CN101597374A - The preparation method of long chain branch polylactic acid - Google Patents
The preparation method of long chain branch polylactic acid Download PDFInfo
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- CN101597374A CN101597374A CNA2009100549037A CN200910054903A CN101597374A CN 101597374 A CN101597374 A CN 101597374A CN A2009100549037 A CNA2009100549037 A CN A2009100549037A CN 200910054903 A CN200910054903 A CN 200910054903A CN 101597374 A CN101597374 A CN 101597374A
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Abstract
A kind of preparation method of long chain branch polylactic acid of chemical field, under comprising the steps: at first 190～210 ℃ with the fusion of 100 parts of line style poly(lactic acid), add 0.5～1 part of oxidation inhibitor then, add 0.03～0.06 part of polyfunctional monomer afterwards again, blend 10～30min prepares long chain branch polylactic acid; Described umber is parts by weight; Wherein, described polyfunctional monomer is one or more the mixing in the epoxy monomer of functionality 〉=3.The molecular weight of the product that the present invention obtains, modulus and melt strength are improved, and can be used to moulding processes such as foaming, blown film.
Description
Technical field
The present invention relates to a kind of preparation method of chemical technology field, specifically is a kind of preparation method of long chain branch polylactic acid.
Background technology
Along with the aggravation of oil crisis and the urgency of environmental improvement problem, poly(lactic acid) is as the substitute of conventional plastic, and the outstanding advantage of material itself is arranged: it derives from renewable resources, can alleviate the dependency of the source of polymer materials to refining of petroleum; Poly(lactic acid) can be degraded under certain condition fully, has avoided the generation of " white pollution " from the source, from truly having realized the natural circulation of material; In addition, the machinery of poly(lactic acid) and physicals are relatively good comparatively speaking in polyester, glossiness and transparency height are also arranged, to advantages such as human body toxicological harmlesss.These characteristics make poly-lactic acid material that wide application prospect be arranged, and are expected to be widely used in food product pack, agriculture consumptive material, the household electrical appliances and the consumer's goods, fields such as fabric and health care.But the manufacturing finished product that does not also extensively occur at present why this material on the market, be because some drawbacks limit of material itself practical application, comprise that degree of crystallinity is low, crystallization rate is slow, poor toughness etc., wherein one of most important limiting factor is that the melt strength of material is very low, and this has caused machine-shaping process difficulties such as blown film, foaming, hollow blow molding.In addition, the linear polymerization product of directly preparing is easily degraded in the melt process, and the molecular weight ratio of the finished product is lower, has caused use properties poor.
The method of above two the critical limitation factors of common solution is: (1) utilizes the rac-Lactide ring-opening polymerization to obtain high molecular weight polylactic acid, but this class methods efficient is lower, synthetic route is tediously long, and cost is very high, is unfavorable for the wide popularization and application of poly(lactic acid) biodegradable material; (2) by the direct condensation method synthesizing polylactic acid of lactic acid, this method cost is relatively low, but the method for melt polymerization or solution polymerization is unfavorable for obtaining the high-molecular weight product, does not tackle the problem at its root; (3) earlier make molecular weight at 1～20,000 prepolymer that has a carboxyl by polyreaction, carry out chain extension with the reaction method for processing afterwards, this method can obtain the high-molecular weight product, but on the one hand because the existence of prepolymer carboxyl and will utilize the functional group reactions of carboxyl to carry out chain extension subsequently, polymkeric substance in the course of processing and the stability that forms behind the product be difficult to guarantee; On the other hand, the main used chainextender toxicity based on isocyanic ester of this method is very big, is unfavorable for that the finished product are applied to industries such as food product pack; Moreover even if what obtain is higher molecular weight line style poly(lactic acid), the problem that melt strength is low is not still well improved, and blown film, the foaming course of processing still can not fine must the realizations; (4) the line style poly(lactic acid) with higher molecular weight is carried out branching in the melt-processed process, can adopt and add the method that superoxide causes free radical reaction, obtains the higher product of molecular weight.This method is more simple and easy to do, but because the randomness of free radical reaction, the effect of the DeR of following in the course of processing in addition is difficult to the final structure and the molecular weight of control product, thereby is difficult to guarantee the performance of product.Therefore, how to adopt the line style poly(lactic acid) (expecting in 10～200,000 commerce) of the good stability that has had molecular weight such as molecular weight, by the reactive blending method for melt processing, convenient and swift obtain cost low, have high fondant-strength, be easy to the poly-lactic acid material of forming process, crucial Practical significance and industrial value are arranged.
Find through literature search, do not see the report relevant as yet with technical scheme of the present invention to prior art.
Summary of the invention
The objective of the invention is to overcome the deficiencies in the prior art, a kind of preparation method of long chain branch polylactic acid is provided.It is low to the objective of the invention is to solve the poly-lactic acid material melt strength, cause foaming, the problem of machine-shaping process difficulty such as blown film, the molecular weight of the long chain branch polylactic acid that the present invention obtains, modulus and melt strength are improved, and can be used to moulding processes such as foaming, blown film.
The present invention is achieved by the following technical solutions, the present invention includes following steps:
With the fusion of 100 parts of line style poly(lactic acid), add 0.5～1 part of oxidation inhibitor then under 190～210 ℃, add 0.03～0.06 part of polyfunctional monomer afterwards again, blend 10～30min prepares long chain branch polylactic acid; Described umber is parts by weight;
Wherein, described polyfunctional monomer is one or more the mixing in the epoxy monomer of functionality 〉=3.
Described fusion is to carry out in Banbury mixer or forcing machine.
Described Banbury mixer rotating speed is 40～100rpm.
Described oxidation inhibitor is hindered phenol antioxygen or phosphite ester kind antioxidant.
Described oxidation inhibitor is 1,3,5-trimethylammonium-2,4,6-(3,5-di-t-butyl-4-hydroxybenzene methyl) benzene, four [methyl-(3, the 5-di-tert-butyl-hydroxy phenyl) propionic acid] pentaerythritol ester, 2,6 di tert butyl 4 methyl phenol, 4,4 thiobiss (the 6-tertiary butyl-3-methylphenol), 3, a kind of in the two β of 5-di-t-butyl-4 hydroxy phenyl propionic acid octadecanol ester, triglycol-(3-tertiary butyl-4-hydroxy-5-aminomethyl phenyl) propionic ester or three (2, the 4-di-t-butyl) phenyl-phosphite.
Described polyfunctional monomer is triglycidyl isocyanurate, four Racemic glycidol diaminodiphenylmethane, triglycidyl group p-aminophenol, [1,1,2,2-four (p-hydroxybenzene) ethane four glycidyl ethers], 1,1,2, the mixing of one or more in 2-four p-hydroxybenzene ethane four glycidyl ethers, Resorcinol formal four glycidyl ethers, Phloroglucinol monomethyl ether triglycidyl ether, two Resorcinol formal four glycidyl ethers, p-aminophenol triglycidyl group Resins, epoxy or four phenolic group ethane, four glycidyl ethers.
Compared with prior art, the present invention has following beneficial effect: by the functional group reactions that carries out with the line style poly(lactic acid) in the course of processing, obtained the long-chain branch product of metastable high molecular, high-modulus, high fondant-strength, low melt index, and can control to a certain extent the structure and the molecular weight of reaction product by regulating monomeric consumption and speed of reaction.The present invention is easy, efficient, cost is low, and reaction product can be used for machine-shaping processes such as foaming, blown film, hollow blow molding.
Description of drawings
Fig. 1 is the draft flowing deformation graphic representation that long chain branch polylactic acid material that embodiment 1 obtains is compared with pure line style poly(lactic acid);
Fig. 2 is the storage modulus G ' that compares with pure line style poly(lactic acid) of long chain branch polylactic acid material that embodiment 1 obtains and the flow curve figure of frequencies omega;
Fig. 3 is the optical microscope photograph that the long chain branch polylactic acid material that obtains of embodiment 1 and pure line style poly(lactic acid) carry out obtaining after the supercritical co foaming product under the same conditions.
Embodiment
Below embodiments of the invention are elaborated: present embodiment has provided detailed embodiment and process being to implement under the prerequisite with the technical solution of the present invention, but protection scope of the present invention is not limited to following embodiment.The experimental technique of unreceipted actual conditions in the following example is usually according to normal condition.
Used poly(lactic acid) is the commercial material of line style poly(lactic acid) in following examples, and melting index is 4.10g/10min.Umber is parts by weight described in the embodiment.
The preparation of long chain branch polylactic acid
100 parts of polylactic acid raw material are added under 190 ℃ in the Haake Banbury mixer to fusion fully, add 0.5 part 1,3,5-trimethylammonium-2,4,6-(3,5-di-t-butyl-4-hydroxybenzene methyl) benzene, to be mixed evenly after, add 0.04 part of triglycidyl isocyanurate immediately, reactive blending 20min, the Banbury mixer rotating speed is 60rpm, obtains a kind of long chain branch polylactic acid material.Described oxidation inhibitor can prevent poly(lactic acid) thermooxidative degradation in the course of processing.The reaction product material that obtains is as shown in table 1 according to the melting index result that the ASTMD1238 standard records.
Fig. 1 is the draft flowing deformation curve that long chain branch polylactic acid material that embodiment 1 obtains is compared with pure line style poly(lactic acid), the strain hardening phenomenon does not all appear in the line style poly(lactic acid) under different stretch speed as can be seen, and tangible strain hardening phenomenon has appearred through the reacted poly-lactic acid material of drawing money on credit of fusion, prove the existence of drawing money on credit, shown the remarkable rising of gained material melt strength.
Fig. 2 is the storage modulus G ' that compares with pure line style poly(lactic acid) of long chain branch polylactic acid material that embodiment 1 obtains and the flow curve figure of frequencies omega.Test condition is 180 ℃, 0.01～100rad/s, strain 5% (all samples is all in linear viscoelastic region under this strain).Can see at whole frequency fields, compare, through obvious must the increase of storage modulus G ' of drawing money on credit of fusion reaction material processed with pure line style poly(lactic acid).The reaction product that this phenomenon explanation embodiment 1 obtains has longer time of relaxation than line style poly(lactic acid), flowability is slowed down, illustrated that tangible long-chain branch generates, infer the long-chain branch topological framework that in this system based on star structure according to reaction mechanism and rheology characterizing method, also have tree structure to exist.
Fig. 3 is the optical microscope photograph that the long chain branch polylactic acid material that obtains of embodiment 1 and pure line style poly(lactic acid) carry out obtaining after the supercritical co foaming product under the same conditions.Can see that from the contrast picture because the line style polylactic acid melt intensity before the reaction is very low, obvious failure by rupture has taken place foaming back cell wall, so that abscess is linked to be huge cavity; And compact through the material abscess rule of drawing money on credit of fusion reaction, the material after the branching has higher melt strength, therefore can keep the original shape of abscess, as seen is very beneficial for foaming processing through the product after the drawing money on credit of fusion of the present invention.
Embodiment 2
The preparation of long chain branch polylactic acid
100 parts of polylactic acid raw material are added under 200 ℃ in the Haake Banbury mixer to fusion fully, add 0.5 part 1,3,5-trimethylammonium-2,4,6-(3,5-di-t-butyl-4-hydroxybenzene methyl) benzene, to be mixed evenly after, add 0.03 part of triglycidyl isocyanurate immediately, reactive blending 10min, the Banbury mixer rotating speed is 40rpm, obtains a kind of long chain branch polylactic acid material.Test result is as shown in table 1.
Embodiment 3
The preparation of long chain branch polylactic acid
100 parts of polylactic acid raw material are added under 210 ℃ in the Haake Banbury mixer to fusion fully, add 0.5 part 1,3,5-trimethylammonium-2,4,6-(3,5-di-t-butyl-4-hydroxybenzene methyl) benzene, to be mixed evenly after, add 0.06 part of triglycidyl isocyanurate immediately, reactive blending 30min, the Banbury mixer rotating speed is 80rpm, obtains a kind of long chain branch polylactic acid material.Test result is as shown in table 1.
Embodiment 4
The preparation of long chain branch polylactic acid-epoxies polyfunctional monomer mixture
100 parts of polylactic acid raw material are added under 200 ℃ in the Haake Banbury mixer to fusion fully, add 0.5 part 1,3,5-trimethylammonium-2,4,6-(3,5-di-t-butyl-4-hydroxybenzene methyl) benzene, to be mixed evenly after, add 0.04 part triglycidyl isocyanurate and 0.02 part four Racemic glycidol diaminodiphenylmethane, reactive blending 10min, the Banbury mixer rotating speed is 100rpm, obtains a kind of long chain branch polylactic acid material.Test result is as shown in table 1.
Embodiment 5
The preparation of long chain branch polylactic acid
100 parts of polylactic acid raw material are added under 190 ℃ in the Haake Banbury mixer to fusion fully, add 0.7 part of four [methyl-(3, the 5-di-tert-butyl-hydroxy phenyl) propionic acid] pentaerythritol ester, to be mixed evenly after, add 0.03 part of four Racemic glycidol diaminodiphenylmethane immediately, reactive blending 15min, the Banbury mixer rotating speed is 40rpm, obtains a kind of long chain branch polylactic acid material.Test result is as shown in table 1.
Embodiment 6
The preparation of long chain branch polylactic acid
100 parts of polylactic acid raw material are added under 200 ℃ in the Haake Banbury mixer to fusion fully, add 1 part 2, the 6-di-tert-butyl-4-methy phenol, to be mixed evenly after, add 0.04 part 1 immediately, 1,2,2-four p-hydroxybenzene ethane four glycidyl ethers, reactive blending 15min, the Banbury mixer rotating speed is 60rpm, obtains a kind of long chain branch polylactic acid material.Test result is as shown in table 1.
Embodiment 7
The preparation of long chain branch polylactic acid
100 parts of polylactic acid raw material are added under 200 ℃ in the Haake Banbury mixer to fusion fully, add 0.8 part 4,4 thiobiss (the 6-tertiary butyl-3-methylphenol), to be mixed evenly after, add 0.04 part of two Resorcinol formal four glycidyl ether immediately, reactive blending 15min, the Banbury mixer rotating speed is 110rpm, obtains a kind of long chain branch polylactic acid material.Test result is as shown in table 1.
Embodiment 8
The preparation of long chain branch polylactic acid
Reactant ratio is identical with embodiment 1, implements on forcing machine, and screw slenderness ratio is 44: 1, rotating speed 100rpm, totally 11 districts, the 1-4 district is provided with temperature and is respectively: 180 ℃ (feeding mouth), 240 ℃, 260 ℃, 270 ℃, 11 districts are 280 ℃ (heads), and all the other are 270 ℃.Test result is as shown in table 1.
The melting index test result as can be seen from table 1, compare with the line style polylactic acid raw material, the product melting index of embodiment 1-3 all obviously reduces, shown the remarkable rising of viscosity of material and modulus, the mobile reduction, low melt index helps machine-shaping processes such as foaming, blown film, hollow blow molding.Embodiment 4 products have recorded gelatin phenomenon, and gel fraction is about 10%, as seen uses functionality 〉=3 epoxy monomer mixtures better than the epoxy monomer effect of simple use functionality 〉=3.The drawing money on credit degree that estimation obtains is about 80% for embodiment 1,2,4, and embodiment 3,5 is about about 50%.
Table 1
Claims (6)
1, a kind of preparation method of long chain branch polylactic acid is characterized in that, comprises the steps:
At first, under 190～210 ℃ with the fusion of 100 parts of line style poly(lactic acid);
Then, add 0.5～1 part of oxidation inhibitor;
Afterwards, add 0.03～0.06 part of polyfunctional monomer again, blend 10～30min prepares long chain branch polylactic acid;
Wherein: described umber is parts by weight; Described polyfunctional monomer is one or more the mixing in the epoxy monomer of functionality 〉=3.
2, the preparation method of long chain branch polylactic acid according to claim 1 is characterized in that, described fusion is to carry out in Banbury mixer or forcing machine.
3, the preparation method of long chain branch polylactic acid according to claim 2 is characterized in that, the rotating speed of described Banbury mixer is 40～100rpm.
4, the preparation method of long chain branch polylactic acid according to claim 1 is characterized in that, described oxidation inhibitor is hindered phenol antioxygen or phosphite ester kind antioxidant.
5, preparation method according to claim 1 or 4 described long chain branch polylactic acids, it is characterized in that, described oxidation inhibitor is 1,3,5-trimethylammonium-2,4,6-(3,5-di-t-butyl-4-hydroxybenzene methyl) benzene, four [methyl-(3, the 5-di-tert-butyl-hydroxy phenyl) propionic acid] pentaerythritol ester, 2,6 di tert butyl 4 methyl phenol, 4,4 thiobiss (the 6-tertiary butyl-3-methylphenol), 3,5-di-t-butyl-4 hydroxy phenyl propionic acid octadecanol ester, the two β of triglycol-(3-tertiary butyl-4-hydroxy-5-aminomethyl phenyl) propionic ester, or a kind of in three (2, the 4-di-t-butyl) phenyl-phosphite.
6, the preparation method of long chain branch polylactic acid according to claim 1, it is characterized in that, described polyfunctional monomer is a triglycidyl isocyanurate, four Racemic glycidol diaminodiphenylmethane, the triglycidyl group p-aminophenol, [1,1,2,2-four (p-hydroxybenzene) ethane four glycidyl ethers], 1,1,2,2-four p-hydroxybenzene ethane four glycidyl ethers, Resorcinol formal four glycidyl ethers, the Phloroglucinol monomethyl ether triglycidyl ether, two Resorcinol formal four glycidyl ethers, p-aminophenol triglycidyl group Resins, epoxy, or one or more the mixing in four phenolic group ethane, four glycidyl ethers.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102453250A (en) * | 2010-10-25 | 2012-05-16 | 中国石油化工股份有限公司 | Method for preparing long chain branched polylactic resin by combining two-step functional group reaction |
| CN102964580A (en) * | 2012-10-31 | 2013-03-13 | 大连理工大学 | Linear comb polylactic acid and preparation method thereof |
| CN108341940A (en) * | 2018-02-12 | 2018-07-31 | 贵州大学 | A kind of preparation method of the efficiently long chain branching polylactic without gel |
| CN108359087A (en) * | 2018-02-12 | 2018-08-03 | 贵州大学 | Low melting point branched polylactic acid and preparation method thereof |
| CN109836614A (en) * | 2019-01-31 | 2019-06-04 | 中粮集团有限公司 | Composite thermal stabilizer, the method for lactide ring-opening polymerisation production polylactic acid and polylactic acid and application |
| CN110041466A (en) * | 2019-05-08 | 2019-07-23 | 湘潭大学 | A kind of high fondant-strength poly-lactic acid material and preparation method thereof |
| CN113265029A (en) * | 2020-11-26 | 2021-08-17 | 汕头市三马塑胶制品有限公司 | Long-chain branched polylactic acid with high melt strength and excellent processing fluidity and preparation method thereof |
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2009
- 2009-07-16 CN CNA2009100549037A patent/CN101597374A/en active Pending
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102453250A (en) * | 2010-10-25 | 2012-05-16 | 中国石油化工股份有限公司 | Method for preparing long chain branched polylactic resin by combining two-step functional group reaction |
| CN102453250B (en) * | 2010-10-25 | 2013-06-05 | 中国石油化工股份有限公司 | Method for preparing long chain branched polylactic resin by combining two-step functional group reaction |
| CN102964580A (en) * | 2012-10-31 | 2013-03-13 | 大连理工大学 | Linear comb polylactic acid and preparation method thereof |
| CN108341940A (en) * | 2018-02-12 | 2018-07-31 | 贵州大学 | A kind of preparation method of the efficiently long chain branching polylactic without gel |
| CN108359087A (en) * | 2018-02-12 | 2018-08-03 | 贵州大学 | Low melting point branched polylactic acid and preparation method thereof |
| CN108341940B (en) * | 2018-02-12 | 2020-05-12 | 贵州大学 | Preparation method of efficient gel-free long-chain branched polylactic acid |
| CN109836614A (en) * | 2019-01-31 | 2019-06-04 | 中粮集团有限公司 | Composite thermal stabilizer, the method for lactide ring-opening polymerisation production polylactic acid and polylactic acid and application |
| CN110041466A (en) * | 2019-05-08 | 2019-07-23 | 湘潭大学 | A kind of high fondant-strength poly-lactic acid material and preparation method thereof |
| CN110041466B (en) * | 2019-05-08 | 2022-01-25 | 湘潭大学 | High-melt-strength polylactic acid material and preparation method thereof |
| CN113265029A (en) * | 2020-11-26 | 2021-08-17 | 汕头市三马塑胶制品有限公司 | Long-chain branched polylactic acid with high melt strength and excellent processing fluidity and preparation method thereof |
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