CN114437458A - Preparation method of biodegradable starch-based polypropylene plastic sheet - Google Patents
Preparation method of biodegradable starch-based polypropylene plastic sheet Download PDFInfo
- Publication number
- CN114437458A CN114437458A CN202210214528.3A CN202210214528A CN114437458A CN 114437458 A CN114437458 A CN 114437458A CN 202210214528 A CN202210214528 A CN 202210214528A CN 114437458 A CN114437458 A CN 114437458A
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- starch
- plastic sheet
- polypropylene plastic
- coupling agent
- based polypropylene
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- 229920002472 Starch Polymers 0.000 title claims abstract description 61
- 239000008107 starch Substances 0.000 title claims abstract description 61
- 235000019698 starch Nutrition 0.000 title claims abstract description 61
- -1 polypropylene Polymers 0.000 title claims abstract description 44
- 239000004743 Polypropylene Substances 0.000 title claims abstract description 40
- 229920001155 polypropylene Polymers 0.000 title claims abstract description 40
- 239000002985 plastic film Substances 0.000 title claims abstract description 28
- 238000002360 preparation method Methods 0.000 title claims abstract description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 29
- 239000000463 material Substances 0.000 claims abstract description 22
- 238000002156 mixing Methods 0.000 claims abstract description 21
- 239000000956 alloy Substances 0.000 claims abstract description 19
- 239000007822 coupling agent Substances 0.000 claims abstract description 17
- 239000004033 plastic Substances 0.000 claims abstract description 11
- 229920003023 plastic Polymers 0.000 claims abstract description 11
- 229920002261 Corn starch Polymers 0.000 claims abstract description 8
- 239000008120 corn starch Substances 0.000 claims abstract description 8
- 238000001816 cooling Methods 0.000 claims abstract description 7
- 239000000314 lubricant Substances 0.000 claims abstract description 7
- 238000009966 trimming Methods 0.000 claims abstract description 7
- 239000002270 dispersing agent Substances 0.000 claims abstract description 5
- 238000001035 drying Methods 0.000 claims abstract description 5
- 238000002844 melting Methods 0.000 claims abstract description 3
- 230000008018 melting Effects 0.000 claims abstract description 3
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 claims description 8
- 150000004645 aluminates Chemical class 0.000 claims description 7
- 235000021355 Stearic acid Nutrition 0.000 claims description 6
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 claims description 6
- 239000008117 stearic acid Substances 0.000 claims description 6
- 239000006087 Silane Coupling Agent Substances 0.000 claims description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 3
- 238000009740 moulding (composite fabrication) Methods 0.000 claims description 2
- 238000006065 biodegradation reaction Methods 0.000 abstract description 2
- 230000000694 effects Effects 0.000 abstract description 2
- 238000010438 heat treatment Methods 0.000 description 8
- 229910045601 alloy Inorganic materials 0.000 description 5
- 239000004698 Polyethylene Substances 0.000 description 4
- 229920000573 polyethylene Polymers 0.000 description 4
- 238000010008 shearing Methods 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 3
- 238000002474 experimental method Methods 0.000 description 3
- 239000003208 petroleum Substances 0.000 description 3
- 230000007613 environmental effect Effects 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 230000004075 alteration Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
- C08J5/18—Manufacture of films or sheets
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2303/00—Characterised by the use of starch, amylose or amylopectin or of their derivatives or degradation products
- C08J2303/02—Starch; Degradation products thereof, e.g. dextrin
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2323/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
- C08J2323/02—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers not modified by chemical after treatment
- C08J2323/10—Homopolymers or copolymers of propene
- C08J2323/12—Polypropene
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2403/00—Characterised by the use of starch, amylose or amylopectin or of their derivatives or degradation products
- C08J2403/02—Starch; Degradation products thereof, e.g. dextrin
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/04—Oxygen-containing compounds
- C08K5/09—Carboxylic acids; Metal salts thereof; Anhydrides thereof
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/04—Oxygen-containing compounds
- C08K5/10—Esters; Ether-esters
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
Abstract
The invention discloses a preparation method of a biodegradable starch-based polypropylene plastic sheet, which comprises the following steps: drying the corn starch until the water content is lower than 4% to obtain low-water starch; adding a coupling agent, a dispersing agent, a lubricating agent and polypropylene plastic into the low-moisture starch, and uniformly mixing to obtain a mixed material; melting and mixing the mixed materials at the temperature of 150-190 ℃ to obtain an alloy material; cooling, tabletting and forming, trimming and coiling the alloy material to obtain a starch-based polypropylene plastic sheet; in the starch-based polypropylene plastic sheet, the water content of starch is low, so that the condition of bubbles is reduced, and the mechanical property of the material is improved; the content of starch in the plastic sheet is increased, and the biodegradation effect is better.
Description
Technical Field
The invention relates to the technical field of high molecular substance material products, in particular to a preparation method of a biodegradable starch-based polypropylene plastic sheet.
Background
With the increasing environmental requirements and the implementation of environmental policies, the application of petroleum-based plastics in the field of disposable plastic products is increasingly restricted due to the increasing price of raw materials and the increasing requirements for the degradation of plastic products. Starch is widely used in plastic products as a natural, renewable, biodegradable raw material.
Starch is a polar high molecular material, so that the water content of the starch is relatively high (about 13-14%), while polypropylene is a non-polar high molecular material and belongs to a hydrophobic material; when the starch and the petroleum-based polypropylene are mixed and melted, the performance of the polypropylene body can be greatly damaged by moisture in the starch, and the compatibility of the polypropylene body and the petroleum-based polypropylene is influenced, so that the adding amount of the starch in the prior art is generally not more than 25%, and alloy products obtained by the process have a plurality of defects: such as bubbles in the alloy, uneven starch distribution, poor mechanical properties of the alloy, very brittle materials, etc.
Disclosure of Invention
The invention aims to provide a preparation method of a biodegradable starch-based polypropylene plastic sheet, so as to solve the problems in the background technology. In order to achieve the purpose, the invention provides the following technical scheme:
a preparation method of a biodegradable starch-based polypropylene plastic sheet comprises the following steps:
(a) drying the corn starch until the water content is lower than 4% to obtain low-water starch;
(b) adding a coupling agent, a dispersing agent, a lubricating agent and polypropylene plastic into the low-moisture starch, and uniformly mixing to obtain a mixed material;
(c) melting and mixing the mixed materials at the temperature of 150-190 ℃ to obtain an alloy material;
(d) and tabletting, forming, trimming, cooling and coiling the alloy material to obtain the starch-based polypropylene plastic sheet.
Further, in the step (a), the drying is carried out in a high-speed mixer, and the rotating speed of the high-speed mixer is 750-1500 r/min.
Further, in the step (b), the weight proportions of the low-water starch, the coupling agent, the dispersing agent and the lubricating agent are respectively 25-70%, 0-3%, 1-5% and 1-3%.
Further, in the step (b), the coupling agent is selected from any one of a silane coupling agent, a titanate coupling agent, an aluminate coupling agent, or a combination of at least two thereof.
Further, in the step (b), the lubricant may be stearic acid or stearate.
Further, in the step (c), the melt mixing is performed in a twin-screw extruder.
The invention has the beneficial effects that: in the starch-based polypropylene plastic sheet, the water content of starch is low, so that the condition of bubbles is reduced, and the mechanical property of the material is improved; the content of starch in the plastic sheet is increased, and the biodegradation effect is better.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the 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 first embodiment is as follows:
adding corn starch into a high-speed mixer, setting the rotating speed to be 750r/min, and stirring for 50 minutes to obtain low-water starch with the water content of about 3.75 percent;
adding 25kg of low-water starch, 1.5kg of aluminate coupling agent, 2kg of polyethylene wax, 0.5kg of stearic acid and 75kg of polypropylene plastic into mixing equipment, and uniformly mixing to obtain a mixed material;
uniformly adding the mixed material into a double-screw extruder, and carrying out melt mixing to obtain an alloy material, wherein the extruder is provided with six heating zones, and the heating temperatures are respectively 90 ℃, 160 ℃ and 175 ℃;
and extruding the alloy material from a die orifice of an extruder, tabletting and forming by a three-roller calender, trimming by a shearing device, conveying and cooling by a conveying device, and finally coiling by a coiling device to obtain the starch-based polypropylene plastic sheet.
Example two:
adding corn starch into a high-speed mixer, setting the rotating speed to be 1500r/min, and stirring for 30 minutes to obtain low-water starch with the water content of about 3.18 percent;
adding 30kg of low-water starch, 1.5kg of aluminate coupling agent, 3kg of polyethylene wax, 1kg of stearic acid and 70kg of polypropylene plastic into mixing equipment, and uniformly mixing to obtain a mixed material;
uniformly adding the mixed material into a double-screw extruder, and carrying out melt mixing to obtain an alloy material, wherein the extruder is provided with six heating zones, and the heating temperatures are respectively 90 ℃, 160 ℃ and 175 ℃;
and extruding the alloy material from a die orifice of an extruder, tabletting and forming by a three-roller calender, trimming by a shearing device, conveying and cooling by a conveying device, and finally coiling by a coiling device to obtain the starch-based polypropylene plastic sheet.
Example three:
adding corn starch into a high-speed mixer, setting the rotating speed to be 750r/min, and stirring for 120 minutes to obtain low-water starch with the water content of about 3.32%;
adding 40kg of low-water starch, 2kg of aluminate coupling agent, 3kg of polyethylene wax, 1kg of stearic acid and 60kg of polypropylene plastic into mixing equipment, and uniformly mixing to obtain a mixed material;
uniformly adding the mixed material into a double-screw extruder, and carrying out melt mixing to obtain an alloy material, wherein the extruder is provided with six heating zones, and the heating temperatures are respectively 90 ℃, 160 ℃ and 175 ℃;
and extruding the alloy material from a die orifice of an extruder, tabletting and forming by a three-roller calender, trimming by a shearing device, conveying and cooling by a conveying device, and finally coiling by a coiling device to obtain the starch-based polypropylene plastic sheet.
Example four:
adding corn starch into a high-speed mixer, setting the rotating speed to be 1500r/min, and stirring for 30 minutes to obtain low-water starch with the water content of about 3.18 percent;
adding 50kg of low-water starch, 1kg of aluminate coupling agent, 2kg of polyethylene wax, 1kg of stearic acid and 50kg of polypropylene plastic into mixing equipment, and uniformly mixing to obtain a mixed material;
uniformly adding the mixed material into a double-screw extruder, and carrying out melt mixing to obtain an alloy material, wherein the extruder is provided with six heating zones, and the heating temperatures are respectively 90 ℃, 160 ℃ and 175 ℃;
and extruding the alloy material from a die orifice of an extruder, tabletting and forming by a three-roller calender, trimming by a shearing device, conveying and cooling by a conveying device, and finally coiling by a coiling device to obtain the starch-based polypropylene plastic sheet.
In order to verify the beneficial effect of the starch-based polypropylene plastic sheet obtained by the preparation method, two experiments are used for verifying the beneficial effect;
experiment one:
in order to verify the influence of the water content of the starch on the mechanical property test of the prepared starch-based polypropylene plastic sheet, the plastic sheet prepared by respectively mixing the same amount of low-water starch (water content of 3%) and common corn starch (water content of 13%) with polypropylene is compared, and the mechanical property test results are shown in the following table:
table one:
as can be seen from Table I, the mechanical properties of the alloy formed by low-moisture starch and polypropylene are obviously better than those of the alloy formed by ordinary starch and polypropylene.
Experiment two:
in order to verify the influence of different amounts of low-moisture starch on the mechanical property test of the prepared starch-based polypropylene plastic sheet, a plurality of groups of low-moisture starch (with a water content of 3%) with different amounts are respectively mixed with polypropylene to prepare the plastic sheet, and the mechanical property test results are compared and shown in the following table:
table two:
| low water starch content (%) | 25 | 27 | 30 | 35 | 37 | 40 | 43 | 45 | 50 | 55 | 60 | 65 | 70 |
| Tensile Strength (MPa) | 21 | 20 | 18 | 17 | 16 | 16 | 15 | 15 | 12 | 9 | 8 | 7 | 6 |
| Elongation at Break (%) | 25 | 23 | 21 | 19 | 17 | 17 | 16 | 16 | 10 | 7 | 6 | 5 | 4 |
As can be seen from the table II, when the addition amount of the low-moisture starch is 50%, the mechanical property of the low-moisture starch is equivalent to that of the common starch with the addition amount of 30%; and when the addition amount reaches 70%, the material still has good mechanical properties.
Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (6)
1. A preparation method of a biodegradable starch-based polypropylene plastic sheet is characterized by comprising the following steps:
(a) drying the corn starch until the water content is lower than 4% to obtain low-water starch;
(b) adding a coupling agent, a dispersing agent, a lubricating agent and polypropylene plastic into the low-moisture starch, and uniformly mixing to obtain a mixed material;
(c) melting and mixing the mixed materials at the temperature of 150-190 ℃ to obtain an alloy material;
(d) and tabletting, forming, trimming, cooling and coiling the alloy material to obtain the starch-based polypropylene plastic sheet.
2. The starch-based polypropylene plastic sheet according to claim 1, wherein: in the step (a), the drying is carried out in a high-speed mixer, and the rotating speed of the high-speed mixer is 750-1500 r/min.
3. The starch-based polypropylene plastic sheet according to claim 1, wherein: in the step (b), the weight proportions of the low-water starch, the coupling agent, the dispersing agent and the lubricating agent are respectively 25-70%, 0-3%, 1-5% and 1-3%.
4. The starch-based polypropylene plastic sheet according to claim 1, wherein: in the step (b), the coupling agent is selected from any one of silane coupling agent, titanate coupling agent and aluminate coupling agent or the combination of at least two of the silane coupling agent, the titanate coupling agent and the aluminate coupling agent.
5. The starch-based polypropylene plastic sheet according to claim 1, wherein: in the step (b), the lubricant may be stearic acid or stearate.
6. The starch-based polypropylene plastic sheet according to claim 1, wherein: in said step (c), said melt mixing is carried out in a twin screw extruder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210214528.3A CN114437458A (en) | 2022-03-04 | 2022-03-04 | Preparation method of biodegradable starch-based polypropylene plastic sheet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210214528.3A CN114437458A (en) | 2022-03-04 | 2022-03-04 | Preparation method of biodegradable starch-based polypropylene plastic sheet |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114437458A true CN114437458A (en) | 2022-05-06 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210214528.3A Pending CN114437458A (en) | 2022-03-04 | 2022-03-04 | Preparation method of biodegradable starch-based polypropylene plastic sheet |
Country Status (1)
| Country | Link |
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| CN (1) | CN114437458A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101270206A (en) * | 2008-05-20 | 2008-09-24 | 安徽德琳环保发展（集团）有限公司 | Biodegradation plastics with high-content of starch for producing tableware and method of producing the same |
| CN101698709A (en) * | 2009-10-28 | 2010-04-28 | 苏州禾盛新型材料股份有限公司 | Polypropylene modified material for degradable disposable tableware and preparation method thereof |
| CN107266782A (en) * | 2016-04-06 | 2017-10-20 | 黑龙江鑫达企业集团有限公司 | A kind of starch-based degradable biological plastics PP and preparation method thereof |
| CN111849036A (en) * | 2020-07-21 | 2020-10-30 | 成都新柯力化工科技有限公司 | Water-resistant biological starch plastic and preparation method thereof |
| CN113001808A (en) * | 2021-02-18 | 2021-06-22 | 董丹丹 | Preparation process of degradable polypropylene plastic |
-
2022
- 2022-03-04 CN CN202210214528.3A patent/CN114437458A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101270206A (en) * | 2008-05-20 | 2008-09-24 | 安徽德琳环保发展（集团）有限公司 | Biodegradation plastics with high-content of starch for producing tableware and method of producing the same |
| CN101698709A (en) * | 2009-10-28 | 2010-04-28 | 苏州禾盛新型材料股份有限公司 | Polypropylene modified material for degradable disposable tableware and preparation method thereof |
| CN107266782A (en) * | 2016-04-06 | 2017-10-20 | 黑龙江鑫达企业集团有限公司 | A kind of starch-based degradable biological plastics PP and preparation method thereof |
| CN111849036A (en) * | 2020-07-21 | 2020-10-30 | 成都新柯力化工科技有限公司 | Water-resistant biological starch plastic and preparation method thereof |
| CN113001808A (en) * | 2021-02-18 | 2021-06-22 | 董丹丹 | Preparation process of degradable polypropylene plastic |
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Application publication date: 20220506 |