Reinforced and toughened polypropylene plate and preparation method thereof

Abstract

The invention discloses a reinforced and toughened polypropylene plate and a preparation method thereof, and relates to the technical field of high polymer materials. The reinforced and toughened polypropylene plate prepared by the invention is prepared by the following steps: firstly, copolymerizing butene, long-chain olefin and 2-allyl furan to obtain a toughened elastomer; the preparation method comprises the following steps: respectively reacting brominated long-chain olefin with tri (4-bromophenyl) amine and carbazole to obtain an unsaturated heat stabilizer A and an unsaturated heat stabilizer B; then propylene, an unsaturated heat stabilizer A, an unsaturated heat stabilizer B and N-allylmaleimide are copolymerized to obtain modified polypropylene resin, finally, the modified polypropylene resin, a toughening elastomer, a stabilizer, a lubricant and an antioxidant are subjected to mixing and extrusion molding, and the reinforced and toughened polypropylene plate is obtained. The polypropylene plate prepared by the preparation method disclosed by the invention has the advantages of ageing resistance, tensile property and impact resistance.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, in particular to a reinforced and toughened polypropylene sheet and a preparation method thereof. Background Art

[0002] Polypropylene (PP) is widely used in packaging, automobiles, construction and other fields due to its excellent processability, chemical stability and economy. However, PP is brittle at low temperatures and has low impact strength, which limits its application in scenarios that require high toughness. PP's high crystallinity makes it brittle, and although it has strong rigidity, it exacerbates the brittleness problem.

[0003] Therefore, the introduction of elastomers has become a common strategy to improve the toughness of PP, among which polybutylene elastomer (PB-E) is favored due to its good compatibility with PP. PB-E can form stable microphase separation in PP, build a continuous network, effectively disperse external forces, and improve impact resistance. However, PB-E has poor compatibility with PP, which may weaken the tensile strength and impact toughness of the sheet.

[0004] Therefore, the applicant prepared a reinforced and toughened polypropylene sheet to solve the above problems. Summary of the invention

[0005] In order to solve the existing technical problems, the present invention provides a reinforced toughened polypropylene sheet, wherein the raw material components include, by weight: 50 parts by weight of modified polypropylene resin, 13 to 17 parts by weight of toughening elastomer, 8 parts by weight of stabilizer, 5 parts by weight of lubricant, and 1 to 2 parts by weight of antioxidant;

[0006] The modified polypropylene resin is obtained by copolymerizing propylene, unsaturated heat stabilizer A, unsaturated heat stabilizer B and N-allyl maleimide.

[0007] Furthermore, the toughened elastomer is obtained by copolymerization of butene, long-chain olefin and 2-allylfuran.

[0008] Furthermore, the unsaturated heat stabilizer A is obtained by reacting a brominated long-chain olefin with tri(4-bromophenyl)amine.

[0009] Furthermore, the unsaturated heat stabilizer B is obtained by reacting a brominated long-chain olefin with carbazole.

[0010] Furthermore, the long-chain olefin has at least 12 carbon atoms.

[0011] Furthermore, the stabilizer is zinc phosphate.

[0012] Furthermore, the lubricant is polyethylene wax.

[0013] Furthermore, the antioxidant is obtained by mixing antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2.

[0014] The present invention also provides a method for preparing a reinforced and toughened polypropylene sheet, and the preparation steps are as follows:

[0015] The modified polypropylene resin, toughened elastomer, stabilizer, lubricant and antioxidant are placed in a 60°C vacuum oven for drying for 12 to 14 hours; the modified polypropylene resin, toughened elastomer, stabilizer, lubricant and antioxidant are placed in a 60°C vacuum oven for drying for 12 to 14 hours, and then 50 parts by weight of the modified polypropylene resin, 12 to 14 parts by weight of the toughened elastomer, 8 parts by weight of the stabilizer, 5 parts by weight of the lubricant and 1 to 2 parts by weight of the antioxidant are added into a twin-screw mixer for mixing, the mixing temperature is 190°C, the twin-screw speed is 100 r / min, the melt blending is performed for 5 minutes, and then the pressurization is maintained at 0.5 MPa for 2 minutes and then directly extruded to obtain a reinforced toughened polypropylene sheet.

[0016] Further, the preparation method of the modified polypropylene resin is as follows:

[0017] The high pressure polymerization kettle is dried and then heated under vacuum at a mass ratio of 156 to 158:

[0018] 2.9~3.1:9.9~10.1:2.6~2.8:0.29~0.31 Toluene, unsaturated heat stabilizer A, unsaturated heat stabilizer B, N-allylmaleimide, triisobutylaluminum are added in sequence and stirred at 300~500rpm for 4~6min. After adding the hafnium dimethylpyridine imine complex and [Ph3C][B(C6F5)4], the molar ratio of the hafnium dimethylpyridine imine complex and [Ph3C][B(C6F5)4] is 1:2, wherein The mass of the hafnium dimethylpyridine imine complex is 0.0002 to 0.0004 times the mass of propylene. Propylene gas with a pressure of 5 atm is introduced and stirred at 550 rpm for 9 to 11 minutes at 50°C. The molar ratio of propylene to unsaturated thermal stabilizer B is 99:0.35. After depressurization, a 200-fold volumetric content of 2% hydrochloric acid in an ethanol solution is added to precipitate, filter, wash three times with ethanol, and then dry in a vacuum drying oven at 40°C to constant weight to obtain a modified polypropylene resin.

[0019] Furthermore, the preparation method of the unsaturated heat stabilizer A is as follows:

[0020] Under nitrogen protection, tri(4-bromophenyl)amine and potassium tert-butoxide were mixed at a mass ratio of 26 to 28:1, and then anhydrous tetrahydrofuran in an amount of 9 to 11 times the mass of tri(4-bromophenyl)amine was added and stirred until dissolved. The mixture was stirred continuously in a low-temperature tank at -78°C for 50 to 70 minutes, and then a 1.3M tert-butyl lithium hexane solution was added dropwise for 1.9 to 2.1 hours. The mass of the tert-butyl lithium hexane solution was 6 to 8 times the mass of tri(4-bromophenyl)amine. After stirring for 30 minutes, the mixture was heated to 0°C and stirred for 3 hours. , then add 18-bromo-1-octadecene after vacuum distillation in an amount of 1.1 to 1.3 times the mass of tri(4-bromophenyl)amine, continue stirring for 11 to 13 hours, then add 50 to 70 times the mass of saturated ammonium chloride solution to quench the reaction, perform extraction and separation, extract with ether three times, combine the organic phases and evaporate to remove the solvent, dry with anhydrous magnesium sulfate overnight, then filter to remove black oily solid impurities, perform silica gel column chromatography with n-hexane as the developing solvent, and obtain unsaturated thermal stabilizer A after vacuum distillation.

[0021] Furthermore, the preparation method of the unsaturated heat stabilizer B is as follows:

[0022] Under nitrogen protection, 9H-carbazole, a mineral oil suspension of 60% sodium hydride and anhydrous dimethylformamide are stirred at 25°C for 50-70 minutes in a mass ratio of 9:2.3:15-20, and then 18-bromo-1-octadecene which is 3-5 times the mass of 9H-carbazole and distilled under vacuum is added dropwise at a rate of 2-4s / drop, the mixture is heated to 80°C and refluxed with stirring for 1.9-2.1h, and then a saturated ammonium chloride solution with a mass of 50-70 times the mass of the 9H-carbazole is added to quench the reaction, and then extraction and separation are performed, and the organic phases are combined and the solvent is removed by rotary evaporation after extraction with dichloromethane for 3 times, and the mixture is dried over anhydrous magnesium sulfate overnight, and column chromatography is performed using n-hexane as a developing agent, and finally an unsaturated thermal stabilizer B is obtained by vacuum distillation.

[0023] Furthermore, the preparation method of the toughened elastomer is as follows:

[0024] The high-pressure polymerization autoclave is dried, and then toluene, 1-eicosene and 2-allylfuran are added in sequence in a mass ratio of 52-54:24-28:30-40 under vacuum conditions, the temperature is raised to 40°C, butene gas with a pressure of 0.1 MPa is introduced, the mass ratio of butene to 1-eicosene is 32-46:24-28, triisobutylaluminum, [Ph3C][B(C6F5)4] and dimethylpyridine imine hafnium complex are added in sequence in a molar ratio of 100:2:1, the mass of triisobutylaluminum is 0.0002-0.0004 times that of butene, the autoclave is stirred at 550 rpm for 9-11 minutes, the autoclave is vented and the pressure is released, a 2% hydrochloric acid ethanol solution with a volume content of 200 times the mass of propylene is added for precipitation, the autoclave is filtered, and the autoclave is dried in a vacuum oven to constant weight to obtain a toughened elastomer.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The reinforced and toughened polypropylene sheet prepared by the invention comprises the following steps: firstly, butene, long-chain olefin and 2-allylfuran are copolymerized to obtain a toughened elastomer; brominated long-chain olefin is reacted with tri(4-bromophenyl)amine and carbazole to obtain unsaturated heat stabilizer A and unsaturated heat stabilizer B respectively; propylene, unsaturated heat stabilizer A, unsaturated heat stabilizer B and N-allylmaleimide are copolymerized to obtain a modified polypropylene resin; and finally, the modified polypropylene resin, the toughened elastomer, a stabilizer, a lubricant and an antioxidant are mixed and extruded to obtain the reinforced and toughened polypropylene sheet. The polypropylene sheet prepared by the invention has good anti-aging performance, tensile resistance and impact resistance.

[0027] The present invention introduces furan into the toughened elastomer. The introduction of 2-allylfuran units changes the structure of the original single polybutene chain, forming a copolymer chain containing alternating or randomly distributed butene and furan units; the furan ring has high polarity and reactivity, and can promote the formation of stronger hydrogen bonds or other secondary interactions between molecules, thereby improving the cohesion and thermal stability of the toughened elastomer material; the presence of the furan ring increases the chemical resistance of the toughened elastomer material, and due to the special structure of the furan ring, the modified polybutene elastomer has improved tolerance to acids, alkalis, solvents and other corrosive chemicals.

[0028] The toughened elastomer of the present invention is obtained by copolymerization of long-chain olefins, and the impact strength and toughness of the toughened elastomer are improved by increasing the molecular weight, making the molecular weight distribution more uniform, reducing the crystallinity, and increasing the intermolecular interaction. It is subsequently mixed with a modified polypropylene resin to enhance its flexibility while causing the tensile strength of the modified polypropylene resin to be weakened.

[0029] The invention copolymerizes propylene, an unsaturated heat stabilizer A, an unsaturated heat stabilizer B and N-allyl maleimide to obtain a modified polypropylene resin. On the one hand, triphenylamine and carbazole groups having rigid groups with large conjugated structures are introduced into the modified polypropylene resin through the unsaturated heat stabilizer A and the unsaturated heat stabilizer B. The triphenylamine and carbazole groups themselves have excellent thermal stability and light stability. The thermal stability and light stability of the polypropylene can be improved by introducing the triphenylamine and carbazole groups into the polypropylene chain. On the other hand, tri(4-bromophenyl)amine of the unsaturated heat stabilizer A reacts with a brominated long-chain olefin to graft the long-chain olefin onto the triphenylamine, and then the triphenylamine and carbazole groups are grafted onto the triphenylamine. Triphenylamine with long-chain olefins is copolymerized with propylene, unsaturated heat stabilizer B, and N-allylmaleimide through unsaturated bonds to obtain a modified polypropylene resin with a hyperbranched structure. Maleimide groups are evenly distributed in the cavity of the modified polypropylene resin. When preparing a reinforced and toughened polypropylene sheet, the toughened elastomer penetrates into the cavity and cross-links with the modified polypropylene resin. At the same time, the furan groups on the surface of the toughened elastomer react with the maleimide groups on the surface of the cavity to undergo a Diels-Alder reaction, which further increases the cross-linking degree of the polypropylene sheet, thereby enhancing the flexibility of the polypropylene sheet and improving the tensile strength of the polypropylene sheet. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below in conjunction with examples, but the following examples should not be construed as limiting the present invention.

[0031] Some of the raw materials of the embodiments of the present invention and the comparative examples are as follows:

[0032] The hafnium dimethylpyridine imine complex was synthesized according to the method reported in the literature [Cai, ZG; Shigemasa, M.; Nakayama, Y.; Shiono, T. Catalytic synthesis of monodisperse polypropylene using a livingpolymerization system with ansa-fluorenylamidodimethyltitanium-based catalyst. Macromolecules, 2006, 39(19), 6321-6323.].

[0033] The stabilizer is zinc phosphate.

[0034] The lubricant is polyethylene wax.

[0035] The antioxidant is obtained by mixing antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2.

[0036] Example 1

[0037] A method for preparing a reinforced and toughened polypropylene sheet, the preparation steps are as follows:

[0038] The modified polypropylene resin, toughened elastomer, stabilizer, lubricant and antioxidant were placed in a 60°C vacuum oven for drying for 12 hours; the modified polypropylene resin, toughened elastomer, stabilizer, lubricant and antioxidant were placed in a 60°C vacuum oven for drying for 12 hours, and then 50 parts by weight of the modified polypropylene resin, 12 parts by weight of the toughened elastomer, 8 parts by weight of the stabilizer, 5 parts by weight of the lubricant and 1 part by weight of the antioxidant were added into a twin-screw mixer for mixing, the mixing temperature was 190°C, the twin-screw speed was 100r / min, the melt blending was performed for 5 minutes, and then the pressure was maintained at 0.5MPa for 2 minutes and then directly extruded to obtain a reinforced toughened polypropylene sheet;

[0039] The preparation method of the modified polypropylene resin is as follows: drying a high-pressure polymerization autoclave, then adding toluene, unsaturated heat stabilizer A, unsaturated heat stabilizer B, N-allylmaleimide, and triisobutylaluminum in a mass ratio of 156:2.9:9.9:2.6:0.29 in sequence under vacuum conditions, stirring at 300 rpm for 4 minutes, adding dimethylpyridine imine hafnium complex and [Ph3C][B(C6F5)4], and then adding dimethylpyridine imine hafnium complex and [Ph3C][B(C6F5)4] 4] is 1:2, wherein the mass of the hafnium dimethylpyridine imine complex is 0.0002 times the mass of propylene, propylene gas with a pressure of 5 atm is introduced and stirred at 550 rpm for 9 minutes at 50°C, the molar ratio of propylene to unsaturated thermal stabilizer B is 99:0.35, after depressurization, 200 times the mass of propylene and 2% hydrochloric acid in ethanol solution is added for precipitation, filtered, washed three times with ethanol, and then dried in a vacuum drying oven at 40°C to constant weight to obtain a modified polypropylene resin;

[0040] The preparation method of the unsaturated heat stabilizer A is as follows: under a nitrogen protection environment, tri(4-bromophenyl)amine and potassium tert-butoxide are mixed at a mass ratio of 26:1, and then anhydrous tetrahydrofuran with a mass of 9 times that of tri(4-bromophenyl)amine is added and stirred until dissolved, and the mixture is continuously stirred in a low-temperature tank at -78°C for 50 minutes, and then a 1.3M tert-butyl lithium hexane solution is added dropwise for 1.9 hours, and the mass of the tert-butyl lithium hexane solution is 6 times that of the tri(4-bromophenyl)amine. After continuing to stir for 30 minutes, the mixture is heated to 0°C and continued to stir. The reaction was stirred for 3 hours, and then 18-bromo-1-octadecene was added after vacuum distillation in an amount of 1.1 times the mass of tri(4-bromophenyl)amine, and the stirring was continued for 11 hours. After that, the mixture was added into a saturated ammonium chloride solution in an amount of 50 times the mass of the tri(4-bromophenyl)amine to quench the reaction, and then the mixture was extracted and separated, and the mixture was extracted with ether for 3 times. The organic phases were combined and the solvent was removed by rotary evaporation, and the mixture was dried over anhydrous magnesium sulfate overnight. Then, the mixture was filtered to remove black oily solid impurities, and silica gel column chromatography was performed using n-hexane as a developing solvent. After vacuum distillation, an unsaturated heat stabilizer A was obtained.

[0041] The preparation method of the unsaturated heat stabilizer B is as follows: under a nitrogen protection environment, 9H-carbazole, a mineral oil suspension of 60% sodium hydride, and anhydrous dimethylformamide are stirred at 25° C. for 50 minutes in a mass ratio of 9:2.3:15, and then 18-bromo-1-octadecene is added dropwise at a rate of 2s / drop at a rate of 3 times the mass of 9H-carbazole after vacuum decompression distillation, the temperature is raised to 80° C., refluxed and stirred for 1.9 hours, and then added to a saturated ammonium chloride solution with a mass of 50 times the mass of the 9H-carbazole to quench the reaction, extract and separate the liquids, extract with dichloromethane for 3 times, combine the organic phases, remove the solvent by rotary evaporation, dry with anhydrous magnesium sulfate overnight, perform column chromatography with n-hexane as a developing agent, and finally perform vacuum decompression distillation to obtain the unsaturated heat stabilizer B;

[0042] The preparation method of the toughened elastomer is as follows: drying a high-pressure polymerization autoclave, then sequentially adding toluene, 1-eicosene and 2-allylfuran in a mass ratio of 52:28:30 under vacuum conditions, heating to 40°C, introducing butene gas with a pressure of 0.1MPa, wherein the mass ratio of butene to 1-eicosene is 32:24, sequentially adding triisobutylaluminum, [Ph3C][B(C6F5)4] and dimethylpyridine imine hafnium complex in a molar ratio of 100:2:1, wherein the mass of triisobutylaluminum is 0.0002 times that of butene, stirring at 550rpm for 9min, exhausting the gas and releasing the pressure, adding an ethanol solution of hydrochloric acid with a volume content of 2% and a mass of 200 times that of propylene to precipitate, filtering, and drying in a vacuum oven to constant weight to obtain a toughened elastomer.

[0043] Example 2

[0044] A method for preparing a reinforced and toughened polypropylene sheet, the preparation steps are as follows:

[0045] The modified polypropylene resin, toughened elastomer, stabilizer, lubricant and antioxidant were placed in a 60°C vacuum oven for drying for 13 hours; the modified polypropylene resin, toughened elastomer, stabilizer, lubricant and antioxidant were placed in a 60°C vacuum oven for drying for 13 hours, and then 50 parts by weight of the modified polypropylene resin, 13 parts by weight of the toughened elastomer, 8 parts by weight of the stabilizer, 5 parts by weight of the lubricant and 1.5 parts by weight of the antioxidant were added into a twin-screw mixer for mixing, the mixing temperature was 190°C, the twin-screw speed was 100r / min, the melt blending was performed for 5 minutes, and then the pressure was maintained at 0.5MPa for 2 minutes and then directly extruded to obtain a reinforced toughened polypropylene sheet;

[0046] The preparation method of the modified polypropylene resin is as follows: drying a high-pressure polymerization autoclave, then sequentially adding toluene, unsaturated heat stabilizer A, unsaturated heat stabilizer B, N-allyl maleimide, and triisobutyl aluminum in a mass ratio of 157:3:10:2.7:0.3 under vacuum conditions, stirring at 400 rpm for 5 minutes, adding dimethylpyridine imine hafnium complex and [Ph3C][B(C6F5)4], and then adding dimethylpyridine imine hafnium complex and [Ph3C][B(C6F5)4] The molar ratio of the substance is 1:2, wherein the mass of the hafnium dimethylpyridine imine complex is 0.0003 times the mass of propylene, propylene gas with a pressure of 5 atm is introduced and stirred at 550 rpm for 10 minutes at 50°C, the molar ratio of propylene to the unsaturated thermal stabilizer B is 99:0.35, after the pressure is released, 200 times the mass of propylene and a 2% ethanol solution of hydrochloric acid is added to precipitate, filtered, washed three times with ethanol, and then dried in a vacuum drying oven at 40°C to constant weight to obtain a modified polypropylene resin;

[0047] The preparation method of the unsaturated heat stabilizer A is as follows: under a nitrogen protection environment, tri(4-bromophenyl)amine and potassium tert-butoxide are mixed at a mass ratio of 27:1, and then anhydrous tetrahydrofuran with a mass of 10 times that of tri(4-bromophenyl)amine is added and stirred until dissolved, and the mixture is continuously stirred in a low-temperature tank at -78°C for 60 minutes, and then a 1.3M tert-butyl lithium hexane solution is added dropwise for 2 hours, and the mass of the tert-butyl lithium hexane solution is 7 times that of the tri(4-bromophenyl)amine. After continuing to stir for 30 minutes, the mixture is heated to 0°C and continued to stir. The reaction was stirred for 3 hours, and then 18-bromo-1-octadecene was added after vacuum distillation in an amount of 1.2 times the mass of tri(4-bromophenyl)amine, and the stirring was continued for 12 hours. After that, the mixture was added into a saturated ammonium chloride solution in an amount of 60 times the mass of the tri(4-bromophenyl)amine to quench the reaction, and then the mixture was extracted and separated, and the mixture was extracted with ether for 3 times. The organic phases were combined and the solvent was removed by rotary evaporation, and the mixture was dried over anhydrous magnesium sulfate overnight. Then, the mixture was filtered to remove black oily solid impurities, and silica gel column chromatography was performed using n-hexane as a developing solvent. After vacuum distillation, an unsaturated heat stabilizer A was obtained.

[0048] The preparation method of the unsaturated heat stabilizer B is as follows: 9H-carbazole, a mineral oil suspension of 60% sodium hydride, and anhydrous dimethylformamide are stirred at 25° C. for 60 minutes in a nitrogen protection environment in a mass ratio of 9:2.3:18, and then 18-bromo-1-octadecene is added dropwise at a rate of 3s / drop at a rate of 3s / drop, the mixture is heated to 80° C. and refluxed and stirred for 2 hours, and then a saturated ammonium chloride solution with a mass of 60 times the mass of the 9H-carbazole is added to quench the reaction, and then extraction and separation are performed, and the organic phases are combined and the solvent is removed by rotary evaporation after extraction with dichloromethane for 3 times, and then the organic phases are dried overnight with anhydrous magnesium sulfate, and column chromatography is performed with n-hexane as a developing agent, and finally the unsaturated heat stabilizer B is obtained by vacuum decompression distillation;

[0049] The preparation method of the toughened elastomer is as follows: drying a high-pressure polymerization kettle, then adding toluene, 1-eicosene and 2-allylfuran in a mass ratio of 53:26:35 in sequence under vacuum conditions, heating to 40°C, introducing butene gas with a pressure of 0.1MPa, wherein the mass ratio of butene to 1-eicosene is 39:26, and sequentially adding triisobutylaluminum, [Ph3C][B(C6F5)4] and dimethylpyridine imine hafnium complex in a molar ratio of 100:2:1, wherein the mass of triisobutylaluminum is 0.0003 times that of butene, stirring at 550rpm for 10min, exhausting the gas and releasing the pressure, adding an ethanol solution of hydrochloric acid with a volume content of 2% and a mass of 200 times that of propylene to precipitate, filtering, and drying in a vacuum oven to constant weight to obtain a toughened elastomer.

[0050] Example 3

[0051] A method for preparing a reinforced and toughened polypropylene sheet, the preparation steps are as follows:

[0052] The modified polypropylene resin, toughened elastomer, stabilizer, lubricant and antioxidant were placed in a 60°C vacuum oven for drying for 14 hours; the modified polypropylene resin, toughened elastomer, stabilizer, lubricant and antioxidant were placed in a 60°C vacuum oven for drying for 14 hours, and then 50 parts by weight of the modified polypropylene resin, 14 parts by weight of the toughened elastomer, 8 parts by weight of the stabilizer, 5 parts by weight of the lubricant and 2 parts by weight of the antioxidant were added into a twin-screw mixer for mixing, the mixing temperature was 190°C, the twin-screw speed was 100r / min, the melt blending was performed for 5 minutes, and then the pressure was maintained at 0.5MPa for 2 minutes and then directly extruded to obtain a reinforced toughened polypropylene sheet;

[0053] The preparation method of the modified polypropylene resin is as follows: drying a high-pressure polymerization autoclave, then adding toluene, unsaturated heat stabilizer A, unsaturated heat stabilizer B, N-allylmaleimide, and triisobutylaluminum in a mass ratio of 158:3.1:10.1:2.8:0.31 in sequence under vacuum conditions, stirring at 500 rpm for 6 minutes, adding dimethylpyridine imine hafnium complex and [Ph3C][B(C6F5)4], and then adding dimethylpyridine imine hafnium complex and [Ph3C][B(C6F5)4] 4] is 1:2, wherein the mass of the hafnium dimethylpyridine imine complex is 0.0004 times the mass of propylene, propylene gas with a pressure of 5 atm is introduced and stirred at 550 rpm for 11 minutes at 50°C, the molar ratio of propylene to unsaturated thermal stabilizer B is 99:0.35, after depressurization, 200 times the mass of propylene and 2% hydrochloric acid in ethanol solution is added to precipitate, filtered, washed three times with ethanol, and then dried in a vacuum drying oven at 40°C to constant weight to obtain a modified polypropylene resin;

[0054] The preparation method of the unsaturated heat stabilizer A is as follows: under a nitrogen protection environment, tri(4-bromophenyl)amine and potassium tert-butoxide are mixed at a mass ratio of 28:1, and then anhydrous tetrahydrofuran with a mass of 11 times that of tri(4-bromophenyl)amine is added and stirred until dissolved, and the mixture is continuously stirred in a low-temperature tank at -78°C for 70 minutes, and then a 1.3M tert-butyl lithium hexane solution is added dropwise for 2.1 hours, and the mass of the tert-butyl lithium hexane solution is 8 times that of the tri(4-bromophenyl)amine. After continuing to stir for 30 minutes, the mixture is heated to 0°C, and then stirred for 30 minutes. The reaction was continued with stirring for 3 hours, and then 18-bromo-1-octadecene was added after vacuum distillation in an amount of 1.3 times the mass of tri(4-bromophenyl)amine, and the stirring was continued for 13 hours. Then, 70 times the mass of saturated ammonium chloride solution was added to quench the reaction, and then extraction and separation were performed. The organic phases were combined and the solvent was removed by rotary evaporation, and the organic phases were dried over anhydrous magnesium sulfate overnight, and then filtered to remove black oily solid impurities. Silica gel column chromatography was performed using n-hexane as a developing solvent, and unsaturated heat stabilizer A was obtained after vacuum distillation.

[0055] The preparation method of the unsaturated heat stabilizer B is as follows: 9H-carbazole, a mineral oil suspension of 60% sodium hydride, and anhydrous dimethylformamide are stirred at 25° C. for 70 minutes in a nitrogen protection environment in a mass ratio of 9:2.3:20, and then 18-bromo-1-octadecene is added dropwise at 4s / drop at a rate of 4s / drop, and the mixture is heated to 80° C. and refluxed and stirred for 2.1h, and then a saturated ammonium chloride solution with a mass of 70 times the mass of the 9H-carbazole is added to quench the reaction, and then extraction and separation are performed, and the organic phases are combined and the solvent is removed by rotary evaporation after extraction with dichloromethane for 3 times, and then the organic phases are dried overnight with anhydrous magnesium sulfate, and column chromatography is performed with n-hexane as a developing agent, and finally the unsaturated heat stabilizer B is obtained by vacuum decompression distillation;

[0056] The preparation method of the toughened elastomer is as follows: drying a high-pressure polymerization kettle, then adding toluene, 1-eicosene and 2-allylfuran in a mass ratio of 54:24:40 in sequence under vacuum conditions, heating to 40°C, introducing butene gas with a pressure of 0.1MPa, wherein the mass ratio of butene to 1-eicosene is 46:28, and sequentially adding triisobutylaluminum, [Ph3C][B(C6F5)4] and dimethylpyridine imine hafnium complex in a molar ratio of 100:2:1, wherein the mass of triisobutylaluminum is 0.0004 times that of butene, stirring at 550rpm for 11min, exhausting the gas and releasing the pressure, adding an ethanol solution of hydrochloric acid with a volume content of 2% and a mass of 200 times that of propylene to precipitate, filtering, and drying in a vacuum oven to constant weight to obtain a toughened elastomer.

[0057] Comparative Example 1

[0058] The difference between Comparative Example 1 and Example 2 is that only butene and 2-allylfuran are copolymerized to obtain the toughened elastomer; the remaining steps and components are the same as those in Example 2.

[0059] Comparative Example 2

[0060] The difference between Comparative Example 2 and Example 2 is that only butene and long-chain olefins are copolymerized to obtain the toughened elastomer; the remaining steps and components are the same as those in Example 2.

[0061] Comparative Example 3

[0062] The difference between Comparative Example 3 and Example 2 is that butene is copolymerized to obtain the toughened elastomer; the remaining steps and components are the same as those in Example 2.

[0063] Comparative Example 4

[0064] The difference between Comparative Example 4 and Example 2 is that propylene, unsaturated heat stabilizer B, and N-allylmaleimide are copolymerized to obtain modified polypropylene resin; the remaining steps and components are the same as those in Example 2.

[0065] Comparative Example 5

[0066] The difference between Comparative Example 5 and Example 2 is that propylene, unsaturated heat stabilizer A, and N-allylmaleimide are copolymerized to obtain modified polypropylene resin; the remaining steps and components are the same as those in Example 2.

[0067] Comparative Example 6

[0068] The difference between Comparative Example 6 and Example 2 is that propylene, unsaturated heat stabilizer A and unsaturated heat stabilizer B are copolymerized to obtain modified polypropylene resin; the remaining steps and components are the same as those in Example 2.

[0069] Effect example

[0070] Thermal oxidative aging performance: Take the same mass of reinforced and toughened polypropylene sheets prepared in the example and the comparative example, and carry out accelerated thermal oxidative aging treatment in the electric heating blast drying oven DHG-9070A. The aging temperature is selected as 90°C according to the melting point of the sample, the heating method is continuous heating, and the sample aging treatment time is: 168h;

[0071] The change rate of tensile strength of the reinforced and toughened polypropylene sheet before and after aging was tested, and the change rate of tensile strength = 100% * (tensile strength before aging - tensile strength after aging) / tensile strength before aging.

[0072] UV aging performance: The reinforced and toughened polypropylene sheets prepared in the embodiment and the comparative example of the same mass were taken and tested in the UV aging test box AtlasUVTest. The aging process was divided into a light stage and a dark stage. The light stage was 8 hours and the dark stage was 4 hours. The two stages were cyclically performed to simulate the natural aging process of the sample, wherein: the conditions of the light stage were: UV wavelength: 300-340nm; temperature: 60±3°C; irradiation intensity: 0.89kW / m2, dry; the conditions of the dark stage were: no UV irradiation; temperature: 50±3°C, condensation, and the sample aging treatment time was 168h respectively;

[0073] The change rate of tensile strength of the reinforced and toughened polypropylene sheet before and after aging was tested, and the change rate of tensile strength = 100% * (tensile strength before aging - tensile strength after aging) / tensile strength before aging.

[0074] Tensile strength and elongation at break: The reinforced and toughened polypropylene sheets prepared in the embodiment and the comparative example of the same mass were tested by a universal material testing machine INSTRON3367, USA at 25°C according to ISO527-1 standard, with a tensile rate of 20 mm / min. At least 5 specimens were tested for each group of materials to test their average tensile strength and elongation at break.

[0075] Impact strength: The same mass of the reinforced and toughened polypropylene sheets prepared in the embodiment and the comparative example were tested for impact strength in accordance with GB / T2546.2.

[0076] Table 1 below shows the test and analysis results of various properties of the reinforced and toughened polypropylene sheets prepared by Examples 1 to 3 of the present invention and Comparative Examples 1 to 6.

[0077] Table 1

[0078]

[0079] From Table 1, it can be found that the tensile strength, toughness, impact strength and aging resistance of the reinforced and toughened polypropylene sheet prepared in the embodiment are good; compared with Comparative Examples 1 to 3, it is found that the tensile strength, toughness, impact strength and thermal oxidative aging resistance of the reinforced and toughened polypropylene sheet prepared by copolymerizing butene, long-chain olefin and 2-allylfuran to obtain a toughened elastomer are good; compared with Comparative Examples 4 to 6, it is found that the tensile strength, toughness, impact strength, thermal oxidative aging resistance and UV aging resistance of the reinforced and toughened polypropylene sheet prepared by copolymerizing propylene, unsaturated heat stabilizer A, unsaturated heat stabilizer B and N-allylmaleimide to obtain a modified polypropylene resin are good.

[0080] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

Claims

1. A reinforced and toughened polypropylene sheet, characterized in that: The raw material components include, by weight: 50 parts by weight of modified polypropylene resin, 13 to 17 parts by weight of toughening elastomer, 8 parts by weight of stabilizer, 5 parts by weight of lubricant, and 1 to 2 parts by weight of antioxidant; the modified polypropylene resin is obtained by copolymerization of propylene, unsaturated heat stabilizer A, unsaturated heat stabilizer B, and N-allylmaleimide.

2. The reinforced and toughened polypropylene sheet according to claim 1, characterized in that: The toughened elastomer is obtained by copolymerizing butene, long-chain olefin and 2-allylfuran.

3. The reinforced and toughened polypropylene sheet according to claim 1, characterized in that: The unsaturated heat stabilizer A is obtained by reacting a brominated long-chain olefin with tri(4-bromophenyl)amine.

4. The reinforced and toughened polypropylene sheet according to claim 1, characterized in that: The unsaturated heat stabilizer B is obtained by reacting brominated long-chain olefin with carbazole.

5. The reinforced and toughened polypropylene sheet according to any one of claims 2 to 4, characterized in that: The long chain olefin has at least 12 carbon atoms.

6. A method for preparing a reinforced and toughened polypropylene sheet according to any one of claims 1 to 4, characterized in that: The method comprises the following preparation steps: The modified polypropylene resin, toughened elastomer, stabilizer, lubricant and antioxidant are placed in a 60°C vacuum oven for drying for 12 to 14 hours; the modified polypropylene resin, toughened elastomer, stabilizer, lubricant and antioxidant are placed in a 60°C vacuum oven for drying for 12 to 14 hours, and then 50 parts by weight of the modified polypropylene resin, 12 to 14 parts by weight of the toughened elastomer, 8 parts by weight of the stabilizer, 5 parts by weight of the lubricant and 1 to 2 parts by weight of the antioxidant are added into a twin-screw mixer for mixing, the mixing temperature is 190°C, the twin-screw speed is 100 r / min, the melt blending is performed for 5 minutes, and then the pressurization is maintained at 0.5 MPa for 2 minutes and then directly extruded to obtain a reinforced toughened polypropylene sheet.

7. The method for preparing the reinforced and toughened polypropylene sheet according to claim 6, characterized in that: The preparation method of the modified polypropylene resin is as follows: The high pressure polymerization kettle is dried and then heated under vacuum at a mass ratio of 156 to 158: 2.9~3.1:9.9~10.1:2.6~2.8:0.29~0.31 Toluene, unsaturated heat stabilizer A, unsaturated heat stabilizer B, N-allylmaleimide, triisobutylaluminum are added in sequence and stirred at 300~500rpm for 4~6min. After adding the hafnium dimethylpyridine imine complex and [Ph3C][B(C6F5)4], the molar ratio of the hafnium dimethylpyridine imine complex and [Ph3C][B(C6F5)4] is 1:2, wherein The mass of the hafnium dimethylpyridine imine complex is 0.0002 to 0.0004 times the mass of propylene. Propylene gas with a pressure of 5 atm is introduced and stirred at 550 rpm for 9 to 11 minutes at 50°C. The molar ratio of propylene to unsaturated thermal stabilizer B is 99:0.

35. After depressurization, a 200-fold volumetric content of 2% hydrochloric acid in an ethanol solution is added to precipitate, filter, wash three times with ethanol, and then dry in a vacuum drying oven at 40°C to constant weight to obtain a modified polypropylene resin.

8. The method for preparing the reinforced and toughened polypropylene sheet according to claim 7, characterized in that: The preparation method of the unsaturated heat stabilizer A is as follows: Under nitrogen protection, tri(4-bromophenyl)amine and potassium tert-butoxide were mixed at a mass ratio of 26 to 28:1, and then anhydrous tetrahydrofuran in an amount of 9 to 11 times the mass of tri(4-bromophenyl)amine was added and stirred until dissolved. The mixture was stirred continuously in a low-temperature tank at -78°C for 50 to 70 minutes, and then a 1.3M tert-butyl lithium hexane solution was added dropwise for 1.9 to 2.1 hours. The mass of the tert-butyl lithium hexane solution was 6 to 8 times the mass of tri(4-bromophenyl)amine. After stirring for 30 minutes, the mixture was heated to 0°C and stirred for 3 hours. , then add 18-bromo-1-octadecene after vacuum distillation in an amount of 1.1 to 1.3 times the mass of tri(4-bromophenyl)amine, continue stirring for 11 to 13 hours, then add 50 to 70 times the mass of saturated ammonium chloride solution to quench the reaction, perform extraction and separation, extract with ether three times, combine the organic phases and evaporate to remove the solvent, dry with anhydrous magnesium sulfate overnight, then filter to remove black oily solid impurities, perform silica gel column chromatography with n-hexane as the developing solvent, and obtain unsaturated thermal stabilizer A after vacuum distillation.

9. The method for preparing the reinforced and toughened polypropylene sheet according to claim 7, characterized in that: The preparation method of the unsaturated heat stabilizer B is as follows: Under nitrogen protection, 9H-carbazole, a mineral oil suspension of 60% sodium hydride and anhydrous dimethylformamide are stirred at 25°C for 50-70 minutes in a mass ratio of 9:2.3:15-20, and then 18-bromo-1-octadecene which is 3-5 times the mass of 9H-carbazole and distilled under vacuum is added dropwise at a rate of 2-4s / drop, the mixture is heated to 80°C and refluxed with stirring for 1.9-2.1h, and then a saturated ammonium chloride solution with a mass of 50-70 times the mass of the 9H-carbazole is added to quench the reaction, and then extraction and separation are performed, and the organic phases are combined and the solvent is removed by rotary evaporation after extraction with dichloromethane for 3 times, and the mixture is dried over anhydrous magnesium sulfate overnight, and column chromatography is performed using n-hexane as a developing agent, and finally an unsaturated thermal stabilizer B is obtained by vacuum distillation.

10. The method for preparing the reinforced and toughened polypropylene sheet according to claim 6, characterized in that: The preparation method of the toughened elastomer is as follows: The high-pressure polymerization autoclave is dried, and then toluene, 1-eicosene and 2-allylfuran are added in sequence in a mass ratio of 52-54:24-28:30-40 under vacuum conditions, the temperature is raised to 40°C, butene gas with a pressure of 0.1 MPa is introduced, the mass ratio of butene to 1-eicosene is 32-46:24-28, triisobutylaluminum, [Ph3C][B(C6F5)4] and dimethylpyridine imine hafnium complex are added in sequence in a molar ratio of 100:2:1, the mass of triisobutylaluminum is 0.0002-0.0004 times that of butene, the autoclave is stirred at 550 rpm for 9-11 minutes, the autoclave is vented and the pressure is released, a 2% hydrochloric acid ethanol solution with a volume content of 200 times the mass of propylene is added for precipitation, the autoclave is filtered, and the autoclave is dried in a vacuum oven to constant weight to obtain a toughened elastomer.

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