; Join in the reaction kettle, vacuumize, inflated with nitrogen removes the oxygen in the reaction kettle, heating steams organic solvent; After the residue reaction mixture is fused into homogeneous system fully; Control reaction temperature is 170～260 ℃, stirring reaction 1～24h under nitrogen environment, and cooling obtains required aliphatic/aromatic copolyesters.
3. the preparation method of aliphatic/aromatic copolyesters according to claim 2 is characterized in that: the polyester unit mol ratio of described annular aliphatic polyester and ring-type aromatic polyester is 10: 90～90: 10; Catalyst consumption is 0.01～1wt% of the total consumption of cyclic polyester; The concentration that catalyzer is dissolved in organic solvent is 0.001～02g/mL.
4. the preparation method of aliphatic/aromatic copolyesters according to claim 2 is characterized in that: described annular aliphatic polyester is selected from one or several the mixture in ring-type oxalic acid glycol ester, ring-type oxalic acid butanediol ester, ring-type EGS ethylene glycol succinate, ring-type succinic acid-butanediol ester, ring-type ethylene glycol adipate(EGA) or the ring-type tetramethylene adipate.
5. the preparation method of aliphatic/aromatic copolyesters according to claim 2 is characterized in that: described ring-type aromatic polyester is selected from the mixture of a kind of among ring-type ethylene glycol terephthalate or the ring-type mutual-phenenyl two acid bromide two alcohol ester or two kinds.
6. the preparation method of aliphatic/aromatic copolyesters according to claim 2 is characterized in that: described catalyzer is selected from one or more the mixture in stannous octoate, dibutyltin oxide, aluminum isopropylate or the triethyl aluminum.
7. the preparation method of aliphatic/aromatic copolyesters according to claim 2 is characterized in that: described organic solvent is selected from methylene dichloride, trichloromethane, tetracol phenixin or 1, the mixture of one or more in the 2-ethylene dichloride.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102746741A (en) * | 2012-07-24 | 2012-10-24 | 江苏科技大学 | Conductive ink for PET thin film of keyboard |
| WO2018072747A1 (en) * | 2016-10-21 | 2018-04-26 | 中国石油化工股份有限公司 | Polyester composition and preparation method therefor |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102336896A (en) * | 2010-07-27 | 2012-02-01 | 上海杰事杰新材料(集团)股份有限公司 | Preparation method of lightly-crosslinked aliphatic-aromatic copolyester |
| CN102477149A (en) * | 2010-11-29 | 2012-05-30 | 上海杰事杰新材料(集团)股份有限公司 | Preparation method of biodegradable aliphatic-aromatic copolyester |
-
2010
- 2010-12-02 CN CN2010105712714A patent/CN102485766A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102336896A (en) * | 2010-07-27 | 2012-02-01 | 上海杰事杰新材料(集团)股份有限公司 | Preparation method of lightly-crosslinked aliphatic-aromatic copolyester |
| CN102477149A (en) * | 2010-11-29 | 2012-05-30 | 上海杰事杰新材料(集团)股份有限公司 | Preparation method of biodegradable aliphatic-aromatic copolyester |
Non-Patent Citations (1)
| Title |
|---|
| PATHAVUTH MONVISADE ET AL.: "Synthesis of poly(ethylene adipate) and poly(ethylene adipateco-terephthalate) via ring-opening polymerization", 《EUROPEAN POLYMER JOURNAL》, vol. 43, 23 May 2007 (2007-05-23) * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102746741A (en) * | 2012-07-24 | 2012-10-24 | 江苏科技大学 | Conductive ink for PET thin film of keyboard |
| WO2018072747A1 (en) * | 2016-10-21 | 2018-04-26 | 中国石油化工股份有限公司 | Polyester composition and preparation method therefor |
| US11053385B2 (en) | 2016-10-21 | 2021-07-06 | China Petroleum & Chemical Corporation | Polyester composition and preparation method therefor |
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Application publication date: 20120606 |