CN110229400B

CN110229400B - PE nano composite material and preparation method thereof

Info

Publication number: CN110229400B
Application number: CN201810183616.5A
Authority: CN
Inventors: 马永梅; 郑鲲; 张京楠; 曹新宇; 叶钢; 尚欣欣
Original assignee: Institute of Chemistry CAS
Current assignee: Institute of Chemistry CAS
Priority date: 2018-03-06
Filing date: 2018-03-06
Publication date: 2021-04-30
Anticipated expiration: 2038-03-06
Also published as: CN110229400A

Abstract

A PE nano composite material is prepared by melt blending of mixed materials; the blend includes PE with nanomaterial and liquid medium bonded to PE particles. The invention also discloses a preparation method of the PE nano composite material, which comprises the following specific steps of A, mixing and stirring the nano material and the liquid medium to form a pasty nano material mixture; B. mixing and stirring the nano material mixture in the step A and PE particles to form a blend; C. and C, melting and blending the blend obtained in the step B to obtain the PE nano composite material. The tensile strength and the impact strength of the nano composite material are improved on the basis of the PE base material, and the nano composite material is simple in preparation method, low in production cost and easy to popularize.

Description

PE nano composite material and preparation method thereof

Technical Field

The invention belongs to the field of nano composite materials and preparation thereof, and particularly relates to a PE nano composite material and a preparation method thereof.

Background

Polyethylene (PE) has excellent physical and mechanical properties, electrical insulation properties, and flexible and versatile processing properties, and its overall properties are incomparable with most other thermoplastic resins, and is one of the most widely used thermoplastics. Although polyethylene has been widely used in engineering, its inherent drawbacks and deficiencies limit its further applications. At this time, the special properties exhibited by the nanocomposite material, which are different from those of the general composite material, indicate a new way for the modification research of polyethylene. A large number of researches prove that the composite material of the polyethylene and the layered nanometer material can obviously improve the comprehensive performance of the nanometer composite material. The present preparation method of polyethylene nano composite material mainly adopts in-situ intercalation and melting intercalation method. Because the in-situ intercalation industrial investment is large, the period is long, and the large-scale popularization and application are difficult; the melting intercalation can be carried out in common plastic mixing equipment, the processing is convenient, however, the lamellar nano-material needs to be organized and intercalated in the early stage, and the completely stripped polyethylene nano-composite material is not easy to obtain. With the development of science and technology, engineering application puts higher requirements on the properties of the polyethylene material in impact strength, bending strength and tensile strength.

Patent No. CN101081928A proposes a method for preparing a nano composite material, which adopts a water-assisted method to prepare a polyamide/nano montmorillonite master batch, and the preparation method comprises the steps of using deionized water as an intercalation agent, mixing purified montmorillonite and deionized water, fully dispersing to prepare montmorillonite slurry, gradually adding the montmorillonite slurry into polyamide with completely melted components, and then extruding and granulating to obtain the polyamide/nano montmorillonite master batch. The preparation method is simple and low in production cost, but the montmorillonite slurry is added after the polyamide is melted, so that the montmorillonite slurry is not ready to be completely mixed with the copolymer, water between layers is gasified at high temperature, and the montmorillonite cannot be well dispersed into the polyamide, so that the product performance is improved to a limited extent; in addition, the montmorillonite slurry can be injected into the double screws only by increasing a certain pressure in the charging mode, and meanwhile, because the processing section of the double screws is short, the feeding interval of the montmorillonite slurry is increased midway, the length of the double screws needs to be increased, so that the process is more complicated and the cost is higher.

The present invention has been made in view of this situation.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a PE nano composite material which simultaneously improves the tensile strength and the impact strength, has a simple preparation method and low production cost and is easy to popularize and a preparation method thereof.

In order to solve the technical problems, the invention provides a PE nano composite material, which is prepared by melting and blending mixed materials; the blend includes PE with nanomaterial and liquid medium bonded to PE particles.

In the scheme, the PE nano composite material is prepared by feeding PE particles, the nano material and a liquid medium together. The PE particles are connected with each other through the nanometer material and the liquid medium to form a non-layered blend. The method well solves the problem that in the traditional method, PE and the nano material are blended, and the nano material slips and cannot be fed together.

Further, the nano material comprises one or more of a sheet nano material, a fibrous nano material and a granular nano material, and preferably one or more of nano silicon oxide, nano zinc oxide, carbon nano fiber, nano tungsten oxide and nano silicon.

The nano material in the scheme is a non-layered nano material, wherein the non-layered nano material comprises a flaky nano material, a granular nano material and a fiber nano material; specifically, the non-layered nanomaterial comprises: one or more of nano silicon oxide, nano titanium oxide, nano zirconium oxide, nano zinc oxide, nano aluminum oxide, nano nickel oxide, nano gold, nano silver, nano silicon, nano carbon, carbon nanofiber, carbon nanotube, nano graphite, nano boron powder, nano sulfur, nano lanthanum oxide, nano neodymium oxide, nano erbium oxide, nano cerium oxide, nano praseodymium oxide, nano yttrium oxide, nano europium oxide, nano tungsten oxide, nano silicon carbide, nano tellurium oxide, nano niobium oxide, nano hafnium oxide and nano molybdenum oxide. Preferably nano silicon oxide, nano zinc oxide, carbon nano fiber, nano tungsten oxide and nano silicon.

In a further scheme, the layered nano material can also be used in the invention, because the layered nano material has a unique two-dimensional plate layer structure, and the two-dimensional plate layers are directionally and orderly arranged to form a unique three-dimensional crystal structure, a liquid medium can be inserted into gaps between layers to prop the plate layers open under a certain condition without damaging the original structure of the layered nano material, and the plate layer composition and the layer spacing of the layered nano material are adjustable and controllable. When the liquid medium enters the interlayer and the interlayer spacing is expanded due to the liquid medium, when the temperature is raised to or above the plasticizing temperature of the PE, the liquid medium entering the interlayer of the layered nano material is further gasified and exploded, the generated huge energy peels off the lamellar layer of the layered material, and the peeled lamellar layer is orderly dispersed into the molten PE under continuous stirring. The layered nano material comprises one or more of montmorillonite, layered silicate, kaolin, graphene, hydrotalcite and black phosphorus.

Further, the liquid medium is dispersed among the nano materials to form a paste with certain self-adhesiveness, and the consistency of the paste is 0-100mm but not 0;

preferably, the mass part ratio of the liquid medium to the nano material is 3-100: 1; preferably 5-50: 1; more preferably 5 to 20: 1.

Compared with the process of modifying, filtering and drying the nano material by interlayer polymerization in the prior art, the process has the advantages that the continuous and self-adhesive paste is formed after the liquid medium is injected between the layers of the layered nano material, the paste has certain consistency but the consistency is not 0mm, and the paste represents that the paste is combined with the liquid medium, so that the nano material paste combined with the liquid medium can be uniformly adhered to the surface of PE (polyethylene) particles and is fed to a melting and blending device together with the PE particles, and the processability is improved.

Further, the paste also contains an auxiliary agent, wherein the auxiliary agent is one or more of a carboxylate surfactant, a sulfate surfactant, a sulfonate surfactant, a phosphate surfactant, an amine salt surfactant, a quaternary ammonium salt surfactant, a heterocyclic surfactant, a nonionic surfactant, a natural water-soluble polymer, a synthetic water-soluble polymer and a prepolymer thereof; wherein, one or more of synthetic water-soluble macromolecule and prepolymer thereof are preferred;

preferably, the mass part ratio of the auxiliary agent to the nano material is 0.01-50: 1; preferably 0.1 to 5: 1; more preferably 0.2 to 1: 1.

In the scheme, the addition of the auxiliary agent can improve the capability of a liquid medium entering the nano material, so that the consistency of the nano material mixture is increased; in addition, the addition of the auxiliary agent can also increase the boiling point of the liquid medium and prevent the liquid medium from gasifying and escaping in advance. The reaction temperature for generating the paste-like nano material in the invention can be at room temperature, and the requirement on the auxiliary agent is not high, so that the auxiliary agent applicable to the invention has wider alternative range. The auxiliary agent comprises one or more of water-soluble polymer and prepolymer thereof, preferably polyaspartic acid, lecithin, sodium alginate, polyacrylic acid, polyvinylamine and hyaluronic acid;

wherein the surfactant comprises:

1. anionic surfactant: classified into carboxylates, sulfate ester salts, sulfonates, and phosphate ester salts.

(1) The soap is higher fatty acid salt, and the molecular structure general formula is (RCOO) -nMn +. Stearic acid, oleic acid, lauric acid and the like are commonly used. Depending on the metal ion (Mn +) thereof, there are alkali metal soaps, alkaline earth metal soaps, organic amine soaps and the like.

(2) The sulfated product is mainly sulfated oil and sulfate of higher fatty alcohol, and has molecular structure formula of ROSO3-M +, and commonly used sodium dodecyl sulfate (also known as "sodium lauryl sulfate"), sodium hexadecyl sulfate (also known as "sodium cetyl sulfate"), and sodium octadecyl sulfate (also known as "sodium stearyl sulfate").

(3) The sulfonic acid compound is mainly aliphatic sulfonic acid compound, sulfoaryl sulfonic acid compound, sulfonaphthalene sulfonic acid compound, etc

2. Cationic surfactant: the hydrophilic group ion of the cationic surfactant contains a nitrogen atom, and is classified into amine salts and heterocyclic types according to the position of the nitrogen atom in the molecule.

3. Zwitterionic surfactant: lecithin, amino acid type, betaine type

4. Nonionic surfactant: fatty glyceride, sorbitan fatty acid, polysorbate, alkylphenol polyoxyethylene, fatty alcohol polyoxyethylene, fatty acid methyl ester polyoxyethylene, and detergent.

The water-soluble polymer comprises

1. Natural polymer

Starches;

marine algae species: sodium alginate and agar;

vegetable gums: gum arabic, gum tragacanth, locust bean gum, tamarind seed polysaccharide gum, sesbania gum, carrageenan, guar gum, pectin;

animal glue: gelatin, casein, chitosan;

microbial glue: xanthan gum, gellan gum, hyaluronic acid.

2. Synthetic organic polymer

(1) Water-soluble polymer of polymerization type

Polyacrylamide, polyacrylic acid, polymethacrylic acid and copolymers thereof, polyvinyl alcohol, polyethylene glycol, polyethylene oxide, polyvinylpyrrolidone, polymaleic anhydride, polydimethyldiallyl ammonium chloride, polyvinylamine, polydivinyl imidazoline, sodium polystyrene sulfonate, sulfonated styrene maleic anhydride copolymer and Kelvin resin;

(2) condensed water-soluble polymer

Water-soluble amino resin, water-soluble phenolic resin, water-soluble alkyd resin, water-soluble epoxy resin, water-soluble polyurethane resin, polyethyleneimine, polyaspartic acid, polyepoxysuccinic acid, polyamide epichlorohydrin resin, polyamide glyoxal resin, ammonia-epichlorohydrin resin, heavy polyamine epichlorohydrin resin, ammonia-dimethylamine-epichlorohydrin resin, N-dimethyl-1, 3-propanediamine and epichlorohydrin resin;

(3) others

Water-soluble maleic anhydride oil, dicyandiamide-formaldehyde resin, rosin amine-ethylene oxide polycondensate, poly N-vinyl acetamide and water-soluble polysucrose.

3. Semi-synthetic polymer

Modified cellulose and modified starch;

further, the boiling point of the liquid medium is below the plasticization temperature of the PE, preferably below 180 ℃, more preferably water.

In the above embodiment, the boiling point of the liquid medium is lower than the plasticizing temperature of PE, and preferably the boiling point of the liquid medium is lower than 180 ℃. The liquid medium is selected from: isopentane, n-pentane, petroleum ether, hexane, cyclohexane, isooctane, trifluoroacetic acid, trimethylpentane, cyclopentane, heptane, butyl chloride, trichloroethylene, carbon tetrachloride, trichlorotrifluoroethane, propyl ether, toluene, p-xylene, chlorobenzene, o-dichlorobenzene, diethyl ether, benzene, isobutanol, ethylene dichloride, n-butanol, butyl acetate, propanol, methyl isobutyl ketone, tetrahydrofuran, ethyl acetate, isopropanol, chloroform, methyl ethyl ketone, dioxane, pyridine, acetone, nitromethane, acetonitrile, dimethylformamide, methanol, water, methylamine, dimethylamine, diethyl ether, pentane, dichloromethane, carbon disulfide, 1, 1-dichloroethane, trifluoroacetic acid, 1, 1, 1-trichloroethane, ethanol, butanone, 1, 2-dichloroethane, ethylene glycol dimethyl ether, triethylamine, propionitrile, 4-methyl-2-pentanone, methyl alcohol, ethyl acetate, isopropyl alcohol, ethyl acetate, methyl ether, ethyl acetate, methyl ethyl ketone, ethyl acetate, dimethyl ether, dimethyl formamide, dimethyl, One or more of ethylenediamine, butanol, acetic acid, ethylene glycol monomethyl ether, octane, morpholine ethylene glycol monoethyl ether, xylene, m-xylene, acetic anhydride, o-xylene, N-dimethylformamide, cyclohexanone, cyclohexanol, furfural, N-methylformamide, and the like. Preferably, o-dichlorobenzene, water, trimethylpentane, isopentane, acetic acid, toluene; water is more preferable in view of manufacturing cost and pollution problem to the environment.

Further, the mass part ratio of the nano material to the PE in the mixed material is 0.1-20: 100; preferably 1-10: 100, respectively; more preferably 3 to 5: 100.

Preferably, the mixture also comprises an anti-aging agent, and the mass part ratio of the anti-aging agent to the PE is 0.1-1: 100; preferably 0.2-0.8: 100; more preferably 0.3 to 0.6: 100.

In the scheme, an anti-aging agent can be added in the step B to reduce the influence of the liquid medium on the performance of the nano composite material, wherein the mass part ratio of the anti-aging agent to the PE is 0.1-1: 100; preferably 0.2-0.4: 100; more preferably 0.3 to 0.4: 100.

The anti-aging agent is selected from amine antioxidants, ketone amine condensate, diaryl secondary amine, substituted p-phenylenediamine and hindered amine;

phenolic antioxidants, which can be classified as alkylated monophenols, alkylated polyphenols, thiobisphenols and polyphenols. The main classes of alkylated monophenol and polyphenol antioxidants are antioxidants 264, 1076, 2246, 1035, 1010, 3114 and 1790. The main varieties of thiobisphenols are anti-aging agents 2246 and 300. The main varieties of the polyphenol antioxidant comprise 2, 5-di-tert-butyl hydrogen and 2, 5-di-tert-amyl hydroquinone;

antioxidant of thio dipropyl acetic acid and phosphorous acid vinegar, which is mainly composed of antioxidant TNP, Ultranox624 and tris (2, soul-di-tert-T phenyl) phosphite;

other types of antioxidants, 2-sulfobenzimide under the trade name antioxidant MB, nickel dibutyldithiocarbamate under the trade name antioxidant NBC, and also zinc dialkyldithiophosphate;

the main antioxidants are: one or more of antioxidant RD, antioxidant AW, antioxidant BLE, antioxidant A, antioxidant OD, 4 '-bis (alpha-methylbenzyl) diphenylamine, 4' -bis (alpha, alpha-methylbenzyl) diphenylamine, N, -di-sec-butyl p-phenylenediamine, antioxidant 4030, antioxidant 4010NA, antioxidant 4020, antioxidant 264, antioxidant 1076, antioxidant 2216, antioxidant 1035, antioxidant 1010, antioxidant 3114, antioxidant 1790, antioxidant 2246, 2, 5-di-tert-butylhydroquinone, antioxidant DLTP, antioxidant TNP, Ultranox624, tris (2, 4-di-tert-T-butylphenyl) phosphite, antioxidant MB, antioxidant NBC and zinc dialkyldithiophosphate; preferably, antioxidant RD, antioxidant AW, antioxidant 4010NA, antioxidant 3114 and antioxidant 264.

Further, the preparation method is characterized by comprising the following steps:

A. mixing and stirring the nano material and a liquid medium to form a pasty nano material mixture;

B. mixing and stirring the nano material mixture in the step A and PE particles to form a blend;

C. and C, melting and blending the blend obtained in the step B to obtain the PE nano composite material.

According to the scheme, the liquid medium enters the nano material, the pasty nano material with certain self-adhesiveness is prepared under the condition of full stirring, the pasty nano material and the PE are mixed and stirred uniformly, and the mixture can be directly added into a feeding area without applying pressure or feeding midway, so that the process is saved, and the cost is reduced. In addition, the nanometer material and PE are mixed and then added, and then the mixture is melted and blended, the melted PE can cover the nanometer material to form a protective layer, when a liquid medium entering the nanometer material is gasified, and the vapor pressure in the nanometer material is greater than the melt pressure of the PE, huge internal violence can be generated to separate the nanometer material, and the separated nanometer material is uniformly dispersed into the PE.

In the above scheme, latex may be further added to coat the pasty nanomaterial mixture obtained in step a, the latex including: the emulsion comprises one or more of styrene-acrylic emulsion, acrylate emulsion, acrylic emulsion, silicone-acrylic emulsion, aqueous polyurethane emulsion, fluorocarbon emulsion, rosin resin emulsion, terpineol, vinyl acetate-acrylic emulsion, aqueous epoxy resin emulsion, styrene-butadiene latex, natural latex, white latex, neoprene latex, pure acrylic latex, carboxylic styrene-butadiene latex and styrene-acrylic latex, and one or more of styrene-acrylic emulsion, silicone-acrylic emulsion, vinyl acetate-acrylic emulsion and styrene-acrylic latex is preferred.

In the scheme, the latex is added to coat the nano material mixture to form a protective layer, when the nano material mixture and the PE are melted and blended, the liquid medium entering the nano material is gasified, when the vapor pressure in the protective layer is greater than the melt pressure of the PE, the internal explosion force is generated to separate the agglomerated nano material, and the separated nano material can be highly dispersed in the melted PE through continuous stirring and/or shearing.

In the above scheme, the melt extrusion process in step C may be banburying, roll mixing, screw (parallel/conical/single/double/triple screw).

In the scheme, when the double-screw extruder is adopted, the problems that the nano material and PE are slipped and cannot be fed simultaneously are well solved, the PE and the nano material are mixed and fed in the presence of a liquid medium, pressure is not required to be applied during feeding, and in addition, the nano material can be dispersed in PE seeds more fully through the shearing force of the double-screw extruder and the internal explosion force of liquid medium gasification in the melting process of the PE and the nano material.

Wherein the rotating speed of a main machine of the double-screw extruder is 30-80Hz, the rotating speed of a main feeding hopper is 10-30Hz, the extrusion temperature is 150-; preferably, the rotation speed of the host is 60-80Hz, the rotation speed of the main feeding hopper is 20-30Hz, the extrusion temperature is 150-180 ℃ in the first zone, 245-260 ℃ in the second zone, 245-260 ℃ in the third zone, 245-260 ℃ in the fourth zone and 245-260 ℃ in the fifth zone.

Further, an auxiliary agent is added in the step A, and the auxiliary agent can be added at one time or added in batches;

preferably, physical means can be added in the step A to promote the dispersion of the liquid medium among the nano materials, and the physical means comprises colloid milling, ball milling, ultrasound, vortex, etching assistance and airflow impact.

In the scheme, the addition of the auxiliary agent can improve the capability of a liquid medium entering the nano material, so that the consistency of the nano material mixture is increased; in addition, the addition of the auxiliary agent can also increase the boiling point of the liquid medium and prevent the liquid medium from gasifying and escaping in advance.

In the scheme, the dispersion of the liquid medium in the nano material can be promoted by means of a physical mode, wherein the physical mode comprises but is not limited to ultrasonic mode, colloid mill mode, ball milling mode, vortex mode, etching auxiliary mode, airflow impact mode and the like, the ultrasonic frequency is 800-1000 Hz, and the power is 200-1000W.

Further, in the step (3), the method comprises the following steps: (1) heating, and mixing and contacting the PE with the liquid medium and the nano material in the paste under first stirring, softening, mutually permeating and coating; (2) and after the temperature is higher than the boiling point of the liquid medium, partially gasifying the liquid medium, and carrying out secondary stirring on the mixed material by gasifying.

Preferably, in the step C, the mixture is melted and blended, and the liquid in the paste is at the temperature higher than or equal to the plasticizing temperature of PE during the melting and blending process

Further gasifying the bulk medium to separate the agglomerated nanometer materials;

further preferably, in the step C, when the mixed materials are melted and blended, the liquid medium is gasified to promote the fluidity of the mixed materials and promote the heat conduction, the liquid medium is gasified to soften the hot PE, and the plasticizing temperature of the hot PE is reduced

In the scheme, the PE, the liquid medium and the nano material are further contacted and mixed through continuous stirring, the PE starts to soften along with the rise of the temperature, and the softened PE coats the nano material, so that the blend coated by the PE and the nano material in an interpenetration manner is formed. With the further increase of the temperature, when the temperature is higher than the boiling point of the liquid medium, the liquid medium is partially gasified, so that the bubbling phenomenon can occur in the blend, and further stirring of the blend is realized.

In the above scheme, when the temperature rises to or above the plasticizing temperature of PE, the liquid medium entering the nanomaterial is further gasified, the gasification generates huge energy and separates the agglomerated nanomaterial, and the separated nanomaterial is uniformly dispersed into the molten PE under continuous stirring.

In the scheme, when the PE and the nanometer materials are melted and blended, the liquid medium entering between the nanometer materials is gasified, the heat in the blend can be continuously transferred under the gasification, so that the blend is uniformly heated, and in addition, the PE is further softened due to the gasification of the liquid medium, so that the PE and the nanometer materials are more fully permeated and coated. In addition, the plasticizing temperature is also reduced due to the existence of water vapor.

The invention also provides a mixed material, which comprises: paste and PE;

the paste comprises: 1 part of nano material, 5-100 parts of liquid medium and 0-50 parts of auxiliary agent by weight but not 0; the paste is adhered to the surface of the PE particles to form a mixed material;

preferably, the nanomaterial and the adjuvant are added to the liquid medium and dispersed in sequence during the preparation of the paste.

In the above-mentioned scheme, a self-adhesive paste is prepared by mixing the nano material, the liquid medium and a proper amount of the auxiliary agent, when the PE base material is mixed with the paste, the paste is adhered to the PE particles, and the PE particles are adhered to each other through the paste. The nano material, the liquid medium and the PE particles well solve the problem that the raw materials cannot be fed together due to slipping in the prior art.

After adopting the technical scheme, compared with the prior art, the invention has the following beneficial effects:

1. the process is simple, the nano material and the liquid medium are mixed to form paste, and the paste and the PE are melted and blended together to obtain the nano composite material, and the nano material does not need to be subjected to complex organic treatment;

2. in the feeding mode, the invention realizes the simultaneous feeding of the nano material and the PE in the presence of the liquid medium, saves the problem that the screw length needs to be increased during the feeding of the nano material, has lower production cost and easy popularization, and can reduce the environmental pollution particularly by taking water as the liquid medium.

3. The nanometer material and PE are melted and mixed together, so that the nanometer material can be better dispersed into the PE, and the impact strength and the tensile strength of the nanometer composite material prepared by the method are simultaneously improved.

Detailed Description

Example 1

PE/nano silicon oxide nano composite material

Raw materials: PE 100 parts water 40 parts nano silica 10 parts open-air adhesive 1 part

The preparation method comprises the following steps:

1. stirring the water in parts by weight under the ultrasonic condition of 1000HZ and 200W, slowly adding the nano silicon oxide powder, carrying out ultrasonic treatment for 30min, then adding gelatin, and continuing the ultrasonic treatment for 60min to finally form a pasty nano silicon oxide mixed material, wherein the consistency of the mixed material is 40 mm;

2. PE and the pasty nano silicon oxide mixed material are mixed and stirred evenly and are put into a feed inlet of a double-screw extruder;

3. and further melting and mixing the PE and the nano-silicon oxide, and performing extrusion granulation and drying to obtain the PE nano-silicon oxide nano-composite material.

The rotating speed of a main machine of the extrusion equipment is 30Hz, the rotating speed of a main feeding hopper is 10Hz, the extrusion temperature is 160 ℃ in a first area, 190 ℃ in a second area, 190 ℃ in a third area, 200 ℃ in a fourth area, 200 ℃ in a fifth area, and the linear speed of the rotating speed of the screw is 0.8 m/s.

Example 2

PE/nano titanium oxide nano composite material

Raw materials: 100 portions of PE, 100 portions of water, 20 portions of nano titanium oxide, 0.2 portion of water-soluble epoxy resin, 0.2 portion of antioxidant RD

1. Stirring the water in parts by weight under the ultrasonic condition of 1000HZ and 1000W, slowly adding the nano titanium oxide powder, performing ultrasonic treatment for 30min, then adding the water-soluble epoxy resin, and continuing performing ultrasonic treatment for 60min to obtain a pasty nano titanium oxide mixed material, wherein the consistency of the mixed material is 63 mm;

2. PE and the pasty nano titanium oxide mixed material are mixed and stirred evenly and are put into a feed inlet of a double-screw extruder;

3. and further melting and mixing the PE and the nano titanium oxide, and performing extrusion granulation and drying to obtain the PE/nano titanium oxide nano composite material.

The rotating speed of a main machine of the extrusion equipment is 80Hz, the rotating speed of a main feeding hopper is 30Hz, the extrusion temperature in a first zone is 180 ℃, a second zone is 195 ℃, a third zone is 195 ℃, a fourth zone is 195 ℃ and a fifth zone is 190 ℃; the linear speed of the screw speed was 1 m/s.

Example 3

PE/nano zinc oxide nano composite material

Raw materials: PE 100 parts of trimethylpentane 100 parts of nano zinc oxide 0.5 part of lecithin 2.5 parts of anti-aging agent AW 0.3 part

The preparation method comprises the following steps:

1. stirring trimethylpentane in parts by weight under the ultrasonic condition of 800HZ and 1000W, slowly adding nano zinc oxide powder into the trimethylpentane, adding lecithin after ultrasonic treatment for 30min, and continuing ultrasonic treatment for 60min to obtain a pasty nano zinc oxide mixed material, wherein the consistency of the mixed material is 90 mm;

2. mixing PE with the paste-like nano zinc oxide mixed material and the anti-aging agent RD, stirring uniformly, and adding into an internal mixer;

3. and further melting and blending the PE and the nano zinc oxide in an internal mixer at 300 ℃, carrying out internal mixing and compounding for 3 hours, and carrying out granulation and drying to obtain the PE/nano zinc oxide nano composite material.

Example 4

PE/carbon nanofiber nanocomposite

Raw materials: 100 parts of PE (polyethylene), 30 parts of water, 3 parts of carbon nanofiber, 12 parts of sodium alginate and 31140.4 parts of antioxidant

The preparation method comprises the following steps:

1. slowly stirring the water in parts by weight, adding kaolin powder, adding sodium alginate, and fully stirring to form a pasty carbon nanofiber mixed material, wherein the consistency of the mixed material is 77 mm;

2. mixing and uniformly stirring the PE, the carbon nanofiber mixed material and the antioxidant 3114, and adding the mixture into a feeding area of a double-screw extruder;

3. and further melting and mixing the PE and the carbon nanofibers, and performing extrusion granulation and drying to obtain the PE/carbon nanofiber nanocomposite material.

The rotating speed of a main machine of the extrusion equipment is 60Hz, the rotating speed of a main feeding hopper is 25Hz, the extrusion temperature in a first zone is 200 ℃, a second zone is 220 ℃, a third zone is 220 ℃, a fourth zone is 220 ℃ and a fifth zone is 215 ℃; the linear speed of the screw speed was 0.8 m/s.

Example 5

PE/nano tungsten oxide nano composite material

Raw materials: 100 portions of PE, 25 portions of toluene, 5 portions of nano tungsten oxide, 1 portion of polyacrylic acid and 22460.5 portions of anti-aging agent

1. Slowly stirring the toluene in parts by weight, adding the nano tungsten oxide powder, adding the polyacrylic acid, and fully stirring to form a pasty nano tungsten oxide mixed material, wherein the consistency of the mixed material is 16 mm;

2. mixing PE with the nano tungsten oxide mixed material and the antioxidant 2246, uniformly stirring, and adding into an internal mixer;

3. and further melting and blending the PE and the nano tungsten oxide in an internal mixer at 300 ℃, internally mixing and compounding for 3 hours, discharging, and then granulating and drying to obtain the PE/nano tungsten oxide nano composite material.

Example 6

PE/nano silicon composite material

Raw materials: 100 portions of PE, 20 portions of water, 0.1 portion of nano-silicon, 1 portion of polyvinylamine, 0.6 portion of anti-aging agent MB

The preparation method comprises the following steps:

1. stirring the water in parts by weight under the ultrasonic condition of 1000HZ and 500W, slowly adding the nano-silicon powder, performing ultrasonic treatment for 30min, then adding the polyvinylamine, and continuing the ultrasonic treatment for 60min to finally form a pasty nano-silicon mixed material, wherein the consistency of the mixed material is 51 mm;

2. mixing the PE, the nano-silicon mixed material and the anti-aging agent MB, uniformly stirring, and adding into a feed inlet of a double-screw extruder;

3. and further melting and blending the PE and the nano-silicon, and performing extrusion granulation and drying to obtain the PE/nano-silicon nano-composite material.

The rotating speed of a main machine of the extrusion equipment is 60Hz, the rotating speed of a main feeding hopper is 20Hz, the extrusion temperature in a first zone is 180 ℃, a second zone is 200 ℃, a third zone is 200 ℃, a fourth zone is 200 ℃ and a fifth zone is 200 ℃; the linear speed of the screw speed was 0.9 m/s.

Example 7

PE/nano sulfur nano composite material

Raw materials: PE 100 parts, acetic acid 16 parts, nano sulfur 2 parts, hyaluronic acid 0.6 parts, anti-aging agent 4010NA 0.7 parts

The preparation method comprises the following steps:

1. slowly stirring the acetic acid in parts by weight, adding the nano sulfur powder, adding the hyaluronic acid, and fully stirring to form a pasty nano sulfur nano mixed material, wherein the consistency of the mixed material is 38 mm;

2. mixing PE, a nano sulfur nano mixed material and an anti-aging agent 4010NA, uniformly stirring, and adding into a feed inlet of a double-screw extruder;

3. and further melting and blending the PE and the montmorillonite/sepiolite, extruding, granulating and drying to obtain the PE/nano sulfur nano composite material.

The rotating speed of a main machine of the extrusion equipment is 70Hz, the rotating speed of a main feeding hopper is 15Hz, the extrusion temperature in a first zone is 180 ℃, a second zone is 180 ℃, a third zone is 200 ℃, a fourth zone is 200 ℃ and a fifth zone is 200 ℃; the linear speed of the screw speed was 1 m/s.

Example 8

PE montmorillonite/nano silicon oxide/nano titanium oxide nano composite material

Raw materials: PE 100 parts of water and toluene 80 parts of nano silicon oxide/nano titanium oxide 8 parts of lecithin/sodium alginate 4 parts of anti-aging agent NBC 0.8 part

Wherein the mass ratio of the nano silicon oxide to the nano titanium oxide is 1:1, the mass ratio of the water to the toluene is 1:1, and the mass ratio of the lecithin to the sodium alginate is 1: 1.

The preparation method comprises the following steps:

1. stirring the water and the toluene in parts by weight under the ultrasonic condition of 800HZ and 500W, slowly adding nano silicon oxide and nano titanium oxide powder, carrying out ultrasonic treatment for 30min, then adding lecithin and sodium alginate, and carrying out ultrasonic treatment for 60min to finally form a pasty nano silicon oxide/nano titanium oxide mixed material, wherein the consistency of the mixed material is 16 mm;

2. mixing PE with a nano silicon oxide/nano titanium oxide mixed material and an anti-aging agent NBC, uniformly stirring, and adding into a feed inlet of a double-screw extruder;

3. and further melting and blending the PE and the nano silicon oxide/nano titanium oxide, and performing extrusion granulation and drying to obtain the PE/nano silicon oxide/nano titanium oxide nano composite material.

The rotating speed of a main machine of the extrusion equipment is 60Hz, the rotating speed of a main feeding hopper is 30Hz, the extrusion temperature in a first zone is 180 ℃, a second zone is 200 ℃, a third zone is 180 ℃, a fourth zone is 180 ℃, and a fifth zone is 180 ℃; the linear speed of the screw speed was 0.7 m/s.

Example 9

PE/nano zinc oxide/carbon nanofiber/nano sulfur nanocomposite

Raw materials: PE 100 parts of toluene/acetic acid 75 parts of nano zinc oxide/carbon nanofiber/nano sulfur 15 parts of hard dicyandiamide formaldehyde resin/polyvinyl amine 6 parts of antioxidant 1035/anti-aging agent NBC 1 part

Wherein the mass ratio of toluene to acetic acid is 1:1, the mass ratio of nano zinc oxide, carbon nano fibers and nano sulfur is 1:1:1, the mass ratio of dicyandiamide formaldehyde resin to polyvinyl amine is 1:1, and the mass ratio of antioxidant 1035 to antioxidant NBC is 1: 1.

The preparation method comprises the following steps:

1. stirring the toluene and the acetic acid in parts by weight under the ultrasonic condition of 800HZ and 800W, slowly adding the nano zinc oxide, the carbon nano fibers and the nano sulfur powder, performing ultrasonic treatment for 30min, then adding dicyandiamide formaldehyde resin and polyethylene amine, and continuing performing ultrasonic treatment for 60min to finally form a pasty nano zinc oxide/carbon nano fibers/nano sulfur mixed material, wherein the consistency of the mixed material is 78 mm;

2. mixing PE with a nano zinc oxide/carbon nanofiber/nano sulfur mixed material, an antioxidant 1035 and an antioxidant NBC, uniformly stirring, and adding into a feed inlet of a double-screw extruder;

3. and further melting and blending the PE and the nano zinc oxide/carbon nano fiber/nano sulfur, and performing extrusion granulation and drying to obtain the PE/nano zinc oxide/carbon nano fiber/nano sulfur nano composite material.

The rotating speed of a main machine of the extrusion equipment is 30Hz, the rotating speed of a main feeding hopper is 30Hz, the extrusion temperature in a first zone is 190 ℃, a second zone is 220 ℃, a third zone is 200 ℃, a fourth zone is 200 ℃ and a fifth zone is 205 ℃; the linear speed of the screw speed was 1 m/s.

Comparative example 1

In the comparative example, on the basis of example 1, the position of adding the nano-silica into the extruder is adjusted, and the PE/nano-silica nanocomposite is prepared by adopting a water-assisted method.

Raw materials: PE 100 parts water 10 parts nano silicon oxide 0.1 part

The preparation method comprises the following steps:

1. mixing the water and the nano silicon oxide in parts by weight, and fully dispersing to prepare nano silicon oxide slurry;

2. putting PE into a feed inlet of a double-screw extruder, and melting the PE at high temperature;

3. and (3) putting the nano silicon oxide slurry into the completely molten PE, and performing extrusion granulation and drying to obtain the PE/nano silicon oxide nano composite material.

Wherein the process parameters of the twin-screw extruder are the same as in example 1.

Experimental example 1

In this example, the properties of the nanocomposites obtained in examples 1-10 were compared with those of the corresponding binders, as shown in Table 1.

Table 1:

categories	Tensile Strength (MPa)	Impact Strength (kg. cm/cm)
			Example 1	27	71
Example 2	25	65
			Example 3	26	69
Example 4	27	72
			Example 5	30	68
Example 6	28	70
			Example 7	26	69
Example 8	29	68
			Example 9	27	72
PE base material	23	58

From the above experimental results, it can be seen that the impact strength and tensile strength of examples 1-9 are greatly improved compared to the PE base material. The PE base material and the nano material are fed together in the presence of the liquid medium, the PE and the nano material are permeated and coated with each other in the PE melting process, and the nano material is separated and orderly dispersed in the melted PE by gasifying the liquid medium, so that the overall performance of the PE-nano composite material is improved.

Experimental example 2

This experimental example was used to compare the differences in nanomaterial content and performance between PE/nano silica nanocomposites prepared by different methods of example 1, comparative example 1, and comparative example 2 and PE monomer, as shown in table 2.

Table 2:

performance parameter	PE monomer	Example 1	Comparative example 1
				Content of the nano material%	0	2.0	1.6
Tensile strength MPa	23	28	27
				Bending strength MPa	15	19	18
Impact strength Kg cm/cm	58	67	45

From the above data, it can be seen that the nanomaterial content in the PE/nano silica nanocomposite prepared by the method of example 1 is higher than that in comparative example 1, indicating that nano silica can be sufficiently separated and well dispersed in PE by this method. In addition, the tensile strength, the bending strength and the impact strength of the product prepared in example 1 are all better than those of the PE monomer, while the impact strength of the product prepared in comparative example 1 is reduced though the tensile strength is improved, which further illustrates that the nano material sheets can be highly dispersed in the PE by the method of example 1, and further, the tensile strength and the impact strength can be improved.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. The PE nano composite material is characterized by being prepared by melting and blending mixed materials; the mixture comprises PE, wherein nano materials and a liquid medium are combined on PE particles, the liquid medium is dispersed among the nano materials to form a paste with certain self-adhesiveness, and the consistency of the paste is 0-100mm but not 0;

the nano material is selected from one or more of a flaky nano material, a fibrous nano material and a granular nano material;

the PE nano composite material is prepared by the following method:

A. mixing and stirring the nano material, the auxiliary agent and a liquid medium to form a paste; wherein, 1 weight part of nano material, 5 to 100 weight parts of liquid medium and 0 to 50 weight parts of auxiliary agent; the boiling point of the liquid medium is lower than the plasticizing temperature of the PE; the liquid medium is water;

in the step A, the dispersion of a liquid medium among the nano materials is promoted by a physical mode, wherein the physical mode comprises colloid milling, ball milling, ultrasonic, vortex, etching assistance and airflow impact;

adding latex in the step A, wherein the latex is selected from one or more of styrene-acrylic emulsion, silicone-acrylic emulsion, aqueous polyurethane emulsion, fluorocarbon emulsion, rosin resin emulsion, terpineol, vinyl acetate-acrylic emulsion, aqueous epoxy resin emulsion, styrene-butadiene latex, natural latex, white latex, chloroprene latex and carboxyl styrene-butadiene latex;

B. mixing and stirring the paste in the step A and the PE particles to form a blend; the mass part ratio of the nano material to the PE particles is 0.1-20: 100;

C. melting and blending the blend obtained in the step B to obtain the PE nano composite material;

in the step C, when the mixed materials are melted and blended and the temperature is higher than or equal to the PE plasticizing temperature, the liquid medium in the paste is further gasified, and the agglomerated nanometer materials are separated.

2. The PE nanocomposite material as claimed in claim 1, wherein the nanomaterial is selected from one or more of nano silicon oxide, nano zinc oxide, carbon nanofiber, nano tungsten oxide, and nano silicon.

3. The PE nanocomposite of claim 1, wherein the auxiliary agent is selected from one or more of a carboxylate surfactant, a sulfate surfactant, a sulfonate surfactant, a phosphate surfactant, an amine salt surfactant, a quaternary ammonium salt surfactant, a heterocyclic surfactant, a nonionic surfactant, a natural water soluble polymer, a synthetic water soluble polymer, and a prepolymer thereof.

4. The PE nanocomposite material as claimed in claim 3, wherein the mass part ratio of the auxiliary agent to the nanomaterial is 0.01-50: 1.

5. The PE nanocomposite material as claimed in claim 4, wherein an anti-aging agent is further added to the mixture, and the mass part ratio of the anti-aging agent to the PE is 0.1-1: 100.

6. A process for the preparation of a PE nanocomposite according to any one of claims 1 to 5, comprising the steps of:

7. The method of claim 6, wherein the auxiliary is added at one time or in batches.

8. The method for preparing PE nano composite material according to claim 6, wherein the step C comprises:

(1) heating, and mixing and contacting the PE with the liquid medium and the nano material in the paste under first stirring, softening, mutually permeating and coating;

(2) and after the temperature is higher than the boiling point of the liquid medium, partially gasifying the liquid medium, and carrying out secondary stirring on the mixed material by gasifying.

9. The method of claim 8, wherein the PE nanocomposite material,

in the step C, when the mixed materials are melted and blended, the liquid medium is gasified to promote the fluidity of the mixed materials and the conduction of heat, the liquid medium is gasified to soften the hot PE, and the plasticizing temperature of the hot PE is reduced.