阅读说明：本技术 一种石墨烯防水透气膜 (Waterproof ventilated membrane of graphite alkene ) 是由 晁磊 周如鸿 张俊武 于 2020-07-17 设计创作，主要内容包括：本发明提供了一种石墨烯防水透气膜,通过以下步骤进行制备：S1、制备石墨烯分散液；S2、制备石墨烯/聚乙烯预分散体：取5-10份的聚乙烯,加入10倍于聚乙烯的溶剂,升温至120-160℃,待完全溶解后形成聚乙烯热熔物,加入所述石墨烯分散液,搅拌混合2-4h,形成石墨烯/聚乙烯混合热熔液,将所述石墨烯/聚乙烯混合热熔液缓慢倒入溶剂中并快速搅拌,待完全析出后,抽滤,洗涤,真空干燥,得到粉末状的石墨烯/聚乙烯预分散体；S3、制备石墨烯防水透气膜。这种石墨烯防水透气膜采用预分散方式,有效解决石墨烯片层团聚问题,石墨烯较薄片层插层到聚乙烯链中,减少透气膜的厚度。石墨烯充当无机材料的作用,提高断裂强度和断裂伸长率,增加透气性。(The invention provides a graphene waterproof breathable film which is prepared by the following steps: s1, preparing a graphene dispersion liquid; s2, preparing a graphene/polyethylene pre-dispersion: adding 5-10 parts of polyethylene into a solvent which is 10 times that of the polyethylene, heating to 120-160 ℃, forming a polyethylene hot melt after completely dissolving, adding the graphene dispersion liquid, stirring and mixing for 2-4 hours to form a graphene/polyethylene mixed hot melt, slowly pouring the graphene/polyethylene mixed hot melt into the solvent and quickly stirring, after completely separating out, performing suction filtration, washing, and vacuum drying to obtain a powdery graphene/polyethylene pre-dispersion; s3, preparing the graphene waterproof breathable film. The graphene waterproof breathable film adopts a pre-dispersion mode, the problem of graphene sheet layer agglomeration is effectively solved, and graphene is intercalated into a polyethylene chain compared with a sheet layer, so that the thickness of the breathable film is reduced. The graphene serves as an inorganic material, so that the breaking strength and the breaking elongation are improved, and the air permeability is improved.)

1. The graphene waterproof breathable film is characterized by being prepared through the following steps:

s1, preparing a graphene dispersion liquid: adding 1-2 parts of dispersing agent into a solvent, uniformly stirring, adding 2-10 parts of graphene and 1-2 parts of coupling agent, ultrasonically dispersing for 1-3h, adding a pH regulator, controlling the pH value of a reaction system, heating for reaction for 4-12h, performing suction filtration after the reaction is finished, washing with the solvent, drying, and dispersing into the solvent again to obtain graphene dispersion liquid;

s2, preparing a graphene/polyethylene pre-dispersion: adding 5-10 parts of polyethylene into a solvent which is 10 times that of the polyethylene, heating to 120-160 ℃, forming a polyethylene hot melt after completely dissolving, adding the graphene dispersion liquid, stirring and mixing for 2-4 hours to form a graphene/polyethylene mixed hot melt, slowly pouring the graphene/polyethylene mixed hot melt into the solvent and quickly stirring, after completely separating out, performing suction filtration, washing, and vacuum drying to obtain a powdery graphene/polyethylene pre-dispersion;

s3, preparing a graphene waterproof breathable film: 30-60 parts of polyethylene, 0.1-0.5 part of pigment, 0.5-5 parts of nano inorganic filler, 0.1-0.8 part of auxiliary agent and the graphene/polyethylene pre-dispersion are mixed, stirred and mixed uniformly, put into a double-screw extruder for melting granulation, then cast into a film-forming base material through a casting machine, thermally stretch the film-forming base material to form nano micropores, and finally, thermally set, cool and corona are carried out to obtain the graphene waterproof breathable film.

2. The graphene waterproof and breathable film according to claim 1, wherein the controlling of the pH value of the reaction system in the step S1 is specifically:

firstly, adjusting the pH value of a reaction system to be weakly acidic, reacting for 4-6 h at the temperature of 60-80 ℃,

and secondly, adjusting the pH value of the reaction system to be alkaline, heating to 90-140 ℃, and reacting for 6-8 h.

3. The graphene waterproof breathable film of claim 1, wherein:

the drying temperature in the step S1 is less than 40 ℃; the drying temperature in the step S2 is 60-80 ℃, and the drying time is 24 h; in the step S3, the temperature of hot stretching is 80-90 ℃, and the temperature of heat setting is 90-105 ℃.

4. The graphene waterproof breathable film of claim 1, wherein:

in the step S2, the stirring speed when the graphene/polyethylene mixed hot melt is slowly poured into the solvent is 1000-1500 r/min.

5. The graphene waterproof breathable film of claim 1, wherein:

the dispersing agent is one or more of BYK163, Winsperse-3050, Silok-7096, Silok-7679 and Anti-Terra 250.

6. The graphene waterproof breathable film of claim 1, wherein: the graphene has less than 20 sheets.

7. The graphene waterproof breathable film of claim 1, wherein: the pH regulator is one or more of glacial acetic acid, hydrochloric acid, ammonia water and urea; the coupling agent is one or more of silane coupling agent, titanate coupling agent, organic chromium complex coupling agent and aluminate coupling agent.

8. The graphene waterproof breathable film of claim 1, wherein: the solvent is one or more of ethanol, toluene, xylene, acetone, dichloromethane and chloroform.

9. The graphene waterproof breathable film of claim 1, wherein: the polyethylene is one or more of high-density polyethylene, ultrahigh molecular weight polyethylene, linear low-density polyethylene and very low-density polyethylene.

10. The graphene waterproof breathable film of claim 1, wherein: the nano inorganic filler is nano calcium carbonate with the particle size of 2-20 nm.

Technical Field

The invention relates to the technical field of breathable films, and particularly relates to a graphene waterproof breathable film.

Background

The polyethylene waterproof breathable film is widely applied to sanitary products such as baby diapers, sanitary towels and nursing mattresses, and compared with airtight film products, the polyethylene breathable film is not easy to generate moisture on the surface of skin, so that the incidence rate of dermatitis is reduced. Meanwhile, the polyethylene film also has certain elasticity, can deform adaptively according to the activity of human body, and improves the use comfort.

The polyethylene waterproof breathable film is generally added with a certain proportion of superfine inorganic filler (such as calcium carbonate) in the production process, micropores are formed after the treatment of the tape casting stretching process, and the distribution of the micropores is wider, so that the polyethylene film has a certain water vapor transmission capacity, and water molecules with larger sizes can be intercepted. However, the addition of calcium carbonate having a spherical structure is likely to cause a decrease in the tensile strength of the material. The commonly used modified material at present is talcum powder, and the tensile strength, rigidity and other properties of the material are improved to a certain extent. What is not negligible is that the addition of talcum powder virtually increases the thickness of the membrane, reduces the air permeability, reduces the comfort and has certain toxic and side effects.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: in order to solve the above problems in the prior art, the present invention provides a graphene waterproof breathable film to solve the above problems.

The technical scheme adopted by the invention for solving the technical problems is as follows: a graphene waterproof breathable film is prepared by the following steps:

s1, preparing a graphene dispersion liquid: adding 1-2 parts of dispersing agent into a solvent, uniformly stirring, adding 2-10 parts of graphene and 1-2 parts of coupling agent, ultrasonically dispersing for 1-3h, adding a pH regulator, controlling the pH value of a reaction system, heating for reaction for 4-12h, performing suction filtration after the reaction is finished, washing with the solvent, drying, and dispersing into the solvent again to obtain graphene dispersion liquid;

s2, preparing a graphene/polyethylene pre-dispersion: adding 5-10 parts of polyethylene into a solvent which is 10 times that of the polyethylene, heating to 120-160 ℃, forming a polyethylene hot melt after completely dissolving, adding the graphene dispersion liquid, stirring and mixing for 2-4 hours to form a graphene/polyethylene mixed hot melt, slowly pouring the graphene/polyethylene mixed hot melt into the solvent and quickly stirring, after completely separating out, performing suction filtration, washing, and vacuum drying to obtain a powdery graphene/polyethylene pre-dispersion;

s3, preparing a graphene waterproof breathable film: 30-60 parts of polyethylene, 0.1-0.5 part of pigment, 0.5-5 parts of nano inorganic filler, 0.1-0.8 part of auxiliary agent and the graphene/polyethylene pre-dispersion are mixed, stirred and mixed uniformly, put into a double-screw extruder for melting granulation, then cast into a film-forming base material through a casting machine, thermally stretch the film-forming base material to form nano micropores, and finally, thermally set, cool and corona are carried out to obtain the graphene waterproof breathable film.

Preferably, the controlling of the pH of the reaction system in the step S1 is specifically:

firstly, adjusting the pH value of a reaction system to be weakly acidic, reacting for 4-6 h at the temperature of 60-80 ℃,

and secondly, adjusting the pH value of the reaction system to be alkaline, heating to 90-140 ℃, and reacting for 6-8 h.

Preferably, the drying temperature in the step S1 is less than 40 ℃; the drying temperature in the step S2 is 60-80 ℃, and the drying time is 24 h; in the step S3, the temperature of hot stretching is 80-90 ℃, and the temperature of heat setting is 90-105 ℃.

Preferably, the stirring speed when the graphene/polyethylene mixed hot melt is slowly poured into the solvent in the step S2 is 1000-1500 r/min.

Preferably, the dispersing agent is one or more of BYK163, Winsperse-3050, Silok-7096, Silok-7679 and Anti-Terra 250.

Preferably, the graphene has less than 20 sheets.

Preferably, the pH regulator is one or more of glacial acetic acid, hydrochloric acid, ammonia water and urea; the coupling agent is one or more of silane coupling agent, titanate coupling agent, organic chromium complex coupling agent and aluminate coupling agent.

Preferably, the solvent is one or more of ethanol, toluene, xylene, acetone, dichloromethane and chloroform.

Preferably, the polyethylene is one or more of high-density polyethylene, ultrahigh molecular weight polyethylene, linear low-density polyethylene and very low-density polyethylene.

Preferably, the nano inorganic filler is nano calcium carbonate, and the particle size is 2-20 nm.

The graphene waterproof breathable film has the beneficial effects that the graphene waterproof breathable film adopts a pre-dispersion mode, the problem of graphene sheet layer agglomeration is effectively solved, graphene is intercalated into a polyethylene chain in comparison with a sheet layer, the graphene is uniformly dispersed in a polyethylene material, and the thickness of the breathable film is reduced. The graphene serves as an inorganic material, the using amount of calcium carbonate is reduced, nano gaps are formed in the polyethylene stretching process, the excellent mechanical property of the graphene is realized, the toughness of the film is improved, the breaking strength and the breaking elongation are improved, and the air permeability is improved.

Drawings

The invention is further illustrated with reference to the following figures and examples.

In fig. 1, (a) shows the dispersion of graphene after ultrasonic treatment, and (b) shows the dispersion of graphene after standing for more than one week

FIG. 2 is a graphene/polyethylene pre-dispersion after drying

Fig. 3 is a comparison of the mechanical tensile properties of polyethylene film and graphene waterproof breathable film.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.