WO2018045671A1

WO2018045671A1 - Nanomaterial film with high ultraviolet shielding and high barrier properties and preparation method therefor

Info

Publication number: WO2018045671A1
Application number: PCT/CN2016/111410
Authority: WO
Inventors: 郑玉婴; 陈宇
Original assignee: 福州大学
Priority date: 2016-09-12
Filing date: 2016-12-22
Publication date: 2018-03-15
Also published as: CN106317578A

Abstract

The present invention relates to the field of polymer material preparation. Disclosed are a nanomaterial film with high ultraviolet shielding and high barrier properties and a preparation method therefor. First, ethanolamine functionalized graphene nanoribbons are dispersed in a low-density polyethylene (LDPE) matrix to produce masterbatch; the masterbatch is mixed with LDPE granules according to a mass ratio of 1:1, and then the mixture is extruded, pelletized, sheeted and cut to obtain a nanomaterial film. In the nanomaterial film, the ethanolamine functionalized graphene nanoribbons account for 0.2%-1.5% by weight of the LDPE matrix. Graphene oxide nanoribbons in the present invention are modified with ethanolamine, so that the solubility of the nanoribbons in an organic solvent is improved, and the nanoribbons can be evenly dispersed in the LDPE matrix. By closely bonding ethanolamine functionalized graphene nanoribbon intercalation with the LDPE matrix, the composite material has an excellent barrier property. The introduction of the ethanolamine greatly improves the ultraviolet shielding property of the composite film. Therefore, the film can be applied in the field of ultraviolet shielding and barrier packaging films and has broad application prospects.

Description

High ultraviolet shielding high barrier nano material film and preparation method thereof

Technical field

The invention belongs to the technical field of polymer material preparation, and particularly relates to a high ultraviolet shielding high barrier nano material film and a preparation method thereof.

Background technique

Polyethylene (PE) is a thermoplastic resin obtained by polymerization of ethylene. It has a simple structure and is the most widely used polymer material. Polyethylene is non-toxic and odorless, has excellent high stretchability, low temperature resistance, good chemical stability, and is resistant to most acid and alkali attack. It is widely used in industry, agriculture, packaging and daily industry, and is widely used in China. . However, the shortcoming of the polyethylene film is that some small molecules such as oxygen, water vapor and the like easily permeate, and the ultraviolet rays are easily penetrated in the past, which greatly limits the application of the PE film material in ultraviolet shielding and barrier. Therefore, further improving the performance of PE and making it functional is the focus of research.

In order to improve the UV shielding performance and barrier properties of the film material, it is considered to uniformly disperse an appropriate amount of the filler having high performance efficiency in the TPU matrix, so that the film achieves the desired effect. Graphene nanoribbons (GNRs) are thin ribbon-like structural materials mainly composed of carbon atoms, which can be regarded as a special structural two-dimensional variant of graphene. In addition to the excellent physical, chemical and mechanical properties of graphene, GNRs are superior to graphene due to their high aspect ratio and stability to small molecular substances such as water, high specific surface area, low defects and adjustable morphology. The ability to improve polymer barrier has broad application prospects.

In the invention, the ethanolamine functionalized graphene nanobelt is dispersed in the LDPE resin matrix, melt-extruded and granulated in a twin-screw extruder, and finally the EGNRs/LDPE composite film is prepared by tableting using a flat vulcanizer. The performance of the study, the introduction of ethanolamine greatly enhanced the UV shielding properties of the composite film and the dispersion of graphene nanoribbons in the matrix; the prepared EGNRs / LDPE composite film has excellent UV shielding and barrier properties, thus The invention has innovative value in academics and has wide social benefits in practical applications.

Summary of the invention

The object of the present invention is to provide a high ultraviolet shielding high barrier nano material film and a preparation method thereof according to the deficiencies of the prior art. The invention combines the intercalation of EGNRs with the LDPE matrix to make the composite film have excellent UV shielding properties and barrier properties.

To achieve the object of the present invention, the following technical solutions are adopted:

A preparation method of high ultraviolet shielding high barrier nano material film: dispersing ethanolamine functionalized graphene nanobelts (EGNRs) in a low density polyethylene matrix to prepare a masterbatch; masterbatch and low density polyethylene pellets according to 1 :1 quality ratio After the combination, the nano material film is obtained by extrusion granulation and tablet cutting; in the nano material film, the ethanolamine functionalized graphene nanoribbon occupies 0.2% to 1.5% of the low density polyethylene matrix.

The preparation method of the ethanolamine functionalized graphene nanobelt is as follows: the graphene oxide nanobelts (GONRs) and the ethanolamine are reacted at 25 ° C for 24 hours, and then freeze-dried to obtain modified graphene oxide nanobelts (EGONRs); The graphene oxide nanobelts were uniformly dispersed in deionized water, added with hydrazine hydrate, and reacted at 100 ° C for 6 h to prepare ethanolamine functionalized graphene nanobelts (EGNRs).

The low density polyethylene matrix has a melt index value of from 1.0 to 3.0 g/10 min, preferably from 1.5 to 2.0 g/10 min.

The preparation method of the high ultraviolet shielding high barrier nano material film: dispersing the ethanolamine functionalized graphene nanobelt in xylene, ultrasonically forming a uniformly dispersed nano solution; then adding low density polyethylene and heating to 80 ° C Stirring to a paste-like liquid; then pouring the paste liquid into absolute ethanol, stirring and flocculation, filtering and drying to obtain a masterbatch; then, the masterbatch and the low-density polyethylene pellets are added to the twin-screw at a mass ratio of 1:1. The melt-extruded granulation was carried out in the machine, and finally the nano-material film was prepared by tableting with a flat vulcanizing machine; the concentration of the ethanolamine functionalized graphene nanobelt in the nano-solution was 0.002 mg·mL ^-1 ; the melting temperature was 140 ° C.

A high ultraviolet shielding high barrier nano material film prepared by the preparation method as described above.

The functionalized nano material film material prepared by the method of the invention has excellent ultraviolet shielding performance and barrier property, and can be applied in the ultraviolet release workshop, the sunshade device and the packaging in actual production, and has broad practical application value.

The beneficial effects of the invention are:

1) The ethanolamine functionalized graphene nanobelts obtained by hydrazine hydrazine reduction have excellent aspect ratio, low defect and compact structure. On the one hand, the introduction of ethanolamine improves the lipophilicity of graphene nanoribbons and realizes its Uniform dispersion in xylene, good compatibility with low density polyethylene matrix, providing a basis for the preparation of composite film; on the other hand, the introduction of ethanolamine, due to the unique properties of ethanol aminated graphene nanoribbons and even distribution in the matrix Provides a basis for excellent UV shielding and barrier properties, greatly enhancing the UV shielding properties of composite nanomaterial films;

2) The preparation method of the invention is scientific and reasonable, the process is simple, and the operability is strong. The preparation of the LDPE composite nano material film is safe and environmentally friendly, has excellent ultraviolet shielding performance and barrier property, and can be applied in the ultraviolet release workshop and the sunshade device in actual production. In terms of packaging and packaging, the added value of the product has been greatly expanded, and the application range of the LDPE film has been greatly expanded, and has broad market prospects and significant social and economic benefits.

DRAWINGS

Figure 1A is an FTIR spectrum of (a) GONRs, (b) EGONRs and (c) EGNRs;

1B is a dispersion diagram of (1) GONRs, (2) EGONRs, and (3) EGNRs in xylene (solution concentration is 0.5 mg·mL ^-1 , after standing for 15 days);

Figure 2 is a scanning electron microscope analysis (SEM) of the EGNRs/LDPE nanomaterial film samples after quenching of the quenched section;

3 is a graph showing changes in oxygen transmission rate of a pure LDPE film and a LDPE nano material film when different nanofillers are added;

Figure 4 is a graph showing the UV transmittance of a pure LDPE film and a LDPE nanomaterial film with different nanofillers added.

detailed description

In order to further disclose, not limit the invention, the invention will be further described in detail in the following examples.

A method for high-ultraviolet shielding high-barrier nano material film, the specific steps are as follows:

(1) Preparation of GONRs: First, 180 mL of concentrated H ₂ SO ₄ was slowly added to a round bottom flask and stirred, and then 20 mL of H ₃ PO _{4 was} slowly dropped, mixed uniformly at a certain rotation speed, and 1 g of MWCNTs was slowly added. After stirring for 30 min to homogeneity, 6 g of KMnO ₄ was slowly added to the above mixture; the above reaction system was stirred in an oil bath at 50 ° C for 24 h, then cooled to room temperature, and then poured into 500 mL of 10 mL H ₂ O ₂ . Deionized water was stirred in an ice bath for 1 h, at which time the solution became dark green, indicating that the reaction was sufficient, then adding an appropriate amount of HCl to centrifuge to neutrality, and finally drying in a freeze dryer to obtain GONRs;

(2) Preparation of EGONRs: 100 mg GONRs were dissolved in 100 mL of deionized water, 100 W ultrasonic for 1 h to form a uniform dispersion; a certain amount of HCl was added to adjust the pH to 1-2; then 0.5 g of ethanolamine was added to react at room temperature for 24 h to obtain a black paste. The product is washed several times with absolute ethanol and deionized water to remove the remaining ethanolamine and HCl, and finally dried in a freeze dryer to obtain EGONRs;

(3) Preparation of EGNRs: 100mg EGONRs were dissolved in 100mL deionized water, 100W ultrasonic for 1h to form a uniform dispersion, 1g hydrated hydrazine was added, and reduced at 100 °C for 6h; the obtained black paste product, with absolute ethanol and deionized Washing the water several times to remove the remaining hydrazine hydrate, and finally drying in a freeze dryer to obtain EGNRs;

(4) Preparation of EGNRs/LDPE composite film: 5 g of LDPE was placed in a round bottom flask, 30 mL of xylene was added, the temperature was raised to 80 ° C and stirred to a paste liquid, and 0.05 g of EGNRs was dissolved in 10 mL of xylene, and then slowly. Pour into a round bottom flask and stir evenly at a certain speed; slowly pour the mixture into a large amount of absolute ethanol, stir and flocculate, filter and dry to obtain EGNRs/LDPE masterbatch; then obtain the obtained EGNRs/LDPE masterbatch The LDPE pellets were melted and extruded at 140 °C in a 1:1 twin-screw extruder. Finally, the EGNRs/LDPE composite film with a thickness of 0.5 mm was prepared by tableting with a flat vulcanizer. .

Comparative example 1

5 g of LDPE was placed in a round bottom flask, 30 mL of xylene was added, the temperature was raised to 80 ° C and stirred to a paste liquid, and the paste liquid was slowly poured into a large amount of absolute ethanol, stirred and flocculated, filtered and dried to obtain a LDPE mother. Material; subsequent income The LDPE masterbatch and the LDPE pellets were fed into a twin-screw extruder at a ratio of 1:1 to melt and extrude at 140 ° C. Finally, a LDPE film having a thickness of 0.5 mm was prepared by tableting using a flat vulcanizer.

Example 1

5 g of LDPE was placed in a round bottom flask, 30 mL of xylene was added, the temperature was raised to 80 ° C and stirred until a paste; 0.05 g of EGNRs was dissolved in 10 mL of xylene, slowly poured into a round bottom flask, and stirred uniformly; The solution was slowly poured into a large amount of absolute ethanol, stirred and flocculated, filtered and dried to obtain an EGNRs/LDPE masterbatch, and then the obtained EGNRs/LDPE masterbatch and LDPE pellets were fed into a twin-screw extruder at 1:1 at 140. The melt-extruded granulation was carried out at ° C. Finally, a 0.5 wt% EGNRs/LDPE composite film was prepared by tableting using a flat vulcanizer.

Example 2

12.5 g of LDPE was placed in a round bottom flask, 60 mL of xylene was added, the temperature was raised to 80 ° C and stirred until a paste; 0.05 g of EGNRs was dissolved in 10 mL of xylene, slowly poured into a round bottom flask, and stirred uniformly; The mixture was slowly poured into a large amount of absolute ethanol, stirred and flocculated, filtered and dried to obtain an EGNRs/LDPE masterbatch, and then the obtained EGNRs/LDPE masterbatch and LDPE pellets were added to the twin-screw extruder at 1:1. The melt-extruded granulation was carried out at 140 ° C. Finally, a 0.2 wt% EGNRs/LDPE composite film was prepared by tableting using a flat vulcanizer.

Example 3

6.25 g of LDPE was placed in a round bottom flask, 40 mL of xylene was added, the temperature was raised to 80 ° C and stirred until a paste; 0.05 g of EGNRs was dissolved in 10 mL of xylene, slowly poured into a round bottom flask, and stirred evenly; The mixture was slowly poured into a large amount of absolute ethanol, stirred and flocculated, filtered and dried to obtain an EGNRs/LDPE masterbatch; then the obtained EGNRs/LDPE masterbatch and LDPE pellets were added to the twin-screw extruder at 1:1. Melt extrusion granulation at 140 ° C, and finally 0.4 wt% EGNRs / LDPE composite film was prepared by tablet cutting using a flat vulcanizer.

Example 4

4.17 g of LDPE was placed in a round bottom flask, 30 mL of xylene was added, the temperature was raised to 80 ° C and stirred until a paste; 0.05 g of EGNRs was dissolved in 10 mL of xylene, slowly poured into a round bottom flask, and stirred uniformly; The mixture was slowly poured into a large amount of absolute ethanol, stirred and flocculated, filtered and dried to obtain an EGNRs/LDPE masterbatch; then the obtained EGNRs/LDPE masterbatch and LDPE pellets were added to the twin-screw extruder at 1:1. The melt-extruded granulation was carried out at 140 ° C, and finally a 0.6 wt% EGNRs/LDPE composite film was prepared by tableting using a flat vulcanizer.

Example 5

3.125 g of LDPE was placed in a round bottom flask, 30 mL of xylene was added, the temperature was raised to 80 ° C and stirred until a paste; 0.05 g of EGNRs was dissolved in 10 mL of xylene, slowly poured into a round bottom flask, and stirred uniformly; The mixture is slowly poured into a large amount of absolute ethanol, stirred and flocculated, filtered and dried to obtain an EGNRs/LDPE masterbatch; The EGNRs/LDPE masterbatch and LDPE pellets were melted and extruded at 140 °C in a 1:1 twin-screw extruder. Finally, a 0.8 wt% EGNRs/LDPE composite was prepared by tableting with a flat vulcanizer. film.

Example 6

2.5 g of LDPE was placed in a round bottom flask, 30 mL of xylene was added, the temperature was raised to 80 ° C and stirred until a paste; 0.05 g of EGNRs was dissolved in 10 mL of xylene, slowly poured into a round bottom flask, and stirred uniformly; The mixture was slowly poured into a large amount of absolute ethanol, stirred and flocculated, filtered and dried to obtain an EGNRs/LDPE masterbatch; then the obtained EGNRs/LDPE masterbatch and LDPE pellets were added to the twin-screw extruder at 1:1. The melt-extruded granulation was carried out at 140 ° C, and finally a 1.0 wt% EGNRs/LDPE composite film was prepared by tableting using a flat vulcanizer.

Example 7

1.7 g of LDPE was placed in a round bottom flask, 30 mL of xylene was added, the temperature was raised to 80 ° C and stirred until a paste; 0.05 g of EGNRs was dissolved in 10 mL of xylene, slowly poured into a round bottom flask, and stirred uniformly; The mixture was slowly poured into a large amount of absolute ethanol, stirred and flocculated, filtered and dried to obtain an EGNRs/LDPE masterbatch; then the obtained EGNRs/LDPE masterbatch and LDPE pellets were added to the twin-screw extruder at 1:1. The melt-extruded granulation was carried out at 140 ° C. Finally, a 1.5 wt% EGNRs/LDPE composite film was prepared by tableting using a flat vulcanizer.

Claims

A method for preparing a high-ultraviolet-shielding high-barrier nano material film, characterized in that: an ethanolamine functionalized graphene nanobelt is dispersed in a low-density polyethylene matrix to prepare a masterbatch; and a masterbatch and a low-density polyethylene pellet are pressed After mixing 1:1 mass ratio, the nano material film is obtained by extrusion granulation and tablet cutting; in the nano material film, the ethanolamine functionalized graphene nanoribbon occupies 0.2% of the low density polyethylene matrix. ~1.5%.
The method for preparing a high-ultraviolet-shielding high-barrier nano-material film according to claim 1, wherein the ethanolamine functionalized graphene nanoribbon is prepared by: graphene oxide nanobelts and ethanolamine at 25 ° C After 24 hours of reaction, the modified graphene oxide nanobelts were obtained by freeze-drying; the modified graphene oxide nanobelts were uniformly dispersed in deionized water, and hydrazine hydrate was added thereto, and reacted at 100 ° C for 6 h to prepare an ethanolamine functionalized graphene nanobelt.
The method for preparing a high ultraviolet shielding high barrier nano material film according to claim 1, wherein the low density polyethylene substrate has a melt index value of 1.0 to 3.0 g/10 min.
The method for preparing a high ultraviolet shielding high barrier nano material film according to claim 1, wherein the ethanolamine functionalized graphene nanobelt is dispersed in xylene, ultrasonically forms a uniformly dispersed nano solution; and then low density is added. Polyethylene, and heated to 80 ° C, stirred to a paste liquid; then the paste liquid was poured into absolute ethanol, stirred and flocculated, filtered and dried to obtain a masterbatch; then the masterbatch and low density polyethylene pellets by mass The melt extrusion granulation was carried out in a twin-screw extruder at a ratio of 1:1, and finally a nanomaterial film was prepared by tableting using a flat vulcanizer.
The method for preparing a high ultraviolet shielding high barrier nano material film according to claim 1, wherein the concentration of the ethanolamine functionalized graphene nanobelt in the nano solution is 0.002 mg·mL -1 .
The method for preparing a high ultraviolet shielding high barrier nano material film according to claim 1, wherein the melting temperature is 140 °C.
A high ultraviolet shielding high barrier nano material film obtained by the preparation method according to any one of claims 1 to 6.