A modified carboxylated styrene-butadiene latex, its preparation process and application

Abstract

The invention relates to a modified carboxylated styrene butadiene latex, a preparation process and an application thereof, and belongs to the technical field of carboxylated styrene butadiene latex materials. A modified carboxylated styrene butadiene latex comprises components: carboxylated styrene butadiene composite latex, composite modified hollow glass microspheres, modified filler, zinc oxide, an antioxidant, a crosslinking agent and an accelerator; the modified filler is a mixture of montmorillonite and calcium carbonate modified by a silane coupling agent; the carboxylated styrene butadiene composite latex is composited by sorbic acid, carboxymethyl chitosan and carboxylated styrene butadiene latex; the invention introduces a variety of active groups, such as amino, carboxyl and hydroxyl groups, into the carboxylated styrene butadiene composite latex and the composite modified hollow glass microspheres to enhance the dispersibility and interface bonding ability of the hollow glass microspheres in the system. At the same time, these groups participate in the free radical reaction of the system and promote bonding with the matrix. The introduced benzene ring structure, hollow glass microspheres, zinc oxide and modified filler also significantly improve the mechanical properties and thermal stability of the material.

Description

Technical Field

[0001] The invention belongs to the technical field of carboxylated styrene butadiene latex materials and relates to a modified carboxylated styrene butadiene latex, a preparation process and an application thereof. Background Art

[0002] Carboxylated styrene butadiene latex is a copolymer produced by emulsion polymerization of butadiene, styrene, a small amount of carboxylic acid and other additives. It is a milky white aqueous dispersion with a bluish purple luster. It has a high proportion of styrene, high adhesion and film strength, good mechanical and chemical stability, excellent fluidity and storage stability, and a large filling volume.

[0003] Hollow glass microspheres, whose core component is borosilicate, exhibit a unique hollow thin-walled spherical structure, and their particle size range is usually between 10-250 microns. Due to its low density, high strength, excellent thermal insulation performance, and excellent fluidity and stability, this material is widely used as a filler in many fields. Its application history can be traced back to cutting-edge technology fields such as aerospace, oil and gas development, and buoyancy materials. With the continuous advancement of science and technology and the improvement of industrial production capacity, hollow glass microspheres have begun to enter the civilian fields such as coatings and adhesives.

[0004] However, when hollow glass microspheres are used as inorganic powder materials in organic resins, their dispersibility and compatibility are not ideal, which may have an adverse effect on the mechanical properties of the composite material. To solve this problem, the microspheres need to be modified before use to improve their dispersibility in the organic matrix and enhance their interfacial bonding strength.

[0005] In current research, silane coupling agents are often used as modifiers to improve the compatibility of hollow glass microspheres with polymer matrices. Its molecular structure contains carbon and silicon functional groups, which can react with the surface of inorganic powders and organic polymers at the same time, playing the role of a "bridge" connection. However, simply relying on silane coupling agents to modify the surface of hollow glass microspheres has a limited scope of application due to the limitations of its grafted structure, and its effect on improving the performance of composite materials is not significant. Summary of the invention

[0006] The object of the present invention is to provide a modified carboxylated styrene butadiene latex, a preparation process and an application thereof. The present invention introduces a variety of active groups, such as amino, carboxyl and hydroxyl, into carboxylated styrene butadiene composite latex and composite modified hollow glass microspheres, and utilizes hydrogen bond interaction to enhance the dispersibility and interface binding ability of the hollow glass microspheres in the system. At the same time, these groups participate in the free radical reaction of the carboxylated styrene butadiene latex system, promoting the binding with the matrix. In addition, the introduced benzene ring structure, hollow glass microspheres, zinc oxide and modified fillers also significantly improve the mechanical properties and thermal stability of the material.

[0007] The purpose of the present invention can be achieved through the following technical solutions:

[0008] A modified carboxyl styrene-butadiene latex comprises the following components in parts by weight:

[0009] 100-110 parts of carboxylated styrene butadiene latex

[0010] Composite modified hollow glass microspheres 5-10 parts

[0011] Modified filler 4-6 parts

[0012] Zinc oxide 1-1.5 parts

[0013] 1-3 parts of antioxidant

[0014] 3-5 parts of crosslinking agent

[0015] 1-3 parts of accelerator;

[0016] The accelerator is triallyl isocyanurate (TAIC);

[0017] The cross-linking agent is dicumyl peroxide (DCP);

[0018] The antioxidant is 4,4'-bis(α,α-dimethylbenzyl)diphenylamine;

[0019] As a preferred technical solution of the present invention, the modified filler is a mixture of montmorillonite modified by a silane coupling agent and calcium carbonate.

[0020] As a preferred technical solution of the present invention, the carboxylated styrene butadiene composite latex is composited by sorbic acid, carboxymethyl chitosan and carboxylated styrene butadiene latex;

[0021] The preparation method of the composite modified hollow glass microspheres comprises the following steps:

[0022] S1, placing eugenol, cysteine ​​and a photoinitiator in a reactor, reacting under ultraviolet light, adding an ethanol solution and stirring and mixing to obtain a carboxyl-eugenol solution;

[0023] S2. Add NHS to the carboxyl-eugenol solution and stir to mix, then add amino-modified hollow glass microspheres and EDC and stir to mix, heat to react, and then freeze-dry to obtain composite modified hollow glass microspheres.

[0024] Furthermore, the present invention allows eugenol and cysteine ​​to undergo a thiol-ene click reaction under ultraviolet irradiation and the action of a photoinitiator, thereby further introducing carboxyl and hydroxyl groups into the structure of eugenol. The carboxyl groups in the carboxyl-eugenol solution can undergo an acetylation reaction with the amino groups on the amino-modified hollow glass microspheres, so that the composite modified hollow glass microspheres are introduced with the eugenol structure, thereby increasing their stability. The composite modified hollow glass microspheres contain a large number of active functional groups such as amino, carboxyl, hydroxyl and vinyl groups, thereby significantly increasing the compatibility between the hollow glass microspheres and the matrix.

[0025] As a preferred technical solution of the present invention, in step S1, the molar ratio of eugenol to cysteine ​​is 1:10-12; the mass ratio of the photoinitiator, eugenol and ethanol solution is 1-1.3:3-5:150-180, the reaction is at 30-40°C and the reaction time is 12-15h; the photoinitiator is 4-dimethylaminopyridine; the mass fraction of the ethanol solution is 35-50%;

[0026] In step S2, the heating reaction is carried out at 40-60° C. for 8-10 hours; the mass ratio of the carboxyl-eugenol solution, NHS, amino-modified hollow glass microspheres and EDC is 90:5.5-6.5:5-6:9-10; the NHS is N-hydroxysuccinimide; and the EDC is 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, which is used to activate the carboxyl groups on the carboxyl-eugenol solution.

[0027] As a preferred technical solution of the present invention, montmorillonite needs to be pretreated before use: deionized water is added to montmorillonite particles and stirred for 10 hours, a montmorillonite suspension with a mass fraction of 5% is prepared, and the suspension is allowed to stand at room temperature for 30 hours. After the upper liquid is centrifuged, the solid is soaked in 30% hydrogen peroxide with a mass fraction for 20 hours, washed three times with deionized water, and dried to obtain montmorillonite.

[0028] As a preferred technical solution of the present invention, the preparation method of the modified filler comprises the following steps:

[0029] After the silane coupling agent, ethanol and deionized water are stirred and mixed, montmorillonite and calcium carbonate are slowly added under stirring and mixed evenly, and then dried and ground to modify the filler.

[0030] As a preferred technical solution of the present invention, the mass ratio of the silane coupling agent, ethanol, deionized water, montmorillonite and calcium carbonate is 5-7:20-22:3-5:0.5-0.8:1.0-1.5; the mixing temperature is 65-80°C and the mixing time is 1-1.5h.

[0031] As a preferred technical solution of the present invention, the preparation method of the carboxylated styrene-butadiene composite latex comprises the following steps:

[0032] After ultrasonically mixing carboxymethyl chitosan, sorbic acid and deionized water, carboxylated styrene butadiene latex is added thereto and stirred at high speed, vacuum degassed and dried to obtain carboxylated styrene butadiene composite latex.

[0033] As a preferred technical solution of the present invention, the mass ratio of carboxymethyl chitosan, sorbic acid, deionized water and carboxylated styrene butadiene latex is 1.0-1.3:0.2-0.4:150:5-5.5; the ultrasonic mixing is 300-400W and the ultrasonication is 10-15min; the vacuum degassing time is 1-2h; the high-speed stirring is 1000-1200r / min and the stirring is 20-30min; the solid content of the carboxylated styrene butadiene latex is 50-60%; in the present invention, carboxymethyl chitosan and sorbic acid are uniformly dispersed in the carboxylated styrene butadiene latex under the action of ultrasound, and under the action of ultrasound, the agglomeration of carboxymethyl chitosan is reduced, and the contact between carboxymethyl chitosan, sorbic acid and carboxylated styrene butadiene latex is promoted, so that the carboxymethyl chitosan, sorbic acid and carboxylated styrene butadiene latex form a cross-linked network structure with non-covalent interaction, which is beneficial to the improvement of the cross-linking density of the material system.

[0034] Furthermore, sorbic acid, as an unsaturated fatty acid, can undergo a grafting reaction with the carbon-carbon double bonds on the carboxylated styrene butadiene latex material system chain, and its carboxyl group can form a hydrogen bond with the hydroxyl group in the hollow glass microspheres. These characteristics make the addition of sorbic acid play a key role in enhancing the interaction between the hollow glass microspheres and the rubber, and effectively improve the dispersion performance of the hollow glass microspheres in the system. Furthermore, this improvement promotes the expansion of the contact area between the filler and the carboxylated styrene butadiene latex, which has a positive significance for improving the overall performance of the carboxylated styrene butadiene latex material.

[0035] Furthermore, in the carboxylated styrene butadiene latex material, the addition of zinc oxide as a vulcanization accelerator can effectively promote the vulcanization and activity process of the material. At the same time, zinc oxide also has the function of a reinforcing agent, which plays a significant reinforcing role on the carboxylated styrene butadiene latex. In addition, the zinc ions in zinc oxide form a complex with carboxyl, amino and hydroxyl groups, which plays a cross-linking role in the carboxymethyl chitosan / carboxylated styrene butadiene latex network structure, thereby significantly enhancing the stability of the entire network structure.

[0036] Furthermore, the present invention prepares carboxylated styrene butadiene composite latex by compounding carboxymethyl chitosan, sorbic acid and carboxylated styrene butadiene latex, so that carboxyl groups, amino groups and hydroxyl groups are exposed in the carboxylated styrene butadiene composite latex, and the composite modified hollow glass microspheres also contain carboxyl groups, amino groups and hydroxyl functional groups. Through the interaction between these functional groups, the compatibility of the hollow glass microspheres in the matrix is ​​significantly increased.

[0037] As a preferred technical solution of the present invention, the preparation method of the amino-modified hollow glass microspheres comprises the following steps:

[0038] S21, adding the hollow glass microspheres to the hydroxide solution, reflux stirring for reaction, washing, and drying to obtain pretreated hollow glass microspheres;

[0039] S22, stirring and mixing the solvent, the organotin catalyst and the coupling agent to obtain a mixed solution;

[0040] S23, slowly dropping the mixed solution onto the pretreated hollow glass microspheres, and after ultrasonic treatment, reacting to obtain amino-modified hollow glass microspheres.

[0041] As a preferred technical solution of the present invention, in step S21, the reflux stirring reaction is 80-90°C and refluxes for 1-1.5h; the mass fraction of the hydroxide solution is 1.5-2.0%; the amount ratio of the hollow glass microspheres to the hydroxide solution is 3.0-4.5g:100mL; the present invention forms an irregular "pit-like" structure on the surface of the hollow glass microsphere matrix through the chemical reaction between the hydroxide solution and the surface of the hollow glass microsphere matrix. Subsequently, a coupling agent is introduced to the surface to change its surface properties so that the grooves on the surface play a role similar to "anchoring", thereby enhancing the close bonding between the components of the composite material. In addition, the surface of the amino-modified hollow glass microspheres will generate many related active groups, such as amino, carboxyl, and hydroxyl groups, which can effectively attract organic components to attach to their surface, thereby improving the compatibility of the hollow glass microspheres with the matrix.

[0042] As a preferred technical solution of the present invention, in step S22, the stirring and mixing is performed at a speed of 1200-1600 r / min for 15-20 min;

[0043] As a preferred technical solution of the present invention, in step S22, the mass ratio of the pretreated hollow glass microspheres, the solvent, the coupling agent and the organic tin catalyst is 35-42:40-55:3-5:0.08-0.12; the solvent is a mixture of ethanol and ethyl acetate in a mass ratio of 2:1; the organic tin catalyst is one or more of dibutyltin dilaurate, dibutyltin dichloride and tributyltin chloride; the coupling agent is a mixture of coupling agent A and coupling agent B in a mass ratio of 3-3.5:1; the coupling agent A is an amino-containing coupling agent; the amino-containing coupling agent is γ-aminopropyltriethoxysilane and N-(β-aminoethyl)-γ-amino One or two of propyl triethoxysilane; N-(β-aminoethyl)-γ-aminopropyl triethoxysilane is also called silane coupling agent KH-791; the coupling agent B is a vinyl-containing coupling agent, and the vinyl-containing coupling agent is one or two of vinyl trimethoxysilane and vinyl triethoxysilane; the present invention modifies the surface of the pretreated hollow glass microspheres by combining a vinyl-containing coupling agent and an amino-containing coupling agent, so that the surface of the pretreated hollow glass microspheres has active amino groups and vinyl groups, the amino groups can react with carboxyl groups under the action of a catalyst and an activator to undergo acetylation, and the vinyl groups are increased to further improve the compatibility of the hollow glass microspheres with the matrix.

[0044] As a preferred technical solution of the present invention, in step S23, the slow dripping time is 45-60 min; the ultrasonic treatment is at 30-40°C, 300-500W power, and 5-8 min; the reaction is at 30-40r / min, 80-90°C, and 2-4h.

[0045] The present invention discloses a method for preparing the modified carboxylated styrene-butadiene latex, which comprises the following steps:

[0046] After mixing carboxylated styrene butadiene composite latex, composite modified hollow glass microspheres and zinc oxide, adding modified filler, antioxidant, crosslinking agent and accelerator for mixing and vulcanization, and after secondary vulcanization, a modified carboxylated styrene butadiene latex is obtained;

[0047] The mixing and vulcanization is carried out at 150-170°C, 40-60MPa, and mixing time is 30-45min; the secondary vulcanization is carried out at 150°C and vulcanization time is 3-4h.

[0048] The invention discloses application of modified carboxyl styrene butadiene latex in papermaking, textile and construction.

[0049] Beneficial effects of the present invention:

[0050] The invention introduces a large amount of amino groups, carboxyl groups and hydroxyl groups into carboxylated styrene butadiene composite latex and composite modified hollow glass microspheres at the same time, and through the hydrogen bond interaction between these active groups, the dispersibility of the hollow glass microspheres in the system is significantly improved, and a tangled cross-linked structure is formed to enhance the interface bonding ability between the two. At the same time, the two contain a large amount of unsaturated double bonds, and the composite modified hollow glass microspheres participate in the free radical reaction of the carboxylated styrene butadiene latex system, and can be better combined with the matrix in the carboxylated styrene butadiene latex system; in addition, the mechanical properties and thermal stability of the carboxylated styrene butadiene latex material can be significantly improved through the introduced benzene ring structure, hollow glass microspheres, zinc oxide and modified fillers. DETAILED DESCRIPTION

[0051] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention are described in detail below in combination with the embodiments.

[0052] Embodiment of the present invention:

[0053] A modified carboxyl styrene-butadiene latex comprises the following components in parts by weight:

[0054] 100-110 parts of carboxylated styrene butadiene latex

[0055] Composite modified hollow glass microspheres 5-10 parts

[0056] Modified filler 4-6 parts

[0057] Zinc oxide 1-1.5 parts

[0058] 1-3 parts of antioxidant

[0059] DCP 3-5 parts

[0060] TAIC 1-3 parts;

[0061] The antioxidant is 4,4'-bis(α,α-dimethylbenzyl)diphenylamine.

[0062] The preparation method of the composite modified hollow glass microspheres comprises the following steps:

[0063] S1. Place eugenol, cysteine ​​and 4-dimethylaminopyridine in a reactor, react at 30-40° C. for 12-15 hours under ultraviolet light, add 35-50% ethanol solution by mass, stir and mix, and obtain a carboxyl-eugenol solution; wherein the molar ratio of eugenol to cysteine ​​is 1:10-12; the mass ratio of 4-dimethylaminopyridine, eugenol and ethanol solution is 1-1.3:3-5:150-180;

[0064] S2. Add NHS to the carboxyl-eugenol solution and stir to mix, then add amino-modified hollow glass microspheres and EDC and stir to mix, react at 40-60° C. for 8-10 hours, then freeze-dry to obtain composite modified hollow glass microspheres; wherein the mass ratio of the carboxyl-eugenol solution, NHS, amino-modified hollow glass microspheres and EDC is 90:5.5-6.5:5-6:9-10; the NHS is N-hydroxysuccinimide; and the EDC is 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride.

[0065] The preparation method of the amino-modified hollow glass microspheres comprises the following steps:

[0066] S21, adding the hollow glass microspheres to a hydroxide solution with a mass fraction of 1.5-2.0%, washing at 80-90° C., refluxing for 1-1.5 h, and drying to obtain pretreated hollow glass microspheres; wherein the amount ratio of the hollow glass microspheres to the hydroxide solution is 3.0-4.5 g: 100 mL;

[0067] S22, stirring the solvent, the organotin catalyst and the coupling agent at a speed of 1200-1600 r / min for 15-20 min to obtain a mixed solution; wherein the coupling agent is a mixture of N-(β-aminoethyl)-γ-aminopropyltriethoxysilane and vinyltrimethoxysilane in a mass ratio of 3-3.5:1;

[0068] S23. Slowly add the mixed liquid to the pretreated hollow glass microspheres within 45-60 minutes, and ultrasonicate for 5-8 minutes at 30-40°C and 300-500W power, and then react for 2-4 hours at 30-40r / min and 80-90°C to obtain amino-modified hollow glass microspheres; wherein the mass ratio of the pretreated hollow glass microspheres, the solvent, the coupling agent and dibutyltin dilaurate is 35-42:40-55:3-5:0.08-0.12; and the solvent is a mixture of ethanol and ethyl acetate in a mass ratio of 2:1.

[0069] The preparation method of the modified filler comprises the following steps:

[0070] After mixing silane coupling agent KH560, ethanol and deionized water, montmorillonite and calcium carbonate are slowly added at 65-80°C and mixed for 1-1.5 hours under stirring, and then dried and ground to modify the filler; wherein the mass ratio of the silane coupling agent, ethanol, deionized water, montmorillonite and calcium carbonate is 5-7:20-22:3-5:0.5-0.8:1.0-1.5.

[0071] The preparation method of the carboxylated styrene butadiene composite latex comprises the following steps:

[0072] After ultrasonicating carboxymethyl chitosan, sorbic acid and deionized water at 300-400W for 10-15min, add carboxylated styrene butadiene latex with a solid content of 50-60%, stir at 1000-1200r / min for 20-30min, vacuum degassing for 1-2h, and drying to obtain carboxylated styrene butadiene composite latex; wherein the mass ratio of carboxymethyl chitosan, sorbic acid, deionized water and carboxylated styrene butadiene latex is 1.0-1.3:0.2-0.4:150:5-5.5.

[0073] The preparation method of the modified carboxyl styrene-butadiene latex comprises the following steps:

[0074] After the carboxylated styrene butadiene composite latex, the composite modified hollow glass microspheres and zinc oxide are stirred and mixed, modified fillers, antioxidants, crosslinking agents and accelerators are added and kneaded for 30-45 minutes at a temperature of 150-170° C. and a pressure of 40-60 MPa. After secondary vulcanization at 150° C. and 3-4 hours, modified carboxylated styrene butadiene latex is obtained. Example 1

[0075] A modified carboxyl styrene-butadiene latex comprises the following components in parts by weight:

[0076] 100 parts of carboxylated styrene butadiene latex

[0077] 5 parts of composite modified hollow glass microspheres

[0078] 4 parts of modified filler

[0079] 1 part zinc oxide

[0080] 1 part antioxidant

[0081] DCP 3 copies

[0082] TAIC 1;

[0083] The antioxidant is 4,4'-bis(α,α-dimethylbenzyl)diphenylamine.

[0084] The preparation method of the composite modified hollow glass microspheres comprises the following steps:

[0085] S1. Place eugenol, cysteine ​​and 4-dimethylaminopyridine in a reactor, react at 30°C for 12 hours under ultraviolet light, add 35% ethanol solution by mass, stir and mix, and obtain a carboxyl-eugenol solution; wherein the molar ratio of eugenol to cysteine ​​is 1:10; the mass ratio of 4-dimethylaminopyridine, eugenol and ethanol solution is 1:3:150;

[0086] S2. Add NHS to the carboxyl-eugenol solution and stir to mix, then add amino-modified hollow glass microspheres and EDC and stir to mix, react at 40° C. for 8 hours, and then freeze-dry to obtain composite modified hollow glass microspheres; wherein the mass ratio of the carboxyl-eugenol solution, NHS, amino-modified hollow glass microspheres and EDC is 90:5.5:5:9; the NHS is N-hydroxysuccinimide; and the EDC is 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride.

[0087] The preparation method of the amino-modified hollow glass microspheres comprises the following steps:

[0088] S21, adding the hollow glass microspheres to a hydroxide solution with a mass fraction of 1.5%, washing at 80° C., refluxing for 1 h, and drying to obtain pretreated hollow glass microspheres; wherein the amount ratio of the hollow glass microspheres to the hydroxide solution is 3.0 g: 100 mL;

[0089] S22, stirring the solvent, the organotin catalyst and the coupling agent at a speed of 1200 r / min for 15 minutes to obtain a mixed solution; wherein the coupling agent is a mixture of N-(β-aminoethyl)-γ-aminopropyltriethoxysilane and vinyltrimethoxysilane in a mass ratio of 3:1;

[0090] S23. Slowly add the mixed liquid to the pretreated hollow glass microspheres within 45 minutes, and after ultrasonication at 30°C and 300 W power for 5 minutes, react at 30 r / min and 80°C for 2 hours to obtain amino-modified hollow glass microspheres; wherein the mass ratio of the pretreated hollow glass microspheres, solvent, coupling agent and dibutyltin dilaurate is 35:40:3:0.08; and the solvent is a mixture of ethanol and ethyl acetate in a mass ratio of 2:1.

[0091] The preparation method of the modified filler comprises the following steps:

[0092] After stirring and mixing silane coupling agent KH560, ethanol and deionized water, montmorillonite and calcium carbonate are slowly added at 65° C. and mixed for 1 hour under stirring, and then dried and ground to modify the filler; wherein the mass ratio of the silane coupling agent, ethanol, deionized water, montmorillonite and calcium carbonate is 5:20:3:0.5:1.0.

[0093] The preparation method of the carboxylated styrene butadiene composite latex comprises the following steps:

[0094] After carboxymethyl chitosan, sorbic acid and deionized water were ultrasonicated at 300W for 10 minutes, carboxylated styrene butadiene latex with a solid content of 50% was added, and the mixture was stirred at 1000r / min for 20 minutes. The mixture was vacuum degassed for 1 hour and dried to obtain carboxylated styrene butadiene composite latex. The mass ratio of carboxymethyl chitosan, sorbic acid, deionized water and carboxylated styrene butadiene latex was 1.0:0.2:150:5.

[0095] The preparation method of the modified carboxyl styrene-butadiene latex comprises the following steps:

[0096] After the carboxylated styrene butadiene composite latex, the composite modified hollow glass microspheres and zinc oxide are stirred and mixed, modified fillers, antioxidants, crosslinking agents and accelerators are added and kneaded for 30 minutes at a temperature of 150° C. and a pressure of 40 MPa. After secondary vulcanization at 150° C. for 3 hours, modified carboxylated styrene butadiene latex is obtained. Example 2

[0097] A modified carboxyl styrene-butadiene latex comprises the following components in parts by weight:

[0098] 105 parts of carboxylated styrene butadiene latex

[0099] 8 parts of composite modified hollow glass microspheres

[0100] 5 parts of modified filler

[0101] 1.2 parts of zinc oxide

[0102] 2 parts of antioxidant

[0103] DCP 4 copies

[0104] 2 TAIC;

[0105] The antioxidant is 4,4'-bis(α,α-dimethylbenzyl)diphenylamine.

[0106] The preparation method of the composite modified hollow glass microspheres comprises the following steps:

[0107] S1. Place eugenol, cysteine ​​and 4-dimethylaminopyridine in a reactor, react at 35°C for 14 hours under ultraviolet light, add 42% ethanol solution by mass, stir and mix, and obtain a carboxyl-eugenol solution; wherein the molar ratio of eugenol to cysteine ​​is 1:11; the mass ratio of 4-dimethylaminopyridine, eugenol and ethanol solution is 1.2:4:165;

[0108] S2. Add NHS to the carboxyl-eugenol solution and stir to mix, then add amino-modified hollow glass microspheres and EDC and stir to mix, react at 50° C. for 9 hours, then freeze-dry to obtain composite modified hollow glass microspheres; wherein the mass ratio of the carboxyl-eugenol solution, NHS, amino-modified hollow glass microspheres and EDC is 90:6:5.5:9.5; the NHS is N-hydroxysuccinimide; and the EDC is 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride.

[0109] The preparation method of the amino-modified hollow glass microspheres comprises the following steps:

[0110] S21, adding the hollow glass microspheres to a hydroxide solution with a mass fraction of 1.8%, washing at 85° C., refluxing for 1.2 h, and drying to obtain pretreated hollow glass microspheres; wherein the amount ratio of the hollow glass microspheres to the hydroxide solution is 3.8 g: 100 mL;

[0111] S22, stirring the solvent, the organotin catalyst and the coupling agent at a speed of 1400 r / min for 18 minutes to obtain a mixed solution; wherein the coupling agent is a mixture of N-(β-aminoethyl)-γ-aminopropyltriethoxysilane and vinyltrimethoxysilane in a mass ratio of 3.2:1;

[0112] S23. Slowly add the mixed liquid to the pretreated hollow glass microspheres within 52 minutes, and after ultrasonication at 35°C and 400 W power for 6 minutes, react at 35 r / min and 85°C for 3 hours to obtain amino-modified hollow glass microspheres; wherein the mass ratio of the pretreated hollow glass microspheres, solvent, coupling agent and dibutyltin dilaurate is 38:48:4:0.1; and the solvent is a mixture of ethanol and ethyl acetate in a mass ratio of 2:1.

[0113] The preparation method of the modified filler comprises the following steps:

[0114] After the silane coupling agent KH560, ethanol and deionized water are stirred and mixed, montmorillonite and calcium carbonate are slowly added at 73° C. and mixed for 1.2 hours under stirring, and then dried and ground to modify the filler; wherein the mass ratio of the silane coupling agent, ethanol, deionized water, montmorillonite and calcium carbonate is 6:21:4:0.6:1.2.

[0115] The preparation method of the carboxylated styrene butadiene composite latex comprises the following steps:

[0116] After carboxymethyl chitosan, sorbic acid and deionized water were ultrasonically treated at 350W for 12 minutes, carboxylated styrene butadiene latex with a solid content of 55% was added, and the mixture was stirred at 1100r / min for 25 minutes, vacuum degassed for 1.5 hours, and dried to obtain carboxylated styrene butadiene composite latex; wherein the mass ratio of carboxymethyl chitosan, sorbic acid, deionized water and carboxylated styrene butadiene latex was 1.2:0.3:150:5.2.

[0117] The preparation method of the modified carboxyl styrene-butadiene latex comprises the following steps:

[0118] After the carboxylated styrene butadiene composite latex, the composite modified hollow glass microspheres and zinc oxide were stirred and mixed, modified fillers, antioxidants, crosslinking agents and accelerators were added and mixed at 160°C and 50MPa for 38 minutes. After secondary vulcanization at 150°C for 3.5 hours, modified carboxylated styrene butadiene latex was obtained. Example 3

[0119] A modified carboxyl styrene-butadiene latex comprises the following components in parts by weight:

[0120] 110 parts of carboxylated styrene butadiene latex

[0121] 10 parts of composite modified hollow glass microspheres

[0122] 6 parts of modified filler

[0123] 1.5 parts zinc oxide

[0124] 3 parts of antioxidant

[0125] DCP 5 copies

[0126] 3 parts of TAIC;

[0127] The antioxidant is 4,4'-bis(α,α-dimethylbenzyl)diphenylamine.

[0128] The preparation method of the composite modified hollow glass microspheres comprises the following steps:

[0129] S1. Place eugenol, cysteine ​​and 4-dimethylaminopyridine in a reactor, react at 40°C for 15 hours under ultraviolet light, add 50% ethanol solution by mass, stir and mix, and obtain a carboxyl-eugenol solution; wherein the molar ratio of eugenol to cysteine ​​is 1:12; the mass ratio of 4-dimethylaminopyridine, eugenol and ethanol solution is 1.3:5:180;

[0130] S2. Add NHS to the carboxyl-eugenol solution and stir to mix, then add amino-modified hollow glass microspheres and EDC and stir to mix, react at 60° C. for 10 hours, then freeze-dry to obtain composite modified hollow glass microspheres; wherein the mass ratio of the carboxyl-eugenol solution, NHS, amino-modified hollow glass microspheres and EDC is 90:6.5:6:10; the NHS is N-hydroxysuccinimide; and the EDC is 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride.

[0131] The preparation method of the amino-modified hollow glass microspheres comprises the following steps:

[0132] S21, adding the hollow glass microspheres to a hydroxide solution with a mass fraction of 2.0%, washing at 90° C., refluxing for 1.5 h, and drying to obtain pretreated hollow glass microspheres; wherein the amount ratio of the hollow glass microspheres to the hydroxide solution is 4.5 g:100 mL;

[0133] S22, stirring the solvent, the organotin catalyst and the coupling agent at a speed of 1600 r / min for 20 minutes to obtain a mixed solution; wherein the coupling agent is a mixture of N-(β-aminoethyl)-γ-aminopropyltriethoxysilane and vinyltrimethoxysilane in a mass ratio of 3.5:1;

[0134] S23. Slowly add the mixed liquid to the pretreated hollow glass microspheres within 60 minutes, and after ultrasonic treatment at 40°C and 500 W power for 8 minutes, react at 40 r / min and 90°C for 4 hours to obtain amino-modified hollow glass microspheres; wherein the mass ratio of the pretreated hollow glass microspheres, solvent, coupling agent and dibutyltin dilaurate is 42:55:5:0.12; and the solvent is a mixture of ethanol and ethyl acetate in a mass ratio of 2:1.

[0135] The preparation method of the modified filler comprises the following steps:

[0136] After stirring and mixing silane coupling agent KH560, ethanol and deionized water, montmorillonite and calcium carbonate are slowly added at 80° C. and mixed for 1.5 hours under stirring, and then dried and ground to modify the filler; wherein the mass ratio of the silane coupling agent, ethanol, deionized water, montmorillonite and calcium carbonate is 7:22:5:0.8:1.5.

[0137] The preparation method of the carboxylated styrene butadiene composite latex comprises the following steps:

[0138] After carboxymethyl chitosan, sorbic acid and deionized water were ultrasonicated at 400 W for 15 min, carboxylated styrene butadiene latex with a solid content of 60% was added, and the mixture was stirred at 1200 r / min for 30 min. The mixture was vacuum degassed for 2 h and dried to obtain a carboxylated styrene butadiene composite latex. The mass ratio of carboxymethyl chitosan, sorbic acid, deionized water and carboxylated styrene butadiene latex was 1.3:0.4:150:5.5.

[0139] The preparation method of the modified carboxyl styrene-butadiene latex comprises the following steps:

[0140] After the carboxylated styrene butadiene composite latex, the composite modified hollow glass microspheres and zinc oxide are stirred and mixed, modified fillers, antioxidants, crosslinking agents and accelerators are added and mixed at 170°C and 60MPa for 45 minutes. After secondary vulcanization at 150°C for 4 hours, modified carboxylated styrene butadiene latex is obtained.

[0141] Comparative Example 1

[0142] Compared with Example 2, the difference is that methyl allyl alcohol replaces eugenol, and the other components, preparation steps and parameters are the same.

[0143] Comparative Example 2

[0144] Compared with Example 2, the difference is that the composite modified hollow glass microspheres are not modified, hollow glass microspheres are used instead of the composite modified hollow glass microspheres, and the other components, preparation steps and parameters are the same.

[0145] Comparative Example 3

[0146] Compared with Example 2, the difference is that in step S22, the coupling agent is prepared by mixing N-(β-aminoethyl)-γ-aminopropyltriethoxysilane and vinyltrimethoxysilane in a mass ratio of 2:1, and the other components, preparation steps and parameters are the same.

[0147] Comparative Example 4

[0148] Compared with Example 2, the difference is that in step S22, the coupling agent is N-(β-aminoethyl)-γ-aminopropyltriethoxysilane, and the other components, preparation steps and parameters are the same.

[0149] Comparative Example 5

[0150] Compared with Example 2, the difference is that carboxymethyl chitosan is not used, and the other components, preparation steps and parameters are the same.

[0151] Comparative Example 6

[0152] Compared with Example 2, the difference is that sorbic acid is not used, and the other components, preparation steps and parameters are the same.

[0153] Comparative Example 7

[0154] Compared with Example 2, the difference is that carboxymethyl chitosan is not used in the preparation of carboxylated styrene butadiene composite latex, but is added in the preparation of modified carboxylated styrene butadiene latex; as follows:

[0155] The preparation method of modified carboxyl styrene butadiene latex comprises the following steps:

[0156] After the carboxylated styrene butadiene composite latex, the composite modified hollow glass microspheres and zinc oxide were stirred and mixed, modified fillers, carboxymethyl chitosan, antioxidants, crosslinking agents and accelerators were added and mixed at 150°C and 40MPa for 30 minutes. After secondary vulcanization at 150°C for 3 hours, modified carboxylated styrene butadiene latex was obtained.

[0157] The remaining components, preparation steps and parameters were the same.

[0158] The modified carboxylated styrene butadiene latex prepared in Examples 1-3 and Comparative Examples 1-7 were subjected to the following tests: tensile strength and elongation at break were tested with reference to GB / T8655-2019; weather resistance was tested with reference to GB / T1865-2009; the test results are shown in Table 1.

[0159] Table 1

[0160] Tensile strength (MPa) Elongation at break (%) Weather resistance Example 1 37.8 630 No significant changes Example 2 38.0 634 No significant changes Example 3 37.9 632 No significant changes Comparative Example 1 35.7 591 Small part turns yellow Comparative Example 2 27.2 442 Most of them turn yellow Comparative Example 3 31.4 519 Small part turns yellow Comparative Example 4 30.2 493 Small part turns yellow Comparative Example 5 29.0 479 Partially yellowed Comparative Example 6 32.5 534 Small part turns yellow Comparative Example 7 30.8 509 Partially yellowed

[0161] From the test results in Table 1, it can be seen that compared with Comparative Examples 1-7, the tensile strength, elongation at break and weather resistance of the modified carboxylated styrene butadiene latex prepared in Examples 1-3 of the present invention are significantly better than those of Comparative Examples 1-7.

[0162] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A modified carboxylated styrene-butadiene latex, characterized in that: The components include the following by weight: 100-110 parts of carboxylated styrene butadiene latex Composite modified hollow glass microspheres 5-10 parts 4-6 parts of modified filler Zinc oxide 1-1.5 parts 1-3 parts of antioxidant 3-5 parts of crosslinking agent 1-3 parts of accelerator; The modified filler is a mixture of montmorillonite modified by a silane coupling agent and calcium carbonate; The carboxylated styrene butadiene composite latex is composited from sorbic acid, carboxymethyl chitosan and carboxylated styrene butadiene latex; The preparation method of the composite modified hollow glass microspheres comprises the following steps: S1, placing eugenol, cysteine ​​and a photoinitiator in a reactor, reacting under ultraviolet light, adding an ethanol solution and stirring and mixing to obtain a carboxyl-eugenol solution; S2. Add NHS to the carboxyl-eugenol solution and stir to mix, then add amino-modified hollow glass microspheres and EDC and stir to mix, heat to react, and then freeze-dry to obtain composite modified hollow glass microspheres.

2. A modified carboxylated styrene-butadiene latex according to claim 1, characterized in that: In step S1, the molar ratio of eugenol to cysteine ​​is 1:10-12; the mass ratio of the photoinitiator, eugenol and ethanol solution is 1-1.3:3-5:150-180, the reaction is at 30-40°C and the reaction time is 12-15h; the photoinitiator is 4-dimethylaminopyridine; the mass fraction of the ethanol solution is 35-50%; In step S2, the heating reaction is carried out at 40-60° C. for 8-10 hours; the mass ratio of the carboxyl-eugenol solution, NHS, amino-modified hollow glass microspheres and EDC is 90:5.5-6.5:5-6:9-10; the NHS is N-hydroxysuccinimide; and the EDC is 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride.

3. A modified carboxylated styrene-butadiene latex according to claim 1, characterized in that: The preparation method of the modified filler comprises the following steps: After the silane coupling agent, ethanol and deionized water are stirred and mixed, montmorillonite and calcium carbonate are slowly added under stirring and mixed evenly, and then dried and ground to modify the filler.

4. A modified carboxylated styrene-butadiene latex according to claim 3, characterized in that: The mass ratio of the silane coupling agent, ethanol, deionized water, montmorillonite and calcium carbonate is 5-7:20-22:3-5:0.5-0.8:1.0-1.5; the mixing temperature is 65-80° C. and the mixing time is 1-1.5 hours.

5. The modified carboxylated styrene-butadiene latex according to claim 1, characterized in that: The preparation method of the carboxylated styrene butadiene composite latex comprises the following steps: After ultrasonically mixing carboxymethyl chitosan, sorbic acid and deionized water, carboxylated styrene butadiene latex is added thereto and stirred at high speed, vacuum degassed and dried to obtain carboxylated styrene butadiene composite latex.

6. A modified carboxylated styrene-butadiene latex according to claim 5, characterized in that: The mass ratio of carboxymethyl chitosan, sorbic acid, deionized water and carboxylated styrene butadiene latex is 1.0-1.3:0.2-0.4:150:5-5.5; the ultrasonic mixing is 300-400W and the ultrasonic treatment is 10-15min; the vacuum degassing time is 1-2h; the high-speed stirring is 1000-1200r / min and the stirring is 20-30min; the solid content of the carboxylated styrene butadiene latex is 50-60%.

7. The modified carboxylated styrene-butadiene latex according to claim 1, characterized in that: The preparation method of the amino-modified hollow glass microspheres comprises the following steps: S21, adding the hollow glass microspheres to the hydroxide solution, reflux stirring for reaction, washing, and drying to obtain pretreated hollow glass microspheres; S22, stirring and mixing the solvent, the organotin catalyst and the coupling agent to obtain a mixed solution; S23, slowly dropping the mixed solution onto the pretreated hollow glass microspheres, and after ultrasonic treatment, reacting to obtain amino-modified hollow glass microspheres.

8. A modified carboxylated styrene-butadiene latex according to claim 7, characterized in that: In step S21, the reflux stirring reaction is 80-90° C., reflux for 1-1.5 hours; the mass fraction of the hydroxide solution is 1.5-2.0%; the dosage ratio of the hollow glass microspheres to the hydroxide solution is 3.0-4.5 g: 100 mL; In step S22, the stirring and mixing is performed at a speed of 1200-1600 r / min for 15-20 min; In step S22, the mass ratio of the pretreated hollow glass microspheres, the solvent, the coupling agent and the organic tin catalyst is 35-42:40-55:3-5:0.08-0.12; the solvent is a mixture of ethanol and ethyl acetate in a mass ratio of 2:1; the organic tin catalyst is one or more of dibutyltin dilaurate, dibutyltin dichloride and tributyltin chloride; the coupling agent is a mixture of coupling agent A and coupling agent B in a mass ratio of 3-3.5:1; In step S23, the slow dripping time is 45-60 min; the ultrasonic treatment is carried out at 30-40°C, 300-500 W power, and 5-8 min; the reaction is carried out at 30-40 r / min, 80-90°C, and 2-4 h.

9. A method for preparing the modified carboxylated styrene-butadiene latex according to any one of claims 1 to 8, characterized in that: The preparation method comprises the following steps: After mixing carboxylated styrene butadiene composite latex, composite modified hollow glass microspheres and zinc oxide, adding modified filler, antioxidant, crosslinking agent and accelerator for mixing and vulcanization, and after secondary vulcanization, a modified carboxylated styrene butadiene latex is obtained; The mixing and vulcanization is carried out at 150-170°C, 40-60MPa, and the mixing time is 30-45min; the secondary vulcanization is carried out at 150°C and the vulcanization time is 3-4h.

10. Use of the modified carboxylated styrene-butadiene latex as claimed in any one of claims 1 to 7 in papermaking, textiles and construction.