CN114274404B - Preparation method of full-biodegradation starch-based plastic master batch - Google Patents
Preparation method of full-biodegradation starch-based plastic master batch Download PDFInfo
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- CN114274404B CN114274404B CN202111508497.4A CN202111508497A CN114274404B CN 114274404 B CN114274404 B CN 114274404B CN 202111508497 A CN202111508497 A CN 202111508497A CN 114274404 B CN114274404 B CN 114274404B
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- 229920002472 Starch Polymers 0.000 title claims abstract description 157
- 235000019698 starch Nutrition 0.000 title claims abstract description 153
- 239000008107 starch Substances 0.000 title claims abstract description 153
- 239000004594 Masterbatch (MB) Substances 0.000 title claims abstract description 45
- 239000004033 plastic Substances 0.000 title claims abstract description 43
- 229920003023 plastic Polymers 0.000 title claims abstract description 43
- 238000002360 preparation method Methods 0.000 title claims abstract description 28
- 238000006065 biodegradation reaction Methods 0.000 title claims abstract description 22
- 239000000203 mixture Substances 0.000 claims abstract description 59
- 239000004014 plasticizer Substances 0.000 claims abstract description 52
- 229920000229 biodegradable polyester Polymers 0.000 claims abstract description 40
- 239000004622 biodegradable polyester Substances 0.000 claims abstract description 40
- 238000002156 mixing Methods 0.000 claims abstract description 32
- 229920000728 polyester Polymers 0.000 claims abstract description 32
- 239000004970 Chain extender Substances 0.000 claims abstract description 30
- 239000000314 lubricant Substances 0.000 claims abstract description 30
- 239000012752 auxiliary agent Substances 0.000 claims abstract description 22
- 150000005846 sugar alcohols Polymers 0.000 claims abstract description 15
- 239000000463 material Substances 0.000 claims abstract description 13
- 239000000126 substance Substances 0.000 claims abstract description 9
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 claims description 28
- 229920005862 polyol Polymers 0.000 claims description 16
- 150000003077 polyols Chemical class 0.000 claims description 16
- 238000000034 method Methods 0.000 claims description 14
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims description 12
- FBPFZTCFMRRESA-FSIIMWSLSA-N D-Glucitol Natural products OC[C@H](O)[C@H](O)[C@@H](O)[C@H](O)CO FBPFZTCFMRRESA-FSIIMWSLSA-N 0.000 claims description 11
- FBPFZTCFMRRESA-JGWLITMVSA-N D-glucitol Chemical compound OC[C@H](O)[C@@H](O)[C@H](O)[C@H](O)CO FBPFZTCFMRRESA-JGWLITMVSA-N 0.000 claims description 11
- 239000000600 sorbitol Substances 0.000 claims description 11
- VBICKXHEKHSIBG-UHFFFAOYSA-N 1-monostearoylglycerol Chemical compound CCCCCCCCCCCCCCCCCC(=O)OCC(O)CO VBICKXHEKHSIBG-UHFFFAOYSA-N 0.000 claims description 10
- 239000007822 coupling agent Substances 0.000 claims description 8
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims description 7
- 238000000354 decomposition reaction Methods 0.000 claims description 6
- UQLDLKMNUJERMK-UHFFFAOYSA-L di(octadecanoyloxy)lead Chemical compound [Pb+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O UQLDLKMNUJERMK-UHFFFAOYSA-L 0.000 claims description 6
- UVCJGUGAGLDPAA-UHFFFAOYSA-N ensulizole Chemical compound N1C2=CC(S(=O)(=O)O)=CC=C2N=C1C1=CC=CC=C1 UVCJGUGAGLDPAA-UHFFFAOYSA-N 0.000 claims description 6
- 229920009537 polybutylene succinate adipate Polymers 0.000 claims description 6
- 229920001896 polybutyrate Polymers 0.000 claims description 6
- UPMLOUAZCHDJJD-UHFFFAOYSA-N 4,4'-Diphenylmethane Diisocyanate Chemical compound C1=CC(N=C=O)=CC=C1CC1=CC=C(N=C=O)C=C1 UPMLOUAZCHDJJD-UHFFFAOYSA-N 0.000 claims description 5
- UAUDZVJPLUQNMU-UHFFFAOYSA-N Erucasaeureamid Natural products CCCCCCCCC=CCCCCCCCCCCCC(N)=O UAUDZVJPLUQNMU-UHFFFAOYSA-N 0.000 claims description 5
- UAUDZVJPLUQNMU-KTKRTIGZSA-N erucamide Chemical group CCCCCCCC\C=C/CCCCCCCCCCCC(N)=O UAUDZVJPLUQNMU-KTKRTIGZSA-N 0.000 claims description 5
- 229940075507 glyceryl monostearate Drugs 0.000 claims description 5
- 239000001788 mono and diglycerides of fatty acids Substances 0.000 claims description 5
- OUPZKGBUJRBPGC-UHFFFAOYSA-N 1,3,5-tris(oxiran-2-ylmethyl)-1,3,5-triazinane-2,4,6-trione Chemical compound O=C1N(CC2OC2)C(=O)N(CC2OC2)C(=O)N1CC1CO1 OUPZKGBUJRBPGC-UHFFFAOYSA-N 0.000 claims description 4
- 229920002261 Corn starch Polymers 0.000 claims description 4
- 240000003183 Manihot esculenta Species 0.000 claims description 4
- 235000016735 Manihot esculenta subsp esculenta Nutrition 0.000 claims description 4
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical group [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 4
- 150000004645 aluminates Chemical class 0.000 claims description 4
- 239000007864 aqueous solution Substances 0.000 claims description 4
- 239000008120 corn starch Substances 0.000 claims description 4
- 229920000520 poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Polymers 0.000 claims description 4
- 229920001592 potato starch Polymers 0.000 claims description 4
- 229940100445 wheat starch Drugs 0.000 claims description 4
- VLDPXPPHXDGHEW-UHFFFAOYSA-N 1-chloro-2-dichlorophosphoryloxybenzene Chemical compound ClC1=CC=CC=C1OP(Cl)(Cl)=O VLDPXPPHXDGHEW-UHFFFAOYSA-N 0.000 claims description 3
- TXBCBTDQIULDIA-UHFFFAOYSA-N 2-[[3-hydroxy-2,2-bis(hydroxymethyl)propoxy]methyl]-2-(hydroxymethyl)propane-1,3-diol Chemical compound OCC(CO)(CO)COCC(CO)(CO)CO TXBCBTDQIULDIA-UHFFFAOYSA-N 0.000 claims description 3
- 229920001213 Polysorbate 20 Polymers 0.000 claims description 3
- ZJCCRDAZUWHFQH-UHFFFAOYSA-N Trimethylolpropane Chemical compound CCC(CO)(CO)CO ZJCCRDAZUWHFQH-UHFFFAOYSA-N 0.000 claims description 3
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims description 3
- 239000004202 carbamide Substances 0.000 claims description 3
- 238000002844 melting Methods 0.000 claims description 3
- 230000008018 melting Effects 0.000 claims description 3
- DTOBMOSGTHNELI-UHFFFAOYSA-N oxiran-2-ylmethyl 5-phenylpenta-2,4-dienoate Chemical group C=1C=CC=CC=1C=CC=CC(=O)OCC1CO1 DTOBMOSGTHNELI-UHFFFAOYSA-N 0.000 claims description 3
- WXZMFSXDPGVJKK-UHFFFAOYSA-N pentaerythritol Chemical compound OCC(CO)(CO)CO WXZMFSXDPGVJKK-UHFFFAOYSA-N 0.000 claims description 3
- 239000000256 polyoxyethylene sorbitan monolaurate Substances 0.000 claims description 3
- 235000010486 polyoxyethylene sorbitan monolaurate Nutrition 0.000 claims description 3
- 229940068977 polysorbate 20 Drugs 0.000 claims description 3
- LENZDBCJOHFCAS-UHFFFAOYSA-N tris Chemical compound OCC(N)(CO)CO LENZDBCJOHFCAS-UHFFFAOYSA-N 0.000 claims description 3
- 229960000281 trometamol Drugs 0.000 claims description 3
- AGNTUZCMJBTHOG-UHFFFAOYSA-N 3-[3-(2,3-dihydroxypropoxy)-2-hydroxypropoxy]propane-1,2-diol Chemical compound OCC(O)COCC(O)COCC(O)CO AGNTUZCMJBTHOG-UHFFFAOYSA-N 0.000 claims description 2
- WOKDXPHSIQRTJF-UHFFFAOYSA-N 3-[3-[3-[3-[3-[3-[3-[3-[3-(2,3-dihydroxypropoxy)-2-hydroxypropoxy]-2-hydroxypropoxy]-2-hydroxypropoxy]-2-hydroxypropoxy]-2-hydroxypropoxy]-2-hydroxypropoxy]-2-hydroxypropoxy]-2-hydroxypropoxy]propane-1,2-diol Chemical compound OCC(O)COCC(O)COCC(O)COCC(O)COCC(O)COCC(O)COCC(O)COCC(O)COCC(O)COCC(O)CO WOKDXPHSIQRTJF-UHFFFAOYSA-N 0.000 claims description 2
- GPLRAVKSCUXZTP-UHFFFAOYSA-N diglycerol Chemical compound OCC(O)COCC(O)CO GPLRAVKSCUXZTP-UHFFFAOYSA-N 0.000 claims description 2
- -1 hexaglycerol Chemical compound 0.000 claims description 2
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 claims description 2
- 229940059574 pentaerithrityl Drugs 0.000 claims description 2
- 229960002920 sorbitol Drugs 0.000 claims description 2
- FPVVYTCTZKCSOJ-UHFFFAOYSA-N Ethylene glycol distearate Chemical compound CCCCCCCCCCCCCCCCCC(=O)OCCOC(=O)CCCCCCCCCCCCCCCCC FPVVYTCTZKCSOJ-UHFFFAOYSA-N 0.000 claims 1
- 238000001816 cooling Methods 0.000 abstract description 9
- 239000000779 smoke Substances 0.000 abstract description 3
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- 150000002978 peroxides Chemical class 0.000 description 8
- 230000015556 catabolic process Effects 0.000 description 7
- 238000006731 degradation reaction Methods 0.000 description 7
- FPYJFEHAWHCUMM-UHFFFAOYSA-N maleic anhydride Chemical compound O=C1OC(=O)C=C1 FPYJFEHAWHCUMM-UHFFFAOYSA-N 0.000 description 7
- 239000002994 raw material Substances 0.000 description 7
- 229920000881 Modified starch Polymers 0.000 description 6
- 239000004368 Modified starch Substances 0.000 description 6
- 235000019426 modified starch Nutrition 0.000 description 6
- 239000000047 product Substances 0.000 description 6
- 229920000704 biodegradable plastic Polymers 0.000 description 5
- 238000010096 film blowing Methods 0.000 description 5
- 229920005989 resin Polymers 0.000 description 5
- 239000011347 resin Substances 0.000 description 5
- 239000003795 chemical substances by application Substances 0.000 description 3
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- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 2
- 238000004132 cross linking Methods 0.000 description 2
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- 229910052739 hydrogen Inorganic materials 0.000 description 2
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- RKISUIUJZGSLEV-UHFFFAOYSA-N n-[2-(octadecanoylamino)ethyl]octadecanamide Chemical compound CCCCCCCCCCCCCCCCCC(=O)NCCNC(=O)CCCCCCCCCCCCCCCCC RKISUIUJZGSLEV-UHFFFAOYSA-N 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 101710179738 6,7-dimethyl-8-ribityllumazine synthase 1 Proteins 0.000 description 1
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- 101710137584 Lipoyl synthase 1, chloroplastic Proteins 0.000 description 1
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- 239000001569 carbon dioxide Substances 0.000 description 1
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- 238000006243 chemical reaction Methods 0.000 description 1
- 238000004939 coking Methods 0.000 description 1
- 238000009264 composting Methods 0.000 description 1
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- 229960005150 glycerol Drugs 0.000 description 1
- 238000005469 granulation Methods 0.000 description 1
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Abstract
The invention provides a preparation method of a full-biodegradation starch-based plastic master batch, which comprises the following steps: (1) Uniformly mixing starch, a substance A and a lubricant to obtain a starch auxiliary agent mixture, and feeding the starch auxiliary agent mixture into a double-screw extruder through a main feed; the mass ratio of the starch to the substance A is 100:1-20; substance A is a plasticizer or a mixture of a plasticizer and a co-plasticizer; (2) Using an internal mixer to carry out banburying on biodegradable polyester, polyalcohol and chain extender with the mass ratio of 100:1-10:0.1-5 to obtain polyhydroxy branched polyester, and sending the polyhydroxy branched polyester into a double-screw extruder through single-screw side feeding to be mixed with starch auxiliary agent mixture; (3) The materials are extruded by a double-screw extruder, and then are subjected to bracing, air cooling and granulating to obtain the full-biodegradation starch-based plastic master batch. The preparation method is simple, can reduce the plasticizer required by plasticizing the starch, reduce the smoke generated during downstream processing, and simultaneously reduce the greasy feeling of the film surface of the product.
Description
Technical Field
The invention belongs to the technical field of processing of biodegradable polyester materials, and relates to a preparation method of a full-biodegradable starch-based plastic master batch.
Background
With the rise of electronic commerce, takeaway and logistics, the consumption of disposable tableware and disposable packaging film bags is rapidly increased, and white pollution is increasingly serious. Biodegradable plastics are increasingly important, but the price of the biodegradable plastics is generally high at present, so that the large-scale popularization of the biodegradable plastics is severely restricted. The starch source plant has the great advantages of regeneration, full degradation and low price, and has great application prospect when being used together with biodegradable plastics. However, starch is a polysaccharide molecular structure, contains a large number of hydroxyl groups, and forms a large number of intermolecular and intramolecular hydrogen bonds between the hydroxyl groups, so that the melting temperature is higher than the decomposition temperature, and therefore, the traditional starch plasticizing treatment needs more plasticizer (such as glycerol or sorbitol, and the total amount of the plasticizer is 20% -30% of the starch content) so that the plasticizer is separated out when the starch is used at the downstream.
In order to reduce the amount of plasticizer used, some prior art uses modified starch, but the cost of modified starch is much higher than that of the original starch; some prior arts use modified starch, namely, a graft is introduced on the starch to turn the starch into hydrophobic, so as to improve the compatibility of the starch and polyester, reduce the usage amount of a plasticizer, for example, peroxide DCP is used for grafting maleic anhydride on the starch in the patent CN200610025008.9, so as to prepare a full-biodegradation grafted starch master batch, but the grafting of the maleic anhydride needs to use the peroxide to open double bonds of the maleic anhydride to generate free radicals to form C-C bonds with a grafted main chain, but the peroxide also causes the grafted main chain to generate free radicals, so that a crosslinking phenomenon is generated, the degradation performance of the starch or the degradation resin is reduced after the starch or the degradation resin is crosslinked, and the grafting process of the maleic anhydride also needs to purify and remove ungrafted maleic anhydride, so that the cost is further increased; in other prior art, a graft (such as PLA grafted maleic anhydride) is introduced into the polyester as a compatibilizer to improve the compatibility of starch and the polyester, so as to achieve the effect of reducing the usage amount of plasticizer, for example, in patent CN201910295859.2, a maleic anhydride graft POE- & MA is used to prepare starch master batch, which also has the above problems.
Therefore, the research on the preparation method of the full-biodegradation starch-based plastic master batch which has low cost, small using amount of plasticizer and does not need peroxide has very important significance.
Disclosure of Invention
The invention aims to solve the problems in the prior art and provides a preparation method of a full-biodegradation starch-based plastic master batch, and in particular, the invention solves the problems of high cost, large using amount of plasticizer and peroxide need in the prior art by modifying biodegradable polyester into polyhydroxy branched polyester with good starch compatibility and then blending the polyhydroxy branched polyester with starch to produce the starch master batch.
In order to achieve the above object, the present invention is as follows:
The preparation method of the full-biodegradation starch-based plastic master batch comprises the following steps:
(1) Uniformly mixing starch, a substance A and a lubricant (if the starch is degraded or carbonized by thermal shearing without adding the lubricant) to obtain a starch auxiliary agent mixture, and feeding the starch auxiliary agent mixture into a double-screw extruder through a main feed; the mass ratio of the starch to the substance A is 100:1-20; substance A is a plasticizer or a mixture of a plasticizer and a co-plasticizer;
(2) Using an internal mixer to carry out internal mixing on biodegradable polyester, polyalcohol and chain extender with the mass ratio of 100:1-10:0.1-5 to obtain polyhydroxy branched polyester (hydroxyl end groups of the biodegradable polyester are connected with the polyalcohol through the chain extender to form the biodegradable polyester with polyhydroxy end groups in the internal mixing process, and the polyhydroxy end groups of the biodegradable polyester can form hydrogen bonds with starch so as to improve the compatibility of the polyester and the starch), and sending the polyhydroxy branched polyester into a double-screw extruder through single-screw side feeding to be mixed with starch auxiliary agent mixture; wherein the moisture content of the biodegradable polyester is less than 500ppm; the polyalcohol is grafted on the polyester, so that the polyalcohol cannot be separated out to cause smoke and oil on the film surface during film blowing;
(3) The materials are extruded by a double-screw extruder, and then are subjected to bracing, air cooling and granulating to obtain the full-biodegradation starch-based plastic master batch.
When the starch-based plastic master batch is prepared in the prior art, a large amount of plasticizer is often required to be added due to poor compatibility of starch and resin, and the method adopted in the prior art is as follows: 1) The use of modified starch has the problem of high cost; 2) The starch is grafted and modified to improve the compatibility with resin, and the problem is that peroxide is needed in the grafting and modifying process, which is not beneficial to degradation of the final product; 3) The compatibility of starch and resin is improved by adding the compatilizer, and the problem is that peroxide is needed in the preparation process of the compatilizer, so that the degradation of the final product is not facilitated. The invention provides a new method, which does not use modified starch, does not modify starch, does not add compatilizer, directly modifies polyester (peroxide is not used in the modification process) so as to improve the compatibility of the polyester and starch, and further reduces the addition amount of plasticizer.
As a preferable technical scheme:
In the preparation method of the full-biodegradable starch-based plastic master batch, in the step (1), the starch is corn starch, tapioca starch, potato starch or wheat starch; the plasticizer is more than one of glycerol, glycol, sorbitol aqueous solution, urea and citric acid; the auxiliary plasticizer is a titanate coupling agent or an aluminate coupling agent; the lubricant is erucamide, ethylene bisstearamide or glyceryl monostearate.
In the preparation method of the full-biodegradation starch-based plastic master batch, in the step (1), the mass ratio of starch to lubricant is 100:0.1-2; too much lubricant can cause the final product master batch to slip at a feeding port of a film blowing machine or slip in a screw rod when in use, and is unfavorable for heat sealing of film bags, and too few film bags have poor smoothness.
In the preparation method of the full-biodegradation starch-based plastic master batch, in the step (1), a high-speed mixer is adopted for mixing, the mixing time is 2-10 min, and the rotating speed is 500-1000 rpm; the excessive mixing time and rotating speed can cause the high-speed mixer to generate heat, the starch is burnt, and the feeding is not easy; too small results in uneven mixing of the materials.
In the preparation method of the full-biodegradable starch-based plastic master batch, in the step (2), the biodegradable polyester is one or more of PBAT, PBS, PBSA, PBST, PHA, PHBV, PCL and PLA; the polyalcohol is one or more of glycerol, diglycerol, triglycerol, hexaglycerol, decaglycerol, trometamol, sorbitol, polysorbate-20, pentaerythritol, dipentaerythritol and trimethylolpropane; the chain extender is styrene-acrylic acid-glycidyl ester, pyromellitic dianhydride, triglycidyl isocyanurate or diphenylmethane diisocyanate.
In the preparation method of the full biodegradable starch-based plastic master batch, in the step (2), the intrinsic viscosity of the biodegradable polyester is 0.3-1.62 dL/g; the intrinsic viscosity is small, which is not beneficial to chain extension, and the product viscosity is too large after chain extension with high viscosity to generate crosslinking.
In the step (2), firstly adding biodegradable polyester and polyol in the banburying process, banburying for 2-5 min under the temperature condition of 165-190 ℃ (the temperature is required by the reaction temperature of the chain extender), and then adding the chain extender for continuous banburying for 2-10 min; the excessive time and rotating speed of banburying can lead to thermal degradation of polyester, so that excessive carboxyl ends are caused, and the material is unevenly mixed due to too small carboxyl ends.
According to the preparation method of the full-biodegradable starch-based plastic master batch, the ratio of the main feed in the step (1) to the side feed in the step (2) is 1-6:1.
In the step (3), the length-diameter ratio of the double-screw extruder is 32-50:1, the set temperature is 10-30 ℃ higher than the melting point temperature of the biodegradable polyester and is lower than 160 ℃ (to prevent starch from coking), and the rotating speed of the host is 150-300 rpm.
According to the preparation method of the full-biodegradation starch-based plastic master batch, the 120-day decomposition rate of the full-biodegradation starch-based plastic master batch is more than or equal to 92%.
Advantageous effects
(1) According to the preparation method of the full-biodegradation starch-based plastic master batch, the biodegradable polyester is modified into the polyhydroxy branched polyester with good starch compatibility, and the polyhydroxy branched polyester is mixed with starch for granulation, so that the plasticizer required by plasticizing the starch can be obviously reduced, the smoke generated during downstream processing (such as film blowing) is reduced, and meanwhile, the greasy feeling of the film surface of a product is reduced;
(2) According to the preparation method of the full-biodegradable starch-based plastic master batch, disclosed by the invention, the master batch is generated by using starch in the process, so that the cost is greatly reduced compared with that of modified starch, and the popularization of biodegradable plastics is facilitated.
Detailed Description
The application is further described below in conjunction with the detailed description. It is to be understood that these examples are illustrative of the present application and are not intended to limit the scope of the present application. Furthermore, it should be understood that various changes and modifications can be made by one skilled in the art after reading the teachings of the present application, and such equivalents are intended to fall within the scope of the application as defined in the appended claims.
Moisture content: according to the B method in GB/T12006.2-2009, the heating temperature is 80 ℃, and the detection instrument is as follows: differential pressure micro moisture meter SF-1, electronic analytical balance XS104.
Intrinsic viscosity: the method is carried out according to the method A in GB/T14190-2017, and the detection instrument is as follows: full-automatic viscometer AVS370, electronic analytical balance XS105, magnetic stirring dry bath SD15-100, constant temperature oscillating water tank SW22.
Decomposition rate for 120 days: composting was performed as per astm d5988-2003 and the rate of decomposition was determined by testing the amount of carbon dioxide released.
Example 1
The preparation method of the full-biodegradation starch-based plastic master batch comprises the following specific steps:
(1) Preparing raw materials;
Starch: corn starch;
mixture of plasticizers and co-plasticizers: a mixture of glycerol and titanate coupling agent in a mass ratio of 1:0.09;
And (3) a lubricant: glyceryl monostearate;
biodegradable polyester: PBAT had an intrinsic viscosity of 1.55dL/g and a moisture content of 300ppm;
polyol: pentaerythritol;
chain extender: diphenylmethane diisocyanate;
(2) Uniformly mixing a mixture of starch, a plasticizer and a plasticizing aid with a lubricant by adopting a high-speed mixer for 10min at a rotating speed of 500rpm to obtain a starch auxiliary mixture, and feeding the starch auxiliary mixture into a double-screw extruder through a main feed; the mass ratio of the starch to the mixture of the plasticizer and the auxiliary plasticizer is 100:5.737; the mass ratio of the starch to the lubricant is 100:1.053;
(3) Using an internal mixer to carry out internal mixing on biodegradable polyester and polyalcohol for 5min at the temperature of 170 ℃, adding a chain extender to continue internal mixing for 5min to obtain polyhydroxy branched polyester, and feeding the polyhydroxy branched polyester into a double-screw extruder through single-screw side feeding to be mixed with starch auxiliary agent mixture; wherein the mass ratio of the biodegradable polyester to the polyol to the chain extender is 100:5.26:1.05; the ratio of the feeding amount of the main feeding in the step (2) to the side feeding in the step (3) is 3:1;
(4) Extruding the materials by a double-screw extruder, and then bracing, air-cooling and granulating to obtain all-biodegradable starch-based plastic master batch; wherein, the length-diameter ratio of the double-screw extruder is 32:1, the set temperature is 140 ℃, and the rotating speed of the host machine is 180rpm.
Example 2
The preparation method of the full-biodegradation starch-based plastic master batch comprises the following specific steps:
(1) Preparing raw materials;
Starch: tapioca starch;
Mixture of plasticizers and co-plasticizers: a mixture of aqueous sorbitol solution (70 wt% mass fraction) and titanate coupling agent in a mass ratio of 2:0.05;
and (3) a lubricant: ethylene bis-stearamide;
Biodegradable polyester: a mixture of PBAT and PHA in a mass ratio of 5:4.5; the intrinsic viscosity of PBAT was 1.55dL/g and the moisture content was 425ppm; PHA has an intrinsic viscosity of 1.2dL/g and a moisture content of 425ppm;
Polyol: sorbitol;
Chain extender: triglycidyl isocyanurate;
(2) Uniformly mixing a mixture of starch, a plasticizer and a plasticizing aid with a lubricant by adopting a high-speed mixer for 10min at 600rpm to obtain a starch auxiliary mixture, and feeding the starch auxiliary mixture into a double-screw extruder through a main feed; the mass ratio of the starch to the mixture of the plasticizer and the auxiliary plasticizer is 100:11.39; the mass ratio of the starch to the lubricant is 100:0.556;
(3) Using an internal mixer to carry out internal mixing on biodegradable polyester and polyalcohol for 5min at the temperature of 180 ℃, adding a chain extender to continue internal mixing for 5min to obtain polyhydroxy branched polyester, and feeding the polyhydroxy branched polyester into a double-screw extruder through single-screw side feeding to be mixed with starch auxiliary agent mixture; wherein the mass ratio of the biodegradable polyester to the polyol to the chain extender is 100:5.26:1.05; the ratio of the feeding amount of the main feeding in the step (2) to the side feeding in the step (3) is 5:1;
(4) Extruding the materials by a double-screw extruder, and then bracing, air-cooling and granulating to obtain all-biodegradable starch-based plastic master batch; wherein, the length-diameter ratio of the double-screw extruder is 36:1, the set temperature is 135 ℃, and the rotating speed of the host machine is 200rpm.
Example 3
The preparation method of the full-biodegradation starch-based plastic master batch comprises the following specific steps:
(1) Preparing raw materials;
Starch: corn starch;
Mixture of plasticizers and co-plasticizers: a mixture of sorbitol aqueous solution (mass fraction 70 wt.%) in a mass ratio of 1:1:0.1, glycerol and aluminate coupling agent;
And (3) a lubricant: glyceryl monostearate;
Biodegradable polyester: a mixture of PCL and PLA in a mass ratio of 6.5:2.5; the intrinsic viscosity of PCL was 1.62dL/g, and the moisture content was 410ppm; PLA had an intrinsic viscosity of 1.5dL/g and a moisture content of 410ppm;
Polyol: sorbitol;
chain extender: diphenylmethane diisocyanate;
(2) Uniformly mixing a mixture of starch, a plasticizer and a plasticizing aid with a lubricant by adopting a high-speed mixer for 10min at a rotating speed of 800rpm to obtain a starch auxiliary mixture, and feeding the starch auxiliary mixture into a double-screw extruder through a main feed; the mass ratio of the starch to the mixture of the plasticizer and the auxiliary plasticizer is 100:11.667; the mass ratio of the starch to the lubricant is 100:0.556;
(3) Using an internal mixer to carry out internal mixing on biodegradable polyester and polyalcohol for 5min at the temperature of 170 ℃, adding a chain extender to continue internal mixing for 5min to obtain polyhydroxy branched polyester, and feeding the polyhydroxy branched polyester into a double-screw extruder through single-screw side feeding to be mixed with starch auxiliary agent mixture; wherein the mass ratio of the biodegradable polyester to the polyol to the chain extender is 100:11.11:1.67; the ratio of the feeding amount of the main feeding in the step (2) to the feeding amount of the side feeding in the step (3) is 2:1;
(4) Extruding the materials by a double-screw extruder, and then bracing, air-cooling and granulating to obtain all-biodegradable starch-based plastic master batch; wherein, the length-diameter ratio of the double-screw extruder is 42:1, the set temperature is 150 ℃, and the rotating speed of the host machine is 220rpm.
Example 4
The preparation method of the full-biodegradation starch-based plastic master batch comprises the following specific steps:
(1) Preparing raw materials;
starch: a mixture of wheat starch and tapioca starch in a mass ratio of 16:2;
Mixture of plasticizers and co-plasticizers: a mixture of sorbitol aqueous solution (mass fraction 70 wt.%) in a mass ratio of 2:0.05:0.15, citric acid and aluminate coupling agent;
And (3) a lubricant: glyceryl monostearate;
biodegradable polyester: a mixture of PHA and PLA in a mass ratio of 8.5:1; PHA has an intrinsic viscosity of 1.2dL/g and a moisture content of 355ppm; PLA had an intrinsic viscosity of 1.5dL/g and a moisture content of 355ppm;
Polyol: sorbitol;
chain extender: pyromellitic dianhydride;
(2) Uniformly mixing a mixture of starch, a plasticizer and a plasticizing aid with a lubricant by adopting a high-speed mixer for 10min at a rotating speed of 700rpm to obtain a starch auxiliary mixture, and feeding the starch auxiliary mixture into a double-screw extruder through a main feed; the mass ratio of the starch to the mixture of the plasticizer and the auxiliary plasticizer is 100:12.22; the mass ratio of the starch to the lubricant is 100:0.833;
(3) Using an internal mixer to carry out internal mixing on biodegradable polyester and polyalcohol for 5min at the temperature of 165 ℃, adding a chain extender to continue internal mixing for 5min to obtain polyhydroxy branched polyester, and feeding the polyhydroxy branched polyester into a double-screw extruder through single-screw side feeding to be mixed with starch auxiliary agent mixture; wherein the mass ratio of the biodegradable polyester to the polyol to the chain extender is 100:5.26:1.05; the ratio of the feeding amount of the main feeding in the step (2) to the side feeding in the step (3) is 3:1;
(4) Extruding the materials by a double-screw extruder, and then bracing, air-cooling and granulating to obtain all-biodegradable starch-based plastic master batch; wherein, the length-diameter ratio of the double-screw extruder is 45:1, the set temperature is 160 ℃, and the rotating speed of the host machine is 250rpm.
Example 5
The preparation method of the full-biodegradation starch-based plastic master batch comprises the following specific steps:
(1) Preparing raw materials;
starch: potato starch;
And (3) plasticizing agent: urea;
And (3) a lubricant: erucamide;
Biodegradable polyester: a mixture of PBS and PBSA in a mass ratio of 1:1; the PBS had an intrinsic viscosity of 1.59dL/g and a moisture content of 320ppm; the intrinsic viscosity of PBSA was 1.4dL/g and the moisture content was 320ppm;
polyol: a mixture of glycerol, tromethamine and polysorbate-20 in a mass ratio of 1:1:1;
chain extender: styrene-acrylic acid-glycidyl ester;
(2) Uniformly mixing starch, a plasticizer and a lubricant by adopting a high-speed mixer for 2min at a rotating speed of 900rpm to obtain a starch auxiliary agent mixture, and feeding the starch auxiliary agent mixture into a double-screw extruder through a main feed; the mass ratio of the starch to the plasticizer is 100:1; the mass ratio of the starch to the lubricant is 100:0.1;
(3) Using an internal mixer to carry out internal mixing on biodegradable polyester and polyalcohol for 2min at the temperature of 190 ℃, adding a chain extender to continue internal mixing for 2min to obtain polyhydroxy branched polyester, and feeding the polyhydroxy branched polyester into a double-screw extruder through single-screw side feeding to be mixed with starch auxiliary agent mixture; wherein the mass ratio of the biodegradable polyester to the polyol to the chain extender is 100:1:0.1; the ratio of the feeding amount of the main feeding in the step (2) to the side feeding in the step (3) is 1:1;
(4) Extruding the materials by a double-screw extruder, and then bracing, air-cooling and granulating to obtain all-biodegradable starch-based plastic master batch; wherein, the length-diameter ratio of the double-screw extruder is 47:1, the set temperature is 160 ℃, and the rotating speed of the host machine is 150rpm.
Example 6
The preparation method of the full-biodegradation starch-based plastic master batch comprises the following specific steps:
(1) Preparing raw materials;
Starch: wheat starch;
And (3) plasticizing agent: ethylene glycol;
And (3) a lubricant: erucamide;
Biodegradable polyester: a mixture of PBST and PHBV in a mass ratio of 1:1; the intrinsic viscosity of PBST was 1.47dL/g, and the moisture content was 405ppm; PHBV has an intrinsic viscosity of 1.02dL/g and a moisture content of 405ppm;
polyol: a mixture of dimer glycerin, trimer glycerin, hexapolyglycerin, and decapolyglycerin in a mass ratio of 1:1:1:1;
chain extender: diphenylmethane diisocyanate;
(2) Uniformly mixing starch, a plasticizer and a lubricant by adopting a high-speed mixer for 3min at a rotating speed of 850rpm to obtain a starch auxiliary agent mixture, and feeding the starch auxiliary agent mixture into a double-screw extruder through a main feed; the mass ratio of the starch to the plasticizer is 100:10; the mass ratio of the starch to the lubricant is 100:1;
(3) Using an internal mixer to carry out internal mixing on biodegradable polyester and polyalcohol for 3min at the temperature of 175 ℃, adding a chain extender to continue internal mixing for 5min to obtain polyhydroxy branched polyester, and feeding the polyhydroxy branched polyester into a double-screw extruder through single-screw side feeding to be mixed with starch auxiliary agent mixture; wherein the mass ratio of the biodegradable polyester to the polyol to the chain extender is 100:6:0.3; the ratio of the feeding amount of the main feeding in the step (2) to the side feeding in the step (3) is 4:1;
(4) Extruding the materials by a double-screw extruder, and then bracing, air-cooling and granulating to obtain all-biodegradable starch-based plastic master batch; wherein, the length-diameter ratio of the double-screw extruder is 49:1, the set temperature is 130 ℃, and the rotating speed of the host machine is 200rpm.
Example 7
The preparation method of the full-biodegradation starch-based plastic master batch comprises the following specific steps:
(1) Preparing raw materials;
starch: potato starch;
and (3) plasticizing agent: citric acid;
And (3) a lubricant: erucamide;
Biodegradable polyester: a mixture of PBST and PBSA in a mass ratio of 1:1; the intrinsic viscosity of PBST was 1.47dL/g, and the moisture content was 386ppm; the intrinsic viscosity of PBSA was 1.4dL/g, and the moisture content was 386ppm;
Polyol: a mixture of dipentaerythritol and trimethylolpropane in a mass ratio of 1:1;
Chain extender: triglycidyl isocyanurate;
(2) Uniformly mixing starch, a plasticizer and a lubricant by adopting a high-speed mixer for 5min at a rotating speed of 1000rpm to obtain a starch auxiliary agent mixture, and feeding the starch auxiliary agent mixture into a double-screw extruder through a main feed; the mass ratio of the starch to the plasticizer is 100:20; the mass ratio of the starch to the lubricant is 100:2;
(3) Using an internal mixer to carry out internal mixing on biodegradable polyester and polyalcohol for 5min at the temperature of 180 ℃, adding a chain extender to continue internal mixing for 10min to obtain polyhydroxy branched polyester, and feeding the polyhydroxy branched polyester into a double-screw extruder through single-screw side feeding to be mixed with starch auxiliary agent mixture; wherein the mass ratio of the biodegradable polyester to the polyol to the chain extender is 100:10:5; the ratio of the feeding amount of the main feeding in the step (2) to the side feeding in the step (3) is 6:1;
(4) Extruding the materials by a double-screw extruder, and then bracing, air-cooling and granulating to obtain all-biodegradable starch-based plastic master batch; wherein, the length-diameter ratio of the double-screw extruder is 50:1, the set temperature is 130 ℃, and the rotating speed of the host machine is 300rpm.
The full biodegradable starch-based plastic master batches prepared in examples 1 to 7 were mixed with PBAT in a certain proportion to blow a film, the blow-up ratio was 2.5, and a biodegradable film product with a starch content of 25wt% was obtained. The biodegradable film products and the commercial starch film (golden hair C200S 21D) products of examples 1 to 7 were specified according to GB/T1040.1-2018 and GB/T1040.3-2006, the sample width was 15mm, the initial distance between clamps was 50mm, the test speed was (500.+ -. 50) mm/min until the sample broke, the maximum tensile load was measured to the nearest 0.01N, and the tensile strength was calculated; the film blowing machine is used for: small experimental film blowing machine: HTBS-25; the using instrument is as follows: the film material testing machine LS-1, the sample preparation film punching machine is: the film properties of the electric sheet punch CP-25-III are shown in Table 1:
TABLE 1
As can be seen from table 1, the tensile strength and elongation at break of the films prepared from the full biodegradable starch-based plastic masterbatches of examples 1, 2,4, 5, 6, and 7 were better than the commercial starch film data, and the data of the films prepared from the full biodegradable starch-based plastic masterbatches of example 3 were close to the commercial starch film data. The invention reduces the using amount of the plasticizer and ensures normal use performance of the biodegradable film.
The decomposition rates of the biodegradable film products and the commercial starch film (golden hair C200S 21D) of examples 1 to 7 for 120 days are shown in Table 2.
TABLE 2
Claims (4)
1. The preparation method of the full-biodegradation starch-based plastic master batch is characterized by comprising the following steps of:
(1) Uniformly mixing starch, a substance A and a lubricant to obtain a starch auxiliary agent mixture, and feeding the starch auxiliary agent mixture into a double-screw extruder through a main feed; the mass ratio of the starch to the substance A is 100:1-20, and the mass ratio of the starch to the lubricant is 100:0.1-2; substance A is a plasticizer or a mixture of a plasticizer and a co-plasticizer;
The starch is corn starch, tapioca starch, potato starch or wheat starch; the plasticizer is more than one of glycerol, glycol, sorbitol aqueous solution, urea and citric acid; the auxiliary plasticizer is a titanate coupling agent or an aluminate coupling agent; the lubricant is erucamide, ethylene distearate or glyceryl monostearate;
Mixing by a high-speed mixer for 2-10 min at 500-1000 rpm;
(2) Using an internal mixer to carry out banburying on biodegradable polyester, polyalcohol and chain extender with the mass ratio of 100:1-10:0.1-5 to obtain polyhydroxy branched polyester, and sending the polyhydroxy branched polyester into a double-screw extruder through single-screw side feeding to be mixed with starch auxiliary agent mixture; wherein the moisture content of the biodegradable polyester is less than 500ppm;
the biodegradable polyester is one or more of PBAT, PBS, PBSA, PBST, PHA, PHBV, PCL and PLA; the polyalcohol is one or more of glycerol, diglycerol, triglycerol, hexaglycerol, decaglycerol, trometamol, sorbitol, polysorbate-20, pentaerythritol, dipentaerythritol and trimethylolpropane; the chain extender is styrene-acrylic acid-glycidyl ester, pyromellitic dianhydride, triglycidyl isocyanurate or diphenylmethane diisocyanate;
the intrinsic viscosity of the biodegradable polyester is 0.3-1.62 dL/g;
In the banburying process, firstly adding biodegradable polyester and polyol, banburying for 2-5 min at the temperature of 165-190 ℃, and then adding a chain extender to continue banburying for 2-10 min;
(3) The materials are extruded by a double-screw extruder to obtain the full-biodegradable starch-based plastic master batch.
2. The method for preparing the full biodegradable starch-based plastic master batch according to claim 1, wherein the ratio of the main feed in the step (1) to the side feed in the step (2) is 1-6:1.
3. The preparation method of the full-biodegradable starch-based plastic master batch according to claim 1, wherein in the step (3), the length-diameter ratio of the twin-screw extruder is 32-50:1, the set temperature is 10-30 ℃ higher than the melting point temperature of biodegradable polyester and is lower than 160 ℃, and the host rotation speed is 150-300 rpm.
4. The method for preparing the full-biodegradable starch-based plastic master batch according to claim 1, wherein the 120-day decomposition rate of the full-biodegradable starch-based plastic master batch is more than or equal to 92%.
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