CN112920439A - Degradable plastic film made of whole corn flour and preparation method of degradable plastic film - Google Patents
Degradable plastic film made of whole corn flour and preparation method of degradable plastic film Download PDFInfo
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- CN112920439A CN112920439A CN202110117869.4A CN202110117869A CN112920439A CN 112920439 A CN112920439 A CN 112920439A CN 202110117869 A CN202110117869 A CN 202110117869A CN 112920439 A CN112920439 A CN 112920439A
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- 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
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- 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
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- 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
- C08J2329/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an alcohol, ether, aldehydo, ketonic, acetal, or ketal radical; Hydrolysed polymers of esters of unsaturated alcohols with saturated carboxylic acids; Derivatives of such polymer
- C08J2329/02—Homopolymers or copolymers of unsaturated alcohols
- C08J2329/04—Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids
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- 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
- C08J2401/00—Characterised by the use of cellulose, modified cellulose or cellulose derivatives
- C08J2401/08—Cellulose derivatives
- C08J2401/26—Cellulose ethers
- C08J2401/28—Alkyl ethers
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- 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
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- 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
- C08J2429/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an alcohol, ether, aldehydo, ketonic, acetal, or ketal radical; Hydrolysed polymers of esters of unsaturated alcohols with saturated carboxylic acids; Derivatives of such polymer
- C08J2429/02—Homopolymers or copolymers of unsaturated alcohols
- C08J2429/04—Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids
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- 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
- C08K5/16—Nitrogen-containing compounds
- C08K5/21—Urea; Derivatives thereof, e.g. biuret
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- 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
- C08K5/36—Sulfur-, selenium-, or tellurium-containing compounds
- C08K5/43—Compounds containing sulfur bound to nitrogen
- C08K5/435—Sulfonamides
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- 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
- C08K5/49—Phosphorus-containing compounds
- C08K5/51—Phosphorus bound to oxygen
- C08K5/52—Phosphorus bound to oxygen only
- C08K5/521—Esters of phosphoric acids, e.g. of H3PO4
- C08K5/523—Esters of phosphoric acids, e.g. of H3PO4 with hydroxyaryl compounds
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Abstract
The invention relates to a corn whole powder degradable plastic film and a preparation method thereof. The degradable film comprises the following components: 30-70 parts of corn flour, 40-65 parts of polyvinyl alcohol, 15-30 parts of carboxymethyl cellulose, 8-20 parts of ionic liquid plasticizer, 2-6 parts of urea and 3-8 parts of resorcinol bis (diphenyl phosphate). The cation of the ionic liquid plasticizer isOne end of the difunctional imidazole cation contains a hydroxyl structure, and the other end of the difunctional imidazole cation is an ester-functionalized long-chain structure; NTf with hydrophobic anion2An anion. The water absorption of the degradable plastic film prepared by the invention is greatly reduced, which shows that the water resistance of the degradable plastic film is better; the mechanical property is better, the flame retardant effect is good, and the preparation method is simple.
Description
Technical Field
The invention belongs to the technical field of degradable plastics, and particularly relates to a preparation method of a corn whole powder degradable plastic film.
Background
Since the 21 st century, the global environment is protected, a resource circulation type society is constructed, and a sustainable development road is a world focus and urgent task. Currently, plastic products are lightweight, waterproof, and corrosion resistantExcellent performances such as corrosion and high strength are favored by people, and the paint is widely applied to various fields of production and life of people. However, the large amount of waste plastic products brings about the trouble of "white pollution" because of their non-degradability. For this reason, research and development on degradable plastics have been carried out since the 70 s. Starch as a natural high molecular compound has wide sources, various varieties and low cost, can be completely degraded in various natural environments, and is finally decomposed into CO2And H2O, no pollution to the environment, so the starch-based degradable plastics become a type of biodegradable plastics which are researched and developed most at home and abroad.
The starch-based biodegradable plastic is generally prepared by blending starch, a plasticizer and degradable resin, such as polylactic acid, polycaprolactone, polybutylene succinate and the like, and has better processing performance and cost advantage compared with pure degradable resin. Wherein the main components of the biodegradable plastic film prepared by taking corn starch as a main raw material comprise cellulose, hemicellulose and a small amount of protein, fat and starch; the plastic film has low production cost and simple production process flow, and is mainly used for industrial antistatic product packaging, pesticide and fertilizer small packaging, living goods packaging, garbage packaging and the like. Therefore, the reasonable utilization of natural resources can be optimized based on the research and development of the corn whole powder biodegradable plastic, the dependence on petroleum resources is reduced, and the problem of white pollution can be solved to a certain extent. However, the existing corn starch-based degradable plastic film still has the problems of low mechanical property, high water absorption rate and the like, and needs to be solved.
Disclosure of Invention
In order to solve the defects of the prior art, the invention provides a preparation method of a corn full-starch degradable plastic film, which comprises the following specific scheme:
a corn whole meal degradable plastic film, which comprises the following components: 30-70 parts of corn flour, 40-65 parts of polyvinyl alcohol, 15-30 parts of carboxymethyl cellulose, 8-20 parts of ionic liquid plasticizer, 2-6 parts of urea and 3-8 parts of resorcinol bis (diphenyl phosphate).
The ionic liquid plasticizer has the following structure,
the positive ions of the plasticizer are difunctional imidazole positive ions, one end of the difunctional imidazole positive ions contains a hydroxyl structure, and the other end of the difunctional imidazole positive ions is an ester group functionalized long-chain structure; the side chain with functionalized hydroxyl can generate hydrogen bond interaction with the hydroxyl in the full starch and the polyvinyl alcohol, and the long ester-based side chain at the other end can be embedded into the gap between the polyvinyl alcohol and the carboxymethyl cellulose to play the roles of toughening and plasticizing. The anion of the ionic liquid plasticizer also contains bis (trifluoromethanesulfonyl) imide anion (NTF)2) On one hand, the anion is bound around the cation through electrostatic interaction and is embedded in the gaps of the crosslinking network to play a toughening role; bis (trifluoromethanesulfonylimide) anion (NTF) on the other hand2) The hydrophobic ions are uniformly dispersed in the system, and the water resistance of the film can be effectively improved.
The resorcinol bis (diphenyl phosphate) is an organic phosphorus flame retardant, and the flame retardant property of the film can be effectively improved by adding a small amount of resorcinol bis (diphenyl phosphate).
The preparation process of the degradable plastic film mainly comprises the following steps:
(1) gelatinization of corn full starch: putting a certain amount of whole corn flour into a three-necked bottle, adding deionized water, stirring uniformly to fully swell the whole corn flour, then adding polyvinyl alcohol and urea into the three-necked bottle according to the mass ratio, mixing with the whole corn flour after dissolving, stirring and heating to 90 ℃, and carrying out heat preservation reaction for 30-40min to gelatinize the corn starch.
(2) Mixing materials: sequentially adding a certain amount of the methyl cellulose, the ionic liquid plasticizer and the flame retardant into the gelatinized corn starch according to the mass ratio, and violently stirring and blending for 2 hours at the temperature of 80-90 ℃;
(3) molding: pouring the blending liquid prepared in the step 2 on a horizontal glass plate for tape casting, and uncovering the film after air drying to prepare the degradable plastic film.
The invention has the advantages that the water resistance of the degradable plastic film prepared by adopting the hydrophobic bifunctional ionic liquid as the plasticizer is greatly improved; the mechanical property is better, the flame retardant effect is good, and the preparation method is simple.
Detailed Description
The present invention is further described below with reference to examples, which are only some examples of the present invention. Based on the embodiments of the present invention, those skilled in the art can make equivalent substitutions or improvements without making creative efforts and are within the protection scope of the present invention.
Preparation of ionic liquid plasticizer
The plasticizer used in the invention is self-made in a laboratory, and the specific reaction route is as follows:
the synthesis of the ionic liquid plasticizer mainly comprises two steps of reactions, and specific preparation examples are as follows:
(1) mixing hydroxyethyl imidazole (1120g,10mol) and ethyl 6-bromohexanoate (2220g,10mol) in a methanol solvent, carrying out reflux reaction for 48h, evaporating the solvent after the reaction is finished, washing the obtained viscous yellow liquid for 5 times by using tetrahydrofuran (1000mL), and draining the solvent to obtain 2840g of hydroxyl and ester group modified bifunctional bromine salt;
(2) adding the bromine salt (223g, 0.5mol) prepared in the step 1 and lithium bistrifluoromethanesulfonylimide (143.5g, 0.5mol) into a reaction kettle in sequence, stirring for reaction for 5 hours, separating the reaction into two phases, washing the oil phase with 300mL of deionized water for 3 times after liquid separation, and drying in vacuum to obtain a light yellow viscous liquid, namely the imidazole difunctional NTF2An ionic liquid plasticizer.
The plasticizer prepared above was analyzed by nuclear magnetism, and the specific results were as follows:1H NMR(600MHz,DMSO)δ＝1.07(CH3)；1.29-2.32(4×CH2)；3.63(CH2)；4.01(CH2)4.35(CH2)；4.96(OH)；5.01(CH2)；7.75(CH)；7.92(CH)；8.92(CH)ppm；13C NMR(600MHz,DMSO)δ＝14.1(CH3)；24.7(CH2)；27.0(CH2)；29.8(CH2)；34.0(CH2)；53.0(CH2)；54.5(CH2)；60(CH2)；122-123(2×CH)；137(CH)；149(2×CF3)。
preparation of degradable plastic film
Example 1
The embodiment provides a corn whole meal degradable plastic film and a preparation method thereof, and the degradable film comprises the following components: 35 parts of corn flour, 48 parts of polyvinyl alcohol, 16 parts of carboxymethyl cellulose, 8 parts of ionic liquid plasticizer, 3 parts of urea and 3 parts of resorcinol bis (diphenyl phosphate).
The preparation process of the degradable plastic film mainly comprises the following steps:
(1) gelatinization of corn full starch: placing 35g of whole corn flour into a three-necked bottle, adding 700mL of deionized water, uniformly stirring to fully swell the whole corn flour, then adding 48g of polyvinyl alcohol and 3g of urea into 500mL of deionized water according to the mass ratio, stirring, dissolving, mixing with the whole corn flour, stirring, heating to 90 ℃, and carrying out heat preservation reaction for 35min to gelatinize the corn starch.
(2) Mixing materials: sequentially adding 16g of carboxymethyl cellulose, 8g of ionic liquid plasticizer and 3g of resorcinol bis (diphenyl phosphate) into gelatinized corn starch according to the mass ratio, and violently stirring and blending for 2 hours at the temperature of 80-90 ℃;
(3) molding: pouring the blending liquid prepared in the step 2 on a horizontal glass plate for tape casting, and uncovering the film after air drying to prepare the degradable plastic film.
Example 2
The embodiment provides a corn whole meal degradable plastic film and a preparation method thereof, and the degradable film comprises the following components: 45 parts of corn flour, 50 parts of polyvinyl alcohol, 26 parts of carboxymethyl cellulose, 13 parts of ionic liquid plasticizer, 4 parts of urea and 5 parts of resorcinol bis (diphenyl phosphate).
The preparation method of the degradable corn whole flour plastic film is the same as that in example 1, and all the components are replaced by the same amount.
Example 3
The embodiment provides a corn whole meal degradable plastic film and a preparation method thereof, and the degradable film comprises the following components: 68 parts of corn flour, 65 parts of polyvinyl alcohol, 30 parts of carboxymethyl cellulose, 20 parts of an ionic liquid plasticizer, 6 parts of urea and 8 parts of resorcinol bis (diphenyl phosphate).
The preparation method of the degradable corn whole flour plastic film is the same as that in example 1, and all the components are replaced by the same amount.
Comparative example
The plasticizer used in this comparative example was glycerol, which comprised the following major components: 30 parts of corn whole powder, 20 parts of polyvinyl alcohol, 8 parts of urea, 6 parts of glycerol and 16 parts of formaldehyde;
the preparation process comprises the following steps:
adding 30g of whole corn flour, 20g of polyvinyl alcohol and 8g of urea into 1000mL of deionized water in sequence, uniformly mixing, gelatinizing at 90 ℃, adding 16g of formaldehyde and 6g of glycerol, reacting at 90 ℃ for 2 hours in a heat preservation manner, pouring the mixed solution on a preheated glass plate while the mixed solution is hot, casting to prepare a membrane, drying and demoulding to obtain the product.
The degradable plastics prepared in the above examples and comparative examples were respectively subjected to the test of mechanical properties and plasticizer mobility (Table 1), in which
And (3) testing mechanical properties: the method is carried out on a material testing machine according to the national standard 1040 and 2006. The stretching speed is 50 mm/min;
testing of Water absorption: water absorption testing was carried out according to GB/T1034-2008. Drying the sample in a 50 ℃ oven for at least 24h, cooling to room temperature in a dryer, weighing mo, soaking the sample in a container filled with distilled water for 24h, taking out, wiping off surface moisture, and weighing m 1; water absorption (%) - (m)1-m0)/m0×100％。
TABLE 1 mechanical property and water absorption of degradable plastic film
As can be seen from the data in Table 1, the degradable plastic prepared by the invention has better mechanical property, and the water absorption is obviously reduced compared with the prior art, which shows that the water resistance is better. The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (4)
1. A corn whole meal degradable plastic film, which comprises the following components: 30-70 parts of corn flour, 40-65 parts of polyvinyl alcohol, 15-30 parts of carboxymethyl cellulose, 8-20 parts of ionic liquid plasticizer, 2-6 parts of urea and 3-8 parts of resorcinol bis (diphenyl phosphate); it is characterized in that the preparation method is characterized in that,
the ionic liquid plasticizer has the following structure
2. The corn flour degradable plastic film as claimed in claim 1, wherein the preparation method of the ionic liquid plasticizer is synthesized by adopting the following technical route:
3. the corn flour degradable plastic film as claimed in claim 1, wherein the resorcinol bis (diphenylphosphate) is an organic phosphorus flame retardant, and a small amount of the resorcinol bis (diphenylphosphate) is added to effectively improve the flame retardant property of the film.
4. The method for preparing the degradable plastic film of any one of claims 1 to 3, which mainly comprises the following steps:
(1) gelatinization of corn full starch: placing a certain amount of whole corn flour in a three-necked bottle, adding deionized water, stirring uniformly to fully swell the whole corn flour, then adding polyvinyl alcohol and urea into the three-necked bottle according to a mass ratio, mixing with the whole corn flour after dissolving, stirring and heating to 90 ℃, and carrying out heat preservation reaction for 30-40min to gelatinize corn starch;
(2) mixing materials: sequentially adding a certain amount of the methyl cellulose, the ionic liquid plasticizer and the flame retardant into the gelatinized corn starch according to the mass ratio, and violently stirring and blending for 2 hours at the temperature of 80-90 ℃;
(3) molding: pouring the blending liquid prepared in the step 2 on a horizontal glass plate for tape casting, and uncovering the film after air drying to prepare the degradable plastic film.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114591582A (en) * | 2022-03-18 | 2022-06-07 | 深圳市明星盛包装集团有限公司 | Photo-biodegradable plastic film and preparation method thereof |
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2021
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114591582A (en) * | 2022-03-18 | 2022-06-07 | 深圳市明星盛包装集团有限公司 | Photo-biodegradable plastic film and preparation method thereof |
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Application publication date: 20210608 |