阅读说明：本技术 一种纤维素复合防水薄膜及其制备方法 (Cellulose composite waterproof film and preparation method thereof ) 是由 胡金莲 石朔 朱坤坤 于 2019-09-16 设计创作，主要内容包括：本发明提供了一种纤维素复合防水薄膜,由70～100重量份的纤维素浆、0～20重量份的超细功能材料以及0～10重量份的助剂制备得到；本申请还提供了所述纤维素复合防水薄膜的制备方法,其依次经过了原料混合、低温溶解、消泡、成膜和凝固浴,最终得到了厚度为0.01mm～0.05mm的纤维素复合防水薄膜。本发明制备得到的薄膜的透湿量大于10000g·m<Sup>2</Sup>/24h,并具有较高拉伸断裂强度和耐静水压。该纤维素复合防水透膜在防水透湿衣物、建筑结构布膜和智能可穿戴等领域具有广泛应用前景。(The invention provides a fiberThe element composite waterproof film is prepared from 70-100 parts by weight of cellulose pulp, 0-20 parts by weight of superfine functional material and 0-10 parts by weight of auxiliary agent; the application also provides a preparation method of the cellulose composite waterproof film, which comprises the steps of raw material mixing, low-temperature dissolution, defoaming, film forming and coagulating bath in sequence, and finally the cellulose composite waterproof film with the thickness of 0.01-0.05 mm is obtained. The moisture permeability of the film prepared by the invention is more than 10000 g.m 2 24h, and has higher tensile breaking strength and hydrostatic pressure resistance. The cellulose composite waterproof permeable membrane has wide application prospect in the fields of waterproof and moisture permeable clothes, building structure cloth membranes, intelligent wearable clothes and the like.)

1. A cellulose composite waterproof film is prepared from 70-100 parts by weight of cellulose pulp, 0-20 parts by weight of superfine functional material and 0-10 parts by weight of auxiliary agent;

the content of the superfine functional material is not 0, the superfine functional material is one or more of superfine functional powder and modified superfine functional powder, and the superfine functional powder is selected from one or more of silicon carbide superfine powder, silicon carbide aerogel, calcium carbonate superfine powder, carbon black superfine powder, carbon aerogel, silica superfine powder, silica aerogel, titanium dioxide superfine powder, titanium dioxide aerogel, talcum powder, mica powder, feldspar powder, barium sulfate superfine powder, wollastonite superfine powder, magnesium hydroxide superfine powder and micro-silicon superfine powder.

2. The cellulose composite waterproof film according to claim 1, wherein the size of the superfine functional material is 0.1-10 μm.

3. The cellulose composite waterproof film according to claim 1, wherein the cellulose pulp is contained in an amount of 75 to 90 parts by weight, and the ultrafine functional material is contained in an amount of 1 to 10 parts by weight.

4. The cellulose composite waterproof film according to claim 1, wherein the cellulose pulp is one or more selected from the group consisting of absorbent cotton, wood pulp, straw, rice bran, sugar cane straw, hemp, and reed straw.

5. The cellulose composite waterproof film according to claim 1, wherein the auxiliary agent is one or more selected from a group consisting of a defoaming agent, an antioxidant, a flame retardant, a mold release agent, a leveling agent, a light stabilizer, an antistatic agent, a mildewproof agent and a crosslinking agent.

6. The cellulose composite waterproof film according to claim 1, wherein the waterproof film has a thickness of 0.01 to 0.05mm and a moisture permeability of > 10000 g-m²/24h。

7. the method for preparing the cellulose composite waterproof film as claimed in claim 1, comprising the steps of:

A) Dissolving 70-100 parts by weight of cellulose pulp, 0-20 parts by weight of superfine functional material and 0-10 parts by weight of auxiliary agent in a solution, and stirring to obtain a cellulose solution;

B) defoaming the cellulose solution, and forming a film to obtain a cellulose initial film;

C) Solidifying and exchanging the cellulose initial film in a coagulating bath, and drying to obtain a cellulose composite waterproof film;

The content of the superfine functional material is not 0, the superfine functional material is one or more of superfine functional powder and modified superfine functional powder, and the superfine functional powder is selected from one or more of silicon carbide superfine powder, silicon carbide aerogel, calcium carbonate superfine powder, carbon black superfine powder, carbon aerogel, silica superfine powder, silica aerogel, titanium dioxide superfine powder, titanium dioxide aerogel, talcum powder, mica powder, feldspar powder, barium sulfate superfine powder, wollastonite superfine powder, magnesium hydroxide superfine powder and micro-silicon superfine powder.

8. The method according to claim 7, wherein the solution is an aqueous solution of an alkali solution selected from one or more of a sodium oxide solution, a potassium hydroxide solution, a lithium hydroxide solution, an alkoxide solution, a lithium diisopropylamide solution, a proton sponge solution, and a Schloth alkali solution, and an amine selected from one or more of a methylamine solution, an ethylenediamine solution, a diisopropylamine solution, a triethanolamine solution, a tetrabutyl bromide solution, a urea solution, dimethylformamide, and dimethylacetamide.

9. The method according to claim 7, wherein the coagulation bath comprises water, N-dimethylformamide, dimethylacetamide, and 0.1 to 50.0 wt% Na₂SO₄0.1-50.0 wt% (NH)₄)₂SO₄The water solution of (A) and 0.1 to 99.9 weight percent of ethanol water solutionOne or more of liquid, 0.1-99.9 wt% methanol water solution and 0.1-50.0 wt% glycerin water solution, wherein the temperature of the coagulating bath is-5-99 ℃.

10. The production method according to claim 7, wherein the stirring is performed at a temperature of-5 ℃ to-50 ℃ to dissolve the cellulose.

Technical Field

The invention relates to the technical field of waterproof and moisture permeable films, in particular to a cellulose composite waterproof film and a preparation method thereof.

Background

the waterproof moisture permeable film material is a functional polymer material with good market prospect, and the market demand thereof is increasing day by day. At present, waterproof moisture permeable films on the market are various in types, and are mainly divided into two types according to the film structure and the moisture permeable principle: firstly, a porous waterproof moisture-permeable film; ② a waterproof film without holes.

The porous waterproof moisture-permeable film is a film containing a large number of micron-sized micropores (generally 0.5-20 microns), and selective permeability to water vapor is realized by controlling the size, the number and the arrangement of the micropores, so that the moisture absorption-moisture permeability effect of the film is realized. At present, the waterproof moisture-permeable film is represented by a polytetrafluoroethylene composite film, and has good moisture-permeable performance. Taking a commercial product Gore-Tex as an example,The moisture permeability of the 2-Layer is 25000 g.m²The fabric has good moisture permeability for 24h (T23 ℃, RH 50%, Standard-ASTM E96 BW), and is widely used in fabric products such as jacket, climbing wear and diving wear. However, the development and processing of tetrafluoroethylene have been monopolized by foreign enterprises for a long time, and the degradation difficulty of tetrafluoroethylene is high, and the long-term and large-scale use of tetrafluoroethylene has a bad influence on the environment, so the demand for developing a waterproof moisture-permeable film for replacing tetrafluoroethylene is urgent. In addition, the porous film requires a large amount of solvent in the processing process, easily causes environmental pollution, and causes excessive cost; moreover, the micropore preparation requires relatively more process flows, which results in complex production process and high equipment manufacturing and cost; finally, microporous films are very prone to adsorb fine particles such as smoke dust, fog and detergents during use, and especially cause blockage of micropores after long-term use or repeated washing, resulting in significant decrease in moisture permeability. Therefore, the above factors limit the range of application of the microporous waterproof moisture-permeable membrane.

The waterproof moisture-permeable film is a pore-free waterproof film, and the film is also called a hydrophilic film. It realizes the moisture absorption-moisture permeation function of the film by the adsorption-diffusion-desorption of hydrophilic groups in a high molecular chain segment, and the film of the type is generally represented by a hydrophilic polyester film and a polyurethane film. This is because the flexible designability of polyester reaction and polyurethane reaction is determined, and hydrophilic groups (such as ether group, amino group, hydroxyl group, carboxyl group, etc.) can be introduced into the molecular chain to improve the hydrophilic performance, thereby improving the moisture permeability. However, the pore-free waterproof moisture permeable film is limited by its moisture permeable principle (adsorption-diffusion-desorption of water molecules on hydrophilic groups of high molecules), so that the molecular structure design is complex, the synthesis steps are long, the process route and the equipment cost are high, the mechanical property of the prepared product is poor, and the high moisture permeable function is difficult to realize, so that the use and industrialization of the pore-free waterproof moisture permeable film are limited by the factors.

In view of the above prior art, the development of a high-performance waterproof moisture-permeable film is an urgent need in the field of waterproof moisture-permeable film research. Considering that the microporous waterproof moisture-permeable film is easy to adsorb microparticles in the using process, and the performance of the microporous waterproof moisture-permeable film is easy to reduce in the later using process, the preparation cost is high, and other factors, the microporous waterproof moisture-permeable film is considered to be a trend of future development, and the key factor for solving the high moisture-permeable performance of the microporous waterproof moisture-permeable film is to design and improve the content of hydrophilic groups in molecular chains.

In the traditional research, polyester and polyurethane molecular chains are mostly designed, so that the molecular structure is complex, the synthetic route is long, the process route cost is high, and the moisture permeability and the mechanical property of the prepared polyester and polyurethane film are not good. With DuPont ActiveFor example, the moisture permeability is 13000 to 15000 g.m²24h (T23 ℃, RH 50%, Standard-ASTM E96 BW), but the tensile breaking strength is only 14-15 MPa, the moisture permeability can meet the requirement of preparing the conventional waterproof moisture permeable clothes but because the strength is lower,thereby limiting its range of use.

in general, these studies neglected the existence of a large amount of substances containing groups of high hydrophilic type in the field of natural polymers, such as absorbent cotton, wood pulp, straw, rice bran, sugar cane straw, hemp, reed straw, etc. The substance has better hydrophilic performance because the structure contains a large amount of cellulose.

Cellulose (Cellulose) is the most abundant organic polymer on earth, is a polysaccharide which is widely distributed and has the highest content in nature, and is a main component for forming plant cell walls. The chemical formula of the cellulose is (C)₆H₁₀O₅)_nPolysaccharides are composed of linear chains (glycosidic linkages) of several hundred to several thousand D-glucose units. The molecular chain structure of the hydrophilic polymer contains a large number of hydroxyl groups and ether bonds, so that the hydrophilic polymer has good hydrophilic performance and a water molecule transfer function. Cotton, flax, ramie and jute have a large amount of high-quality cellulose. The cellulose content in cotton fiber is 90%, the cellulose content in wood is 40% -50%, and the cellulose content in dried hemp is 57%. In addition, wheat straw, paper pulp, rice straw, rice bran, sugarcane straw, reed straw and the like are rich sources of cellulose.

Therefore, the cellulose is utilized to obtain the waterproof moisture-permeable cellulose-based waterproof moisture-permeable film with excellent performance through proper chemical treatment and doping modification, the film is expected to become a waterproof moisture-permeable material with strong commercial prospect, and the film is applied to the fields of waterproof moisture-permeable clothes, building structure cloth films and intelligent wearable products.

Disclosure of Invention

The invention aims to provide a fiber composite waterproof film and a preparation method thereof, and the cellulose composite waterproof film provided by the application has the characteristics of controllable moisture permeability, larger moisture permeability, stronger mechanical property and higher hydrostatic pressure resistance.

In view of the above, the present application provides a cellulose composite waterproof film, which is prepared from 70 to 100 parts by weight of cellulose pulp, 0 to 20 parts by weight of an ultrafine functional material, and 0 to 10 parts by weight of an auxiliary agent;

the content of the superfine functional material is not 0, the superfine functional material is one or more of superfine functional powder and modified superfine functional powder, and the superfine functional powder is selected from one or more of silicon carbide superfine powder, silicon carbide aerogel, calcium carbonate superfine powder, carbon black superfine powder, carbon aerogel, silica superfine powder, silica aerogel, titanium dioxide superfine powder, titanium dioxide aerogel, talcum powder, mica powder, feldspar powder, barium sulfate superfine powder, wollastonite superfine powder, magnesium hydroxide superfine powder and micro-silicon superfine powder.

Preferably, the size of the superfine functional material is 0.1-10 μm.

Preferably, the content of the cellulose pulp is 75-90 parts by weight, and the content of the superfine functional material is 1-10 parts by weight.

Preferably, the cellulose pulp is selected from one or more of absorbent cotton, wood pulp, paper pulp, straw, rice bran, sugar cane straw, hemp, and reed straw.

preferably, the auxiliary agent is selected from one or more of a defoaming agent, an antioxidant, a flame retardant, a mold release agent, a leveling agent, a light stabilizer, an antistatic agent, a mildewproof agent and a crosslinking agent.

Preferably, the thickness of the waterproof film is 0.01-0.05 mm, and the moisture permeability is more than 10000 g.m²/24h。

the application also provides a preparation method of the cellulose composite waterproof film, which comprises the following steps:

A) dissolving 70-100 parts by weight of cellulose pulp, 0-20 parts by weight of superfine functional material and 0-10 parts by weight of auxiliary agent in a solution, and stirring to obtain a cellulose solution;

B) Defoaming the cellulose solution, and forming a film to obtain a cellulose initial film;

C) Solidifying and exchanging the cellulose initial film in a coagulating bath, and drying to obtain a cellulose composite waterproof film;

The content of the superfine functional material is not 0, the superfine functional material is one or more of superfine functional powder and modified superfine functional powder, and the superfine functional powder is selected from one or more of silicon carbide superfine powder, silicon carbide aerogel, calcium carbonate superfine powder, carbon black superfine powder, carbon aerogel, silica superfine powder, silica aerogel, titanium dioxide superfine powder, titanium dioxide aerogel, talcum powder, mica powder, feldspar powder, barium sulfate superfine powder, wollastonite superfine powder, magnesium hydroxide superfine powder and micro-silicon superfine powder.

Preferably, the solution is an aqueous solution of an alkali solution selected from one or more of a sodium oxide solution, a potassium hydroxide solution, a lithium hydroxide solution, an alkoxide solution, a lithium diisopropylamide solution, a proton sponge solution, and a schloth alkali solution, and an amine selected from one or more of a methylamine solution, an ethylenediamine solution, a diisopropylamine solution, a triethanolamine solution, a tetrabutyl bromide solution, a urea solution, dimethylformamide, and dimethylacetamide.

Preferably, the coagulating bath comprises water, N-dimethylformamide, dimethylacetamide, and 0.1-50.0 wt% of Na₂SO₄0.1-50.0 wt% (NH)₄)₂SO₄The temperature of the coagulating bath is-5 to 99 ℃, and the temperature of the coagulating bath is one or more of an aqueous solution of (1) to 99.9 wt% of ethanol, an aqueous solution of (0.1) to 99.9 wt% of methanol and an aqueous solution of (0.1) to 50.0 wt% of glycerol.

Preferably, the stirring is performed at a temperature of-5 ℃ to-50 ℃ to dissolve the cellulose.

The application provides a cellulose composite waterproof film which is prepared from 70-100 parts by weight of cellulose pulp, 0-20 parts by weight of superfine functional material and 0-10 parts by weight of auxiliary agent; because the cellulose molecular chain contains a large amount of hydrophilic groups and the superfine functional material adjusts the structure of the cellulose matrix, the cellulose composite waterproof film has excellent moisture permeability function, mechanical function and hydrostatic pressure resistance; simultaneously, the compound waterproof membrane of cellulose that this application provided does not have porous structure, consequently can not have the phenomenon of micropore jam in the later stage uses to the compound waterproof membrane of cellulose moisture transmission reduces's in having avoided the later stage to use problem. In conclusion, the cellulose composite waterproof film provided by the application has the advantages of controllable moisture permeability, larger moisture permeability, stronger mechanical property and higher hydrostatic pressure resistance.

Drawings

fig. 1 is a process flow diagram of the cellulose composite waterproof film of the present application.

Detailed Description

For a further understanding of the invention, reference will now be made to the preferred embodiments of the invention by way of example, and it is to be understood that the description is intended to further illustrate features and advantages of the invention, and not to limit the scope of the claims.

In view of the current situation of waterproof and moisture permeable films in the prior art, the application provides a cellulose-based cellulose composite waterproof film and a preparation method thereof. Specifically, the embodiment of the invention discloses a cellulose composite waterproof film, which is prepared from 70-100 parts by weight of cellulose pulp, 0-20 parts by weight of superfine functional material and 0-10 parts by weight of auxiliary agent;

the content of the superfine functional material is not 0, the superfine functional material is one or more of superfine functional powder and modified superfine functional powder, and the superfine functional powder is selected from one or more of silicon carbide superfine powder, silicon carbide aerogel, calcium carbonate superfine powder, carbon black superfine powder, carbon aerogel, silica superfine powder, silica aerogel, titanium dioxide superfine powder, titanium dioxide aerogel, talcum powder, mica powder, feldspar powder, barium sulfate superfine powder, wollastonite superfine powder, magnesium hydroxide superfine powder and micro-silicon superfine powder.

in the cellulose composite waterproof film provided herein, the cellulose pulp is selected from cellulose pulps well known to those skilled in the art, and the present application is not particularly limited, and the cellulose pulp is exemplified by one or more selected from cotton wool, wood pulp, paper pulp, straw, rice bran, sugar cane straw, hemp, and reed straw, and in specific embodiments, the cellulose pulp is selected from cotton wool. The cellulose contains abundant hydroxyl groups and can provide good moisture permeability. The content of the cellulose pulp is 70 to 100 parts by weight, in a specific embodiment, the content of the cellulose pulp is 78 to 99 parts by weight, and more specifically, the content of the cellulose pulp is 75 to 90 parts by weight.

in the cellulose composite waterproof film, the superfine functional material can change the molecular chain structure and the combination mode of cellulose, and can also improve the moisture permeability of the cellulose composite waterproof film. In the present application, the ultrafine functional material is one or more of an ultrafine functional powder and a modified ultrafine functional powder, that is, the ultrafine functional material may be an unmodified ultrafine functional powder, a modified ultrafine functional powder, an unmodified ultrafine functional powder, and a modified ultrafine functional powder. The modified superfine functional powder is modified by one or more of surface coating modification, surface chemical modification, mechanochemical modification and high-energy modification; wherein, the surface coating modification refers to the modification of the surface of the superfine powder by utilizing Van der Waals force between a coating material and the superfine powder or a physical method; the surface chemical modification refers to the surface modification of the ultrafine powder through the chemical reaction or chemical adsorption of a modifier and groups on the surface of the ultrafine powder; the mechanochemical modification refers to the improvement of the physical and chemical properties of the superfine powder by mechanical methods such as grinding, friction, crushing and the like, and the high-energy modification refers to the modification of the superfine powder by plasma or radiation treatment of the superfine powder.

specifically, the ultrafine functional powder is selected from one or more of silicon carbide ultrafine powder, silicon carbide aerogel, calcium carbonate ultrafine powder, carbon black ultrafine powder, carbon aerogel, silica ultrafine powder, silica aerogel, titanium dioxide ultrafine powder, titanium dioxide aerogel, talcum powder, mica powder, feldspar powder, barium sulfate ultrafine powder, wollastonite ultrafine powder, magnesium hydroxide ultrafine powder and micro-silicon ultrafine powder; in a specific embodiment, the ultrafine functional powder is selected from carbon black ultrafine powder, silica aerogel, barium sulfate ultrafine powder or talcum powder. The size of the superfine functional powder is 0.1-10 mu m; in a specific embodiment, the size of the ultrafine functional powder is 0.2 to 5 μm, and more specifically, the size of the ultrafine functional powder is 0.2 μm, 2 μm, 3 μm, or 5 μm. The content of the superfine functional material is 0-20 parts by weight and is not equal to 0; more specifically, the content of the ultrafine functional material is 1 to 10 parts by weight, and more specifically, the content of the ultrafine functional material is 1 to 5 parts by weight.

The cellulose composite waterproof film further comprises an auxiliary agent (i.e. mixture A), wherein the auxiliary agent is a common auxiliary agent well known to those skilled in the art, and specifically can be one or more selected from a defoaming agent, an antioxidant, a flame retardant, a mold release agent, a leveling agent, a light stabilizer, an antistatic agent, a mildew preventive and a crosslinking agent. The above-mentioned auxiliaries are specifically selected from materials well known to those skilled in the art, and the present application is not particularly limited thereto. The content of the auxiliary agent is 0-10 parts by weight, and in a specific embodiment, the content of the auxiliary agent is 1-5 parts by weight.

the application also provides a preparation method of the cellulose composite waterproof film, which specifically comprises the following steps as shown in figure 1:

A) Dissolving 70-100 parts by weight of cellulose pulp, 0-20 parts by weight of superfine functional material and 0-10 parts by weight of auxiliary agent in a solution, and stirring to obtain a cellulose solution;

B) defoaming the cellulose solution, and forming a film to obtain a cellulose initial film;

C) And (3) solidifying and exchanging the cellulose initial film in a solidifying bath, and drying to obtain the cellulose composite waterproof film.

the cellulose composite waterproof film prepared by the application does not have a porous structure, so that the phenomenon of micropore blockage can be avoided in use, and the problem of moisture permeability reduction in later-stage use is avoided.

In the specific preparation process, firstly, dissolving cellulose pulp, superfine functional materials and auxiliaries in a solvent according to the component ratio, and stirring to obtain a cellulose solution; in the process, the raw materials are mixed and preferably placed at the temperature of minus 5 ℃ to minus 50 ℃ for high-speed stirring until the cellulose is completely dissolved, and then the cellulose solution is obtained. The solution is an aqueous solution of an alkali solution and an amine, wherein the alkali solution is selected from one or more of a sodium oxide solution, a potassium hydroxide solution, a lithium hydroxide solution, an alkoxide solution, a lithium diisopropylamide solution, a proton sponge solution and a Schloth alkali solution, and the amine is selected from one or more of a methylamine solution, an ethylenediamine solution, a diisopropylamine solution, a triethanolamine solution, a tetrabutyl bromide solution, a urea solution, dimethylformamide and dimethylacetamide; in a particular embodiment, the solution is selected from a sodium hydroxide-urea solution. The cellulose can be fully dissolved by selecting the solution, the solution does not contain chemical medicines with strong toxicity, and the prepared product has small toxic residue and small environmental pollution.

After the cellulose solution is obtained, defoaming the cellulose solution, and forming a film to obtain a cellulose initial film; the above-mentioned defoaming and film forming are all technical means well known to those skilled in the art, and the application is not particularly limited, and the defoaming may be centrifugal defoaming or vacuum defoaming, and the film forming process may be selected from a coating process, a spin coating process or a casting process.

And finally, carrying out coagulation exchange on the obtained cellulose initial film in a coagulation bath, and drying to obtain the cellulose composite waterproof film. In the process, the cellulose initial film is preferably subjected to ion exchange and regeneration in a coagulating bath at the temperature of between 5 ℃ below zero and 99 ℃ to obtain the cellulose composite waterproof film. In this step, the cellulose solution is washed away from ions (ions in the alkali amine solution), thereby regenerating the cellulose. In the above process, the coagulation bath comprises water, N-dimethylformamide, dimethylacetamide, and 0.1-50.0 wt% of Na₂SO₄0.1-50.0 wt% (NH)₄)₂SO₄One or more of aqueous solution of (1) to (99.9) wt% of ethanol, aqueous solution of (0.1) to (99.9) wt% of methanol and aqueous solution of (0.1) to (50.0) wt% of glycerin; in particular toIn the examples, the coagulation bath is preferably carried out at 15 ℃ in a 90% ethanol aqueous solution.

After the preparation method is adopted, the thickness of the cellulose composite waterproof film prepared by the method is 0.01-0.05 mm, and the moisture permeability is more than 10000 g.m²/24h。

the invention can prepare the cellulose and cellulose composite material waterproof film with different moisture permeability performances and high moisture permeability by controlling the superfine powder with different proportions and different characteristics. Wherein, because the cellulose and cellulose composite material waterproof film with high moisture permeability does not have a porous structure, the phenomenon of micropore blockage can not occur in later use, thereby avoiding the problem of moisture permeability reduction in later use. Moreover, because the cellulose molecular chain contains a large amount of hydrophilic groups and the superfine powder adjusts the cellulose matrix structure, the excellent moisture permeability function, mechanical property and hydrostatic pressure resistance can be realized. Meanwhile, the technical scheme has the advantages of simple design process, simple process and easy realization of industrialization. Therefore, the cellulose and cellulose composite material waterproof moisture-permeable film prepared by the method has the advantages of controllable moisture permeability, larger moisture permeability, stronger mechanical property and higher hydrostatic pressure resistance.

For further understanding of the present invention, the cellulose composite waterproof film and the preparation method thereof provided by the present invention are described in detail below with reference to the following examples, and the scope of the present invention is not limited by the following examples.