CN113512231A - Rubber-plastic foaming auxiliary agent and preparation method thereof - Google Patents

Abstract

The invention discloses a rubber and plastic foaming auxiliary agent, which comprises the following raw materials: modified carbon nano tube, modified zinc oxide and expanded microsphere; the invention also discloses a preparation method of the rubber and plastic foaming auxiliary agent, which comprises the steps of firstly acidifying the carbon nano tube in concentrated sulfuric acid and concentrated nitric acid solution, then the acidified carbon nano tube and diethylenetriamine are subjected to an amide reaction under the action of a dicyclohexylcarbodiimide condensing agent to obtain an aminated carbon nano tube, finally, beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) acryloyl chloride and active hydrogen on amino of the aminated carbon nano tube are subjected to substitution to obtain a modified carbon nano tube, the expanded microsphere takes cyclopentane with a lower boiling point as a core material, taking a polymer as a shell, prolonging the heating path of cyclopentane, taking sodium thiocyanate and 3-chloropropyltriethoxysilane as raw materials, preparing a silane coupling agent containing thiocyano under the action of a catalyst, and modifying zinc oxide by using the coupling agent to obtain modified zinc oxide.

Description

Rubber-plastic foaming auxiliary agent and preparation method thereof

Technical Field

The invention belongs to the technical field of rubber plastic processing aids, and particularly relates to a rubber plastic foaming aid and a preparation method thereof.

Background

The rubber plastic product is produced by using rubber and high molecular polymer as base materials and adopting a physical foaming or chemical foaming method, so as to obtain a spongy rubber plastic porous structure product, and the technology is widely applied to various production industries at present, such as automobile door and window sealing strips, buffer pads, building construction gaskets, anti-seismic materials, sports protection facilities and the like.

The foaming agent is the most critical link in the whole rubber and plastic material preparation, and the selection is closely related to the working efficiency and the working quality. Generally speaking, a scientific and reasonable foaming agent is required to be selected for preparing a foaming product with good performance, the dosage and the using method of the foaming agent are required to meet the current social development requirements, at present, the foaming agent mainly contains an organic foaming agent and an inorganic foaming agent, wherein the inorganic foaming agent mainly refers to sodium bicarbonate, ammonium bicarbonate, urea and the like, the foaming agent has the advantages of high decomposition speed and low temperature in application, carbon dioxide and ammonia gas are decomposed, the rubber structure has large permeability coefficient when the gases exist, closed-cell foaming rubber is difficult to prepare, the prepared rubber and plastic product has low quality, low strength, large shrinkage rate and easy deformation, the commonly used organic foaming agent mainly contains N-dimethyl formamide, nitroso, diphenyl sulfonyl hydrazide ether and the like, the decomposition temperature of the materials in application is about more than 200 ℃, therefore, other foaming auxiliary agents are required to be added in the production process, such as urea, magnesium oxide and the like, but the existing foaming auxiliary agent has poor compatibility with a rubber and plastic base material, single function and high decomposition and deflation speed, and the instantly generated hot air can cause the collapse or combination of foam holes and reduce the quality of the rubber and plastic foaming material.

Disclosure of Invention

The invention aims to provide a rubber and plastic foaming auxiliary agent and a preparation method thereof.

The technical problems to be solved by the invention are as follows:

the existing foaming auxiliary agent has poor compatibility with a rubber and plastic base material, single function and high decomposition and deflation speed, and hot gas generated instantly can cause the collapse or combination of foam holes, thereby reducing the quality of the rubber and plastic foaming material.

The purpose of the invention can be realized by the following technical scheme:

the rubber and plastic foaming auxiliary agent comprises the following raw materials in parts by weight: 1-3 parts of modified carbon nano tube, 1-3 parts of modified zinc oxide and 1-3 parts of expanded microsphere;

the preparation method of the rubber and plastic foaming auxiliary agent comprises the following steps:

adding the modified carbon nano tube, the modified zinc oxide and the expanded microsphere into a stirring tank, and uniformly mixing to obtain the rubber and plastic foaming auxiliary agent.

Further, the modified carbon nanotube is prepared by the following steps:

step A1, adding a carbon nano tube, concentrated sulfuric acid and concentrated nitric acid into a conical flask, carrying out ultrasonic oscillation for 4 hours at the room temperature and the frequency of 25-35kHz, then adding deionized water for dilution, filtering by using a microporous membrane with the aperture of 450nm after dilution, washing a filter cake by using distilled water until a washing liquid is neutral, and then carrying out vacuum drying for 4 hours at the temperature of 80 ℃ to obtain an acidified carbon nano tube;

step A2, adding an acidified carbon nano tube, diethylenetriamine and dicyclohexylcarbodiimide into a single-neck flask, heating to 120 ℃, carrying out reflux reaction for 36-48h, then adding absolute ethyl alcohol, carrying out ultrasonic treatment for 20-40min at the frequency of 30-50kHz, filtering with a microporous membrane, washing a filter cake with deionized water for 3-5 times, and finally drying in an oven at the temperature of 80 ℃ for 4h to obtain an aminated carbon nano tube;

step A3, adding an aminated carbon nanotube, deionized water and absolute ethyl alcohol into a round-bottom flask, stirring for 5min at the rotating speed of 60-100min, controlling the reaction temperature to 0 ℃, simultaneously dropwise adding a benzene solution of beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) acryloyl chloride with the mass fraction of 13.66% and a potassium carbonate solution with the mass fraction of 20% into the round-bottom flask by using a constant-pressure dropping funnel under the protection of nitrogen, controlling the pH value to 9-10, after dropwise adding, heating to 25 ℃, reacting at the constant temperature of 200r/min at the rotating speed of 100r/min for 24h, performing suction filtration, respectively washing a filter cake for 2-3 times by using distilled water and benzene, and finally drying in a vacuum box at the temperature of 50 ℃ for 6-10h to obtain the modified carbon nanotube.

Further, in the step A1, the using amount ratio of the carbon nano-tubes to the concentrated sulfuric acid to the concentrated nitric acid is 1 g: 120mL of: 30mL, wherein the using amount of deionized water is 5-8 times of the volume of concentrated sulfuric acid, the mass fraction of the concentrated sulfuric acid is 95%, and the mass fraction of the concentrated nitric acid is 68%; in the step A2, the mass ratio of the acidified carbon nano tube to the diethylenetriamine to the dicyclohexylcarbodiimide is 0.6: 80-90: 12, the using amount of the absolute ethyl alcohol is 80-100% of the mass of the diethylenetriamine; in the step A3, the dosage ratio of the benzene solution of the aminated carbon nanotube, the deionized water, the absolute ethyl alcohol and the beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) acryloyl chloride is 1-3 g: 30-50 mL: 20mL of: 50 mL.

Further, the modified zinc oxide is prepared by the following steps:

step S11, adding sodium thiocyanate and cyclohexane into a three-neck flask, stirring for 5min at the rotating speed of 30-50r/min, heating until the cyclohexane refluxes, reacting for 1h, and then distilling, azeotropically dehydrating to obtain dry sodium thiocyanate;

step S12, adding dry sodium thiocyanate into a three-neck flask under the protection of nitrogen, then adding N, N-dimethylformamide, tetrabutylammonium bromide and 3-chloropropyltriethoxysilane into the three-neck flask, raising the temperature to 130 ℃, reacting for 3 hours at the rotation speed of 200 and 300r/min, naturally cooling to room temperature, filtering, washing a filter cake with absolute ethyl alcohol for 3-5 times, combining filtrates, distilling at normal pressure to remove ethyl alcohol, distilling at the pressure of 30mmHg to remove N, N-dimethylformamide, and then rectifying at the pressure of 1mmHg under reduced pressure to obtain a coupling agent;

and S13, adding deionized water, absolute ethyl alcohol and zinc oxide into a beaker, performing ultrasonic dispersion for 20min at the frequency of 20-40kHz, heating to 85 ℃, then dropwise adding the coupling agent obtained in the step S12 into the beaker, controlling the dropwise adding speed to be 1-3 drops/second, continuing performing ultrasonic treatment for 30min after the dropwise adding is finished and the frequency is not changed, then filtering, washing a filter cake with distilled water for 3-5 times, and drying in an oven at the temperature of 80-90 ℃ to constant weight to obtain the modified zinc oxide.

Further, in step S11, the ratio of the amounts of sodium thiocyanate and cyclohexane is 1 g: 5-8mL, wherein the dosage ratio of the dried sodium thiocyanate, the N, N-dimethylformamide, the tetrabutylammonium bromide and the 3-chloropropyltriethoxysilane in the step S12 is 1.05 mol: 30-50 mL: 0.05-0.1 g: 1 mol; in the step S13, the mass ratio of the deionized water to the absolute ethyl alcohol to the zinc oxide to the coupling agent is 240: 100: 60: 1-2.

Further, the expanded microspheres are made by the steps of:

step S21, adding acrylonitrile, methacrylonitrile, methacrylate, ethylene glycol dimethacrylate, lauroyl peroxide and cyclopentane into a reaction kettle, and uniformly stirring at the rotating speed of 60-80r/min to obtain an oil phase combination;

step S22, adding deionized water, sodium chloride, silica sol, polyvinylpyrrolidone solution and sodium nitrite into a beaker, uniformly stirring, adding into the reaction kettle in the step S21, mixing at a rotation speed of 100 + 200r/min for 30min, transferring into a homogenizer, stirring at a rotation speed of 7000r/min for 10min, transferring into a high-pressure reaction kettle, controlling the initial pressure to be 0.3MPa and the temperature to be 60 ℃ under the protection of nitrogen, reacting for 20h, cooling, decompressing, discharging, filtering, washing, and finally drying in a 50 ℃ oven to constant weight to obtain the expanded microspheres.

Further, in step S21, the mass ratio of acrylonitrile, methacrylonitrile, methacrylate, ethylene glycol dimethacrylate, lauroyl peroxide and cyclopentane is 28: 12: 10: 0.3: 1.0: 30, of a nitrogen-containing gas; in the step S22, the mass ratio of the deionized water to the sodium chloride to the silica sol to the polyvinylpyrrolidone solution to the sodium nitrite is 150: 25: 20: 0.3:0.001, the content of silicon dioxide in the silica sol is 20 percent, and the mass fraction of the polyvinylpyrrolidone solution is 3.6 percent.

Further, the preparation method of the rubber and plastic foaming auxiliary agent comprises the following steps:

adding the modified carbon nano tube, the modified zinc oxide and the expanded microsphere into a stirring tank, and uniformly mixing to obtain the rubber and plastic foaming auxiliary agent.

The invention has the beneficial effects that:

the invention takes modified carbon nano-tube, modified zinc oxide and expanded microsphere as raw materials, and the raw materials are uniformly mixed according to a specific proportion to obtain the rubber and plastic foaming auxiliary agent, firstly, the carbon nano-tube is acidified in concentrated sulfuric acid and concentrated nitric acid solution, so that the surface of the carbon nano-tube contains active functional groups-COOH, and then the acidified carbon nano-tube and diethylenetriamine generate amide reaction under the action of dicyclohexylcarbodiimide condensing agent to obtain an aminated carbon nano-tube, and finally, beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) acryloyl chloride and active hydrogen on amino of the aminated carbon nano-tube are replaced to generate the modified carbon nano-tube, wherein the carbon nano-tube has good mechanical property and heat conductivity, and can absorb and transfer heat generated by high-temperature decomposition of foaming agent in the foaming process of rubber and plastic products to prevent the rubber and plastic products from being damaged by incandescence, the carbon nano tube is used as an inorganic filler and can play a toughening and reinforcing effect, beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) acryloyl chloride is grafted on the carbon nano tube to endow the carbon nano tube with hindered phenol and hindered amine structures, so that the dispersibility of the carbon nano tube in a polymer matrix is improved on one hand, the aging resistance of a rubber plastic material is improved on the other hand, a silane coupling agent containing thiocyano is prepared by taking sodium thiocyanate and 3-chloropropyltriethoxysilane as raw materials under the action of a catalyst, zinc oxide is modified by using the coupling agent, the compatibility of the zinc oxide in the rubber plastic matrix is improved, the tear resistance, wear resistance and other properties of a rubber material are improved, the zinc oxide can accept lone pair electrons, the decomposition temperature of a foaming agent can be reduced, and the rubber plastic material is prevented from being damaged in a high-temperature environment, the expansion microsphere takes cyclopentane with a lower boiling point as a core material and a polymer as a shell, prolongs the heating path of the cyclopentane, improves the foaming temperature of the cyclopentane, and can adjust the use temperature range of the foaming agent by mixing the cyclopentane with a high-temperature foaming agent for use.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The rubber and plastic foaming auxiliary agent comprises the following raw materials in parts by weight: 1 part of modified carbon nano tube, 1 part of modified zinc oxide and 1 part of expanded microsphere;

the preparation method of the rubber and plastic foaming auxiliary agent comprises the following steps:

adding the modified carbon nano tube, the modified zinc oxide and the expanded microsphere into a stirring tank, and uniformly mixing to obtain the rubber and plastic foaming auxiliary agent.

Wherein the modified carbon nanotube is prepared by the following steps:

step A1, adding a carbon nano tube, concentrated sulfuric acid and concentrated nitric acid into a conical flask, carrying out ultrasonic oscillation at the frequency of 25kHz for 4 hours at room temperature, then adding deionized water for dilution, filtering with a microporous membrane with the aperture of 450nm after dilution, washing a filter cake with distilled water until a washing liquid is neutral, and carrying out vacuum drying at 80 ℃ for 4 hours to obtain an acidified carbon nano tube;

step A2, adding an acidified carbon nano tube, diethylenetriamine and dicyclohexylcarbodiimide into a single-mouth flask, heating to 120 ℃, carrying out reflux reaction for 36 hours, then adding absolute ethyl alcohol, carrying out ultrasonic treatment for 20 minutes at the frequency of 30kHz, filtering by using a microporous membrane, washing a filter cake for 3 times by using deionized water, and finally drying in an oven at the temperature of 80 ℃ for 4 hours to obtain an aminated carbon nano tube;

step A3, adding an aminated carbon nanotube, deionized water and absolute ethyl alcohol into a round-bottom flask, stirring for 5min at a rotation speed of 60min, controlling the reaction temperature to be 0 ℃, simultaneously dropwise adding a benzene solution of beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) acryloyl chloride with the mass fraction of 13.66% and a potassium carbonate solution with the mass fraction of 20% into the round-bottom flask by using a constant-pressure dropping funnel under the protection of nitrogen, controlling the pH value to be 9, after dropwise adding, heating to 25 ℃, reacting for 24h at a constant temperature at a rotation speed of 100r/min, carrying out suction filtration, washing a filter cake for 2 times by using distilled water and benzene respectively, and finally drying for 6h in a vacuum box at the temperature of 50 ℃ to obtain the modified carbon nanotube.

Wherein the dosage ratio of the carbon nano tube, the concentrated sulfuric acid and the concentrated nitric acid in the step A1 is 1 g: 120mL of: 30mL, wherein the using amount of deionized water is 5 times of the volume of concentrated sulfuric acid, the mass fraction of the concentrated sulfuric acid is 95%, and the mass fraction of the concentrated nitric acid is 68%; in the step A2, the mass ratio of the acidified carbon nano tube to the diethylenetriamine to the dicyclohexylcarbodiimide is 0.6: 80: 12, the using amount of the absolute ethyl alcohol is 80 percent of the mass of the diethylenetriamine; in the step A3, the dosage ratio of the benzene solution of the aminated carbon nanotube, the deionized water, the absolute ethyl alcohol and the beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) acryloyl chloride is 1 g: 30mL of: 20mL of: 50 mL.

Wherein the modified zinc oxide is prepared by the following steps:

step S11, adding sodium thiocyanate and cyclohexane into a three-neck flask, stirring for 5min at the rotation speed of 30r/min, heating until the cyclohexane refluxes, reacting for 1h, and then distilling, azeotropically dehydrating to obtain dry sodium thiocyanate;

step S12, adding dry sodium thiocyanate into a three-neck flask under the protection of nitrogen, then adding N, N-dimethylformamide, tetrabutylammonium bromide and 3-chloropropyltriethoxysilane into the three-neck flask, raising the temperature to 130 ℃, reacting for 3 hours at the rotating speed of 200r/min, naturally cooling to room temperature, filtering, washing a filter cake for 3 times by using absolute ethyl alcohol, combining filtrate, distilling at normal pressure to remove ethyl alcohol, distilling at reduced pressure of 30mmHg to remove N, N-dimethylformamide, and rectifying at reduced pressure of 1mmHg to obtain a coupling agent;

and S13, adding deionized water, absolute ethyl alcohol and zinc oxide into a beaker, performing ultrasonic dispersion for 20min at the frequency of 20kHz, heating to 85 ℃, then dropwise adding the coupling agent obtained in the step S12 into the beaker, controlling the dropwise adding speed to be 1 drop/second, keeping the frequency unchanged after the dropwise adding is finished, continuing performing ultrasonic treatment for 30min, filtering, washing a filter cake for 3 times by using distilled water, and drying in an oven at the temperature of 80 ℃ to constant weight to obtain the modified zinc oxide.

Wherein the dosage ratio of the sodium thiocyanate to the cyclohexane in the step S11 is 1 g: 5mL, wherein the usage ratio of the dried sodium thiocyanate, the N, N-dimethylformamide, the tetrabutylammonium bromide and the 3-chloropropyltriethoxysilane in the step S12 is 1.05 mol: 30mL of: 0.05 g: 1 mol; in the step S13, the mass ratio of the deionized water to the absolute ethyl alcohol to the zinc oxide to the coupling agent is 240: 100: 60: 1.

wherein the expanded microspheres are prepared by the following steps:

step S21, adding acrylonitrile, methacrylonitrile, methacrylate, ethylene glycol dimethacrylate, lauroyl peroxide and cyclopentane into a reaction kettle, and uniformly stirring at the rotation speed of 60r/min to obtain an oil phase combination;

step S22, adding deionized water, sodium chloride, silica sol, polyvinylpyrrolidone solution and sodium nitrite into a beaker, uniformly stirring, adding into the reaction kettle in the step S21, mixing for 30min at a rotation speed of 100r/min, transferring into a homogenizer, stirring for 10min at a rotation speed of 7000r/min, transferring into a high-pressure reaction kettle, controlling the initial pressure to be 0.3MPa and the temperature to be 60 ℃ under the protection of nitrogen, reacting for 20h, cooling, decompressing, discharging, filtering, washing, and finally drying in a 50 ℃ oven to constant weight to obtain the expanded microspheres.

Wherein in the step S21, the mass ratio of acrylonitrile, methacrylonitrile, methacrylate, ethylene glycol dimethacrylate, lauroyl peroxide and cyclopentane is 28: 12: 10: 0.3: 1.0: 30, of a nitrogen-containing gas; in the step S22, the mass ratio of the deionized water to the sodium chloride to the silica sol to the polyvinylpyrrolidone solution to the sodium nitrite is 150: 25: 20: 0.3:0.001, the content of silicon dioxide in the silica sol is 20 percent, and the mass fraction of the polyvinylpyrrolidone solution is 3.6 percent.

Example 2

The rubber and plastic foaming auxiliary agent comprises the following raw materials in parts by weight: 2 parts of modified carbon nano tube, 2 parts of modified zinc oxide and 2 parts of expanded microsphere;

the preparation method of the rubber and plastic foaming auxiliary agent comprises the following steps:

adding the modified carbon nano tube, the modified zinc oxide and the expanded microsphere into a stirring tank, and uniformly mixing to obtain the rubber and plastic foaming auxiliary agent.

Wherein the modified carbon nanotube is prepared by the following steps:

step A1, adding a carbon nano tube, concentrated sulfuric acid and concentrated nitric acid into a conical flask, carrying out ultrasonic oscillation at the frequency of 30kHz for 4 hours at room temperature, then adding deionized water for dilution, filtering with a microporous membrane with the aperture of 450nm after dilution, washing a filter cake with distilled water until a washing liquid is neutral, and carrying out vacuum drying for 4 hours at the temperature of 80 ℃ to obtain an acidified carbon nano tube;

step A2, adding an acidified carbon nano tube, diethylenetriamine and dicyclohexylcarbodiimide into a single-mouth flask, heating to 120 ℃, carrying out reflux reaction for 40h, then adding absolute ethyl alcohol, carrying out ultrasonic treatment for 30min at the frequency of 40kHz, filtering by using a microporous membrane, washing a filter cake for 4 times by using deionized water, and finally drying in an oven at the temperature of 80 ℃ for 4h to obtain an aminated carbon nano tube;

step A3, adding an aminated carbon nanotube, deionized water and absolute ethyl alcohol into a round-bottom flask, stirring for 5min at a rotating speed of 80min, controlling the reaction temperature to be 0 ℃, simultaneously dropwise adding a benzene solution of beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) acryloyl chloride with the mass fraction of 13.66% and a potassium carbonate solution with the mass fraction of 20% into the round-bottom flask by using a constant-pressure dropping funnel under the protection of nitrogen, controlling the pH value to be 9, after dropwise adding, heating to 25 ℃, reacting for 24h at a constant temperature at a rotating speed of 150r/min, carrying out suction filtration, washing a filter cake for 2 times by using distilled water and benzene respectively, and finally drying for 8h in a vacuum box at a temperature of 50 ℃ to obtain the modified carbon nanotube.

Wherein the dosage ratio of the carbon nano tube, the concentrated sulfuric acid and the concentrated nitric acid in the step A1 is 1 g: 120mL of: 30mL, wherein the using amount of deionized water is 7 times of the volume of concentrated sulfuric acid, the mass fraction of the concentrated sulfuric acid is 95%, and the mass fraction of the concentrated nitric acid is 68%; in the step A2, the mass ratio of the acidified carbon nano tube to the diethylenetriamine to the dicyclohexylcarbodiimide is 0.6: 85: 12, the using amount of the absolute ethyl alcohol is 90 percent of the mass of the diethylenetriamine; in the step A3, the dosage ratio of the benzene solution of the aminated carbon nanotube, the deionized water, the absolute ethyl alcohol and the beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) acryloyl chloride is 2 g: 40mL of: 20mL of: 50 mL.

Wherein the modified zinc oxide is prepared by the following steps:

step S11, adding sodium thiocyanate and cyclohexane into a three-neck flask, stirring for 5min at the rotating speed of 40r/min, heating until the cyclohexane refluxes, reacting for 1h, and then distilling, azeotropically dehydrating to obtain dry sodium thiocyanate;

step S12, adding dry sodium thiocyanate into a three-neck flask under the protection of nitrogen, then adding N, N-dimethylformamide, tetrabutylammonium bromide and 3-chloropropyltriethoxysilane into the three-neck flask, raising the temperature to 130 ℃, reacting for 3 hours at the rotation speed of 250r/min, naturally cooling to room temperature, filtering, washing a filter cake with absolute ethyl alcohol for 4 times, combining filtrates, distilling at normal pressure to remove ethyl alcohol, distilling under reduced pressure of 30mmHg to remove N, N-dimethylformamide, and rectifying under reduced pressure of 1mmHg to obtain a coupling agent;

and S13, adding deionized water, absolute ethyl alcohol and zinc oxide into a beaker, performing ultrasonic dispersion for 20min at the frequency of 30kHz, heating to 85 ℃, then dropwise adding the coupling agent obtained in the step S12 into the beaker, controlling the dropwise adding speed to be 2 drops/second, keeping the frequency unchanged after the dropwise adding is finished, continuing performing ultrasonic treatment for 30min, filtering, washing a filter cake for 4 times by using distilled water, and drying in an oven at the temperature of 85 ℃ to constant weight to obtain the modified zinc oxide.

Wherein the dosage ratio of the sodium thiocyanate to the cyclohexane in the step S11 is 1 g: 7mL, wherein the using amount ratio of the dried sodium thiocyanate, the N, N-dimethylformamide, the tetrabutylammonium bromide and the 3-chloropropyltriethoxysilane in the step S12 is 1.05 mol: 40mL of: 0.08 g: 1 mol; in the step S13, the mass ratio of the deionized water to the absolute ethyl alcohol to the zinc oxide to the coupling agent is 240: 100: 60: 1.

wherein the expanded microspheres are prepared by the following steps:

step S21, adding acrylonitrile, methacrylonitrile, methacrylate, ethylene glycol dimethacrylate, lauroyl peroxide and cyclopentane into a reaction kettle, and uniformly stirring at the rotation speed of 70r/min to obtain an oil phase combination;

step S22, adding deionized water, sodium chloride, silica sol, polyvinylpyrrolidone solution and sodium nitrite into a beaker, uniformly stirring, adding into the reaction kettle in the step S21, mixing for 30min at a rotation speed of 150r/min, transferring into a homogenizer, stirring for 10min at a rotation speed of 7000r/min, transferring into a high-pressure reaction kettle, controlling the initial pressure to be 0.3MPa and the temperature to be 60 ℃ under the protection of nitrogen, reacting for 20h, cooling, decompressing, discharging, filtering, washing, and finally drying in a 50 ℃ oven to constant weight to obtain the expanded microspheres.

Wherein in the step S21, the mass ratio of acrylonitrile, methacrylonitrile, methacrylate, ethylene glycol dimethacrylate, lauroyl peroxide and cyclopentane is 28: 12: 10: 0.3: 1.0: 30, of a nitrogen-containing gas; in the step S22, the mass ratio of the deionized water to the sodium chloride to the silica sol to the polyvinylpyrrolidone solution to the sodium nitrite is 150: 25: 20: 0.3:0.001, the content of silicon dioxide in the silica sol is 20 percent, and the mass fraction of the polyvinylpyrrolidone solution is 3.6 percent.

Example 3

The rubber and plastic foaming auxiliary agent comprises the following raw materials in parts by weight: 3 parts of modified carbon nano tube, 3 parts of modified zinc oxide and 3 parts of expanded microsphere;

the preparation method of the rubber and plastic foaming auxiliary agent comprises the following steps:

adding the modified carbon nano tube, the modified zinc oxide and the expanded microsphere into a stirring tank, and uniformly mixing to obtain the rubber and plastic foaming auxiliary agent.

Wherein the modified carbon nanotube is prepared by the following steps:

step A1, adding a carbon nano tube, concentrated sulfuric acid and concentrated nitric acid into a conical flask, carrying out ultrasonic oscillation at the frequency of 35kHz for 4 hours at room temperature, then adding deionized water for dilution, filtering with a microporous membrane with the aperture of 450nm after dilution, washing a filter cake with distilled water until a washing liquid is neutral, and carrying out vacuum drying for 4 hours at the temperature of 80 ℃ to obtain an acidified carbon nano tube;

step A2, adding an acidified carbon nano tube, diethylenetriamine and dicyclohexylcarbodiimide into a single-mouth flask, heating to 120 ℃, carrying out reflux reaction for 48 hours, then adding absolute ethyl alcohol, carrying out ultrasonic treatment for 40 minutes at the frequency of 50kHz, filtering by using a microporous membrane, washing a filter cake for 5 times by using deionized water, and finally drying in an oven at the temperature of 80 ℃ for 4 hours to obtain an aminated carbon nano tube;

step A3, adding an aminated carbon nanotube, deionized water and absolute ethyl alcohol into a round-bottom flask, stirring for 5min at the rotation speed of 100min, controlling the reaction temperature to be 0 ℃, simultaneously dropwise adding a benzene solution of beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) acryloyl chloride with the mass fraction of 13.66% and a potassium carbonate solution with the mass fraction of 20% into the round-bottom flask by using a constant-pressure dropping funnel under the protection of nitrogen, controlling the pH value to be 10, after dropwise adding, heating to 25 ℃, reacting at the constant temperature of 200r/min for 24h, carrying out suction filtration, washing a filter cake for 3 times by using distilled water and benzene respectively, and finally drying for 10h in a vacuum box at the temperature of 50 ℃ to obtain the modified carbon nanotube.

Wherein the dosage ratio of the carbon nano tube, the concentrated sulfuric acid and the concentrated nitric acid in the step A1 is 1 g: 120mL of: 30mL, wherein the using amount of deionized water is 8 times of the volume of concentrated sulfuric acid, the mass fraction of the concentrated sulfuric acid is 95%, and the mass fraction of the concentrated nitric acid is 68%; in the step A2, the mass ratio of the acidified carbon nano tube to the diethylenetriamine to the dicyclohexylcarbodiimide is 0.6: 90: 12, the using amount of the absolute ethyl alcohol is 100 percent of the mass of the diethylenetriamine; in the step A3, the dosage ratio of the benzene solution of the aminated carbon nanotube, the deionized water, the absolute ethyl alcohol and the beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) acryloyl chloride is 3 g: 50mL of: 20mL of: 50 mL.

Wherein the modified zinc oxide is prepared by the following steps:

step S11, adding sodium thiocyanate and cyclohexane into a three-neck flask, stirring for 5min at a rotation speed of 50r/min, heating until the cyclohexane refluxes, reacting for 1h, and then distilling, azeotropically dehydrating to obtain dry sodium thiocyanate;

step S12, adding dry sodium thiocyanate into a three-neck flask under the protection of nitrogen, then adding N, N-dimethylformamide, tetrabutylammonium bromide and 3-chloropropyltriethoxysilane into the three-neck flask, raising the temperature to 130 ℃, reacting for 3 hours at the rotating speed of 300r/min, naturally cooling to room temperature, filtering, washing a filter cake for 5 times with absolute ethyl alcohol, combining filtrates, distilling at normal pressure to remove ethyl alcohol, distilling at reduced pressure of 30mmHg to remove N, N-dimethylformamide, and rectifying at reduced pressure of 1mmHg to obtain a coupling agent;

and S13, adding deionized water, absolute ethyl alcohol and zinc oxide into a beaker, performing ultrasonic dispersion for 20min at the frequency of 40kHz, heating to 85 ℃, then dropwise adding the coupling agent obtained in the step S12 into the beaker, controlling the dropwise adding speed to be 3 drops/second, keeping the frequency unchanged after the dropwise adding is finished, continuing performing ultrasonic treatment for 30min, filtering, washing a filter cake for 5 times by using distilled water, and drying in an oven at the temperature of 90 ℃ to constant weight to obtain the modified zinc oxide.

Wherein the dosage ratio of the sodium thiocyanate to the cyclohexane in the step S11 is 1 g: 8mL, wherein the using amount ratio of the dried sodium thiocyanate, the N, N-dimethylformamide, the tetrabutylammonium bromide and the 3-chloropropyltriethoxysilane in the step S12 is 1.05 mol: 50mL of: 0.1 g: 1 mol; in the step S13, the mass ratio of the deionized water to the absolute ethyl alcohol to the zinc oxide to the coupling agent is 240: 100: 60: 2.

wherein the expanded microspheres are prepared by the following steps:

step S21, adding acrylonitrile, methacrylonitrile, methacrylate, ethylene glycol dimethacrylate, lauroyl peroxide and cyclopentane into a reaction kettle, and uniformly stirring at a rotating speed of 80r/min to obtain an oil phase combination;

step S22, adding deionized water, sodium chloride, silica sol, polyvinylpyrrolidone solution and sodium nitrite into a beaker, uniformly stirring, adding into the reaction kettle in the step S21, mixing for 30min at a rotation speed of 200r/min, transferring into a homogenizer, stirring for 10min at a rotation speed of 7000r/min, transferring into a high-pressure reaction kettle, controlling the initial pressure to be 0.3MPa and the temperature to be 60 ℃ under the protection of nitrogen, reacting for 20h, cooling, decompressing, discharging, filtering, washing, and finally drying in a 50 ℃ oven to constant weight to obtain the expanded microspheres.

Wherein in the step S21, the mass ratio of acrylonitrile, methacrylonitrile, methacrylate, ethylene glycol dimethacrylate, lauroyl peroxide and cyclopentane is 28: 12: 10: 0.3: 1.0: 30, of a nitrogen-containing gas; in the step S22, the mass ratio of the deionized water to the sodium chloride to the silica sol to the polyvinylpyrrolidone solution to the sodium nitrite is 150: 25: 20: 0.3:0.001, the content of silicon dioxide in the silica sol is 20 percent, and the mass fraction of the polyvinylpyrrolidone solution is 3.6 percent.

Comparative example 1

The comparative example is zinc stearate.

Comparative example 2

The comparative example was urea.

Carrying out performance test on the foaming agent auxiliaries of the examples 1-3 and the comparative examples 1-3, wherein the test process comprises the steps of putting 100 parts by weight of silicone rubber into a roll of an open mill, then sequentially adding 100 parts by weight of white carbon black and 25 parts by weight of 3A molecular sieve, mixing for 30min, transferring into a 175 ℃ electric heating constant temperature drying box for heat treatment for 70min, sequentially adding 3 parts by weight of foaming agent H, 0.4 part by weight of foaming auxiliary and 1 part by weight of vulcanizing agent DCBP, continuously mixing for 2H to obtain a film, fixing the film by using a glass flat plate, then placing into a 150 ℃ electric heating blast box, treating for 30min, transferring into a 175 ℃ electric heating constant temperature drying box for treatment for 60min to obtain rubber foaming materials, carrying out five groups of tests, respectively adopting the examples 1-3 and the comparative examples 1-2 as the foaming auxiliary, and observing and recording the performance of each group of rubber foaming materials;

1. tensile strength: measured according to GB/T10654-2001;

2. hardness: measured according to GB/T531-1992;

3. apparent density: also called apparent density, is an important index for measuring sponge porogenic material, and the density (rho) is calculated by the following formula

ρ = W/V, wherein: w represents the mass g of the sample in the air; v-volume cm of the sample³；

4. Microstructure: cutting the obtained foaming material by a blade, and observing the uniformity degree of gaps;

5. aging resistance: aging in hot air at 150 ℃ for 166h, and observing the hardness change, wherein the change is qualified when the change is 0-5%; the test results are shown in the following table:

item	Tensile strength/MPa	hardness/A	Surface density	Microstructure	Rate of change of hardness
						Example 1	1.25	35	0.9	Uniform voids	1.0
Example 2	1.28	33	0.85	Uniform voids	0.9
						Example 3	1.30	37	0.88	Uniform voids	1.2
Comparative example 1	0.8	42	1.0	Uneven gap	4.1
						Comparative example 2	1.0	45	1.05	Uneven gap	4.8

As can be seen from the above table, the rubber foaming products of examples 1-3 are superior to comparative examples 1-2 in tensile property, hardness, surface density, microstructure and aging resistance test processes, which shows that the foaming aid prepared by the invention has higher practical value.

The foregoing is merely exemplary and illustrative of the principles of the present invention and various modifications, additions and substitutions of the specific embodiments described herein may be made by those skilled in the art without departing from the principles of the present invention or exceeding the scope of the claims set forth herein.

Claims (8)

1. The rubber and plastic foaming auxiliary agent is characterized by comprising the following raw materials in parts by weight: 1-3 parts of modified carbon nano tube, 1-3 parts of modified zinc oxide and 1-3 parts of expanded microsphere;

the preparation method of the rubber and plastic foaming auxiliary agent comprises the following steps:

adding the modified carbon nano tube, the modified zinc oxide and the expanded microsphere into a stirring tank, and uniformly mixing to obtain the rubber and plastic foaming auxiliary agent.

2. The rubber-plastic foaming aid according to claim 1, wherein the modified carbon nanotubes are prepared by the following steps:

step A1, adding a carbon nano tube, concentrated sulfuric acid and concentrated nitric acid into a conical flask, carrying out ultrasonic oscillation for 4 hours at the room temperature and the frequency of 25-35kHz, then adding deionized water for dilution, filtering by using a microporous membrane with the aperture of 450nm after dilution, washing a filter cake by using distilled water until a washing liquid is neutral, and then carrying out vacuum drying for 4 hours at the temperature of 80 ℃ to obtain an acidified carbon nano tube;

step A2, adding an acidified carbon nano tube, diethylenetriamine and dicyclohexylcarbodiimide into a single-neck flask, heating to 120 ℃, carrying out reflux reaction for 36-48h, then adding absolute ethyl alcohol, carrying out ultrasonic treatment for 20-40min at the frequency of 30-50kHz, filtering with a microporous membrane, washing a filter cake with deionized water for 3-5 times, and finally drying in an oven at the temperature of 80 ℃ for 4h to obtain an aminated carbon nano tube;

step A3, adding an aminated carbon nanotube, deionized water and absolute ethyl alcohol into a round-bottom flask, stirring for 5min at the rotating speed of 60-100min, controlling the reaction temperature to 0 ℃, simultaneously dropwise adding a benzene solution of beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) acryloyl chloride with the mass fraction of 13.66% and a potassium carbonate solution with the mass fraction of 20% into the round-bottom flask by using a constant-pressure dropping funnel under the protection of nitrogen, controlling the pH value to 9-10, after dropwise adding, heating to 25 ℃, reacting at the constant temperature of 200r/min at the rotating speed of 100r/min for 24h, performing suction filtration, respectively washing a filter cake for 2-3 times by using distilled water and benzene, and finally drying in a vacuum box at the temperature of 50 ℃ for 6-10h to obtain the modified carbon nanotube.

3. The rubber-plastic foaming aid according to claim 2, wherein the amount ratio of the carbon nanotubes, the concentrated sulfuric acid and the concentrated nitric acid in step A1 is 1 g: 120mL of: 30mL, wherein the using amount of deionized water is 5-8 times of the volume of concentrated sulfuric acid, the mass fraction of the concentrated sulfuric acid is 95%, and the mass fraction of the concentrated nitric acid is 68%; in the step A2, the mass ratio of the acidified carbon nano tube to the diethylenetriamine to the dicyclohexylcarbodiimide is 0.6: 80-90: 12, the using amount of the absolute ethyl alcohol is 80-100% of the mass of the diethylenetriamine; in the step A3, the dosage ratio of the benzene solution of the aminated carbon nanotube, the deionized water, the absolute ethyl alcohol and the beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) acryloyl chloride is 1-3 g: 30-50 mL: 20mL of: 50 mL.

4. The rubber-plastic foaming aid according to claim 1, wherein the modified zinc oxide is prepared by the following steps:

step S11, adding sodium thiocyanate and cyclohexane into a three-neck flask, stirring for 5min at the rotating speed of 30-50r/min, heating until the cyclohexane refluxes, reacting for 1h, and then distilling, azeotropically dehydrating to obtain dry sodium thiocyanate;

step S12, adding dry sodium thiocyanate into a three-neck flask under the protection of nitrogen, then adding N, N-dimethylformamide, tetrabutylammonium bromide and 3-chloropropyltriethoxysilane into the three-neck flask, raising the temperature to 130 ℃, reacting for 3 hours at the rotation speed of 200 and 300r/min, naturally cooling to room temperature, filtering, washing a filter cake with absolute ethyl alcohol for 3-5 times, combining filtrates, distilling at normal pressure to remove ethyl alcohol, distilling at the pressure of 30mmHg to remove N, N-dimethylformamide, and then rectifying at the pressure of 1mmHg under reduced pressure to obtain a coupling agent;

and S13, adding deionized water, absolute ethyl alcohol and zinc oxide into a beaker, performing ultrasonic dispersion for 20min at the frequency of 20-40kHz, heating to 85 ℃, then dropwise adding the coupling agent obtained in the step S12 into the beaker, controlling the dropwise adding speed to be 1-3 drops/second, continuing performing ultrasonic treatment for 30min after the dropwise adding is finished and the frequency is not changed, then filtering, washing a filter cake with distilled water for 3-5 times, and drying in an oven at the temperature of 80-90 ℃ to constant weight to obtain the modified zinc oxide.

5. The rubber-plastic foaming aid according to claim 4, wherein the ratio of the sodium thiocyanate to the cyclohexane in step S11 is 1 g: 5-8mL, wherein the dosage ratio of the dried sodium thiocyanate, the N, N-dimethylformamide, the tetrabutylammonium bromide and the 3-chloropropyltriethoxysilane in the step S12 is 1.05 mol: 30-50 mL: 0.05-0.1 g: 1 mol; in the step S13, the mass ratio of the deionized water to the absolute ethyl alcohol to the zinc oxide to the coupling agent is 240: 100: 60: 1-2.

6. The rubber-plastic foaming aid according to claim 1, wherein the expanded microspheres are prepared by the following steps:

step S21, adding acrylonitrile, methacrylonitrile, methacrylate, ethylene glycol dimethacrylate, lauroyl peroxide and cyclopentane into a reaction kettle, and uniformly stirring at the rotating speed of 60-80r/min to obtain an oil phase combination;

step S22, adding deionized water, sodium chloride, silica sol, polyvinylpyrrolidone solution and sodium nitrite into a beaker, uniformly stirring, adding into the reaction kettle in the step S21, mixing at a rotation speed of 100 + 200r/min for 30min, transferring into a homogenizer, stirring at a rotation speed of 7000r/min for 10min, transferring into a high-pressure reaction kettle, controlling the initial pressure to be 0.3MPa and the temperature to be 60 ℃ under the protection of nitrogen, reacting for 20h, cooling, decompressing, discharging, filtering, washing, and finally drying in a 50 ℃ oven to constant weight to obtain the expanded microspheres.

7. The rubber-plastic foaming aid according to claim 6, wherein in step S21, the mass ratio of acrylonitrile, methacrylonitrile, methacrylate, ethylene glycol dimethacrylate, lauroyl peroxide and cyclopentane is 28: 12: 10: 0.3: 1.0: 30, of a nitrogen-containing gas; in the step S22, the mass ratio of the deionized water to the sodium chloride to the silica sol to the polyvinylpyrrolidone solution to the sodium nitrite is 150: 25: 20: 0.3:0.001, the content of silicon dioxide in the silica sol is 20 percent, and the mass fraction of the polyvinylpyrrolidone solution is 3.6 percent.

8. The preparation method of the rubber-plastic foaming aid according to claim 1, characterized by comprising the following steps:

adding the modified carbon nano tube, the modified zinc oxide and the expanded microsphere into a stirring tank, and uniformly mixing to obtain the rubber and plastic foaming auxiliary agent.