Environment-friendly degradable bio-based material and preparation method thereof

Abstract

The invention relates to the technical field of degradable materials, and discloses an environment-friendly degradable bio-based material and a preparation method thereof. The degradable biological material comprises the following raw materials in parts by weight: 55-65 parts of polylactic resin, 7-10 parts of a composite flame retardant, 3-6 parts of a flexibilizer, 2-4 parts of a plasticizer, 1.5-2.5 parts of an antioxidant, 5-10 parts of calcium carbonate and 1-2 parts of a lubricant. According to the material, degradable polylactic resin is adopted as a main raw material, and a composite flame retardant with biodegradability and other functional aids are added, so that the degradability and flame retardance of the biological material are comprehensively improved; wherein the composite flame retardant is synthesized from sodium alginate, a phosphate structure, a furan structure, organic silicon and other raw materials, and compared with a traditional flame retardant, the composite flame retardant has biodegradability and better flame retardance.

Description

Technical Field

[0001] The present invention relates to the technical field of degradable materials, and in particular to an environmentally friendly degradable bio-based material and a preparation method thereof. Background Art

[0002] Polylactic acid (PLA) is a polymer material made from starch-based biomass such as corn and potatoes or straw cellulose, which is produced by fermentation to produce lactic acid and further polymerized. It is environmentally friendly, non-toxic, antibacterial, flame-retardant, and has good biocompatibility. It can be completely biodegraded under normal composting conditions. The degradation products of polylactic acid are carbon dioxide and water, which are pollution-free to the environment. Therefore, it is considered to be the most promising biodegradable material to replace traditional petroleum-based plastics (such as PE, PP, PVC, etc.) in the future.

[0003] Although polylactic acid has good biodegradability and biocompatibility, its flammability limits its application in the field of high flame retardancy. In order to overcome the disadvantage of poor flame retardancy of polylactic acid materials, researchers have improved the flame retardant properties of materials by adding flame retardants. Existing flame retardants are mainly halogen flame retardants, inorganic flame retardants or phosphate flame retardants. When these flame retardants are used alone in the matrix, they need to be added in large quantities to achieve the required flame retardant effect. However, the large-scale use of additives will cause the mechanical properties of the material to deteriorate. Therefore, it is necessary to develop a flame retardant that can effectively flame retard and use less to meet actual needs. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides an environmentally friendly and degradable bio-based material and a preparation method thereof.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] An environmentally friendly and degradable bio-based material, comprising the following raw materials in parts by weight: 55-65 parts of polylactic acid resin, 7-10 parts of composite flame retardant, 3-6 parts of toughening agent, 2-4 parts of plasticizer, 1.5-2.5 parts of antioxidant, 5-10 parts of calcium carbonate, and 1-2 parts of lubricant;

[0007] The toughening agent is maleic anhydride grafted POE, the plasticizer is citrate, the lubricant is zinc stearate, and the antioxidant is antioxidant 1010;

[0008] The composite flame retardant is prepared by the following steps:

[0009] Step A1, 2-amino-1,3-propanediol, diphenyl chlorophosphate, triethylamine and dichloromethane are mixed, and stirred in an ice-water bath for 40-60 minutes, then heated to room temperature and stirred for 12 hours, filtered, washed and dried to obtain a terminal hydroxyl phosphate derivative;

[0010] Further, in step A1, the molar ratio of 2-amino-1,3-propanediol, diphenyl chlorophosphate and triethylamine is 1-1.1:1:1;

[0011] Step A2, mixing the terminal hydroxyl phosphate derivative and glyoxylic acid and heating to 100° C., stirring for 20-40 min, adding cyclohexane and p-toluenesulfonic acid, introducing nitrogen and heating to 120-130° C. for reaction for 1 h, and vacuum reaction for 2 h to obtain the terminal aldehyde phosphate derivative;

[0012] Further, in step A2, the usage ratio of the terminal hydroxy phosphate derivative, glyoxylic acid, cyclohexane and p-toluenesulfonic acid is 0.1-0.2 mol: 0.2-0.4 mol: 5-10 mL: 0.06-0.08 g;

[0013] Step A3, mix furfurylamine and DMF (N,N-dimethylformamide), adjust the pH to 5.0-5.5, add the terminal aldehyde phosphate derivative, and heat to 70-80° C. to react for 4-5 hours, distill under reduced pressure, and dry to obtain the furan-phosphate derivative;

[0014] Further, in step A3, the molar ratio of the terminal aldehyde phosphate derivative to furfurylamine is 1:2;

[0015] Step A4, mixing the modified sodium alginate and isopropanol, introducing nitrogen and heating to 70-80° C., adding furan-phosphate derivative and chloroplatinic acid isopropanol solution, stirring and reacting for 3-6 hours, and distilling under reduced pressure to obtain a composite flame retardant;

[0016] Further, in step A4, the usage ratio of modified sodium alginate, furan-phosphate derivative, isopropanol and chloroplatinic acid isopropanol solution is 5-10 g: 1-3 g: 100 mL: 10 mL;

[0017] Furthermore, in step A4, the dosage ratio of chloroplatinic acid to isopropanol is 0.1-0.3 g:10 mL.

[0018] The modified sodium alginate is prepared by the following steps:

[0019] Step B1, tetramethyldihydrogendisiloxane and N-(β-aminoethyl-γ-aminopropyl)methyldimethoxysilane are mixed, water and sulfuric acid are added, and the mixture is reacted at 15° C. for 3-5 hours, the pH of the system is adjusted to be neutral, and the mixture is washed and dried to obtain hydrogen-containing organosilicon;

[0020] Further, in step B1, the usage ratio of tetramethyldihydrogendisiloxane, N-(β-aminoethyl-γ-aminopropyl)methyldimethoxysilane, water and sulfuric acid is 0.15-0.25 mol: 0.1 mol: 0.5-2 mL: 0.003-0.005 mol;

[0021] Step B2, mix sodium alginate in DMF, add EDC (1-ethyl-(3-dimethylaminopropyl)carbodiimide) and NHS (N-hydroxysuccinimide) and stir for 15 minutes, then add hydrogen-containing organosilicon and react for 24 hours, filter, wash and dry to obtain modified sodium alginate;

[0022] Furthermore, in step B2, the usage ratio of sodium alginate, DMF, EDC, NHS and hydrogen-containing organosilicon is 10 g: 200 mL: 0.02 mol: 0.01 mol: 2-4 g.

[0023] A method for preparing an environmentally friendly and degradable bio-based material comprises the following steps:

[0024] The raw materials are weighed by weight, polylactic acid resin, composite flame retardant, toughening agent, plasticizer, antioxidant, calcium carbonate and lubricant are uniformly mixed, and put into a twin-screw extruder for melt extrusion, cooling and granulation to obtain an environmentally friendly and degradable bio-based material.

[0025] Beneficial effects of the present invention:

[0026] The degradable biomaterial in the present invention adopts degradable polylactic acid resin as the main raw material, and adds a composite flame retardant with biodegradability and other functional additives, which comprehensively improves the degradability and flame retardant properties of the biomaterial; wherein the composite flame retardant is synthesized from raw materials such as sodium alginate, phosphate structure, furan structure and silicone, and is biodegradable and has better flame retardant properties than traditional flame retardants.

[0027] The composite flame retardant of the present invention utilizes the synergistic effect between sodium alginate, phosphate structure, furan structure and organosilicon to improve the flame retardant performance of the matrix; wherein, sodium alginate is used as the main flame retardant matrix, and the polysaccharide structure of sodium alginate is utilized to form a dense carbon layer during the combustion process, effectively isolating heat, oxygen and combustible gas, thereby preventing the spread of fire, and releasing moisture during the combustion process, and the moisture can dilute the combustible gas and reduce the combustion speed; the phosphate structure and organosilicon can form a heat-insulating protective layer on the surface of the material during combustion to prevent heat transfer; in addition, the furan ring in the flame retardant has the effect of cross-linking and carbonizing, thereby improving the carbonization of the polylactic acid material, and the generated cross-linked carbon layer plays a physical barrier role, protecting the bottom fabric from further flame damage, thereby blocking the feedback of heat and the volatilization of some combustible degradation products, and finally inhibiting the melting drop behavior of the material. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Example 1: Modified sodium alginate is prepared by the following steps:

[0030] Step B1, 0.15 mol of tetramethyldihydrogendisiloxane and 0.1 mol of N-(β-aminoethyl-γ-aminopropyl)methyldimethoxysilane were mixed, 0.5 mL of water and 0.003 mol of sulfuric acid were added, and the mixture was reacted at 15° C. for 3 h, the pH of the system was adjusted to neutral, and the mixture was washed and dried to obtain hydrogenated organosilicon;

[0031] Step B2: 10 g of sodium alginate was mixed in 200 mL of DMF, 0.02 mol of EDC and 0.01 mol of NHS were added and stirred for 15 min, and then 2 g of hydrogen-containing organosilicon was added and reacted for 24 h, filtered, washed and dried to obtain modified sodium alginate.

[0032] The composite flame retardant is prepared by the following steps:

[0033] Step A1, 0.1 mol of 2-amino-1,3-propanediol, 0.1 mol of diphenyl chlorophosphate, 0.1 mol of triethylamine and 100 mL of dichloromethane were mixed, and stirred in an ice-water bath for 40 min, then heated to room temperature and stirred for 12 h, filtered, washed and dried to obtain a terminal hydroxyl phosphate derivative;

[0034] Step A2, 0.1 mol of terminal hydroxyl phosphate derivative and 0.2 mol of glyoxylic acid were mixed and heated to 100° C., stirred for 20 min, 5 mL of cyclohexane and 0.06 g of p-toluenesulfonic acid were added, nitrogen was introduced and the temperature was raised to 120° C. for reaction for 1 h, and vacuum reaction was performed for 2 h to obtain the terminal aldehyde phosphate derivative;

[0035] Step A3, 0.2 mol of furfurylamine and 100 mL of DMF were mixed, the pH was adjusted to 5.0, 0.1 mol of terminal aldehyde phosphate derivative was added, and the temperature was raised to 70° C. for reaction for 4 h, and the mixture was distilled under reduced pressure and dried to obtain a furan-phosphate derivative;

[0036] Step A4: Mix 5 g of modified sodium alginate and 100 mL of isopropanol, introduce nitrogen and heat to 70°C, add 1 g of furan-phosphate derivative and 10 mL of chloroplatinic acid isopropanol solution, stir and react for 3 h, and distill under reduced pressure to obtain a composite flame retardant. The dosage ratio of chloroplatinic acid and isopropanol in the chloroplatinic acid isopropanol solution is 0.1 g:10 mL.

[0037] Example 2: Modified sodium alginate is prepared by the following steps:

[0038] Step B1, 0.2 mol of tetramethyldihydrogendisiloxane and 0.1 mol of N-(β-aminoethyl-γ-aminopropyl)methyldimethoxysilane were mixed, 1 mL of water and 0.004 mol of sulfuric acid were added, and the mixture was reacted at 15° C. for 4 h, the pH of the system was adjusted to neutral, and the mixture was washed and dried to obtain hydrogenated organosilicon;

[0039] Step B2: 10 g of sodium alginate was mixed in 200 mL of DMF, 0.02 mol of EDC and 0.01 mol of NHS were added and stirred for 15 min, and then 3 g of hydrogen-containing organosilicon was added and reacted for 24 h, filtered, washed and dried to obtain modified sodium alginate.

[0040] The composite flame retardant is prepared by the following steps:

[0041] Step A1, 0.105 mol of 2-amino-1,3-propanediol, 0.1 mol of diphenyl chlorophosphate, 0.1 mol of triethylamine and 100 mL of dichloromethane were mixed, and stirred in an ice-water bath for 50 min, then heated to room temperature and stirred for 12 h, filtered, washed and dried to obtain a terminal hydroxyl phosphate derivative;

[0042] Step A2, 0.15 mol of terminal hydroxyl phosphate derivative and 0.3 mol of glyoxylic acid were mixed and heated to 100° C., stirred for 30 min, 7.5 mL of cyclohexane and 0.07 g of p-toluenesulfonic acid were added, nitrogen was introduced and the temperature was raised to 125° C. for reaction for 1 h, and vacuum reaction was performed for 2 h to obtain the terminal aldehyde phosphate derivative;

[0043] Step A3, 0.2 mol of furfurylamine and 100 mL of DMF were mixed, the pH was adjusted to 5.2, 0.1 mol of terminal aldehyde phosphate derivative was added, and the temperature was raised to 75° C. for reaction for 4.5 h, and the mixture was distilled under reduced pressure and dried to obtain a furan-phosphate derivative;

[0044] Step A4: Mix 7.5 g of modified sodium alginate and 100 mL of isopropanol, introduce nitrogen and heat to 75°C, add 2 g of furan-phosphate derivative and 10 mL of chloroplatinic acid isopropanol solution, stir and react for 4.5 h, and distill under reduced pressure to obtain a composite flame retardant. The amount ratio of chloroplatinic acid and isopropanol in the chloroplatinic acid isopropanol solution is 0.2 g:10 mL.

[0045] Example 3: Modified sodium alginate is prepared by the following steps:

[0046] Step B1, 0.25 mol of tetramethyldihydrogendisiloxane and 0.1 mol of N-(β-aminoethyl-γ-aminopropyl)methyldimethoxysilane were mixed, 2 mL of water and 0.005 mol of sulfuric acid were added, and the mixture was reacted at 15° C. for 5 h, the pH of the system was adjusted to neutral, and the mixture was washed and dried to obtain hydrogen-containing organosilicon;

[0047] Step B2: 10 g of sodium alginate was mixed in 200 mL of DMF, 0.02 mol of EDC and 0.01 mol of NHS were added and stirred for 15 min, and then 4 g of hydrogen-containing organosilicon was added and reacted for 24 h, filtered, washed and dried to obtain modified sodium alginate.

[0048] The composite flame retardant is prepared by the following steps:

[0049] Step A1, 0.11 mol of 2-amino-1,3-propanediol, 0.1 mol of diphenyl chlorophosphate, 0.1 mol of triethylamine and 100 mL of dichloromethane were mixed, and stirred in an ice-water bath for 60 min, then heated to room temperature and stirred for 12 h, filtered, washed and dried to obtain a terminal hydroxyl phosphate derivative;

[0050] Step A2, 0.2 mol of terminal hydroxyl phosphate derivative and 0.4 mol of glyoxylic acid were mixed and heated to 100° C., stirred for 40 min, 10 mL of cyclohexane and 0.08 g of p-toluenesulfonic acid were added, nitrogen was introduced and the temperature was raised to 130° C. for reaction for 1 h, and vacuum reaction was performed for 2 h to obtain the terminal aldehyde phosphate derivative;

[0051] Step A3, 0.2 mol of furfurylamine and 100 mL of DMF were mixed, the pH was adjusted to 5.5, 0.1 mol of terminal aldehyde phosphate derivative was added, and the temperature was raised to 80° C. for reaction for 5 h, and the mixture was distilled under reduced pressure and dried to obtain a furan-phosphate derivative;

[0052] Step A4: Mix 10 g of modified sodium alginate and 100 mL of isopropanol, introduce nitrogen and heat to 80°C, add 3 g of furan-phosphate derivative and 10 mL of chloroplatinic acid isopropanol solution, stir and react for 6 h, and distill under reduced pressure to obtain a composite flame retardant. The amount ratio of chloroplatinic acid and isopropanol in the chloroplatinic acid isopropanol solution is 0.3 g:10 mL.

[0053] Example 4: A method for preparing an environmentally friendly and degradable bio-based material comprises the following steps:

[0054] The raw materials were weighed by weight, and 55 parts of polylactic acid resin, 7 parts of the composite flame retardant prepared in Example 1, 3 parts of maleic anhydride grafted POE, 2 parts of citrate, 1.5 parts of antioxidant 1010, 5 parts of calcium carbonate and 1 part of zinc stearate were mixed evenly, put into a twin-screw extruder for melt extrusion, cooled and granulated to obtain an environmentally friendly and degradable bio-based material.

[0055] Example 5: A method for preparing an environmentally friendly and degradable bio-based material comprises the following steps:

[0056] The raw materials were weighed by weight, and 60 parts of polylactic acid resin, 8.5 parts of the composite flame retardant prepared in Example 2, 4.5 parts of maleic anhydride grafted POE, 3 parts of citrate, 2 parts of antioxidant 1010, 7.5 parts of calcium carbonate and 1.5 parts of zinc stearate were mixed evenly, put into a twin-screw extruder for melt extrusion, cooled and granulated to obtain an environmentally friendly and degradable bio-based material.

[0057] Example 6: A method for preparing an environmentally friendly and degradable bio-based material comprises the following steps:

[0058] The raw materials were weighed by weight, and 65 parts of polylactic acid resin, 10 parts of the composite flame retardant prepared in Example 3, 6 parts of maleic anhydride grafted POE, 4 parts of citrate, 2.5 parts of antioxidant 1010, 10 parts of calcium carbonate and 2 parts of zinc stearate were mixed evenly, put into a twin-screw extruder for melt extrusion, cooled and granulated to obtain an environmentally friendly and degradable bio-based material.

[0059] Comparative Example 1: This comparative example is a degradable bio-based material. The difference from Example 6 is that magnesium hydroxide is used instead of the composite flame retardant prepared in Example 3, and the rest is the same.

[0060] Comparative Example 2: This comparative example is a degradable bio-based material. The difference from Example 6 is that furan-phosphate derivatives are used instead of the composite flame retardant prepared in Example 3, and the rest are the same.

[0061] Comparative Example 3: This comparative example is a degradable bio-based material. The difference from Example 6 is that modified sodium alginate is used instead of the composite flame retardant prepared in Example 3, and the rest are the same.

[0062] The degradable bio-based materials prepared in Examples 4-6 and Comparative Examples 1-3 were subjected to performance tests:

[0063] Degradability test: Degradation rate of the degradable bio-based materials prepared in the examples and comparative examples after 6 months of composting was determined according to GB / T 19277.1-2011 "Determination of the ultimate aerobic biodegradability of materials under controlled composting conditions using the method of measuring the released carbon dioxide";

[0064] Flame retardant test: The materials obtained in the examples and comparative examples were made into strips with a thickness of 3.2 mm, and the vertical combustion performance of each strip was measured according to the UL-94 standard;

[0065] The test results are shown in Table 1:

[0066] Table 1: Performance test results

[0067]

[0068] As can be seen from Table 1, the degradation rate of the biodegradable bio-based material prepared by the present invention is (95.3-96.1)% after the degradation test and the flame retardant performance test, and the flame retardant grade is V0, indicating that the biodegradable bio-based material has not only excellent degradation performance, but also excellent flame retardant performance.

[0069] The above contents are merely examples and explanations of the concept of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the scope defined by the concept of the invention, they should all fall within the protection scope of the present invention.

Claims

1. An environmentally friendly and degradable bio-based material, characterized in that: The invention comprises the following raw materials in parts by weight: 55-65 parts of polylactic acid resin, 7-10 parts of composite flame retardant, 3-6 parts of toughening agent, 2-4 parts of plasticizer, 1.5-2.5 parts of antioxidant, 5-10 parts of calcium carbonate and 1-2 parts of lubricant; The toughening agent is maleic anhydride grafted POE, the plasticizer is citrate, the lubricant is zinc stearate, and the antioxidant is antioxidant 1010; The composite flame retardant is prepared by the reaction of modified sodium alginate and furan-phosphate derivatives, the furan-phosphate derivatives are prepared by the reaction of furfurylamine and terminal aldehyde phosphate derivatives, the terminal aldehyde phosphate derivatives are prepared by the esterification reaction of terminal hydroxyl phosphate derivatives and glyoxylic acid, and the terminal hydroxyl phosphate derivatives are prepared by the reaction of 2-amino-1,3-propanediol and diphenyl chlorophosphate; The modified sodium alginate is prepared by reacting sodium alginate and hydrogen-containing organosilicon through amide, and the hydrogen-containing organosilicon is prepared by reacting tetramethyldihydrodisiloxane and N-(β-aminoethyl-γ-aminopropyl)methyldimethoxysilane.

2. The environmentally friendly and degradable bio-based material according to claim 1, characterized in that: The composite flame retardant is prepared by the following steps: Step A1, 2-amino-1,3-propanediol, diphenyl chlorophosphate, triethylamine and dichloromethane are mixed, and stirred in an ice-water bath for 40-60 minutes, then heated to room temperature and stirred for 12 hours, filtered, washed and dried to obtain a terminal hydroxyl phosphate derivative; Step A2, mixing the terminal hydroxyl phosphate derivative and glyoxylic acid and heating to 100° C., stirring for 20-40 min, adding cyclohexane and p-toluenesulfonic acid, introducing nitrogen and heating to 120-130° C. for reaction for 1 h, and vacuum reaction for 2 h to obtain the terminal aldehyde phosphate derivative; Step A3, mix furfurylamine and DMF, adjust the pH to 5.0-5.5, add the terminal aldehyde phosphate derivative, and heat to 70-80° C. for reaction for 4-5 hours, distill under reduced pressure, and dry to obtain the furan-phosphate derivative; Step A4, the modified sodium alginate and isopropanol are mixed, nitrogen is introduced and the temperature is raised to 70-80° C., furan-phosphate derivative and chloroplatinic acid isopropanol solution are added, the mixture is stirred for reaction for 3-6 hours, and vacuum distilled to obtain a composite flame retardant.

3. The environmentally friendly and degradable bio-based material according to claim 2, characterized in that: In step A1, the molar ratio of 2-amino-1,3-propanediol, diphenyl chlorophosphate and triethylamine is 1-1.1:1:

1.

4. The environmentally friendly and degradable bio-based material according to claim 2, characterized in that: In step A2, the usage ratio of the terminal hydroxy phosphate derivative, glyoxylic acid, cyclohexane and p-toluenesulfonic acid is 0.1-0.2 mol: 0.2-0.4 mol: 5-10 mL: 0.06-0.08 g.

5. The environmentally friendly and degradable bio-based material according to claim 2, characterized in that: In step A3, the molar ratio of the terminal aldehyde phosphate derivative to furfurylamine is 1:

2.

6. The environmentally friendly and degradable bio-based material according to claim 2, characterized in that: In step A4, the amount ratio of modified sodium alginate, furan-phosphate derivative, isopropanol and chloroplatinic acid isopropanol solution is 5-10 g: 1-3 g: 100 mL: 10 mL, and the amount ratio of chloroplatinic acid and isopropanol in the chloroplatinic acid isopropanol solution is 0.1-0.3 g: 10 mL.

7. The environmentally friendly and degradable bio-based material according to claim 1, characterized in that: The modified sodium alginate is prepared by the following steps: Step B1, tetramethyldihydrogendisiloxane and N-(β-aminoethyl-γ-aminopropyl)methyldimethoxysilane are mixed, water and sulfuric acid are added, and the mixture is reacted at 15° C. for 3-5 hours, the pH of the system is adjusted to be neutral, and the mixture is washed and dried to obtain hydrogen-containing organosilicon; Step B2: Mix sodium alginate in DMF, add EDC and NHS and stir for 15 minutes, then add hydrogen-containing organosilicon and react for 24 hours, filter, wash and dry to obtain modified sodium alginate.

8. The environmentally friendly and degradable bio-based material according to claim 7, characterized in that: In step B1, the usage ratio of tetramethyldihydrogendisiloxane, N-(β-aminoethyl-γ-aminopropyl)methyldimethoxysilane, water and sulfuric acid is 0.15-0.25 mol: 0.1 mol: 0.5-2 mL: 0.003-0.005 mol.

9. The environmentally friendly and degradable bio-based material according to claim 7, characterized in that: In step B2, the usage ratio of sodium alginate, DMF, EDC, NHS and hydrogen-containing organosilicon is 10 g: 200 mL: 0.02 mol: 0.01 mol: 2-4 g.

10. A method for preparing the environmentally friendly and degradable bio-based material according to any one of claims 1 to 9, characterized in that: The following steps are involved: The raw materials are weighed by weight, polylactic acid resin, composite flame retardant, toughening agent, plasticizer, antioxidant, calcium carbonate and lubricant are uniformly mixed, and put into a twin-screw extruder for melt extrusion, cooling and granulation to obtain an environmentally friendly and degradable bio-based material.

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