A kind of anti-aging polypropylene material and preparation method thereof

Abstract

The invention discloses an anti-aging polypropylene material and a preparation method thereof. Polypropylene and a modifying additive are melt-blended so that double bonds on the modifying additive are grafted onto molecules on the polypropylene, and the coordination between the modifying additive and the polypropylene molecules is enhanced to obtain the modified polypropylene. The modified polypropylene is immersed in an aqueous solution of ferric nitrate, and the imidazole groups on the surface of the modified polypropylene can coordinate with iron ions for cross-linking to form an iron complex on the surface. When irradiated with ultraviolet light, the excited state of the molecules or groups excited by the ultraviolet light can be quenched to return to the ground state, and the energy can be dissipated in the form of heat, fluorescence and phosphorescence. At the same time, the iron complex on the surface can block the ultraviolet light from directly irradiating the polypropylene molecules. The modifier contains a hindered amine structure, which is converted into a nitroxide free radical after being irradiated with light, and can capture the free radicals generated by the polymer and inactivate them, thereby generating corresponding esters and peroxide esters, and increasing the service life of the polypropylene material.

Description

Technical Field

[0001] The invention relates to the technical field of polypropylene material preparation, and in particular to an anti-aging polypropylene material and a preparation method thereof. Background Art

[0002] Polypropylene is cheap, lightweight, corrosion-resistant, and has good molding and processing properties. It is widely used in packaging, automotive parts, building materials, and other fields. It is one of the three major general-purpose plastics. With the development of the plastics industry, more and more plastics are used in various parts of life. As time goes by, plastic products are inevitably aged, damaged, and discarded. Polypropylene is a common polymer material with good performance and a wide range of applications, and its waste volume is also increasing year by year. However, due to the unstable tertiary carbon atoms in its structure, polypropylene is particularly sensitive to light. When used outdoors, it is very easy to age, and it will turn yellow, become brittle, and crack on the surface. More seriously, it can cause a significant decrease in mechanical properties such as tensile strength, impact strength, bending strength, and elongation at break, and lose its use value. Summary of the invention

[0003] The purpose of the present invention is to provide an anti-aging polypropylene material and a preparation method thereof, which solves the problems of the current polypropylene material and the preparation method thereof.

[0004] The purpose of the present invention can be achieved through the following technical solutions:

[0005] A method for preparing an anti-aging polypropylene material comprises the following steps:

[0006] Step S1: uniformly mix magnesium nitrate hexahydrate, aluminum nitrate nonahydrate and deionized water, stir and add sodium hydroxide and sodium dodecyl sulfate at a speed of 150-200 r / min and a temperature of 20-25° C., and react for 10-15 hours to obtain a precursor;

[0007] Step S2: dispersing the precursor in deionized water, stirring and adding a modifier and sodium hydroxide at a speed of 120-150 r / min and a temperature of 25-30° C., reacting for 20-25 hours, filtering and removing the filtrate, dispersing the substrate in DMF, adding a reinforcing agent, and irradiating under 365 nm ultraviolet light for 15-30 seconds to obtain a modified additive;

[0008] Step S3: Add polypropylene, modification additives and benzoyl peroxide into an internal mixer, blend them evenly at a temperature of 180-190° C. to obtain modified polypropylene, keep the modified polypropylene, ferric nitrate and deionized water warm for 3-5 days at a speed of 60-80 r / min and a temperature of 100-105° C., cool to room temperature, continue to keep warm for 1 day, filter and dry to obtain an anti-aging polypropylene material.

[0009] Furthermore, the amount ratio of magnesium nitrate hexahydrate, aluminum nitrate nonahydrate, deionized water, sodium hydroxide and sodium dodecyl sulfate in step S1 is 3mmol:1mmol:10mL:18mmol:2mmol.

[0010] Furthermore, the mass ratio of the precursor, modifier, sodium hydroxide and enhancer described in step S2 is 3:20:8:30.

[0011] Furthermore, the mass ratio of the polypropylene, the modified additive and the benzoyl peroxide in step S3 is 100:30:3, and the amount ratio of the modified polypropylene, ferric nitrate and deionized water is 6g:0.5g:15mL.

[0012] Further, the modifier is prepared by the following steps:

[0013] 1,2,2,6,6-pentamethylpiperidinol, epichlorohydrin and DMF are mixed evenly, stirred and sodium hydroxide solution is added to keep the pH value at 12 at a speed of 150-200 r / min and a temperature of 30-40°C, and the reaction is carried out for 6-8 hours to obtain intermediate 1. Intermediate 1, ethylenediamine and DMF are mixed evenly, and the reaction is carried out for 4-6 hours at a speed of 120-150 r / min, a temperature of 20-25°C and a pH value of 10-11. The mixture is adjusted to neutral, acryloyl chloride is added, and the reaction is continued for 1-1.5 hours to obtain a modifier.

[0014] Furthermore, the molar ratio of 1,2,2,6,6-pentamethylpiperidinol to epichlorohydrin is 1:1, and the molar ratio of intermediate 1, ethylenediamine and acryloyl chloride is 4:1:4.

[0015] Furthermore, the reinforcing agent is prepared by the following steps:

[0016] Step B1: 3-aminopropylmethyldiethoxysilane, maleic anhydride and DMF are mixed uniformly, stirred for 10-15 minutes at a speed of 150-200 r / min and a temperature of 5-10° C., and then heated to 55-60° C. for reaction for 30-40 minutes, triethylamine, acetic anhydride and nickel acetate are added, and the reaction is continued for 2-3 hours to obtain a modified monomer;

[0017] Step B2: Mix the modified monomer, 3-mercaptopropylmethyldimethoxysilane and deionized water, stir for 10-15 minutes at a speed of 200-300 r / min and a temperature of 60-70° C., add concentrated sulfuric acid and 1,1,3,3-tetramethyldisiloxane, react for 4-6 hours, adjust the pH to neutral, and obtain dihydrogen-terminated polysiloxane;

[0018] Step B3: Mix the dihydrogen-terminated polysiloxane and DMF evenly, stir and add chloroplatinic acid at a speed of 150-200 r / min and a temperature of 50-60°C, react for 10-15 hours, add 4-vinylbenzaldehyde, and continue to react for 6-8 hours to obtain modified polysiloxane, mix the modified polysiloxane, o-phenylenediamine, sodium metabisulfite and DMF evenly, react for 1-1.5 hours at a speed of 150-200 r / min and a temperature of 150-160°C to obtain a strengthener.

[0019] Furthermore, the usage ratio of 3-aminopropylmethyldiethoxysilane, maleic anhydride, triethylamine, acetic anhydride and nickel acetate in step B1 is 50mmol:50mmol:5mL:12mL:3.5g.

[0020] Furthermore, the amount ratio of the modified monomer, 3-mercaptopropylmethyldimethoxysilane, deionized water and 1,1,3,3-tetramethyldisiloxane described in step B2 is 2mmol:1mmol:20mL:1.5mmol, and the amount of concentrated sulfuric acid is 1-1.5% of the total mass of the modified monomer, 3-aminopropylmethyldiethoxysilane and 1,1,3,3-tetramethyldisiloxane.

[0021] Furthermore, the molar ratio of the dihydrogen-terminated polysiloxane and 4-vinylbenzaldehyde in step B3 is 1:2, the concentration of chloroplatinic acid in the mixed solution of dihydrogen-terminated polysiloxane, 4-vinylbenzaldehyde and DMF is 10-15ppm, and the amount ratio of modified polysiloxane, o-phenylenediamine and sodium metabisulfite is 2.5mmol:5mmol:1g.

[0022] The beneficial effects of the present invention are as follows: an anti-aging polypropylene material prepared by the present invention uses magnesium nitrate hexahydrate and aluminum nitrate nonahydrate as raw materials to form a hydrotalcite structure through a hydrothermal synthesis method to prepare a precursor, the precursor and the modifier are subjected to ion exchange, so that the modifier molecules are inserted into the interlayer of the precursor, and then a reinforcing agent is added. Under light conditions, the double bonds on the modifier molecules react with the thiol groups on the reinforcing agent. The thiol groups on the reinforcing agent molecules and the double bonds are prevented from reacting by controlling the irradiation time and the amount of the reinforcing agent added, so as to prepare a modified additive, and polypropylene and the modified additive are melt-blended so that the double bonds on the modified additive are grafted into the polypropylene molecules to enhance the modified additive. The additive is combined with polypropylene molecules to obtain modified polypropylene. The modified polypropylene is immersed in an aqueous solution of ferric nitrate. The imidazole groups on the surface of the modified polypropylene can be coordinated with iron ions for cross-linking to form iron complexes on the surface. When irradiated with ultraviolet light, the excited state of the molecules or groups excited by ultraviolet light can be quenched, returning them to the ground state, and emitting energy in the form of heat, fluorescence and phosphorescence. At the same time, the iron complex on the surface can block ultraviolet light from directly irradiating the polypropylene molecules, thereby increasing the anti-aging property of the material. The modifier uses 1,2,2,6,6-pentamethylpiperidinol and epichlorohydrin as raw materials to make 1,2,2,6,6-pentamethylpiperidinol The alcoholic hydroxyl group on the 1,1-piperidinol reacts with the epoxy group on the epichlorohydrin, and then the ring is closed under alkaline conditions to obtain intermediate 1, and intermediate 1 is reacted with ethylenediamine, so that the epoxy group on the intermediate 1 reacts with the amino group on the ethylenediamine to form a new alcoholic hydroxyl group, and then reacts with acryloyl chloride, so that the acyl chloride reacts with the hydroxyl group to obtain a modifier. The modifier contains a hindered amine structure, which is converted into a nitroxide free radical after being exposed to light, and can capture the free radicals generated by the polymer and inactivate them to generate corresponding esters and peroxy esters. The enhancer uses 3-aminopropylmethyldiethoxysilane and maleic anhydride as raw materials, so that the maleic anhydride is opened and reacts with 3-aminopropylmethyldiethoxy The amino group on the silane is reacted and then ring-closed to obtain a modified monomer. The modified monomer and 3-mercaptopropylmethyldimethoxysilane are first hydrolyzed and then polymerized with 1,1,3,3-tetramethyldisiloxane to form a dihydrogen-terminated polysiloxane. The dihydrogen-terminated polysiloxane is reacted with 4-vinylbenzaldehyde so that Si-H on the dihydrogen-terminated polysiloxane reacts with the double bond on 4-vinylbenzaldehyde to obtain a modified polysiloxane. The modified polysiloxane is reacted with o-phenylenediamine so that the benzaldehyde agent reacts with o-phenylenediamine to form imidazole. The main chain of the strengthener molecule is an organic silicon segment, which can enhance the heat-oxidative aging resistance of the polypropylene material, thereby increasing the service life of the polypropylene material. DETAILED DESCRIPTION

[0023] 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.

[0024] Example 1

[0025] A method for preparing an anti-aging polypropylene material comprises the following steps:

[0026] Step S1: uniformly mix magnesium nitrate hexahydrate, aluminum nitrate nonahydrate and deionized water, stir and add sodium hydroxide and sodium dodecyl sulfate at a speed of 150 r / min and a temperature of 20° C., and react for 10 hours to obtain a precursor;

[0027] Step S2: dispersing the precursor in deionized water, stirring and adding a modifier and sodium hydroxide at a speed of 120 r / min and a temperature of 25° C., reacting for 20 hours, filtering and removing the filtrate, dispersing the substrate in DMF, adding a reinforcing agent, and irradiating under 365 nm ultraviolet light for 15 seconds to obtain a modified additive;

[0028] Step S3: Add polypropylene, modification additives and benzoyl peroxide into an internal mixer, blend them evenly at a temperature of 180° C. to obtain modified polypropylene, and keep the modified polypropylene, ferric nitrate and deionized water at a speed of 60 r / min and a temperature of 100° C. for 3 days, cool to room temperature, continue to keep the temperature for 1 day, filter and dry to obtain an anti-aging polypropylene material.

[0029] The amount ratio of magnesium nitrate hexahydrate, aluminum nitrate nonahydrate, deionized water, sodium hydroxide and sodium dodecyl sulfate described in step S1 is 3mmol:1mmol:10mL:18mmol:2mmol.

[0030] The mass ratio of the precursor, modifier, sodium hydroxide and enhancer described in step S2 is 3:20:8:30.

[0031] The mass ratio of the polypropylene, the modified additive and the benzoyl peroxide in step S3 is 100:30:3, the polypropylene model is k7003, and the amount ratio of the modified polypropylene, ferric nitrate and deionized water is 6g:0.5g:15mL.

[0032] The modifier is prepared by the following steps:

[0033] 1,2,2,6,6-pentamethylpiperidinol, epichlorohydrin and DMF were mixed evenly, stirred at a speed of 150 r / min and a temperature of 30°C, and sodium hydroxide solution was added to keep the pH value at 12, and the reaction was carried out for 6 hours to obtain intermediate 1. Intermediate 1, ethylenediamine and DMF were mixed evenly, and the reaction was carried out for 4 hours at a speed of 120 r / min, a temperature of 20°C and a pH value of 10, adjusted to neutral, acryloyl chloride was added, and the reaction was continued for 1 hour to obtain a modifier.

[0034] The molar ratio of 1,2,2,6,6-pentamethylpiperidinol to epichlorohydrin is 1:1, and the molar ratio of intermediate 1, ethylenediamine and acryloyl chloride is 4:1:4.

[0035] The reinforcing agent is prepared by the following steps:

[0036] Step B1: 3-aminopropylmethyldiethoxysilane, maleic anhydride and DMF were mixed evenly, stirred for 10 minutes at a speed of 150 r / min and a temperature of 5° C., and then heated to 55° C. for reaction for 30 minutes, triethylamine, acetic anhydride and nickel acetate were added, and the reaction was continued for 2 hours to obtain a modified monomer;

[0037] Step B2: the modified monomer, 3-mercaptopropylmethyldimethoxysilane and deionized water were mixed, and stirred for 10 minutes at a speed of 200 r / min and a temperature of 60° C., and concentrated sulfuric acid and 1,1,3,3-tetramethyldisiloxane were added, and the reaction was carried out for 4 hours, and the pH was adjusted to neutral to obtain a dihydrogen-terminated polysiloxane;

[0038] Step B3: Mix the dihydrogen-terminated polysiloxane and DMF evenly, stir and add chloroplatinic acid at a speed of 150 r / min and a temperature of 50°C, react for 10 hours, add 4-vinylbenzaldehyde, and continue to react for 6 hours to obtain modified polysiloxane; mix the modified polysiloxane, o-phenylenediamine, sodium metabisulfite and DMF evenly, react at a speed of 150 r / min and a temperature of 150°C for 1 hour to obtain a strengthener.

[0039] The amount ratio of 3-aminopropylmethyldiethoxysilane, maleic anhydride, triethylamine, acetic anhydride and nickel acetate in step B1 is 50mmol:50mmol:5mL:12mL:3.5g.

[0040] The amount ratio of the modified monomer, 3-mercaptopropylmethyldimethoxysilane, deionized water and 1,1,3,3-tetramethyldisiloxane described in step B2 is 2mmol:1mmol:20mL:1.5mmol, and the amount of concentrated sulfuric acid is 1% of the total mass of the modified monomer, 3-aminopropylmethyldiethoxysilane and 1,1,3,3-tetramethyldisiloxane.

[0041] The molar ratio of the dihydrogen-terminated polysiloxane and 4-vinylbenzaldehyde in step B3 is 1:2, the concentration of chloroplatinic acid in the mixed solution of dihydrogen-terminated polysiloxane, 4-vinylbenzaldehyde and DMF is 10 ppm, and the amount ratio of modified polysiloxane, o-phenylenediamine and sodium metabisulfite is 2.5 mmol: 5 mmol: 1 g.

[0042] Example 2

[0043] A method for preparing an anti-aging polypropylene material comprises the following steps:

[0044] Step S1: Mix magnesium nitrate hexahydrate, aluminum nitrate nonahydrate and deionized water evenly, stir and add sodium hydroxide and sodium dodecyl sulfate at a speed of 150 r / min and a temperature of 23° C., and react for 13 hours to obtain a precursor;

[0045] Step S2: dispersing the precursor in deionized water, stirring and adding a modifier and sodium hydroxide at a speed of 120 r / min and a temperature of 28° C., reacting for 23 hours, filtering and removing the filtrate, dispersing the substrate in DMF, adding a reinforcing agent, and irradiating under 365 nm ultraviolet light for 20 seconds to obtain a modified additive;

[0046] Step S3: Add polypropylene, modification additives and benzoyl peroxide into an internal mixer, blend them evenly at a temperature of 185° C. to obtain modified polypropylene, and keep the modified polypropylene, ferric nitrate and deionized water at a speed of 60 r / min and a temperature of 103° C. for 4 days, cool to room temperature, continue to keep the temperature for 1 day, filter and dry to obtain an anti-aging polypropylene material.

[0047] The amount ratio of magnesium nitrate hexahydrate, aluminum nitrate nonahydrate, deionized water, sodium hydroxide and sodium dodecyl sulfate described in step S1 is 3mmol:1mmol:10mL:18mmol:2mmol.

[0048] The mass ratio of the precursor, modifier, sodium hydroxide and enhancer described in step S2 is 3:20:8:30.

[0049] The mass ratio of the polypropylene, the modified additive and the benzoyl peroxide in step S3 is 100:30:3, the polypropylene model is k7003, and the amount ratio of the modified polypropylene, ferric nitrate and deionized water is 6g:0.5g:15mL.

[0050] The modifier is prepared by the following steps:

[0051] 1,2,2,6,6-pentamethylpiperidinol, epichlorohydrin and DMF were mixed evenly, stirred at a speed of 150 r / min and a temperature of 35°C, and sodium hydroxide solution was added to keep the pH value at 12, and the reaction was carried out for 7 hours to obtain intermediate 1. Intermediate 1, ethylenediamine and DMF were mixed evenly, and the reaction was carried out for 5 hours at a speed of 120 r / min, a temperature of 23°C and a pH value of 11, and the mixture was adjusted to neutral, acryloyl chloride was added, and the reaction was continued for 1.3 hours to obtain a modifier.

[0052] The molar ratio of 1,2,2,6,6-pentamethylpiperidinol to epichlorohydrin is 1:1, and the molar ratio of intermediate 1, ethylenediamine and acryloyl chloride is 4:1:4.

[0053] The reinforcing agent is prepared by the following steps:

[0054] Step B1: 3-aminopropylmethyldiethoxysilane, maleic anhydride and DMF were mixed evenly, stirred for 15 minutes at a speed of 150 r / min and a temperature of 8° C., and then heated to 58° C. to react for 35 minutes, triethylamine, acetic anhydride and nickel acetate were added, and the reaction was continued for 2.5 hours to obtain a modified monomer;

[0055] Step B2: the modified monomer, 3-mercaptopropylmethyldimethoxysilane and deionized water were mixed, and stirred for 10 minutes at a speed of 200 r / min and a temperature of 65° C., and concentrated sulfuric acid and 1,1,3,3-tetramethyldisiloxane were added, and the reaction was carried out for 5 hours, and the pH was adjusted to neutral to obtain a dihydrogen-terminated polysiloxane;

[0056] Step B3: Mix the dihydrogen-terminated polysiloxane and DMF evenly, stir and add chloroplatinic acid at a speed of 150 r / min and a temperature of 55°C, react for 15 hours, add 4-vinylbenzaldehyde, and continue to react for 7 hours to obtain modified polysiloxane. Mix the modified polysiloxane, o-phenylenediamine, sodium metabisulfite and DMF evenly, react at a speed of 150 r / min and a temperature of 155°C for 1.3 hours to obtain a strengthener.

[0057] The amount ratio of 3-aminopropylmethyldiethoxysilane, maleic anhydride, triethylamine, acetic anhydride and nickel acetate in step B1 is 50mmol:50mmol:5mL:12mL:3.5g.

[0058] The amount ratio of the modified monomer, 3-mercaptopropylmethyldimethoxysilane, deionized water and 1,1,3,3-tetramethyldisiloxane described in step B2 is 2mmol:1mmol:20mL:1.5mmol, and the amount of concentrated sulfuric acid is 1.3% of the total mass of the modified monomer, 3-aminopropylmethyldiethoxysilane and 1,1,3,3-tetramethyldisiloxane.

[0059] The molar ratio of the dihydrogen-terminated polysiloxane and 4-vinylbenzaldehyde in step B3 is 1:2, the concentration of chloroplatinic acid in the mixed solution of dihydrogen-terminated polysiloxane, 4-vinylbenzaldehyde and DMF is 13 ppm, and the amount ratio of modified polysiloxane, o-phenylenediamine and sodium metabisulfite is 2.5 mmol: 5 mmol: 1 g.

[0060] Example 3

[0061] A method for preparing an anti-aging polypropylene material comprises the following steps:

[0062] Step S1: Mix magnesium nitrate hexahydrate, aluminum nitrate nonahydrate and deionized water evenly, stir and add sodium hydroxide and sodium dodecyl sulfate at a speed of 200 r / min and a temperature of 25° C., and react for 15 hours to obtain a precursor;

[0063] Step S2: dispersing the precursor in deionized water, stirring and adding a modifier and sodium hydroxide at a speed of 150 r / min and a temperature of 30° C., reacting for 25 hours, filtering and removing the filtrate, dispersing the substrate in DMF, adding a reinforcing agent, and irradiating under 365 nm ultraviolet light for 30 seconds to obtain a modified additive;

[0064] Step S3: Add polypropylene, modifying additives and benzoyl peroxide into an internal mixer, blend them evenly at a temperature of 190° C. to obtain modified polypropylene, and keep the modified polypropylene, ferric nitrate and deionized water at a speed of 80 r / min and a temperature of 105° C. for 5 days, cool to room temperature, continue to keep the temperature for 1 day, filter and dry to obtain an anti-aging polypropylene material.

[0065] The amount ratio of magnesium nitrate hexahydrate, aluminum nitrate nonahydrate, deionized water, sodium hydroxide and sodium dodecyl sulfate described in step S1 is 3mmol:1mmol:10mL:18mmol:2mmol.

[0066] The mass ratio of the precursor, modifier, sodium hydroxide and enhancer described in step S2 is 3:20:8:30.

[0067] The mass ratio of the polypropylene, the modified additive and the benzoyl peroxide in step S3 is 100:30:3, the polypropylene model is k7003, and the amount ratio of the modified polypropylene, ferric nitrate and deionized water is 6g:0.5g:15mL.

[0068] The modifier is prepared by the following steps:

[0069] 1,2,2,6,6-pentamethylpiperidinol, epichlorohydrin and DMF were mixed evenly, stirred at a speed of 200 r / min and a temperature of 40°C, and sodium hydroxide solution was added to keep the pH value at 12, and the reaction was carried out for 8 hours to obtain intermediate 1. Intermediate 1, ethylenediamine and DMF were mixed evenly, and the reaction was carried out for 6 hours at a speed of 150 r / min, a temperature of 25°C and a pH value of 11. The mixture was adjusted to neutral, acryloyl chloride was added, and the reaction was continued for 1.5 hours to obtain a modifier.

[0070] The molar ratio of 1,2,2,6,6-pentamethylpiperidinol to epichlorohydrin is 1:1, and the molar ratio of intermediate 1, ethylenediamine and acryloyl chloride is 4:1:4.

[0071] The reinforcing agent is prepared by the following steps:

[0072] Step B1: 3-aminopropylmethyldiethoxysilane, maleic anhydride and DMF were mixed evenly, stirred for 15 minutes at a speed of 200 r / min and a temperature of 10° C., and then heated to 60° C. to react for 40 minutes, triethylamine, acetic anhydride and nickel acetate were added, and the reaction was continued for 3 hours to obtain a modified monomer;

[0073] Step B2: the modified monomer, 3-mercaptopropylmethyldimethoxysilane and deionized water were mixed, and stirred for 15 minutes at a speed of 300 r / min and a temperature of 70° C., and concentrated sulfuric acid and 1,1,3,3-tetramethyldisiloxane were added, and the reaction was carried out for 6 hours, and the pH was adjusted to neutral to obtain a dihydrogen-terminated polysiloxane;

[0074] Step B3: Mix the dihydrogen-terminated polysiloxane and DMF evenly, stir and add chloroplatinic acid at a speed of 200 r / min and a temperature of 60°C, react for 15 hours, add 4-vinylbenzaldehyde, and continue to react for 8 hours to obtain modified polysiloxane. Mix the modified polysiloxane, o-phenylenediamine, sodium metabisulfite and DMF evenly, react at a speed of 200 r / min and a temperature of 160°C for 1.5 hours to obtain a strengthener.

[0075] The amount ratio of 3-aminopropylmethyldiethoxysilane, maleic anhydride, triethylamine, acetic anhydride and nickel acetate in step B1 is 50mmol:50mmol:5mL:12mL:3.5g.

[0076] The amount ratio of the modified monomer, 3-mercaptopropylmethyldimethoxysilane, deionized water and 1,1,3,3-tetramethyldisiloxane described in step B2 is 2mmol:1mmol:20mL:1.5mmol, and the amount of concentrated sulfuric acid is 1.5% of the total mass of the modified monomer, 3-aminopropylmethyldiethoxysilane and 1,1,3,3-tetramethyldisiloxane.

[0077] The molar ratio of the dihydrogen-terminated polysiloxane and 4-vinylbenzaldehyde in step B3 is 1:2, the concentration of chloroplatinic acid in the mixed solution of dihydrogen-terminated polysiloxane, 4-vinylbenzaldehyde and DMF is 15 ppm, and the amount ratio of modified polysiloxane, o-phenylenediamine and sodium metabisulfite is 2.5 mmol: 5 mmol: 1 g.

[0078] Comparative Example 1

[0079] Compared with Example 1, no precursor was added in this comparative example, and the remaining steps were the same.

[0080] Comparative Example 2

[0081] Compared with Example 1, no reinforcing agent was added in this comparative example, and the remaining steps were the same.

[0082] Comparative Example 3

[0083] Compared with Example 1, this comparative example uses modified polyethylene as the final product.

[0084] The polypropylene materials obtained in Examples 1-3 and Comparative Examples 1-3 were tested for tensile properties according to ASTM-D638, with a sample thickness of 1 mm, a tensile rate of 50 mm / min, and an irradiation intensity of 600 W / m 2 The cumulative irradiation is 400kWh / m 2 , test the tensile strength after light aging, carry out hot air aging under the conditions of 200℃×30 days, and test the tensile strength after hot air aging. The test results are shown in the following table.

[0085]

[0086] It can be seen from the above table that this application has a very good anti-aging effect.

[0087] 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 concept of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A method for preparing an anti-aging polypropylene material, characterized in that: The specific steps include: Step S1: mixing magnesium nitrate hexahydrate, aluminum nitrate nonahydrate and deionized water, adding sodium hydroxide and sodium dodecyl sulfate, and reacting to obtain a precursor; Step S2: dispersing the precursor in deionized water, stirring and adding a modifier and sodium hydroxide, reacting, filtering and removing the filtrate, dispersing the substrate in DMF, adding a reinforcing agent, and irradiating the substrate under 365 nm ultraviolet light to obtain a modified additive; Step S3: adding polypropylene, a modification additive and benzoyl peroxide into an internal mixer and blending them evenly to obtain modified polypropylene; heat-insulating the modified polypropylene, ferric nitrate and deionized water at high temperature, cooling to room temperature, continuing to heat, filtering and drying to obtain an anti-aging polypropylene material; The amount ratio of magnesium nitrate hexahydrate, aluminum nitrate nonahydrate, deionized water, sodium hydroxide and sodium dodecyl sulfate described in step S1 is 3mmol:1mmol:10mL:18mmol:2mmol; The mass ratio of the precursor, modifier, sodium hydroxide and enhancer in step S2 is 3:20:8:30; The mass ratio of the polypropylene, the modified additive and the benzoyl peroxide in step S3 is 100:30:3, and the amount ratio of the modified polypropylene, the ferric nitrate and the deionized water is 6g:0.5g:15mL; The modifier is prepared by the following steps: 1,2,2,6,6-pentamethylpiperidinol, epichlorohydrin and DMF are mixed and stirred, and a sodium hydroxide solution is added to keep the pH value at 12, and the reaction is carried out to obtain an intermediate 1. The intermediate 1, ethylenediamine and DMF are mixed and reacted, and acryloyl chloride is added, and the reaction is continued to obtain a modifier; The molar ratio of 1,2,2,6,6-pentamethylpiperidinol to epichlorohydrin is 1:1, and the molar ratio of intermediate 1, ethylenediamine and acryloyl chloride is 4:1:4; The reinforcing agent is prepared by the following steps: Step B1: 3-aminopropylmethyldiethoxysilane, maleic anhydride and DMF are mixed and stirred, the temperature is raised for reaction, triethylamine, acetic anhydride and nickel acetate are added, and the reaction is continued to obtain a modified monomer; Step B2: After the modified monomer, 3-mercaptopropylmethyldimethoxysilane and deionized water are mixed and stirred, concentrated sulfuric acid and 1,1,3,3-tetramethyldisiloxane are added, and after reaction, the pH is adjusted to neutral to obtain a dihydrogen-terminated polysiloxane; Step B3: mixing and stirring the dihydrogen-terminated polysiloxane and DMF, adding chloroplatinic acid, reacting, adding 4-vinylbenzaldehyde, and continuing the reaction to obtain a modified polysiloxane, and mixing and reacting the modified polysiloxane, o-phenylenediamine, sodium pyrosulfite and DMF to obtain a strengthening agent; The amount ratio of 3-aminopropylmethyldiethoxysilane, maleic anhydride, triethylamine, acetic anhydride and nickel acetate in step B1 is 50mmol:50mmol:5mL:12mL:3.5g; The modified monomer, 3-mercaptopropylmethyldimethoxysilane, deionized water and 1,1,3,3-tetramethyldisiloxane described in step B2 are used in a ratio of 2 mmol:1 mmol:20 mL:1.5 mmol; The molar ratio of the dihydrogen-terminated polysiloxane to 4-vinylbenzaldehyde in step B3 is 1:2, and the amount ratio of the modified polysiloxane, o-phenylenediamine and sodium metabisulfite is 2.5 mmol:5 mmol:1 g.

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