Organic-inorganic composite flame retardant and application thereof in waterproof material

Abstract

The invention belongs to the technical field of flame-retardant materials, and particularly relates to an organic-inorganic composite flame retardant and application thereof in waterproof materials. The organic-inorganic composite flame retardant provided by the invention is relatively high in content of flame-retardant elements such as N, P and the like and does not contain halogen, and through the synergistic effect of the silicoaluminophosphate molecular sieve and organic components, the compatibility of the flame retardant and a matrix is improved, and the flame-retardant property and mechanical strength of the material are effectively improved; meanwhile, toxic and corrosive gas generated when the flame-retardant polymer is heated or burnt can be effectively avoided, and the environmental protection property of the flame retardant is improved. Tests prove that when the flame retardant is used for preparing the polyolefin waterproof material, the flame retardant grade of the waterproof material can be remarkably improved, the heat release rate and the smoke generation amount are effectively reduced, and meanwhile the mechanical strength of the material is effectively improved. Therefore, the invention can provide a technical basis for the development of polyolefin flame retardants, and has wide application prospects in polyolefin waterproof materials.

Description

Technical Field

[0001] The present invention belongs to the technical field of flame retardant materials, and particularly relates to an organic-inorganic composite flame retardant and its application in waterproof materials. Background Art

[0002] Polyolefin waterproof materials have advantages such as low price, easy molding, chemical corrosion resistance, and good insulation, and have been widely used in fields such as automobiles, electronic information, household appliances, pipes, packaging, construction, transportation, and chemical engineering. However, like many polymer materials, polyolefin waterproof materials have disadvantages such as poor thermal stability and high flammability. Moreover, during the combustion process of polyolefin waterproof materials, molten droplets are easily generated, which can easily cause the spread of fire and lead to serious fires. In addition, a large amount of heat is released during the combustion process of polyolefin waterproof materials, which will cause direct harm to people's lives and property. At the same time, a large amount of toxic smoke will also be released, causing secondary personal harm and environmental damage. Therefore, it is of great significance to improve the flame retardant performance of polyolefin waterproof materials through flame retardants.

[0003] In the prior art, a patent for invention with the application number 202111452235.0 discloses a flame retardant for PP and its preparation method. Using 2,2,6,6-tetramethylpiperidinol, 1-(2-bromoethenyl)-4-trifluoromethylbenzene, DOPO, and ethyl undecanoate as raw materials, a flame retardant for polypropylene (PP) is obtained through substitution, addition, and transesterification reactions. Although this flame retardant has good flame retardant effects, it contains halogens in its components and belongs to organic halogen flame retardants. A large amount of smoke and toxic and corrosive gases such as hydrogen halide will be released during the combustion process, which is extremely likely to cause secondary harm to the human body and limit the scope of product use.

[0004] Halogen-free intumescent flame retardants (IFR) are currently a research hotspot in the field of flame retardants. A patent for invention with the application number 202111239160.8 discloses an intumescent flame retardant based on piperazine pyrophosphate / melamine cyanurate / ammonium polyphosphate. However, pure intumescent flame retardants have problems such as a relatively high addition amount, slow charring rate, and poor quality of the char layer that is prone to fragmentation. In the patent for invention with the application number 201810082502.1, CeMnO3 perovskite-type composite oxides are combined with a nitrogen and phosphorus-containing flame retardant, and the flame retardant effect of the nitrogen and phosphorus-containing flame retardant is synergistically enhanced through the CeMnO3 perovskite-type composite oxides. Although synergistically enhancing organic nitrogen and phosphorus flame retardants through inorganic synergists is an effective method to improve the flame retardant effect of organic nitrogen and phosphorus flame retardants, the compatibility between inorganic synergists and PP is poor, which easily leads to uneven distribution of inorganic synergists in the polymer, thereby affecting the flame retardant and mechanical properties of PP.

[0005] Therefore, the development of a flame retardant for polyolefin waterproof materials with high flame retardancy efficiency and good compatibility with the matrix is of great significance for expanding the application scope and use safety of polyolefin waterproof materials. Summary of the Invention

[0006] In order to overcome the deficiencies of the prior art, the purpose of the present invention is to provide an organic-inorganic composite flame retardant and its application in waterproof materials. The organic-inorganic composite flame retardant provided by the present invention does not contain halogens, has good compatibility with the polyolefin matrix, and has excellent flame retardancy performance, and can solve the problems that the existing flame retardants have poor compatibility with the polyolefin waterproof material matrix, uneven distribution of the flame retardant in the matrix, resulting in poor flame retardancy performance and decreased mechanical properties of the modified polyolefin waterproof materials.

[0007] To achieve the above purpose, in the first aspect of the present invention, an organic-inorganic composite flame retardant is provided, and the organic-inorganic composite flame retardant is mainly obtained by reacting a flame retardant precursor, an intermediate and an organic amine;

[0008] Among them, the flame retardant precursor is mainly obtained by reacting a phosphosilicoaluminate molecular sieve, cyanuric chloride and an alkali source; the phosphosilicoaluminate molecular sieve is mainly obtained by hydrothermal reaction of an aluminum source, a silicon source, a phosphorus source, a template agent and an alkali source; the intermediate is mainly obtained by reacting 4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxide and phosphoric acid under the action of a catalyst.

[0009] As a preferred embodiment of the present invention, the organic amine is selected from one or two of ethylenediamine and triethylamine; the aluminum source is sodium aluminate or aluminum isopropoxide; the silicon source is silica sol or tetraethyl orthosilicate; the phosphorus source is phosphoric acid or phosphorus pentoxide; the template agent is 4-amino-3,5-dimethyl-N,N-dimethylhydroxypiperidine or 4-amino-2,6-dimethyl-N,N-dimethylhydroxypiperidine; the alkali source is ammonia water or sodium hydroxide; the catalyst is selected from one or two of concentrated sulfuric acid and p-toluenesulfonic acid.

[0010] In the second aspect of the present invention, a preparation method of the above organic-inorganic composite flame retardant is provided, including the following steps:

[0011] (1) Hydrothermally react the aluminum source, silicon source, phosphorus source, template agent and alkali source in water, then filter, wash and dry the obtained product to obtain a phosphosilicoaluminate molecular sieve; react the phosphosilicoaluminate molecular sieve with cyanuric chloride and an alkali source to obtain a flame retardant precursor;

[0012] Separately react 4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxide, phosphoric acid and a catalyst, then wash and dry to obtain an intermediate;

[0013] (2) React the flame retardant precursor and intermediate obtained in step (1) with an organic amine, and then wash and dry to obtain the organic-inorganic composite flame retardant.

[0014] Based on the consideration of improving the reaction efficiency and product yield, as a preferred embodiment of the present invention, in step (1), the reaction mass ratio of the aluminum source, silicon source, phosphorus source, template agent, and base source is 1∶(1 - 60)∶(2 - 30)∶(0.5 - 15)∶(0.2 - 20); the reaction mass ratio of the aluminophosphate molecular sieve, cyanuric chloride, and base source is 1∶(0.2 - 0.5)∶(0.4 - 1.5); the reaction mass ratio of 4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxide, phosphoric acid, and catalyst is 1∶(0.1 - 0.2)∶(0.1 - 0.2).

[0015] As a preferred embodiment of the present invention, in step (1), the hydrothermal reaction temperature is 130 - 200 °C, and the time is 48 - 120 h; the reaction temperature of the aluminophosphate molecular sieve with cyanuric chloride and base source is 0 - 10 °C, the pH is 5 - 6, and the reaction time is 6 - 8 h; the reaction temperature of 4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxide, phosphoric acid, and catalyst is 40 - 50 °C, and the time is 24 - 36 h.

[0016] As a preferred embodiment of the present invention, in step (1), the specific process of the reaction of the aluminophosphate molecular sieve with cyanuric chloride and base source is as follows: First, disperse the aluminophosphate molecular sieve in a first solvent to obtain a mixed solution A, and disperse cyanuric chloride in a second solvent to obtain a mixed solution B. Further, simultaneously add the mixed solution B and the base source dropwise to the mixed solution A for reaction; the first solvent is selected from one or two of water and ethanol; the second solvent is one or two of ethanol and 1,4-dioxane.

[0017] As a preferred embodiment of the present invention, in step (2), the specific process of the reaction of the flame retardant precursor, intermediate, and organic amine is as follows: Mix the flame retardant precursor and a third solvent, then add the intermediate and a part of the organic amine, stir at room temperature for 4 - 6 h, then raise the temperature to 50 - 60 °C and react for 4 - 6 h, then raise the temperature to 90 - 100 °C, add the remaining organic amine, and continue to react for 6 - 8 h; the third solvent is selected from one or two of water and ethanol; the mass ratio of the flame retardant precursor, intermediate, part of the organic amine, and remaining organic amine is 1∶(0.1 - 0.3)∶(0.02 - 0.05)∶(0.15 - 0.20).

[0018] The third aspect of the present invention provides the application of the above-mentioned organic-inorganic composite flame retardant as a flame retardant additive in polyolefin waterproof materials; the polyolefin waterproof material is one of P-type TPO waterproof materials, L-type TPO waterproof materials, and H-type TPO waterproof materials.

[0019] The fourth aspect of the present invention provides a polyolefin waterproof material. The preparation method of the polyolefin waterproof material includes the following steps: adding the organic-inorganic composite flame retardant to the pellets of the polyolefin waterproof material, then melt-blending, cooling and pelletizing, and calendering with a three-roll mill to obtain the polyolefin waterproof material; wherein, the organic-inorganic composite flame retardant is the organic-inorganic composite flame retardant as described above.

[0020] As a preferred embodiment of the present invention, the polyolefin waterproof material is one of P-type TPO waterproof materials, L-type TPO waterproof materials, and H-type TPO waterproof materials; the addition amount of the organic-inorganic composite flame retardant in the polyolefin waterproof material is 5-20 wt%.

[0021] The technical solution of the present invention has the following advantages and beneficial effects:

[0022] First, in the preparation process of the organic-inorganic composite flame retardant of the present invention, aluminum source, silicon source, phosphorus source, template agent, and alkali source are first used to prepare aluminosilicate phosphate molecular sieve. Further, the amino group on the template agent in the cage of the aluminosilicate phosphate molecular sieve reacts with cyanuric chloride, and the aluminosilicate phosphate molecular sieve is grafted onto the molecular structure of the organic flame retardant. This not only increases the addition amount of the inorganic component in the flame retardant, but also maximally improves the dispersion of the inorganic aluminosilicate phosphate molecular sieve in the organic flame retardant, effectively improving the compatibility of the inorganic molecular sieve component in the flame retardant resin and avoiding the migration and precipitation of the inorganic molecular sieve component from the flame retardant resin. At the same time, the abundant hydroxyl groups on the surface of the aluminosilicate phosphate molecular sieve are easy to form hydrogen bonds with the oxygen-containing, nitrogen-containing, and hydroxyl groups in the organic flame retardant component, which can further improve the interaction between the organic and inorganic flame retardant components and improve the structural stability of the organic-inorganic composite flame retardant, effectively avoiding the separation of the organic and inorganic flame retardant components during the preparation of the flame retardant polymer.

[0023] Second, for the polyolefin waterproof material prepared by modification with the organic-inorganic composite flame retardant of the present invention, during the combustion process, the hindered amine free radicals generated by the decomposition of cyanuric chloride and organic amine can capture the combustible free radicals generated by the degradation of the polymer in the air, generating stable alcohols and ketones, reducing the degree of combustion; the triazine organic free radicals decomposed by cyanuric chloride react chemically with the phosphorus-containing organic substances generated by the decomposition of 4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxide, and a carbon-containing high polymer with a cross-linked structure is generated. When the high polymer changes from the molten state to the semi-solid state, the viscosity increases sharply; at the same time, gases such as NH3, H2O, and CO2 generated by combustion enter the carbon layer, generating an expanded, dense and continuous barrier carbon layer, which can effectively prevent the transfer of heat and combustible gases between the polymer matrix, further improving the flame retardancy efficiency of the material.

[0024] Third, for the polyolefin waterproof material prepared by modification with the organic-inorganic composite flame retardant of the present invention, during the combustion process, the aluminosilicate phosphate molecular sieve has high thermal stability and can play a role in physical flame retardancy during the combustion of the modified flame retardant resin; the acid (H + ) on the surface of the aluminosilicate phosphate molecular sieve has a synergistic effect with the organic flame retardant component, catalyzing the cross-linking and carbonization reaction of the organic flame retardant, further promoting the formation of the expanded carbon layer. The template agent in the pores of the aluminosilicate phosphate molecular sieve decomposes to generate non-combustible gases such as CO2 and water vapor to reduce the concentration of combustible gases and reduce the degree of combustion; the Lewis acid (Al 4+ ) and the template agent on the surface of the aluminosilicate phosphate molecular sieve decompose to generate nitroxyl radicals that can capture the alkyl radicals and peroxy radicals generated by the thermal decomposition of the resin matrix, inhibiting the degradation and combustion of the resin matrix, effectively reducing the degree of combustion, even extinguishing the flame, and undergoing a cross-linking and carbonization reaction under the catalytic action of acid (H + ), further strengthening the expanded carbon layer; the aluminosilicate phosphate molecular sieve is embedded in the expanded carbon layer, acting as a supporting framework to further increase the strength and density of the carbon layer, playing a role in heat insulation and oxygen isolation and high-efficiency flame retardancy. At the same time, the relatively large pore volume of the aluminosilicate phosphate molecular sieve can absorb the flue gas generated during the combustion of the flame retardant resin matrix, achieving a good smoke suppression effect.

[0025] Fourth, experiments have confirmed that for the organic-inorganic composite flame retardant of the present invention, the limiting oxygen index (LOI) of the prepared polyolefin waterproof material is 30.5% - 32.2%, the flame retardant grade is UL 94V-0, the heat release rate is 125.2 - 138.5 kW / m 2 , and the smoke generation amount is 0.025 - 0.033 m 2, the tensile strength is 17.5 - 31.7 MPa, and the flame retardant migration rate is 1.3% - 1.6%. It shows that the organic-inorganic composite flame retardant of the present invention, after being applied to polyolefin resin materials, not only has good compatibility with the matrix and is not easy to migrate, but also can significantly improve the flame retardant grade and mechanical strength of the materials, and effectively reduce the heat release rate and the amount of smoke generated.

[0026] Generally speaking, the organic-inorganic composite flame retardant provided by the present invention has a relatively high content of flame retardant elements such as N and P, and does not contain halogens. At the same time, it combines the two mechanisms of solid-phase flame retardancy and gas-phase flame retardancy. Through the synergy of aluminosilicate phosphate molecular sieve and organic components, the flame retardant efficiency and mechanical strength of the organic-inorganic composite flame retardant are improved, and it can also effectively avoid the generation of toxic and corrosive gases when the flame-retarded polymer is heated or burned, improve the environmental protection of the flame retardant, and broaden the application range of the flame retardant. Therefore, the present invention can provide a novel and efficient solution for the flame retardant application of polyolefin materials, and also provide a technical basis for the development of new flame retardants. Detailed implementation mode

[0027] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention will be further described in detail below in conjunction with specific implementation modes. It should be noted that, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0028] Among them, the ammonia water involved in the following implementation modes is a commercially available product with a concentration of 25% - 28%.

[0029] The pellets of P-type TPO waterproof material, the pellets of L-type TPO waterproof material, and the pellets of H-type TPO waterproof material used in the following examples and comparative examples all come from Jiangsu Karen Building Materials Co., Ltd. Other raw materials and preparation methods involved in the following implementation modes are all conventional materials and technologies in the art unless otherwise specified. In addition, in the following implementation modes, "room temperature" generally refers to 20 - 30 °C understood in the art.

[0030] Example 1

[0031] This example provides an organic-inorganic composite flame retardant, and its preparation method includes the following steps:

[0032] (1) At room temperature, 10 g of sodium aluminate, 10 g of silica sol, 20 g of phosphorus pentoxide, 5 g of 4-amino-3,5-dimethyl-N,N-dimethylhydroxypiperidine, 200 g of ammonia water, and 1000 g of deionized water are added to a reaction kettle. After stirring at 25 °C for 5 h, the reaction is carried out at 130 °C for 120 h, then filtered and washed, and dried at 120 °C for 24 h, and then cooled to room temperature to obtain aluminosilicate phosphate molecular sieve;

[0033] At room temperature, 10 g of the as-prepared aluminophosphate molecular sieve and 500 g of deionized water were added to a reaction kettle, and ultrasonic stirring was carried out to fully disperse the aluminophosphate molecular sieve in water, obtaining a mixed solution 1; additionally, 2 g of cyanuric chloride and 20 g of ethanol were added to the reaction kettle, and ultrasonic stirring was carried out under the condition of 0 °C, obtaining a stably dispersed mixed solution 2; the mixed solution 2 and 15 g of ammonia water were simultaneously and slowly added dropwise to the mixed solution 1, and the temperature inside the reaction kettle was maintained not to exceed 10 °C during the dropping process, and then the reaction was carried out at 0 °C and a pH of 5 for 8 h to obtain a flame retardant precursor.

[0034] (2) At room temperature, 10 g of 4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxide, 1 g of phosphoric acid, 1 g of concentrated sulfuric acid, and 500 g of ethyl acetate were added to a reaction kettle, and after reacting at 40 °C for 36 h, the solvent was removed by rotary evaporation, washed with deionized water until the washing liquid was neutral, and dried at 100 °C for 24 h to obtain an intermediate.

[0035] (3) At room temperature, 10 g of the flame retardant precursor obtained in step (1) and 500 g of deionized water were added to a reaction kettle, 1 g of the intermediate obtained in step (2) and 0.2 g of ethylenediamine were slowly added to the reaction kettle under stirring, stirred for 4 h, heated to 50 °C and then continued to react for 6 h, subsequently heated to 90 °C, and 1.5 g of ethylenediamine was continuously added dropwise and continued to react for 8 h. After the reaction was completed, the solvent was removed by rotary evaporation, washed with deionized water until the washing liquid was neutral, and dried at 100 °C for 24 h to obtain an organic-inorganic composite flame retardant.

[0036] This example also provides a flame retardant polyolefin waterproof material, and its preparation method includes the following steps:

[0037] 20 g of the organic-inorganic composite flame retardant prepared in this example was added to 80 g of the pellet of P-type TPO waterproof material, after mixing evenly, melt-blended at 200 °C, cooled and pelletized, and calendared at 60 °C to obtain a flame retardant polyolefin waterproof material.

[0038] Example 2

[0039] This example provides an organic-inorganic composite flame retardant, and its preparation method includes the following steps:

[0040] (1) At room temperature, 10 g of aluminum isopropoxide, 600 g of tetraethyl orthosilicate, 300 g of phosphoric acid, 150 g of 4-amino-2,6-dimethyl-N,N-dimethylhydroxypiperidine, 2 g of sodium hydroxide, and 2000 g of deionized water were added to a reaction kettle, stirred at 80 °C for 1 h, reacted at 200 °C for 48 h, then filtered and washed, dried at 180 °C for 12 h, and cooled to room temperature to obtain an aluminophosphate molecular sieve;

[0041] At room temperature, 10 g of the aluminophosphate molecular sieve prepared above and 1000 g of ethanol were added to a reaction kettle, and ultrasonic stirring was carried out to fully disperse the aluminophosphate molecular sieve in the solvent, obtaining a mixed solution 1; separately, 5 g of cyanuric chloride and 100 g of 1,4-dioxane were added to a reaction kettle, and ultrasonic stirring was carried out at 10 °C to obtain a stably dispersed mixed solution 2; the mixed solution 2 and 4 g of sodium hydroxide were simultaneously and slowly added dropwise to the mixed solution 1, and the temperature in the reaction kettle was maintained not to exceed 10 °C during the dropping process, and the reaction was carried out at 10 °C and pH 6 for 6 h to obtain a flame retardant precursor.

[0042] (2) At room temperature, 10 g of 4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxide, 2 g of phosphoric acid, 2 g of p-toluenesulfonic acid, and 1000 g of acetone were added to a reaction kettle, and the reaction was carried out at 50 °C for 24 h. After the solvent was removed by rotary evaporation, it was washed with deionized water until the washing liquid was neutral, and dried at 120 °C for 12 h to obtain an intermediate.

[0043] (3) At room temperature, 10 g of the flame retardant precursor obtained in step (1) and 1000 g of ethanol were added to a reaction kettle. Under stirring, 3 g of the intermediate obtained in step (2) and 0.5 g of triethylamine were slowly added to the reaction kettle, and stirred for 6 h. After heating to 60 °C, the reaction was continued for 4 h, and then heated to 100 °C, and 2 g of triethylamine was continuously added dropwise and the reaction was continued for 6 h. After the reaction was completed, the solvent was removed by rotary evaporation, washed with deionized water until the washing liquid was neutral, and dried at 120 °C for 12 h to obtain an organic-inorganic composite flame retardant.

[0044] This example also provides a flame retardant polyolefin waterproof material, and its preparation method includes the following steps:

[0045] 5 g of the organic-inorganic composite flame retardant prepared in this example was added to 95 g of the pellets of L-type TPO waterproof material. After mixing evenly, melt blending was carried out at 160 °C, followed by cooling and pelletizing, and three-roll calendering molding at 60 °C to obtain a flame retardant polyolefin waterproof material.

[0046] Example 3

[0047] This example provides an organic-inorganic composite flame retardant, and its preparation method includes the following steps:

[0048] (1) At room temperature, 10 g of sodium aluminate, 300 g of tetraethyl orthosilicate, 100 g of phosphorus pentoxide, 100 g of 4-amino-3,5-dimethyl-N,N-dimethylhydroxypiperidine, 100 g of sodium hydroxide, and 1500 g of deionized water were added to a reaction kettle. After stirring at 60 °C for 3 h, the reaction was carried out at 160 °C for 72 h, then filtered and washed, and dried at 160 °C for 18 h, and then cooled to room temperature to obtain an aluminophosphate molecular sieve;

[0049] At room temperature, 10 g of the aluminophosphate-silicate molecular sieve prepared above and 800 g of a mixed solvent of deionized water and ethanol with a volume ratio of 1:1 were added to a reaction kettle, and ultrasonic stirring was carried out to make the aluminophosphate-silicate molecular sieve fully dispersed in the solvent, obtaining mixed solution 1; additionally, 3 g of cyanuric chloride and 50 g of a mixed solvent of ethanol and 1,4-dioxane were added to the reaction kettle, and ultrasonic stirring was carried out at 5 °C to obtain a stably dispersed mixed solution 2; mixed solution 2 and 10 g of sodium hydroxide were simultaneously and slowly added dropwise to mixed solution 1, and the temperature inside the reaction kettle was maintained not to exceed 10 °C during the dropping process, and the reaction was carried out at 5 °C and a pH of 6 for 7 h to obtain a flame retardant precursor.

[0050] (2) At room temperature, 10 g of 4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxide, 1.5 g of phosphoric acid, 1.5 g of concentrated sulfuric acid, and 800 g of a mixed solvent of ethyl acetate and acetone were added to a reaction kettle, and after reacting at 45 °C for 30 h, the solvent was removed by rotary evaporation, washed with deionized water until the washing liquid was neutral, and dried at 110 °C for 18 h to obtain an intermediate.

[0051] (3) At room temperature, 10 g of the flame retardant precursor obtained in step (1) and 800 g of a mixed solvent of deionized water and ethanol were added to a reaction kettle, 2 g of the intermediate obtained in step (2) and 0.3 g of a mixture of ethylenediamine and triethylamine with a mass ratio of 1:1 were slowly added to the reaction kettle under stirring, stirred for 5 h, heated to 60 °C and continued to react for 5 h, then heated to 95 °C, and 1.8 g of a mixture of ethylenediamine and triethylamine was continuously added dropwise and reacted for 7 h. After the reaction was completed, the solvent was removed by rotary evaporation, washed with deionized water until the washing liquid was neutral, and dried at 110 °C for 20 h to obtain an organic-inorganic composite flame retardant.

[0052] This example also provides a flame retardant polyolefin waterproof material, and its preparation method includes the following steps:

[0053] 10 g of the organic-inorganic composite flame retardant prepared in this example was added to 90 g of pellets of H-type TPO waterproof material, and after mixing evenly, melt blending was carried out at 180 °C, followed by cooling and pelletizing, and calendering molding was carried out at 60 °C with a three-roll mill to obtain a flame retardant polyolefin waterproof material.

[0054] Comparative Example 1

[0055] This comparative example provides an organic flame retardant. Compared with Example 1, no aluminophosphate-silicate molecular sieve inorganic component was added in its preparation method, and an organic flame retardant was prepared. The specific preparation method includes the following steps:

[0056] (1) At room temperature, 5 g of 4-amino-3,5-dimethyl-N,N-dimethylhydroxypiperidine and 1000 g of deionized water were added to a reaction kettle, and ultrasonic stirring was carried out to obtain a mixed solution 1; another 2 g of cyanuric chloride and 20 g of ethanol were added to the reaction kettle, and ultrasonic stirring was carried out at 0 °C to obtain a stably dispersed mixed solution 2; the mixed solution 2 and 15 g of ammonia water were simultaneously and slowly added dropwise to the mixed solution 1, and the temperature in the reaction kettle was kept not exceeding 10 °C during the dropping process, and the reaction was carried out at 0 °C and pH 5 for 8 h to obtain a flame retardant precursor.

[0057] (2) At room temperature, 10 g of 4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxide, 1 g of phosphoric acid, 1 g of concentrated sulfuric acid, and 500 g of ethyl acetate were added to a reaction kettle, and the reaction was carried out at 40 °C for 36 h. After rotary evaporation to remove the solvent, it was washed with deionized water until the washing liquid was neutral, and dried at 100 °C for 24 h to obtain an intermediate.

[0058] (3) At room temperature, 10 g of the flame retardant precursor obtained in step (1) and 500 g of deionized water were added to a reaction kettle. Under stirring, 1 g of the intermediate obtained in step (2) and 0.2 g of ethylenediamine were slowly added to the reaction kettle, and stirring was carried out for 4 h. After heating to 50 °C, the reaction was continued for 6 h. Subsequently, the temperature was raised to 90 °C, and 1.5 g of ethylenediamine was continuously added dropwise and the reaction was continued for 8 h. After the reaction was completed, the solvent was removed by rotary evaporation, and it was washed with deionized water until the washing liquid was neutral, and dried at 100 °C for 24 h to obtain an organic flame retardant.

[0059] This comparative example also provides a flame retardant polyolefin waterproof material, and its preparation method includes the following steps:

[0060] 20 g of the organic flame retardant prepared in this comparative example was added to 80 g of the pellet of P-type TPO waterproof material. After mixing evenly, melt blending was carried out at 200 °C, followed by cooling and pelletizing, and calendering at 60 °C to obtain a flame retardant polyolefin waterproof material.

[0061] Comparative Example 2

[0062] This comparative example provides a flame retardant. Compared with Example 1, its preparation method only has a phosphosilicoaluminate molecular sieve inorganic component, and the specific preparation method includes the following steps:

[0063] At room temperature, 10 g of sodium aluminate, 10 g of silica sol, 20 g of phosphorus pentoxide, 5 g of 4-amino-3,5-dimethyl-N,N-dimethylhydroxypiperidine, 200 g of ammonia water, and 1000 g of deionized water were added to a reaction kettle. After stirring at 25 °C for 5 h, the reaction was carried out at 130 °C for 120 h, then filtered and washed, and after drying at 120 °C for 24 h, it was cooled to room temperature to obtain phosphosilicoaluminate molecular sieve, which was directly used as a flame retardant.

[0064] This comparative example also provides a flame-retardant polyolefin waterproof material, and its preparation method includes the following steps:

[0065] Add 20 g of the aluminosilicate phosphate molecular sieve prepared in this comparative example to 80 g of the pellet of P-type TPO waterproof material. After mixing evenly, melt-blend at 200 °C, cool and pelletize, and roll and form at 60 °C to obtain the flame-retardant polyolefin waterproof material.

[0066] Comparative Example 3

[0067] This comparative example provides a flame retardant. Compared with Example 1, the inorganic component and the organic component of the aluminosilicate phosphate molecular sieve only undergo simple physical mixing. The specific preparation method includes the following steps:

[0068] (1) At room temperature, add 5 g of 4-amino-3,5-dimethyl-N,N-dimethylhydroxypiperidine and 1000 g of deionized water to the reaction kettle, and stir ultrasonically to obtain a mixed solution 1; add 2 g of cyanuric chloride and 20 g of ethanol to the reaction kettle, and stir ultrasonically at 0 °C to obtain a uniformly dispersed mixed solution 2; slowly drip the mixed solution 2 and 15 g of ammonia water into the mixed solution 1 at the same time, and keep the temperature in the reaction kettle not exceeding 10 °C during the dripping process. React at 0 °C and pH 5 for 8 h to obtain a flame retardant precursor.

[0069] (2) At room temperature, add 10 g of 4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxide, 1 g of phosphoric acid, 1 g of concentrated sulfuric acid, and 500 g of ethyl acetate to the reaction kettle, react at 40 °C for 36 h, then remove the solvent by rotary evaporation, wash with deionized water until the washing liquid is neutral, and dry at 100 °C for 24 h to obtain an intermediate.

[0070] (3) At room temperature, add 10 g of the flame retardant precursor obtained in step (1) and 500 g of deionized water to the reaction kettle. Slowly add 1 g of the intermediate obtained in step (2) and 0.2 g of ethylenediamine to the reaction kettle under stirring, stir for 4 h, raise the temperature to 50 °C and continue to react for 6 h, then raise the temperature to 90 °C, continue to add 1.5 g of ethylenediamine and continue to react for 8 h. After the reaction is completed, remove the solvent by rotary evaporation, wash with deionized water until the washing liquid is neutral, and dry at 100 °C for 24 h to obtain an organic flame retardant.

[0071] (4) At room temperature, add 10 g of sodium aluminate, 10 g of silica sol, 20 g of phosphorus pentoxide, 5 g of 4-amino-3,5-dimethyl-N,N-dimethylhydroxypiperidine, 200 g of ammonia water, and 1000 g of deionized water to the reaction kettle. Stir at 25 °C for 5 h, then react at 130 °C for 120 h, then filter and wash, dry at 120 °C for 24 h, and then cool to room temperature to obtain aluminosilicate phosphate molecular sieve.

[0072] This comparative example also provides a flame-retardant polyolefin waterproof material, and its preparation method includes the following steps:

[0073] Add 10 g of the silicon aluminum phosphate molecular sieve prepared in this comparative example and 10 g of the organic flame retardant prepared in this comparative example to 80 g of P-type TPO waterproof material pellets. After mixing evenly, melt-blend at 200 °C, cool and pelletize, and roll and form at 60 °C to obtain the flame-retardant polyolefin waterproof material.

[0074] Test Example

[0075] Perform performance tests on the flame-retardant polyolefin waterproof materials prepared with the flame retardants of Examples 1-3 and Comparative Examples 1-3 of the present invention.

[0076] Among them, the limiting oxygen index (LOI) is tested on an oxygen index instrument 1600 according to GB / T2406-2009; the combustibility experiment test is carried out on the sample strip on a horizontal and vertical burning tester CZF-5A according to the UL94 standard, and the combustible grade is recorded; the heat release rate and smoke generation amount of the sample are tested on a cone calorimeter FTT--iCone2+ according to the ISO5660 standard; the tensile strength of the sample is measured on a universal testing machine WDW-100E according to the GB / T1040.1-2006 standard; the flame retardant migration rate of the sample is tested according to the ISO 6427:2024 standard.

[0077] The specific test results are shown in Table 1 below.

[0078] Table 1: Performance test results of the flame-retardant polyolefin waterproof materials prepared in Examples 1-3 and Comparative Examples 1-3

[0079]

[0080] From the comparison between Example 1 and Comparative Example 1, it can be seen that after the inorganic component of silicon aluminum phosphate molecular sieve is not added, the flame retardant performance of the polyolefin waterproof material becomes worse, the LOI value drops from 32.2% to 28.4%, the flame retardant grade drops from UL 94V-0 to UL94V-1, and the heat release rate increases from 125.2 kW / m 2 to 237.2 kW / m 2 , and the smoke generation amount increases from 0.025 m 2 to 0.050 m 2This indicates that the aluminophosphate molecular sieve has a significant effect on improving the flame retardancy of polyolefin waterproof materials. In particular, after adding the aluminophosphate molecular sieve, the amount of smoke released is significantly reduced, indicating that the aluminophosphate molecular sieve can play a good smoke suppression effect. At the same time, through the comparison of the tensile strength and migration rate, it can be seen that after adding the inorganic component of the aluminophosphate molecular sieve in the present invention, compared with Comparative Example 1, the mechanical strength of the polyolefin waterproof material can be further improved, and the migration of the flame retardant can be reduced, indicating that the addition of the inorganic component of the aluminophosphate molecular sieve improves the compatibility between the flame retardant and the polyolefin matrix.

[0081] From the comparison between Example 1 and Comparative Example 2, it can be seen that after only adding the inorganic component of the aluminophosphate molecular sieve, the flame retardancy of the polyolefin waterproof material becomes worse. The LOI value drops from 32.2% to 24.2%, the flame retardancy rating drops from UL 94V-0 to UL 94V-2, and the heat release rate increases from 125.2 kW / m 2 to 240.0 kW / m 2 , and the amount of smoke generated increases from 0.025 m 2 to 0.045 m 2 . This shows that the simple aluminophosphate molecular sieve has an insignificant effect on improving the flame retardancy of polyolefin waterproof materials. In particular, after not adding the organic component, the LOI value of the polyolefin waterproof material drops significantly, indicating that the organic component plays an important role in improving the flame retardancy of the polyolefin waterproof material. Further, after only adding the inorganic component of the aluminophosphate molecular sieve, the migration rate of the flame retardant in the material rises to 6.1%, indicating that the compatibility between the flame retardant and the polyolefin matrix is poor and is not conducive to the stable performance of the material.

[0082] From the comparison between Example 1 and Comparative Example 3, it can be seen that after the inorganic component and the organic component of the aluminophosphate molecular sieve are physically mixed, the flame retardancy and mechanical properties of the polyolefin waterproof material become worse, and the migration rate increases. The LOI value drops from 32.2% to 29.1%, the flame retardancy rating drops from UL 94V-0 to UL 94V-2, and the heat release rate increases from 125.2 kW / m 2 to 219.6 kW / m 2 , and the amount of smoke generated increases from 0.025 m 2 to 0.046 m 2 , the tensile strength drops from 17.5 MPa to 14.8 MPa, and the migration rate increases from 1.5% to 3.5%. This shows that only when a composite flame retardant with a stable structure is formed between the inorganic and organic flame retardant components can the synergistic effect between the aluminophosphate molecular sieve and the organic component be maximally exerted, significantly improving the flame retardancy and mechanical strength of the polyolefin waterproof material, and improving the compatibility between the flame retardant and the matrix, and reducing the migration of the flame retardant.

[0083] From the performance test results of Examples 1 to 3, it can be seen that for the organic-inorganic composite flame retardant of the present invention, the LOI value of the prepared polyolefin waterproof material is 30.5% - 32.2%, the flame retardant grade is UL 94V-0, and the heat release rate is 125.2 - 138.5 kW / m 2 , and the smoke generation amount is 0.025 - 0.033 m 2 . The tensile strength is 17.5 - 31.7 MPa, and the migration rate is 1.3% - 1.6%. It shows that after the organic-inorganic composite flame retardant of the present invention is applied to the polyolefin waterproof material, it can significantly improve the flame retardant performance and mechanical strength of the material, and at the same time can effectively improve the compatibility between the flame retardant and the matrix.

[0084] In summary, the organic-inorganic composite flame retardant provided by the present invention has a relatively high content of flame retardant elements such as N and P, does not contain halogens, and combines both the solid-phase flame retardant and gas-phase flame retardant mechanisms. Through the synergistic effect of aluminosilicate phosphate molecular sieve and organic components, it effectively improves the compatibility between the flame retardant and the matrix, increases the flame retardant efficiency and mechanical strength of the polyolefin waterproof material, can also effectively avoid the generation of toxic and corrosive gases when the flame retardant polymer is heated or burned, improves the environmental protection of the flame retardant, and broadens the application range of the flame retardant. Therefore, the present invention can provide a novel and efficient solution for the flame retardant application of polyolefin waterproof materials, and can also provide a technical basis for the development of new flame retardants.

[0085] The above embodiments are only the preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantive changes and substitutions made by those skilled in the art based on the present invention belong to the scope of protection required by the present invention.

Claims

1. An organic-inorganic composite flame retardant, characterized in that, The organic-inorganic composite flame retardant is mainly obtained by reacting a flame retardant precursor, an intermediate and an organic amine; Among them, the flame retardant precursor is mainly obtained by reacting aluminosilicate phosphate molecular sieve, cyanuric chloride and an alkali source; the aluminosilicate phosphate molecular sieve is mainly obtained by hydrothermal reaction of an aluminum source, a silicon source, a phosphorus source, a template agent and an alkali source; the intermediate is mainly obtained by reacting 4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxide and phosphoric acid under the action of a catalyst.

2. The organic-inorganic composite flame retardant according to claim 1, characterized in that, The organic amine is selected from one or two of ethylenediamine and triethylamine; the aluminum source is sodium aluminate or aluminum isopropoxide; the silicon source is silica sol or tetraethyl orthosilicate; the phosphorus source is phosphoric acid or phosphorus pentoxide; the template agent is 4-amino-3,5-dimethyl-N,N-dimethylhydroxypiperidine or 4-amino-2,6-dimethyl-N,N-dimethylhydroxypiperidine; the alkali source is ammonia water or sodium hydroxide; the catalyst is selected from one or two of concentrated sulfuric acid and p-toluenesulfonic acid.

3. A method for preparing an organic-inorganic composite flame retardant as described in claim 1 or 2, characterized in that, It includes the following steps: (1) Hydrothermally react the aluminum source, silicon source, phosphorus source, template agent and alkali source in water, then filter, wash and dry the obtained product to obtain aluminosilicate phosphate molecular sieve; react the aluminosilicate phosphate molecular sieve with cyanuric chloride and an alkali source to obtain a flame retardant precursor; Separately react 4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxide, phosphoric acid and a catalyst, then wash and dry to obtain an intermediate; (2) React the flame retardant precursor and intermediate obtained in step (1) with an organic amine, then wash and dry to obtain the organic-inorganic composite flame retardant.

4. The preparation method of the organic-inorganic composite flame retardant according to claim 3, wherein, In step (1), the reaction mass ratio of the aluminum source, silicon source, phosphorus source, template agent and alkali source is 1∶(1~60)∶(2~30)∶(0.5~15)∶(0.2~20); the reaction mass ratio of the aluminosilicate phosphate molecular sieve, cyanuric chloride and an alkali source is 1∶(0.2~0.5)∶(0.4~1.5); the reaction mass ratio of 4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxide, phosphoric acid and a catalyst is 1∶(0.1~0.2)∶(0.1~0.2).

5. The preparation method of the organic-inorganic composite flame retardant according to claim 3, characterized in that, In step (1), the temperature of the hydrothermal reaction is 130~200 °C, and the time is 48~120 h; the reaction temperature of the aluminosilicate phosphate molecular sieve with cyanuric chloride and an alkali source is 0~10 °C, the pH is 5~6, and the reaction time is 6~8 h; the reaction temperature of 4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-oxide, phosphoric acid and a catalyst is 40~50 °C, and the time is 24~36 h.

6. The preparation method of the organic-inorganic composite flame retardant according to claim 3, characterized in that In step (1), the specific process of the reaction of the aluminophosphate molecular sieve with cyanuric chloride and the base source is as follows: First, the aluminophosphate molecular sieve is dispersed in the first solvent to obtain a mixed solution A, and cyanuric chloride is dispersed in the second solvent to obtain a mixed solution B. Further, the mixed solution B and the base source are simultaneously dropped into the mixed solution A for reaction; the first solvent is selected from one or two of water and ethanol; the second solvent is one or two of ethanol and 1,4-dioxane.

7. The preparation method of the organic-inorganic composite flame retardant according to claim 3, characterized in that, In step (2), the specific process of the reaction of the flame retardant precursor, the intermediate and the organic amine is as follows: The flame retardant precursor and the third solvent are mixed, then the intermediate and a part of the organic amine are added, and the mixture is stirred at room temperature for 4 to 6 h, then heated to 50 to 60 °C for reaction for 4 to 6 h, and then heated to 90 to 100 °C, and the remaining organic amine is added and the reaction is continued for 6 to 8 h; the third solvent is selected from one or two of water and ethanol; the mass ratio of the flame retardant precursor, the intermediate, the part of the organic amine and the remaining organic amine is 1∶(0.1~0.3)∶(0.02~0.05)∶(0.15~0.20).

8. Use of the organic-inorganic composite flame retardant according to claim 1 or 2, or the organic-inorganic composite flame retardant prepared by the preparation method according to any one of claims 3 to 7, characterized in that, Use as a flame retardant additive in polyolefin waterproof materials; the polyolefin waterproof material is one of P-type TPO waterproof materials, L-type TPO waterproof materials, and H-type TPO waterproof materials.

9. A polyolefin waterproof material, characterized in that, The preparation method of the polyolefin waterproof material includes the following steps: adding an organic-inorganic composite flame retardant to the pellets of the polyolefin waterproof material, then melt-blending, cooling and pelletizing, and calendering with a three-roll mill to obtain the polyolefin waterproof material; wherein, the organic-inorganic composite flame retardant is the organic-inorganic composite flame retardant as described in claim 1 or 2 or the organic-inorganic composite flame retardant prepared by using the preparation method described in any one of claims 3 to 7.

10. The polyolefin waterproof material according to claim 9, characterized in that, The polyolefin waterproof material is one of P-type TPO waterproof materials, L-type TPO waterproof materials, and H-type TPO waterproof materials; the addition amount of the organic-inorganic composite flame retardant in the polyolefin waterproof material is 5 to 20 wt%.

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