CN113429762A - Starch/polylactic acid/PBAT nano composite material and preparation method thereof - Google Patents
Starch/polylactic acid/PBAT nano composite material and preparation method thereof Download PDFInfo
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- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L67/00—Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Compositions of derivatives of such polymers
- C08L67/04—Polyesters derived from hydroxycarboxylic acids, e.g. lactones
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
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- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2205/00—Polymer mixtures characterised by other features
- C08L2205/02—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group
- C08L2205/025—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure
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- C08L2205/00—Polymer mixtures characterised by other features
- C08L2205/24—Crystallisation aids
Abstract
The invention discloses a starch/polylactic acid/PBAT nano composite material and a preparation method thereof, wherein the starch/polylactic acid/PBAT nano composite material comprises the following raw materials in percentage by weight: 20-40% of polylactic acid copolymer, 5-25% of levorotatory polylactic acid, 10-20% of starch master batch, 20-40% of talcum powder, 1-2% of chain extender, 0.2-0.4% of coupling agent, 4-6% of flexibilizer, 0.2-0.5% of nucleating agent, 0.2-0.6% of compound antioxidant and 0.5-1% of processing aid, mixing the dried raw materials in a high-speed mixer, fully stirring and uniformly dispersing the components, adding the mixed materials into a double-screw extruder for melt extrusion, cooling, air drying, granulating, strongly magnetizing and packaging the extruded materials to obtain a finished product, wherein the melt extrusion temperature is 160-200 ℃, the screw rotation speed is 300-500 r/min. According to the invention, through a series of component proportions and processing methods, the composite material has good high-temperature resistance, the mechanical property and the processing property are improved, and the problems of poor material compatibility and the like can be avoided.
Description
Technical Field
The invention relates to the technical field of high polymer materials, in particular to a starch/polylactic acid/PBAT nano composite material and a preparation method thereof.
Background
Polylactic acid (PLA) is a new bio-based and renewable biodegradable material made using starch as a base material, which is proposed by renewable plant resources. The biodegradable plastic has good biodegradability, can be completely degraded by microorganisms in the nature under specific conditions after being used, finally generates carbon dioxide and water, and realizes a sufficient environment-friendly effect under the condition of no environmental pollution.
In the prior art, polylactic acid is widely applied and can be applied to articles such as disposable tableware, shopping bags, clothing, diaper, and the like, and polymer materials formed by polymerizing the existing polylactic acid also have many defects along with the wide application:
1. poor high temperature resistance: the temperature resistance of degradable materials such as PLA and the like is poor, the defects of no temperature resistance, no oil resistance and the like generally exist in disposable tableware which is processed and produced by taking the degradable materials as raw materials, the function is greatly reduced, and a large number of defective products are caused by deformation and brittleness of the tableware in the transportation process;
2. the mechanical property is poor: the mechanical property of the degradable material is poor, and the performance requirement of the current market on plastics cannot be met, for example, the toughness of the PLA material is poor, the elongation at break of the PLA material is less than 10%, and the toughness of the polylactic acid restricts the application of the PLA material in other application fields such as the aspect that the PLA material needs plastic deformation under high pressure (such as a screw and a fixing plate).
3. Poor processability: the degradable material has some difficulties in processing due to performance factors such as crystallization temperature of the resin matrix.
In addition to the deficiencies in physical and processing properties, the degradation cycle of PLA materials is difficult to control, degradation is mainly by hydrolysis of the backbone containing ester groups, and the rate of degradation also depends on the degree of crystallinity, morphology, rate of water diffusion into the polymer, and the content of different stereoisomers in the polymer.
Disclosure of Invention
The invention aims to provide a starch/polylactic acid/PBAT nano composite material and a preparation method thereof, so as to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme: a starch/polylactic acid/PBAT nanocomposite material comprises the following raw materials in percentage by weight: 20-40% of polylactic acid copolymer, 5-25% of levorotatory polylactic acid, 10-20% of starch master batch, 20-40% of talcum powder, 1-2% of chain extender, 0.2-0.4% of coupling agent, 4-6% of flexibilizer, 0.2-0.5% of nucleating agent, 0.2-0.6% of compound antioxidant and 0.5-1% of processing aid.
Preferably, the fineness of the talcum powder is 10000-.
Preferably, the starch master batch contains 70-85% of starch by weight, and is prepared by low-temperature processing of an internal mixer, and the preparation method comprises the following steps:
s1, uniformly mixing 70-85% of starch, 10-20% of food-grade glycerol and 5-10% of food-grade silicone oil, putting into an internal mixer, controlling the temperature at 90-110 ℃, and uniformly mixing to form a viscous-state solid.
S2, transferring the viscous state solid into a double-wrist granulator by weighing and heating, extruding, air cooling, and granulating at 90-110 ℃.
Preferably, the toughening agent is an adipic acid-butylene terephthalate copolymer, and the nucleating agent is a sebacic acid diphenyl dihydrazide mixture.
Preferably, the processing aid is a hyperbranched resin or silicone.
Preferably, the preparation method of the levorotatory polylactic acid comprises the following steps: s1, lactide synthesis; s2, purifying; s3, polymerization of L-PLA.
Preferably, in the lactide synthesis: adding lactic acid into a three-neck flask, slowly heating to 110 ℃ under the protection of nitrogen atmosphere, dehydrating under normal pressure, heating to 140-160 ℃, adding a stannous octoate catalyst for reaction, removing water generated in the polycondensation reaction, quickly heating, continuously increasing the vacuum degree, and cracking the oligomer to generate lactide.
Preferably, the purification operation comprises the steps of hydrolyzing lactide, recrystallizing, after crystallization is completed, carrying out suction filtration, vacuum drying at 45 ℃ to constant mass, carrying out recrystallization 3-4 times, and carrying out vacuum low-temperature storage on the obtained lactide with the yield of about 75%.
Preferably, the polymerization step of the L-PLA is to use lactide as a monomer and stannous octoate as a catalyst, prepare a polylactic acid prepolymer through lactide ring-opening polymerization, and use protonic acid as a catalyst to polymerize the lactide ring-opening into the PLLA at the temperature of 40-60 ℃.
The invention also provides a preparation method of the starch/polylactic acid/PBAT nano composite material, which comprises the following steps:
s1, drying the polylactic acid and the starch masterbatch for 3-5 hours at 80 ℃, mixing the dried polylactic acid, the dried starch masterbatch, the levorotatory polylactic acid, the talcum powder, the chain extender, the coupling agent, the flexibilizer, the nucleating agent, the compound antioxidant and the processing aid in a high-speed mixer, and fully stirring and uniformly dispersing all the components.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
Compared with the prior art, the invention has the beneficial effects that:
compared with the prior art and products on the market, the starch/polylactic acid/PBAT nano composite material and the preparation method thereof improve the crystallization property of the composite material by adding the levorotatory PLLA as a nucleating agent, thereby achieving the purpose of improving the thermal deformation temperature without influencing the degradation efficiency, the prepared product not only has good high temperature resistance, but also can effectively widen the application field of the degradation material, such as high-temperature tableware and the like, introduce the nano material for modification, can effectively improve the mechanical property of the material, improve the processing property thereof by adding the proper 10000-plus-15000-mesh talcum powder as the nano material for blending, enable the material to be processed and molded more easily, the used processing equipment is the same as the traditional processing equipment, the equipment does not need to be changed, improve the production efficiency, reduce the production difficulty, use the prepared homopolymerized levorotatory PLA as the nucleating agent, use the levorotatory copolymerized PLA as the base material, can avoid poor compatibility of the material and is convenient for controlling the degradation rate of the material.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The starch/polylactic acid/PBAT nano composite material comprises the following raw materials in percentage by weight: 20-40% of transparent polylactic acid copolymer with the melt index of 10-20, 5-25% of levorotatory polylactic acid, 10-20% of starch master batch, 20-40% of talcum powder, 1-2% of chain extender, 0.2-0.4% of coupling agent, 4-6% of toughening agent, 0.2-0.5% of nucleating agent, 0.2-0.6% of compound antioxidant and 0.5-1% of processing aid.
Specifically, the fineness of the talcum powder is 10000-15000 meshes, which is different from the conventional talcum powder with the particle size of less than 1250 meshes.
Further, the starch master batch contains 70-85% of starch by weight, and is prepared by low-temperature processing of an internal mixer, and the specific preparation method comprises the following steps:
s1, uniformly mixing 70-85% of starch, 10-20% of food-grade glycerol and 5-10% of food-grade silicone oil, putting the mixture into an internal mixer, controlling the temperature to be 90-110 ℃, and forming a viscous-state solid after uniform internal mixing, wherein the starch can be common corn starch for use.
S2 transferring the viscous state solid into a double-wrist granulator, extruding, air cooling, granulating for later use, controlling the temperature at 90-110 ℃, and preparing without water cooling or contacting with water.
Further, the PBAT serving as a toughening agent is an adipic acid-butylene terephthalate copolymer.
Further, the nucleating agent is a mixture of sebacic acid diphenyl dihydrazide, the processing aid is hyperbranched resin or silicone, and the compound antioxidant is 1010/627A, wherein the ratio of the nucleating agent to the processing aid is 1: 1; the L-polylactic acid is in a transparent state, the melt index is 10-20, the melting point is more than 175 ℃, meanwhile, the chain extender can be used as Pasteur ADR4300, and the coupling agent can be selected from one of silane coupling agents KH550, KH560 and KH 792.
Further, the preparation method of the levorotatory polylactic acid comprises the following steps: s1, lactide synthesis; s2, purifying; s3, polymerization of L-PLA.
Further, in the lactide synthesis: adding a certain amount of lactic acid into a three-neck flask, slowly heating to 110 ℃ under the protection of nitrogen atmosphere, and dehydrating for a certain time under normal pressure to remove most of free water; heating to 140-160 deg.c, adding stannous octoate catalyst to certain vacuum degree, further reaction for some time to eliminate water produced in the polycondensation reaction; then quickly raising the temperature to over 180 ℃, continuously improving the vacuum degree, and cracking the oligomer to generate lactide.
Further, the purification operation is as follows: the lactide is first hydrolysed. Weighing crude lactide in a beaker, adding deionized water in proportion, stirring and hydrolyzing for a period of time at room temperature, carrying out suction filtration, dehydrating, carrying out vacuum drying at 45 ℃ for more than 12h, then carrying out recrystallization, weighing lactide after hydrolysis and drying, placing in the beaker, adding a recrystallization solvent ethyl acetate in proportion, stirring at 55 ℃ until the lactide is completely dissolved, standing to room temperature, placing in a refrigerator, cooling and crystallizing for 8-10 h, carrying out suction filtration after complete crystallization, carrying out vacuum drying at 45 ℃ to constant mass, carrying out recrystallization for 3-4 times, wherein the yield is about 75%, and carrying out vacuum low-temperature storage on the obtained lactide.
Further, the polymerization step of the L-PLA is to use lactide as a monomer and stannous octoate as a catalyst, prepare a polylactic acid prepolymer through lactide ring-opening polymerization, and use protonic acid as a catalyst to polymerize the lactide ring-opening at 40-60 ℃ to form PLLA.
In addition, the preparation method of the starch/polylactic acid/PBAT nano composite material comprises the following steps:
s1, drying the polylactic acid and the starch masterbatch for 3-5 hours at 80 ℃, mixing the dried polylactic acid, the dried starch masterbatch, the levorotatory polylactic acid, the talcum powder, the chain extender, the coupling agent, the flexibilizer, the nucleating agent, the compound antioxidant and the processing aid in a high-speed mixer, and fully stirring and uniformly dispersing all the components.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
Aiming at the different percentages of the components of the starch/polylactic acid/PBAT nanocomposite material, 8 groups of examples are carried out, and 4 groups of comparative experiments are carried out.
Example 1
The starch/polylactic acid/PBAT nanocomposite and the preparation method thereof of the embodiment are characterized in that S1, polylactic acid and starch masterbatch are dried for 3-5 hours at 80 ℃, 41.8% of dried transparent PLA polylactic acid copolymer with a melt index of 10-20, 10% of L-polylactic acid, 20% of dried starch masterbatch, 20% of 10000 meshes of talcum powder, 1.5% of chain extender, 0.2% of KH550 coupling agent, 5% of PBAT toughening agent, 0% of nucleating agent, 0.5% of compound antioxidant and 1% of processing aid are mixed in a high-speed mixer, so that all components are fully stirred and uniformly dispersed.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
Example 2
The starch/polylactic acid/PBAT nanocomposite and the preparation method thereof of the embodiment are characterized in that S1, polylactic acid and starch masterbatch are dried for 3-5 hours at 80 ℃, 31.7% of dried transparent PLA polylactic acid copolymer with a melt index of 10-20, 10% of L-polylactic acid, 20% of dried starch masterbatch, 30% of 10000 meshes of talcum powder, 1.5% of chain extender, 0.3% of KH550 coupling agent, 5% of PBAT toughening agent, 0% of nucleating agent, 0.5% of compound antioxidant and 1% of processing aid are mixed in a high-speed mixer, so that all components are fully stirred and uniformly dispersed.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
Example 3
The starch/polylactic acid/PBAT nanocomposite and the preparation method thereof of the embodiment are characterized in that S1, polylactic acid and starch masterbatch are dried for 3-5 hours at 80 ℃, 21.6% of dried transparent PLA polylactic acid copolymer with a melt index of 10-20, 10% of L-polylactic acid, 20% of dried starch masterbatch, 40% of 10000 meshes of talcum powder, 1.5% of chain extender, 0.4% of KH550 coupling agent, 5% of PBAT toughening agent, 0% of nucleating agent, 0.5% of compound antioxidant and 1% of processing aid are mixed in a high-speed mixer, so that all components are fully stirred and uniformly dispersed.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
Example 4
The starch/polylactic acid/PBAT nanocomposite and the preparation method thereof of the embodiment are characterized in that S1, polylactic acid and starch masterbatch are dried for 3-5 hours at 80 ℃, 36.7% of dried transparent PLA polylactic acid copolymer with a melt index of 10-20, 5% of L-polylactic acid, 20% of dried starch masterbatch, 30% of 10000 meshes of talcum powder, 1.5% of chain extender, 0.3% of KH550 coupling agent, 5% of PBAT toughening agent, 0% of nucleating agent, 0.5% of compound antioxidant and 1% of processing aid are mixed in a high-speed mixer, so that all components are fully stirred and uniformly dispersed.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
Example 5
The starch/polylactic acid/PBAT nanocomposite and the preparation method thereof of the embodiment are characterized in that S1, polylactic acid and starch masterbatch are dried for 3-5 hours at 80 ℃, 26.7% of dried transparent PLA polylactic acid copolymer with a melt index of 10-20, 15% of L-polylactic acid, 20% of dried starch masterbatch, 30% of 10000 meshes of talcum powder, 1.5% of chain extender, 0.3% of KH550 coupling agent, 5% of PBAT toughening agent, 0% of nucleating agent, 0.5% of compound antioxidant and 1% of processing aid are mixed in a high-speed mixer, so that all components are fully stirred and uniformly dispersed.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
Example 6
The starch/polylactic acid/PBAT nanocomposite and the preparation method thereof of the embodiment are characterized in that S1, polylactic acid and starch masterbatch are dried for 3-5 hours at 80 ℃, 21.7% of dried transparent PLA polylactic acid copolymer with a melt index of 10-20, 20% of L-polylactic acid, 20% of dried starch masterbatch, 30% of 10000 meshes of talcum powder, 1.5% of chain extender, 0.3% of KH550 coupling agent, 5% of PBAT toughening agent, 0% of nucleating agent, 0.5% of compound antioxidant and 1% of processing aid are mixed in a high-speed mixer, so that all components are fully stirred and uniformly dispersed.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
Example 7
The starch/polylactic acid/PBAT nanocomposite and the preparation method thereof of the embodiment are characterized in that S1, polylactic acid and starch masterbatch are dried for 3-5 hours at 80 ℃, 41.7% of dried transparent PLA polylactic acid copolymer with a melt index of 10-20, 10% of L-polylactic acid, 10% of dried starch masterbatch, 30% of 10000 meshes of talcum powder, 1.5% of chain extender, 0.3% of KH550 coupling agent, 5% of PBAT toughening agent, 0% of nucleating agent, 0.5% of compound antioxidant and 1% of processing aid are mixed in a high-speed mixer, so that all components are fully stirred and uniformly dispersed.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
Example 8
The starch/polylactic acid/PBAT nanocomposite and the preparation method thereof of the embodiment are characterized in that S1, polylactic acid and starch masterbatch are dried for 3-5 hours at 80 ℃, 36.7% of dried transparent PLA polylactic acid copolymer with a melt index of 10-20, 10% of L-polylactic acid, 15% of dried starch masterbatch, 30% of 10000 meshes of talcum powder, 1.5% of chain extender, 0.3% of KH550 coupling agent, 5% of PBAT toughening agent, 0% of nucleating agent, 0.5% of compound antioxidant and 1% of processing aid are mixed in a high-speed mixer, so that all components are fully stirred and uniformly dispersed.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
Comparative example 1
The starch/polylactic acid/PBAT nano composite material and the preparation method thereof comprise S1, wherein, polylactic acid and starch master batches are dried for 3-5 hours at the temperature of 80 ℃, 36.7 percent of the dried transparent PLA polylactic acid copolymer with the melt index of 10-20, 10 percent of levorotatory polylactic acid, 20 percent of the dried starch master batches, 30 percent of 10000 meshes of talcum powder, 1.5 percent of chain extender, 0.3 percent of KH550 coupling agent, 0 percent of PBAT toughening agent, 0.4 percent of nucleating agent, 0.5 percent of compound antioxidant and 1 percent of processing aid are mixed in a high-speed mixer, so that all the components are fully stirred and uniformly dispersed.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
Comparative example 2
The starch/polylactic acid/PBAT nanocomposite material and the preparation method thereof comprise S1, wherein, polylactic acid and starch master batches are dried for 3-5 hours at 80 ℃, 41.3 percent of the dried transparent PLA polylactic acid copolymer with the melt index of 10-20, 0 percent of levorotatory polylactic acid, 20 percent of the dried starch master batches, 30 percent of 10000 meshes of talcum powder, 1.5 percent of chain extender, 0.3 percent of KH550 coupling agent, 5 percent of PBAT toughening agent, 0.4 percent of nucleating agent, 0.5 percent of compound antioxidant and 1 percent of processing aid are mixed in a high-speed mixer, so that all components are fully stirred and uniformly dispersed.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
Comparative example 3
The starch/polylactic acid/PBAT nano composite material and the preparation method thereof comprise S1, drying polylactic acid and starch master batches at 80 ℃ for 3-5 hours, mixing 71.3% of dried transparent PLA polylactic acid copolymer with the melt index of 10-20, 0% of L-polylactic acid, 20% of dried starch master batches, 0% of 10000 meshes of talcum powder, 1.5% of chain extender, 0.3% of KH550 coupling agent, 5% of PBAT toughening agent, 0.4% of nucleating agent, 0.5% of compound antioxidant and 1% of processing aid in a high-speed mixer, and fully stirring and uniformly dispersing all the components.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
Comparative example 4
The starch/polylactic acid/PBAT nano composite material and the preparation method thereof of the comparative example are characterized in that S1, polylactic acid and starch master batches are dried for 3-5 hours at the temperature of 80 ℃, 61.2% of dried transparent PLA polylactic acid copolymer with the melt index of 10-20, 10% of levorotatory polylactic acid, 20% of dried starch master batches, 0% of 10000 meshes of talcum powder, 2% of chain extender, 0.3% of KH550 coupling agent, 5% of PBAT toughening agent, 0% of nucleating agent, 0.5% of compound antioxidant and 1% of processing aid are mixed in a high-speed mixer, and all the components are fully stirred and uniformly dispersed.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
In summary, the experimental data of examples 1 to 8 and comparative examples 1 to 4 are combined together and, in weight percent, the following table one is obtained:
TABLE 1 ingredient Table of starch/polylactic acid/PBAT nanocomposites prepared in examples and comparative examples
For the experiments of examples 1-8 and comparative examples 1-4, the performance test criteria and the data obtained are shown in Table 2 below:
TABLE 2 starch/polylactic acid/PBAT nanocomposites prepared in the examples and comparative examples
As can be seen from the data in tables 1 and 2, in comparison with comparative example 1, in the absence of the toughening agent in the raw material formulation of comparative example 1, the material obtained in comparative example 1 has lower expansion/contraction ratio at break and lower notched impact strength than those of the raw materials obtained in examples 1 to 8, and in the melt index, the material obtained in other examples has a melt index higher than that of comparative example 1 except that the material obtained in examples 3 and 7 has a melt index lower than that of comparative example 1; in contrast to comparative example 2, in the case of comparative example 2 lacking PLLA/PDLA and having 10000 mesh talc and nucleating agent, the tensile strength of the material prepared in comparative example 2 was higher than that of comparative example 2 in the tensile strength comparison, except that the tensile strength of the material of example 1 was lower than that of comparative example 2, and the tensile strengths of the materials of other examples 2-8 were all higher than that of comparative example 2; in the raw material ratio of the comparative example 3, PLLA/PDLA and 10000 meshes of talcum powder are simultaneously lacked, and in the presence of a nucleating agent, the proportion of the PLA copolymer is higher, the tensile strength of the obtained material is obviously higher than that of the comparative example 3 except for the tensile strength of the example 1, the tensile strength of the materials of the other examples 2-8 is obviously higher than that of the comparative example 3, the elongation at break and the melt index of the comparative example 3 are both larger than those of the examples 1-8, the notched impact strength of the materials of the other examples except for the example 6 is smaller than that of the comparative example 3, and the heat distortion temperature HDT, the flexural modulus and the flexural strength of the material of the comparative example 3 are all smaller than those of the data of the examples 1-8; the composition ratio in comparative example 4 is less than 10000 meshes of talcum powder, the elongation at break, the notch impact strength and the melt index of the material obtained in comparative example 4 are all larger than those of examples 1-8 except that the tensile strength is similar to those of examples 1-8, and the heat distortion temperature HDT, the flexural modulus and the flexural strength of the material obtained in comparative example 4 are all smaller than those of examples 1-8 in other properties.
From the results analysis, it can be seen that when PLLA/PDLA is used, it can be used in place of nucleating agent, and can obtain obviously excellent thermal deformation temperature HDT, flexural modulus and flexural strength under the action of 10000 mesh talc powder, especially in examples 5 and 6, the obtained mechanical properties of melt index, notch impact strength, elongation at break and tensile strength are all excellent, in addition, the obtained product has good high temperature resistance, can effectively improve the mechanical properties of the material, improve the processability thereof, make the material more easily machine-shaped, can directly improve the production efficiency, reduce the production difficulty, and use the prepared homopolymerized levorotatory PLA as nucleating agent, and use the commercially available levorotatory and dextrorotatory copolymerized PLA as base material, and can avoid poor compatibility of the material.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (10)
1. A starch/polylactic acid/PBAT nanocomposite is characterized in that: the weight percentages of the raw materials are as follows: 20-40% of polylactic acid copolymer, 5-25% of levorotatory polylactic acid, 10-20% of starch master batch, 20-40% of talcum powder, 1-2% of chain extender, 0.2-0.4% of coupling agent, 4-6% of flexibilizer, 0.2-0.5% of nucleating agent, 0.2-0.6% of compound antioxidant and 0.5-1% of processing aid.
2. The starch/polylactic acid/PBAT nanocomposite material of claim 1, wherein: the fineness of the talcum powder is 10000-15000 meshes.
3. The starch/polylactic acid/PBAT nanocomposite material of claim 1, wherein: the starch master batch is prepared from 70-85% of starch by weight through low-temperature processing by an internal mixer, and the preparation method comprises the following steps:
s1, uniformly mixing 70-85% of starch, 10-20% of food-grade glycerol and 5-10% of food-grade silicone oil, putting into an internal mixer, controlling the temperature at 90-110 ℃, and uniformly mixing to form a viscous-state solid.
S2, transferring the viscous state solid into a double-wrist granulator by weighing and heating, extruding, air cooling, and granulating at 90-110 ℃.
4. The starch/polylactic acid/PBAT nanocomposite material of claim 1, wherein: the toughening agent is a polybutylene adipate-terephthalate copolymer.
5. The starch/polylactic acid/PBAT nanocomposite material of claim 1, wherein: the nucleating agent is a mixture of sebacic acid and diphenyl dihydrazide, and the processing aid is hyperbranched resin or silicone.
6. The starch/polylactic acid/PBAT nanocomposite material of claim 1, wherein: the preparation method of the levorotatory polylactic acid comprises the following steps: s1, lactide synthesis; s2, purifying; s3, polymerization of L-PLA.
7. The starch/polylactic acid/PBAT nanocomposite material of claim 6, wherein: in the lactide synthesis: adding lactic acid into a three-neck flask, slowly heating to 110 ℃ under the protection of nitrogen atmosphere, dehydrating under normal pressure, heating to 140-160 ℃, adding a stannous octoate catalyst for reaction, removing water generated in the polycondensation reaction, quickly heating, continuously increasing the vacuum degree, and cracking the oligomer to generate lactide.
8. The starch/polylactic acid/PBAT nanocomposite material of claim 6, wherein: the specific purification operation comprises the steps of hydrolyzing lactide, recrystallizing, filtering after crystallization is complete, drying in vacuum at 45 ℃ to constant mass, wherein the recrystallization time is 3-4 times, and the yield is 70-80%. The obtained lactide is stored in vacuum at low temperature.
9. The starch/polylactic acid/PBAT nanocomposite material of claim 6, wherein: the polymerization step of the L-PLA is to use lactide as a monomer and stannous octoate as a catalyst, prepare a polylactic acid prepolymer through lactide ring-opening polymerization, and use protonic acid as a catalyst to polymerize the lactide into PLLA through ring-opening polymerization at 40-60 ℃.
10. A method for preparing a starch/polylactic acid/PBAT nanocomposite according to any one of claims 1 to 9, wherein: the method specifically comprises the following steps:
s1, drying the polylactic acid and the starch masterbatch for 3-5 hours at 80 ℃, mixing the dried polylactic acid, the dried starch masterbatch, the levorotatory polylactic acid, the talcum powder, the chain extender, the coupling agent, the flexibilizer, the nucleating agent, the compound antioxidant and the processing aid in a high-speed mixer, and fully stirring and uniformly dispersing all the components.
S2, adding the mixed materials into a double-screw extruder for melt extrusion, wherein the melt extrusion temperature is 260-300 ℃, the screw rotation speed is 300-500 r/m, and the glass fiber side feed is added.
And S3, cooling, air-drying, granulating, strongly magnetizing and packaging the extruded material to obtain a finished product.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114085508A (en) * | 2021-11-17 | 2022-02-25 | 河北旭阳能源有限公司 | Preparation method of temperature-resistant straw |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102863654A (en) * | 2012-10-11 | 2013-01-09 | 武汉华丽环保科技有限公司 | Starch and polylactic acid composite material and preparation method thereof |
| CN103421285A (en) * | 2013-07-08 | 2013-12-04 | 常州大学 | Environment-friendly heat-resistant polylactic acid and preparation method thereof |
| CN106349667A (en) * | 2016-08-31 | 2017-01-25 | 深圳市虹彩新材料科技有限公司 | High strength and high heat resistance polylactic acid composite material and preparation method thereof |
| CN110845830A (en) * | 2019-11-13 | 2020-02-28 | 青岛润兴塑料新材料有限公司 | Starch filled PLA/PBAT full-biodegradable composite material and preparation method thereof |
-
2020
- 2020-12-31 CN CN202011633860.0A patent/CN113429762A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102863654A (en) * | 2012-10-11 | 2013-01-09 | 武汉华丽环保科技有限公司 | Starch and polylactic acid composite material and preparation method thereof |
| CN103421285A (en) * | 2013-07-08 | 2013-12-04 | 常州大学 | Environment-friendly heat-resistant polylactic acid and preparation method thereof |
| CN106349667A (en) * | 2016-08-31 | 2017-01-25 | 深圳市虹彩新材料科技有限公司 | High strength and high heat resistance polylactic acid composite material and preparation method thereof |
| CN110845830A (en) * | 2019-11-13 | 2020-02-28 | 青岛润兴塑料新材料有限公司 | Starch filled PLA/PBAT full-biodegradable composite material and preparation method thereof |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114085508A (en) * | 2021-11-17 | 2022-02-25 | 河北旭阳能源有限公司 | Preparation method of temperature-resistant straw |
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