Nanofilled reinforced high efficiency flame retardant polypropylene material and its preparation method

Abstract

The application discloses a kind of nano filling enhanced high-efficiency flame-retardant polypropylene material and preparation method thereof, and relates to the technical field of polypropylene material.The material includes, by weight parts: polypropylene 100 parts, flame-retardant silica sol 20-30 parts, dicumyl peroxide 0.5-1 part, modified zinc oxide whisker 10-15 parts, masterbatch A 50-60 parts, maleic anhydride grafted polypropylene 10-20 parts, nano filler 10-15 parts, vinyltrimethoxysilane 1-5 parts.The flame-retardant silica sol used in the application is modified by magnesium olivine acidolysis and boric acid / phytic acid, realizes B / P element doping, and then grafted with double bond by silane hydrolysis solution to form interface compatible flame retardant.The polypropylene composite material prepared by the application has excellent mechanical properties, flame retardance and impact resistance, and low content of volatile organic compounds and aldehyde ketone substances, meeting environmental protection requirements.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of polypropylene materials, in particular to a nano-filled and reinforced high-efficiency flame-retardant polypropylene material and a preparation method thereof. BACKGROUND

[0002] Polypropylene (PP) is widely used in automotive parts, electronic appliances, building materials and other fields due to its excellent processing performance, chemical stability and low cost. However, the limiting oxygen index (LOI) of polypropylene is only 17-18%, which belongs to flammable materials, and the melt dripping phenomenon is serious during combustion, which exists a major fire hazard. With the increasing demand for comprehensive performance of materials, it is an urgent need to develop polypropylene composites with high-efficiency flame retardancy, excellent mechanical properties and environmental friendliness.

[0003] Traditional halogen-based flame retardants (such as decabromodiphenyl ether) have high flame retardant efficiency, but release toxic gases such as dioxins during combustion, and have been gradually banned. Halogen-free flame retardants (such as aluminum hydroxide, expanded graphite) require high addition amount (> 30wt%) to achieve V-0 level, which seriously deteriorates the tensile strength (< 35MPa) and impact toughness (< 10KJ / m 2 ). Bio-based flame retardants (such as phytic acid, chitosan) are environmentally friendly but have poor heat resistance and are easily decomposed during high-temperature processing; the release amount of volatile organic compounds and aldehyde ketone compounds is difficult to meet the standards of high-end fields such as automotive interiors.

[0004] Nanofillers (such as silicon dioxide, carbon nanotubes) are prone to agglomeration, which leads to stress concentration and reduces the toughness of the material; when the surface modification is insufficient, the interface compatibility between the nanoparticles and the polypropylene matrix is poor, which restricts the strength improvement effect. The existing technology attempts to improve the performance by compounding the flame retardant system or surface modifying the nanoparticles, but the compatibility between the flame retardant and the matrix is insufficient, and the long-term use is prone to migration and precipitation; the bending strength is generally lower than 60MPa, and the anti-scratch performance is poor; in addition, it is difficult to achieve high oxygen index (> 30%) and high impact strength (> 14KJ / m 2 ). SUMMARY

[0005] The present application aims to provide a nano-filled and reinforced high-efficiency flame-retardant polypropylene material and a preparation method thereof to solve the problems in the prior art.

[0006] To solve the above technical problems, the present application provides the following technical scheme: a nano-filled and reinforced high-efficiency flame-retardant polypropylene material, by weight, comprising 100 parts of polypropylene, 20-30 parts of flame-retardant silica sol, 0.5-1 part of dicumyl peroxide, 10-15 parts of modified zinc oxide whisker, 50-60 parts of masterbatch A, 10-20 parts of maleic anhydride grafted polypropylene, 10-15 parts of nanofiller, and 1-5 parts of vinyltrimethoxysilane.

[0007] The preparation method of the fire-retardant silica sol is as follows: magnesium olivine is crushed to 300 mesh, dispersed in water, and stirred to obtain a dispersion liquid by using a homogenizer, then boric acid and phytic acid are added, stirred uniformly, and then stirred at 80-90 DEG C for 1h, then 0.3-0.6 times the mass of the dispersion liquid of a silane hydrolysis solution is added within 30 min, after the addition, the stirring is continued for 1h, and then the product is aged for 12-48h, and then concentrated by atmospheric distillation to obtain a fire-retardant silica sol with a solid content of 50%;

[0008] The nano filler is composed of cerium oxide with a particle size of 50-200nm and zinc borate with a particle size of 100-400nm at a mass ratio of 1-5:1.

[0009] Further, the masterbatch A is prepared by blending and extruding polystyrene, polypropylene and styrene-butadiene-styrene triblock copolymer at a mass ratio of 30-45:10-20:5-10.

[0010] Further, the magnesium olivine is waste magnesium olivine powder or commercially available magnesium olivine powder, and the main chemical components and their contents of the magnesium olivine are as follows: the content of MgO is 38-47wt%, the content of SiO2 is 39-44wt%, and the content of Fe2O3 is 7-11wt%.

[0011] Further, the modified zinc oxide whisker is prepared by coupling agent modification.

[0012] Further, the zinc oxide whisker is a four-needle zinc oxide whisker needle body, the length is about 15-25μm, the bottom diameter is about 1.5-3.5μm, and the tip diameter is about 300-500nm.

[0013] Further, the mass ratio of the dispersion liquid to boric acid and phytic acid is 1:1-2:0.2-1.

[0014] Further, the silane hydrolysis solution comprises vinyltrimethoxysilane 5-30g / L, ethanol 5-40g / L, and deionized water in a residual amount, and the pH of the silane hydrolysis solution is adjusted to 3-3.5 by hydrochloric acid.

[0015] Further, the concentration of boric acid is 5-15g / L.

[0016] Further, the concentration of phytic acid is 5-15g / L.

[0017] Further, the concentration of the dispersion liquid is 1-10g / L.

[0018] The application also provides a preparation method of the nano-filled and reinforced high-efficiency fire-retardant polypropylene material.

[0019] Take 100 parts of polypropylene by weight and heat to a molten state, add 20-30 parts of flame-retardant silica sol, 0.5-1 part of dicumyl peroxide, 10-15 parts of modified zinc oxide whisker, melt blend for 70 minutes at 30 rpm, then add 50-60 parts of masterbatch A, 10-20 parts of maleic anhydride grafted polypropylene, 10-15 parts of nano filler, 1-5 parts of vinyl trimethoxysilane, extrude and granulate at 180°C to obtain a polypropylene material.

[0020] Further, the polypropylene is B8101, with a density of 0.9 g / cm³ and a shrinkage of 1.3-1.7%, produced by Qingchuan Plastic Co., Ltd. of Dongguan.

[0021] Further, the polystyrene is GPPS123P, produced by Sike.

[0022] Further, the grafting rate of the maleic anhydride grafted polypropylene is 0.8-1.0%, and the melt index is 80-120 g / 10 min.

[0023] Further, the number average molecular weight of the styrene-butadiene-styrene triblock copolymer ranges from 1000 to 30000, and the mass fraction of 1,2-butadiene contained therein is 20-80%.

[0024] Compared with the prior art, the present application has the following beneficial effects:

[0025] (1) The present application selects a high proportion of polystyrene as masterbatch A, and adjusts the proportion relationship between it and polypropylene masterbatch B to improve the rigidity and strength of the polypropylene material while ensuring the toughness of the polypropylene matrix.

[0026] (2) The present application selects forsterite as the raw material of the flame-retardant sol, and forsterite releases Mg and Fe atoms in an acidic medium, which are then converted into silica sol. The acidic medium of the present application uses boric acid and phytic acid, which can dissolve Mg atoms while reacting with Si-OH in the structure of the silica sol to modify the sol, achieve B and P element doping, and synergize with the silica sol to greatly improve the flame-retardant effect of the sol, thereby making the polypropylene material have excellent flame-retardant properties. In addition, vinyl silane is added during preparation to introduce double bonds into the molecular chain of the silica sol, which can be chemically bonded to the polypropylene molecular chain during the melt blending and extrusion stage, achieving good interfacial compatibility and thus imparting the polypropylene material with more stable flame-retardant effect.

[0027] (3) The polypropylene composite material prepared by the application has good mechanical properties, and also has good flame retardation and impact resistance. Moreover, the polypropylene composite material has low content of volatile organic compounds and aldehyde ketone compounds, can well meet the increasingly improved environmental protection demand at present, and meets the demand of environmental protection and sustainable development.

[0028] (4) Compared with single use, the application of the compounded nano inorganic filler into the system is optimal for improving the strength, impact resistance and flame retardation. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the application.

[0030] Example 1; (1) The forsterite is crushed to 300 mesh, dispersed in water with a concentration of 1 g / L, and a homogenizer is used for stirring to obtain a dispersion liquid, then 5 g / L of boric acid and 5 g / L of phytic acid are added, the mass ratio of the dispersion liquid to boric acid and phytic acid is 1:1:0.2, after uniform stirring, stirring is carried out at 90 DEG C and 100 rpm for 1 h, then 0.3 times the mass of the dispersion liquid of the silane hydrolysis liquid is added within 30 min, the silane hydrolysis liquid includes 30 g / L of vinyl trimethoxysilane, 40 g / L of ethanol and the balance of deionized water, and hydrochloric acid is used to adjust the pH of the silane hydrolysis liquid to 3, after the addition is completed, the stirring is continued for 1 h, and the aging is carried out for 24 h, and the normal pressure distillation concentration is carried out to obtain a flame-retardant silica sol with a solid content of 50%;

[0031] (2) Polystyrene, polypropylene and styrene-butadiene-styrene triblock copolymer are blended and extruded at a mass ratio of 30:10:5, the temperature is set to 180-240 DEG C, and the screw rotation speed is 50-60 rpm to obtain a masterbatch A;

[0032] (3) 20 g of anhydrous ethanol, 3 g of deionized water and 2 g of vinyl trimethoxysilane are mixed, hydrochloric acid is used to adjust the pH value to 2, and the mixture is placed at room temperature for 1 h to obtain a modified reagent; 30 g of dried zinc oxide whiskers and 20 g of anhydrous ethanol are dispersed in a beaker for 1 h, the modified reagent is added, and constant temperature 70 DEG C water bath stirring is carried out for 60 min, then filtration and drying are carried out to obtain modified zinc oxide whiskers;

[0033] (4) 100 parts of polypropylene is heated to melt state, then 20 parts of flame-retardant silica sol, 0.5 parts of dicumyl peroxide, 10 parts of modified zinc oxide whisker are melt blended at 30 rpm for 70 minutes, then 50 parts of masterbatch A, 10 parts of maleic anhydride grafted polypropylene, 10 parts of nano filler, 1 part of vinyl trimethoxysilane are extruded and granulated to obtain the polypropylene material; the nano filler is composed of cerium oxide with a particle size of 50 nm and zinc borate with a particle size of 100 nm at a mass ratio of 1:1.

[0034] Example 2; (1) Forsterite is crushed to 300 mesh, dispersed in water with a concentration of 1 g / L, and a homogenizer is used to stir to obtain a dispersion liquid, then 5 g / L of boric acid and 5 g / L of phytic acid are added, the mass ratio of the dispersion liquid to boric acid and phytic acid is 1:1:0.2, after stirring uniformly, stirring is carried out at 90°C and 100 rpm for 1 h, then 0.3 times the mass of the dispersion liquid is added in 30 min. Silane hydrolysis liquid, the silane hydrolysis liquid contains 30 g / L of vinyl trimethoxysilane, 40 g / L of ethanol, and deionized water in a residual amount, and hydrochloric acid is used to adjust the pH of the silane hydrolysis liquid to 3, after addition, stirring is continued for 1 h, and aging is carried out for 24 h, and then normal pressure distillation concentration is carried out to obtain a flame-retardant silica sol with a solid content of 50%;

[0035] (2) Polystyrene, polypropylene, and styrene-butadiene-styrene triblock copolymer are blended and extruded at a mass ratio of 30:20:5, the temperature is set to 180-240°C, and the screw rotation speed is 50-60 rpm to obtain masterbatch A;

[0036] (3) 20 g of anhydrous ethanol, 3 g of deionized water, and 2 g of vinyl trimethoxysilane are mixed, the pH value is adjusted to 2 with hydrochloric acid, and the mixture is left to stand at room temperature for 1 h to obtain a modified reagent; 30 g of dried zinc oxide whisker and 20 g of anhydrous ethanol are dispersed in a beaker for 1 h, the modified reagent is added, and constant-temperature 70°C water bath stirring is carried out for 60 min, then suction filtration and drying are carried out to obtain modified zinc oxide whisker;

[0037] (4) 100 parts of polypropylene is heated to melt state, then 20 parts of flame-retardant silica sol, 0.5 parts of dicumyl peroxide, 10 parts of modified zinc oxide whisker are melt blended at 30 rpm for 70 minutes, then 50 parts of masterbatch A, 10 parts of maleic anhydride grafted polypropylene, 10 parts of nano filler, 1 part of vinyl trimethoxysilane are extruded and granulated to obtain the polypropylene material; the nano filler is composed of cerium oxide with a particle size of 50 nm and zinc borate with a particle size of 100 nm at a mass ratio of 1:1.

[0038] Example 3; (1) The forsterite is crushed to 300 mesh, dispersed in water with a concentration of 3.2 g / L, and stirred with a homogenizer to obtain a dispersion liquid, then 7.5 g / L boric acid and 7.5 g / L phytic acid are added, the mass ratio of the dispersion liquid to boric acid and phytic acid is 1:1.5:0.4, after stirring uniformly, stirring at 90℃, 100 rpm for 1h, then 0.4 times the mass of the dispersion liquid of silane hydrolysis liquid is added within 30 min, the silane hydrolysis liquid includes 11 g / L of vinyl trimethoxysilane, 40 g / L of ethanol, and the balance of deionized water, and the pH of the silane hydrolysis liquid is adjusted to 3 with hydrochloric acid, after adding, continue to stir for 1h, age for 24h, and concentrate under normal pressure distillation to obtain a flame-retardant silica sol with a solid content of 50%;

[0039] (2) The polystyrene, polypropylene, and styrene-butadiene-styrene triblock copolymer are blended and extruded at a mass ratio of 34:10:5.7, the temperature is set to 180-240℃, and the screw rotation speed is 50-60 rpm to obtain a masterbatch A;

[0040] (3) 27.5 g of anhydrous ethanol, 4.7 g of deionized water, and 4 g of vinyl trimethoxysilane are mixed, the pH value is adjusted to 2 with hydrochloric acid, and the mixture is left to stand at room temperature for 1h to obtain a modified reagent; 35 g of dried zinc oxide whiskers and 30 g of anhydrous ethanol are dispersed in a beaker for 1h, the modified reagent is added, and constant temperature 70℃ water bath stirring is carried out for 60 min, then filtration and drying are carried out to obtain modified zinc oxide whiskers;

[0041] (4) According to the weight fraction, 100 parts of polypropylene is heated to a molten state, 22 parts of flame-retardant silica sol, 0.5 parts of dicumyl peroxide, 15 parts of modified zinc oxide whiskers are added, and melt blending is carried out at 30 rpm for 70 minutes, then 55 parts of masterbatch A, 12 parts of maleic anhydride grafted polypropylene, 11 parts of nano filler, and 1 part of vinyl trimethoxysilane are added to extrude and granulate to obtain a polypropylene material; the nano filler is composed of cerium oxide with a particle size of 60 nm and zinc borate with a particle size of 200 nm at a mass ratio of 2:1.

[0042] Example 4; (1) The forsterite is crushed to 300 mesh, dispersed in water with a concentration of 3.2 g / L, and stirred with a homogenizer to obtain a dispersion liquid, then 7.5 g / L boric acid and 7.5 g / L phytic acid are added, the mass ratio of the dispersion liquid to boric acid and phytic acid is 1:1.5:0.4, after stirring uniformly, stirring at 90℃, 100 rpm for 1h, then 0.4 times the mass of the dispersion liquid of silane hydrolysis liquid is added within 30 min, the silane hydrolysis liquid includes 11 g / L of vinyl trimethoxysilane, 40 g / L of ethanol, and the balance of deionized water, and the pH of the silane hydrolysis liquid is adjusted to 3 with hydrochloric acid, after adding, continue to stir for 1h, age for 24h, and concentrate under normal pressure distillation to obtain a flame-retardant silica sol with a solid content of 50%;

[0043] (2) Polystyrene, polypropylene, styrene-butadiene-styrene triblock copolymer were blended and extruded at a mass ratio of 30:10:5, the temperature was set at 180-240℃, and the screw rotation speed was 50-60 rpm, to obtain a masterbatch A;

[0044] (3) 27.5 g of anhydrous ethanol, 4.7 g of deionized water, and 4 g of vinyltrimethoxysilane were mixed, and the pH value was adjusted to 2 with hydrochloric acid. The mixture was left to stand at room temperature for 1 h to obtain a modified reagent. 35 g of dried zinc oxide whiskers and 30 g of anhydrous ethanol were dispersed in a beaker for 1 h, and the modified reagent was added. The mixture was stirred in a constant-temperature 70℃ water bath for 60 min, and then was suction filtered and dried to obtain modified zinc oxide whiskers;

[0045] (4) 100 parts of polypropylene was heated to a molten state, and then 23 parts of a flame-retardant silica sol, 0.5 parts of dicumyl peroxide, 12 parts of modified zinc oxide whiskers were added and melt blended at 30 rpm for 70 min. Then 50 parts of masterbatch A, 10 parts of maleic anhydride grafted polypropylene, 15 parts of nano filler, and 3 parts of vinyltrimethoxysilane were added and extruded to obtain a polypropylene material. The nano filler was composed of cerium oxide with a particle size of 60 nm and zinc borate with a particle size of 200 nm at a mass ratio of 2:1.

[0046] Example 5: (1) Forsterite powder was crushed to 300 mesh and dispersed in water at a concentration of 7 g / L. A dispersing solution was obtained by stirring with a homogenizer. Then, boric acid with a concentration of 11 g / L and phytic acid with a concentration of 5 g / L were added. The mass ratio of the dispersing solution to boric acid and phytic acid was 1:1.5:0.8. After stirring uniformly, the mixture was stirred at 90℃ and 100 rpm for 1 h. Then, a silane hydrolysis solution with a volume of 0.5 times that of the dispersing solution was added within 30 min. The silane hydrolysis solution contained 21 g / L of vinyltrimethoxysilane, 40 g / L of ethanol, and the rest deionized water. The pH of the silane hydrolysis solution was adjusted to 3.5 with hydrochloric acid. After the addition was completed, the mixture was continuously stirred for 1 h. After aging for 24 h, the mixture was concentrated by atmospheric distillation to obtain a flame-retardant silica sol with a solid content of 50%;

[0047] (2) Polystyrene, polypropylene, styrene-butadiene-styrene triblock copolymer were blended and extruded at a mass ratio of 38:15:7.5, the temperature was set at 180-240℃, and the screw rotation speed was 50-60 rpm, to obtain a masterbatch A;

[0048] (3) 40 g of anhydrous ethanol, 7.6 g of deionized water, and 7.3 g of vinyltrimethoxysilane were mixed, and the pH value was adjusted to 3 with hydrochloric acid. The mixture was left to stand at room temperature for 2 h to obtain a modified reagent. 43 g of dried zinc oxide whiskers and 47 g of anhydrous ethanol were dispersed in a beaker for 2 h, and the modified reagent was added. The mixture was stirred in a constant-temperature 70℃ water bath for 60 min, and then was suction filtered and dried to obtain modified zinc oxide whiskers;

[0049] (4) take 100 parts of polypropylene to melt state, add 26 parts of flame retardant silica sol, 0.8 parts of dicumyl peroxide, 13 parts of modified zinc oxide whisker melt blend at 30 rpm for 70 minutes, then add 55 parts of masterbatch A, 15 parts of maleic anhydride grafted polypropylene, 10 parts of nano filler, 3 parts of vinyl trimethoxysilane extrusion granulation, polypropylene material is obtained; the nano filler is composed of cerium oxide with a particle size of 120 nm and zinc borate with a particle size of 300 nm in a mass ratio of 3:1.

[0050] Example 6; (1) Forsterite is crushed to 300 mesh, dispersed in water with a concentration of 7 g / L, and a homogenizer is used to stir to obtain a dispersion, then add boric acid with a concentration of 11 g / L and phytic acid with a concentration of 5 g / L, the mass ratio of dispersion to boric acid and phytic acid is 1:1.5:0.8, after stirring uniformly, stirring at 90℃, 100 rpm for 1h, then add 0.5 times of silane hydrolysis liquid of the dispersion within 30 min, the silane hydrolysis liquid includes vinyl trimethoxysilane 21 g / L, ethanol 40 g / L, deionized water in residual amount, and hydrochloric acid is used to adjust the pH of the silane hydrolysis liquid to 3.5, after adding, continue to stir for 1h, age for 24h, and concentrate by atmospheric distillation to obtain a flame retardant silica sol with a solid content of 50%;

[0051] (2) Blend and extrude polystyrene, polypropylene, and styrene-butadiene-styrene triblock copolymer in a mass ratio of 40:17:10, set the temperature to 180-240℃, and the screw rotation speed to 50-60 rpm to obtain masterbatch A;

[0052] (3) Mix 40g of anhydrous ethanol, 7.6g of deionized water, and 7.3g of vinyl trimethoxysilane, adjust the pH value to 3 with hydrochloric acid, and stand at room temperature for 2h to obtain a modified reagent; disperse 43g of dried zinc oxide whisker and 47g of anhydrous ethanol in a beaker for 2h, add the modified reagent, stir in a constant temperature 70℃ water bath for 60min, then filter and dry to obtain modified zinc oxide whisker;

[0053] (4) take 100 parts of polypropylene to melt state, add 26 parts of flame retardant silica sol, 0.8 parts of dicumyl peroxide, 13 parts of modified zinc oxide whisker melt blend at 30 rpm for 70 minutes, then add 55 parts of masterbatch A, 15 parts of maleic anhydride grafted polypropylene, 10 parts of nano filler, 3 parts of vinyl trimethoxysilane extrusion granulation, polypropylene material is obtained; the nano filler is composed of cerium oxide with a particle size of 120 nm and zinc borate with a particle size of 300 nm in a mass ratio of 3:1.

[0054] Example 7; (1) The forsterite was crushed to 300 mesh, dispersed in water at a concentration of 7 g / L, and stirred with a homogenizer to obtain a dispersion, then boric acid at a concentration of 11 g / L and phytic acid at a concentration of 10 g / L were added, the mass ratio of the dispersion to boric acid and phytic acid was 1:1.5:0.8, after stirring uniformly, stirring was carried out at 90°C and 100 rpm for 1 h, then a silane hydrolysis solution with a mass of 0.5 times that of the dispersion was added within 30 min, the silane hydrolysis solution included vinyltrimethoxysilane 21 g / L, ethanol 40 g / L, and deionized water in a residual amount, and hydrochloric acid was used to adjust the pH of the silane hydrolysis solution to 3.5, after addition, stirring was continued for 1 h, aging was carried out for 24 h, and normal pressure distillation concentration was carried out to obtain a fire-retardant silica sol with a solid content of 50%;

[0055] (2) Polystyrene, polypropylene, and styrene-butadiene-styrene triblock copolymer were blended and extruded at a mass ratio of 45:10:10, the temperature was set to 180-240°C, and the screw rotation speed was 50-60 rpm to obtain a masterbatch A;

[0056] (3) 40 g of anhydrous ethanol, 7.6 g of deionized water, and 7.3 g of vinyltrimethoxysilane were mixed, hydrochloric acid was used to adjust the pH value to 3, and standing was carried out at room temperature for 2 h to obtain a modified reagent; 43 g of dried zinc oxide whiskers and 47 g of anhydrous ethanol were dispersed in a beaker for 2 h, the modified reagent was added, constant-temperature 70°C water bath stirring was carried out for 60 min, then filtration and drying were carried out to obtain modified zinc oxide whiskers;

[0057] (4) 100 parts of polypropylene were heated to a molten state, 30 parts of the fire-retardant silica sol, 1 part of dicumyl peroxide, and 12 parts of the modified zinc oxide whiskers were added, and melt blending was carried out at 30 rpm for 70 min, then 58 parts of the masterbatch A, 15 parts of maleic anhydride grafted polypropylene, 15 parts of a nano filler, and 5 parts of vinyltrimethoxysilane were added, and extrusion granulation was carried out to obtain a polypropylene material; the nano filler was composed of cerium oxide with a particle size of 120 nm and zinc borate with a particle size of 300 nm at a mass ratio of 3:1.

[0058] Comparative Example 1; the difference between Comparative Example 1 and Example 3 was that no boric acid was added in the preparation of the fire-retardant silica sol, the concentration of phytic acid was adjusted to 15 g / L, and the other steps were the same as in Example 3.

[0059] Comparative Example 2; the difference between Comparative Example 2 and Example 3 was that no phytic acid was added in the preparation of the fire-retardant silica sol, the concentration of boric acid was adjusted to 15 g / L, and the other steps were the same as in Example 3.

[0060] Comparative Example 3; the difference between Comparative Example 3 and Example 3 was that no silane hydrolysis solution was added in the preparation of the fire-retardant silica sol, and the other steps were the same as in Example 3.

[0061] Comparative Example 4; Comparative Example 4 differs from Example 3 in that the flame-retardant silica sol is concentrated to a solid content of 20%, and the remaining steps are the same as Example 3.

[0062] Comparative Example 5; Comparative Example 5 differs from Example 3 in that no masterbatch A is added, and the remaining steps are the same as Example 3.

[0063] Comparative Example 6; Comparative Example 6 differs from Example 3 in that no modified zinc oxide whisker is added, and the remaining steps are the same as Example 3.

[0064] Comparative Example 7; Comparative Example 7 differs from Example 3 in that no zinc borate is added, and the remaining steps are the same as Example 3.

[0065] Comparative Example 8; Comparative Example 8 differs from Example 3 in that no cerium oxide is added, and the remaining steps are the same as Example 3.

[0066] Performance test

[0067] (1) Flame-retardant performance: test according to the test standard provided by UL-94, sample size is 125x13x3.0mm;

[0068] (2) Tensile strength: test according to ISO527-2-2016, tensile speed is 50mm / min;

[0069] (3) Bending strength: test according to the standard provided by ISO178;

[0070] (4) Notched impact strength: test according to standard ISO180-2000, test temperature is 23℃;

[0071] (5) Oxygen index: test according to GB / T2406.2-2009 Oxygen Index Method-Plastics Burning Performance Test Method.

[0072] The polypropylene materials provided by Examples 1-7 and Comparative Examples 1-8 are tested according to the above test methods, and the test results are shown in Table 1:

[0073]

[0074] It is obvious to those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, the examples should be considered as exemplary and non-limiting, and the scope of the present application is defined by the appended claims rather than the above description, and therefore all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application. Any mark in the claims should not be considered as limiting the involved claims.

Claims

1. A nanofilled reinforced high efficiency flame retardant polypropylene material, characterized in that, The polypropylene material comprises 100 parts of polypropylene, 20-30 parts of the flame-retardant silica sol, 0.5-1 part of dicumyl peroxide, 10-15 parts of modified zinc oxide whiskers, 50-60 parts of the masterbatch A, 10-20 parts of maleic anhydride grafted polypropylene, 10-15 parts of the nano filler, and 1-5 parts of vinyltrimethoxysilane. The preparation method of the flame-retardant silica sol comprises the following steps: crushing forsterite to 300 mesh, dispersing in water, stirring to obtain a dispersion liquid by using a homogenizer, then adding boric acid and phytic acid, stirring uniformly, stirring at 80-90℃ for 1h, then adding a silane hydrolysis liquid with a mass of 0.3-0.6 times of the dispersion liquid within 30 min, continuing to stir for 1h, aging for 12h-48h, and concentrating by normal pressure distillation to obtain the flame-retardant silica sol with a solid content of 50%. The nano filler is composed of cerium oxide and zinc borate with a mass ratio of 1-5:

1. The masterbatch A is prepared by blending and extruding polystyrene, polypropylene and styrene-butadiene-styrene triblock copolymer with a mass ratio of 30-45:10-20:5-10.

2. A nanofilled reinforced high efficiency flame retardant polypropylene material as claimed in claim 1, wherein, The particle size of the cerium oxide is 50-200nm, and the particle size of the zinc borate is 100-400nm.

3. The nanofilled reinforced high efficiency flame retardant polypropylene material according to claim 1, characterized in that, The modified zinc oxide whiskers are prepared by coupling agent modification.

4. The nanofilled reinforced high efficiency flame retardant polypropylene material according to claim 1, characterized in that, The mass ratio of the dispersion liquid to boric acid and phytic acid is 1:1-2:0.2-1.

5. The nanofilled reinforced high efficiency flame retardant polypropylene material according to claim 1, wherein, The silane hydrolysis liquid comprises vinyltrimethoxysilane 5-30g / L, ethanol 5-40g / L, and deionized water in a residual amount, and the pH of the silane hydrolysis liquid is adjusted to 3-3.5 by hydrochloric acid.

6. The nanofilled reinforced high efficiency flame retardant polypropylene material according to claim 1, wherein, The concentration of the boric acid is 5-15g / L.

7. The nanofilled reinforced high efficiency flame retardant polypropylene material according to claim 1, wherein, The concentration of the phytic acid is 5-15g / L.

8. The nanofilled reinforced high efficiency flame retardant polypropylene material according to claim 1, characterized in that, The concentration of the dispersion liquid is 1-10g / L.

9. The nanofilled reinforced high efficiency flame retardant polypropylene material according to claim 1, characterized in that, The preparation steps comprise the following steps: The polypropylene material comprises 100 parts of polypropylene, 20-30 parts of the flame-retardant silica sol, 0.5-1 part of dicumyl peroxide, 10-15 parts of modified zinc oxide whiskers, 50-60 parts of the masterbatch A, 10-20 parts of maleic anhydride grafted polypropylene, 10-15 parts of the nano filler, and 1-5 parts of vinyltrimethoxysilane.

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