阅读说明：本技术 一种高强度的石墨烯增韧改性聚苯乙烯材料及其制法 (High-strength graphene toughening modified polystyrene material and preparation method thereof ) 是由 丁文华 于 2020-08-10 设计创作，主要内容包括：本发明涉及聚苯乙烯材料领域,且公开了一种高强度的石墨烯增韧改性聚苯乙烯材料,羟基化石墨烯大量的羟基,以溴酰胺功能化石墨烯作为大分子引发剂,溴酰胺基团中的溴原子作为单电子转移活性位点,通过单电子转移活性自由基聚合,高效引发苯乙烯在石墨烯表面原位聚合,从而得到石墨烯化学共价接枝聚苯乙烯,通过化学键修饰,使石墨烯均匀分散在聚苯乙烯的基体中,化学键的键能远比石墨烯纳米粒子之间的范德华力强,从而改善了石墨烯与聚苯乙烯的界面相容性,避免了石墨烯纳米粒子团聚和聚集的现象,分散均匀的石墨烯显著提高了聚苯乙烯的拉伸强度和抗冲击强度等机械性能。(The invention relates to the field of polystyrene materials, and discloses a high-strength graphene toughening modified polystyrene material, which is prepared by hydroxylating a large amount of hydroxyl groups of graphene, bromoamide functionalized graphene is used as a macromolecular initiator, bromine atoms in bromoamide groups are used as single electron transfer active sites, the styrene is efficiently initiated to be polymerized on the surface of the graphene in situ by single electron transfer active free radical polymerization, so as to obtain graphene chemically covalent grafted polystyrene, the graphene is uniformly dispersed in the matrix of the polystyrene through chemical bond modification, the bond energy of the chemical bond is far stronger than the van der Waals force among graphene nano particles, therefore, the interface compatibility of the graphene and the polystyrene is improved, the phenomena of agglomeration and aggregation of graphene nano particles are avoided, and the mechanical properties such as tensile strength, impact strength and the like of the polystyrene are remarkably improved by the uniformly dispersed graphene.)

1. A high-strength graphene toughening modified polystyrene material is characterized in that: the preparation method of the high-strength graphene toughened and modified polystyrene material comprises the following steps:

(1) adding hydroxylated graphene into an ethanol solvent, placing the mixture into an ultrasonic treatment instrument for ultrasonic dispersion, adding triethanolamine and 3-aminopropyltriethoxysilane, heating to 40-80 ℃, stirring for reaction for 6-12h, filtering, washing and drying to prepare amino functionalized graphene;

(2) in a nitrogen atmosphere, adding amino functionalized graphene into a toluene solvent, uniformly dispersing by ultrasonic, dropwise adding pyridine and 2-bromoisobutyryl bromide, stirring and reacting for 1-3h in an ice water bath, heating to 20-30 ℃, reacting for 10-20h, performing centrifugal separation, washing and drying to prepare bromoamide functionalized graphene;

(3) adding bromoamide functionalized graphene into a distilled water solvent in a nitrogen atmosphere, uniformly dispersing by ultrasonic, and then adding styrene, an activator pentamethyldiethylenetriamine, a catalyst CuBr and a cocatalyst CuBr₂Freezing at-30 ℃ to-10 ℃, then unfreezing at 20-40 ℃ in a vacuum drying oven, repeating the freezing-unfreezing process for 2-4 times, heating to 50-70 ℃ in a nitrogen atmosphere, stirring for 2-6h, centrifugally washing and drying, mixing the solid product through a two-roll plasticator mill, extruding through a single-screw extruder, and preparing the high-strength graphene toughening modified polystyrene material.

2. The high-strength graphene toughened and modified polystyrene material as claimed in claim 1, wherein: the mass ratio of the hydroxylated graphene, the triethanolamine and the 3-aminopropyltriethoxysilane in the step (1) is 100:1-3: 20-50.

3. The high-strength graphene toughened and modified polystyrene material as claimed in claim 1, wherein: the ultrasonic treatment instrument in the step (1) comprises an ultrasonic device, an ultrasonic probe is arranged below the ultrasonic device, a gear rod is fixedly connected to the inner wall of the ultrasonic treatment instrument, a rotating gear is movably connected to the gear rod, a moving rod is movably connected to the rotating gear, a clamp plate is fixedly connected to the moving rod, and a reaction bottle is movably connected to the clamp plate.

4. The high-strength graphene toughened and modified polystyrene material as claimed in claim 1, wherein: the mass ratio of the amino functionalized graphene, the pyridine and the 2-bromine isobutyryl bromide in the step (2) is 100:600-1200: 40-80.

5. The high-strength graphene toughened and modified polystyrene material as claimed in claim 1, wherein: in the step (3), bromoamide functionalized graphene, styrene, pentamethyldiethylenetriamine, CuBr and CuBr₂The mass ratio of (A) to (B) is 0.2-1:100:4-6:0.6-1: 10-20.

Technical Field

The invention relates to the field of polystyrene materials, in particular to a high-strength graphene toughening modified polystyrene material and a preparation method thereof.

Background

Single electron transfer living radical polymerization (SET-LRP) is a novel high-efficiency organic polymer synthesis method, and has the advantages of wide monomer application range, mild reaction conditions, high reaction rate, easiness in separation and the like, so that the single electron transfer living radical polymerization has wider research prospect and application value compared with other living radical polymerization.

The high impact polystyrene is an engineering plastic which is easy to process, strong in corrosion resistance and good in impact resistance, and other engineering plastics, the high impact polystyrene is low in price, can be widely used in the light industry market, decoration, illumination indication, packaging materials and other aspects, can be used as an insulating material and a heat insulation material in the electrical aspect, can be used for manufacturing materials such as instrument shells, optical chemical instrument parts, transparent films, capacitor dielectric layers and the like, and has important application.

In order to further improve the comprehensive mechanical properties of polystyrene, an inorganic nano material can be compounded with polystyrene to form an organic-inorganic hybrid material, so that the properties of polystyrene are improved, graphene nanoparticles have excellent mechanical properties, thermal properties and electrical properties, and have a large specific surface area, and can be used as a suitable filler of polymer nanocomposites such as polystyrene and epoxy resin, but strong van der waals force exists among the graphene nanoparticles, so that stacking and agglomeration can occur in polymer groups, and the problem that the properties of the polymer materials are affected due to poor dispersibility is caused, so that the improvement of the dispersibility and compatibility of graphene in polymer matrixes such as polystyrene becomes a significant challenge and research hotspot.

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides a high-strength graphene toughening modified polystyrene material and a preparation method thereof, solves the problem of low mechanical properties such as tensile strength of polystyrene, and solves the problem of non-uniform dispersion of graphene in polystyrene.

(II) technical scheme

In order to achieve the purpose, the invention provides the following technical scheme: a preparation method of a high-strength graphene toughening modified polystyrene material comprises the following steps:

(1) adding ethanol solvent and hydroxylated graphene into a reaction bottle, placing the reaction bottle in an ultrasonic treatment instrument for ultrasonic dispersion, adding triethanolamine and 3-aminopropyltriethoxysilane, heating to 40-80 ℃, stirring at a constant speed for reaction for 6-12h, filtering the solvent, washing with ethanol, and drying to obtain the amino functionalized graphene.

(2) Adding a toluene solvent and amino functionalized graphene into a reaction bottle in a nitrogen atmosphere, after uniform ultrasonic dispersion, slowly dropwise adding pyridine and 2-bromoisobutyryl bromide, reacting for 1-3h in an ice-water bath with uniform stirring, then heating to 20-30 ℃, reacting for 10-20h with uniform stirring, centrifugally separating the solution by using the toluene solvent, washing and drying to prepare bromoamide functionalized graphene.

(3) Adding distilled water and bromoamide functionalized graphene into a reaction bottle in a nitrogen atmosphere, adding styrene and pentamethyldiethylenetriamine after uniform ultrasonic dispersion, adding CuBr and CuBr after uniform stirring₂Freezing at-30 ℃ to-10 ℃, then unfreezing at 20-40 ℃ in a vacuum drying oven, repeating the freezing-unfreezing process for 2-4 times, heating to 50-70 ℃ in a nitrogen atmosphere, stirring at a constant speed for reaction for 2-6h, centrifugally washing and drying the solution by using distilled water, mixing and milling solid products by a double-roll plasticator, and extruding by a single-screw extruder to obtain the high-strength graphene toughening modified polystyrene material.

Preferably, the mass ratio of the hydroxylated graphene, the triethanolamine and the 3-aminopropyltriethoxysilane in the step (1) is 100:1-3: 20-50.

Preferably, the ultrasonic treatment instrument in the step (1) comprises an ultrasonic device, an ultrasonic probe is arranged below the ultrasonic device, a gear rod is fixedly connected to the inner wall of the ultrasonic treatment instrument, the gear rod is movably connected with a rotating gear, the rotating gear is movably connected with a moving rod, a clamp plate is fixedly connected with the moving rod, and a reaction bottle is movably connected with the clamp plate.

Preferably, the mass ratio of the amino functionalized graphene, the pyridine and the 2-bromoisobutyryl bromide in the step (2) is 100:600-1200: 40-80.

Preferably, the bromoamide functionalized graphene, styrene, pentamethyldiethylenetriamine, CuBr and CuBr in the step (3)₂The mass ratio of (A) to (B) is 0.2-1:100:4-6:0.6-1: 10-20.

(III) advantageous technical effects

Compared with the prior art, the invention has the following experimental principles and beneficial technical effects:

according to the high-strength graphene toughening modified polystyrene material, a large number of hydroxyl groups of hydroxylated graphene can promote reaction with 3-aminopropyltriethoxysilane to obtain amino functionalized graphene with high grafting rate, abundant amino groups and acyl bromide groups of 2-bromoisobutyryl bromide carry out substitution reaction to obtain bromoamide functionalized graphene, the bromoamide functionalized graphene is used as a macromolecular initiator, bromine atoms in bromoamide groups are used as single electron transfer active sites, styrene is efficiently initiated to carry out in-situ polymerization on the surface of the graphene through single electron transfer active free radical polymerization to obtain graphene chemical covalent grafting polystyrene, the graphene is uniformly dispersed in a matrix of the polystyrene through chemical bond modification, the bond energy of the chemical bond is far stronger than the van der Waals force among graphene nanoparticles, so that the interface compatibility of the graphene and the polystyrene is improved, the phenomena of aggregation and aggregation of graphene nanoparticles are avoided, the mechanical properties such as tensile strength, impact strength and the like of polystyrene are remarkably improved by uniformly dispersed graphene, and a brand-new and efficient synthesis method is provided for synthesizing polystyrene and polystyrene grafted graphene by virtue of abundant single electron transfer active free radical polymerization.

Drawings

FIG. 1 is a schematic front view of an ultrasonic treatment apparatus;

FIG. 2 is an enlarged schematic view of the travel bar;

fig. 3 is a schematic view of splint adjustment.

1-ultrasonic treatment instrument; 2-an ultrasonic device; 3-an ultrasonic probe; 4-a gear lever; 5-a rotating gear; 6-moving the rod; 7-clamping plate; 8-reaction flask.

Detailed Description

To achieve the above object, the present invention provides the following embodiments and examples: a preparation method of a high-strength graphene toughened and modified polystyrene material comprises the following steps:

(1) adding ethanol solvent and hydroxylated graphene into a reaction bottle, placing the reaction bottle in an ultrasonic treatment instrument for ultrasonic dispersion, adding triethanolamine and 3-aminopropyltriethoxysilane at a mass ratio of 100:1-3:20-50, heating to 40-80 ℃, stirring at a constant speed for reaction for 6-12h, filtering the solvent, washing with ethanol, and drying to obtain the amino functionalized graphene.

(2) Adding a toluene solvent and amino functionalized graphene into a reaction bottle in a nitrogen atmosphere, slowly adding pyridine and 2-bromoisobutyryl bromide dropwise after uniform ultrasonic dispersion, wherein the mass ratio of the pyridine to the 2-bromoisobutyryl bromide is 100:600-1200:40-80, reacting for 1-3h in an ice water bath with uniform stirring, heating to 20-30 ℃, reacting for 10-20h with uniform stirring, centrifugally separating the solution by using the toluene solvent, washing and drying to prepare the bromoamide functionalized graphene.

(3) Adding distilled water and bromoamide functionalized graphene into a reaction bottle in a nitrogen atmosphere, adding styrene and an activator pentamethyldiethylenetriamine after uniform ultrasonic dispersion, adding a catalyst CuBr and a cocatalyst CuBr after uniform stirring₂The mass ratio of the five components is 0.2-1:100:4-6:0.6-1:10-20, freezing treatment is carried out at the temperature of minus 30 ℃ to minus 10 ℃, then the frozen product is placed in a vacuum drying oven to be unfrozen at the temperature of 20 ℃ to 40 ℃, the freezing-unfreezing process is repeated for 2 times to 4 times, the frozen product is heated to the temperature of 50 ℃ to 70 ℃ in the nitrogen atmosphere, the mixed product is stirred at a constant speed for reaction for 2 hours to 6 hours, the solution is centrifugally washed and dried by using distilled water, the solid product is mixed and refined by a double-roll plasticator, and then the mixture is extruded by a single-screw extruder to prepare the high-strength graphene toughening modified polystyrene material.