阅读说明：本技术 一种人造超润湿荷叶状Janus薄膜的制备 (Preparation of artificial super-wetting lotus-shaped Janus film ) 是由 沈华杰 杨玉山 王秋华 唐艺秦 邱坚 于 2019-04-07 设计创作，主要内容包括：本发明涉及一种人造超润湿荷叶状Janus薄膜的制备,特别涉及一种具有超润湿性表面的仿生荷叶表面微结构超润湿薄膜。方法：采用软印刷技术,经过两次复形和转录后,在固化的PDMS弹性体表面进行仿生精细修饰,制备了与荷叶微纳米结构相类似的超润湿Janus薄膜。本发明在PDMS弹性体表面仿生构建超润湿表面,仿生人造荷叶状表面的超润湿特性,作为制备的Janus薄膜具有纳米类荷叶状的超亲水表面和十二烷醇修饰的超疏水。Janus薄膜的超疏水和超亲水侧的水接触角分别大于150°和<5°,表明在一个PDMS弹性体上制备了Janus润湿性。(The invention relates to preparation of an artificial super-wetting lotus leaf-shaped Janus film, in particular to a bionic lotus leaf surface microstructure super-wetting film with a super-wetting surface. The method comprises the following steps: adopting a soft printing technology, performing bionic fine modification on the surface of the cured PDMS elastomer after twice reshaping and transcription, and preparing the super-wetting Janus film similar to the lotus leaf micro-nano structure. The invention bionically constructs a super-wetting surface on the surface of a PDMS elastomer, bionically simulates the super-wetting characteristic of an artificial lotus-shaped surface, and the Janus film prepared by the method has a nano lotus-like super-hydrophilic surface and super-hydrophobicity modified by dodecanol. The water contact angles of the superhydrophobic and superhydrophilic sides of the Janus film were greater than 150 ° and <5 °, respectively, indicating that Janus wettability was prepared on one PDMS elastomer.)

1. Preparation of an artificial super-wetting lotus-shaped Janus film, which is characterized by comprising the following steps: the method specifically comprises the following steps:

(1) PDMS mixed liquid, the volume ratio of the main agent PDMS to the curing agent is 10:1;

(2) pouring the mixture obtained in the step (1) onto the surface of a silicon wafer, degassing for a certain time, curing for a certain time at a certain temperature, stripping the PDMS elastomer from the surface of the Si wafer, curing for 24 hours, and cutting into squares;

(3) preparing a PVB mixed solution;

(4) putting clean fresh lotus leaves in a culture dish, pouring the mixed liquid in the step (1), drying and curing to obtain a PDMS template;

(5) coating the mixture in the step (3) on the surface of the PDMS elastic body, performing secondary reshaping by using the template in the step (4), curing at a certain temperature, and stripping the template to obtain the super-wetting material with the lotus leaf-shaped surface structure.

2. The preparation of an artificial super-wetting lotus-shaped Janus film according to claim 1, wherein: the curing agent in the step (1) is 184-silicon rubber.

3. The preparation of an artificial super-wetting lotus-shaped Janus film according to claim 1, wherein: the certain time in the step (2) is 0-2h, preferably 1 h;

the temperature is 50-70 ℃, preferably 60 ℃.

4. The preparation of an artificial super-wetting lotus-shaped Janus film according to claim 1, wherein: the mixed solution in the step (3) is prepared from PVB, absolute ethyl alcohol, OTS, ethyl orthosilicate, ammonium persulfate, TMOTS and PDMS.

5. The preparation of an artificial super-wetting lotus-shaped Janus film according to claim 1, wherein: the drying and curing temperature in the step (4) is 60 ℃, the time is 1-5h, and the thickness is 2-5 mm.

6. The preparation of an artificial super-wetting lotus-shaped Janus film according to claim 1, wherein: the curing temperature in the step (5) is 60-90 ℃ and the time is 1-24 h.

Technical Field

The invention belongs to the technical field of super-wetting interfaces, and particularly relates to preparation of an artificial super-wetting lotus-shaped Janus film.

Background

Wood is the most valuable property that nature imparts to humans. The wood has various varieties and different functions, and the wood has wide application due to the natural characteristics of the wood. The wood is mainly used in two fields of engineering and industry, including buildings, military industry, vehicles and ships, textiles, artificial boards, industrial and agricultural tools, furniture, musical instruments, sports equipment, wood products, sleepers, bridges, wharf river bank piles and the like. The wood is a porous and anisotropic natural organic macromolecular compound, is easy to decay and damage by worms, is often damaged by marine drilling animals when being used as coastal building materials or wooden ships, is easy to burn, causes a plurality of inevitable natural defects such as fire and the like, has great influence on the corrosion performance of the wood by moisture, so that the surface of the wood is modified and treated, the hydrophobicity of the wood is enhanced, the reasonable utilization, the efficient utilization and the sustainable development of wood resources are realized, and the life quality of human beings is continuously improved.

Surface wettability is a property of a material surface that depends primarily on surface energy and surface structure. Many studies report that the combination of roughness and low surface energy materials results in surface properties. Many biological surface structures in nature have evolved over billions of years. Furthermore, the evolutionary process confers a number of functional plant surfaces with unusual properties, such as self-cleaning and low adhesion. The best known example is the super wetting of the lotus leaf surface. It is reported that the surfaces of lotus leaves are all covered with a high purity wax with a relatively coarse particle size under normal temperature conditions, so that the lotus leaves have a water contact angle of more than 150 DEG and a sliding angle of less than 10 DEG, and show super-wettability and self-cleaning effects.

Inspired by the leaf-loading effect, studies have been conducted in recent years on low and high surface energy surfaces, and rapid progress has been made. Therefore, it can move the surface of the wood from the hydrophilic surface to the hydrophobic surface, thereby effectively preventing the invasion and destruction of moisture. The key of the surface is the rough surface appearance and low surface chemical energy just like a lotus surface. The synthesis method comprises the following steps: solution method, sol-gel method, coagulation method, plasma method, and the like. However, at present, the relevant domestic super-wetting material research experiment conditions are harsh, the development process is extremely complex, the steps are complex, the cost is high, and the method is not suitable for mass production or industrial survival. According to the inspired self-cleaning and super-wetting structure of the lotus leaf, the provincial-imitated artificial super-wetting lotus-shaped Janus film is prepared by a simple and easy template imprinting modification method.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides the preparation of the artificial super-wetting lotus-shaped Janus film, and the super-wetting performance of the Janus film can be realized.

The invention provides a preparation method of an artificial super-wetting lotus-shaped Janus film, which is characterized by comprising the following steps of: the method specifically comprises the following steps:

(1) PDMS mixed liquid, the volume ratio of the main agent PDMS to the curing agent is 10:1;

(2) pouring the mixture obtained in the step (1) onto the surface of a silicon wafer, degassing for a certain time, curing for a certain time at a certain temperature, stripping the PDMS elastomer from the surface of the Si wafer, curing for 24 hours, and cutting into squares;

(3) preparing a PVB mixed solution;

(4) putting clean fresh lotus leaves in a culture dish, pouring the mixed liquid in the step (1), drying and curing to obtain a PDMS template;

(5) coating the mixture in the step (3) on the surface of the PDMS elastic body, performing secondary reshaping by using the template in the step (4), curing at a certain temperature, and stripping the template to obtain the super-wetting material with the lotus leaf-shaped surface structure.

In the preparation of the artificial super-wetting lotus-shaped Janus film, the curing agent in the step (1) is preferably 184-silicone rubber.

Preferably, the certain time in the step (2) is 1 hour; the certain temperature is 60 ℃.

In the preparation of the artificial super-wetting lotus-shaped Janus film, preferably, the mixed solution in the step (3) is prepared from PVB, absolute ethyl alcohol, OTS, ethyl orthosilicate, ammonium persulfate, TMOTS and PDMS.

In the preparation of the artificial super-wetting lotus-shaped Janus film, preferably, the drying and curing temperature in the step (4) is 60 ℃, the time is 2 hours, and the thickness is 3 mm.

In the preparation of the artificial super-wetting lotus-shaped Janus film, the curing temperature in the step (5) is preferably 70 ℃ and the curing time is 12 hours.

The invention has the advantages that:

1. the invention provides a preparation method of an artificial super-wetting lotus-shaped Janus film, wherein the prepared artificial super-wetting lotus-shaped Janus film has a super-wetting characteristic, the contact angle of a super-hydrophobic side exceeds 155 degrees, and the contact angle of a super-hydrophilic side is only 5 degrees; meanwhile, the lotus leaf has the self-cleaning effect;

2. the invention provides a preparation method of an artificial super-wetting lotus-shaped Janus film, and the temperature in the preparation process is low and easy to control;

3. the invention provides a preparation method of an artificial super-wetting lotus-shaped Janus film, which does not need high-precision precise instruments and equipment.

Drawings

In order to more clearly illustrate the detailed description of the invention or the technical solutions in the prior art, the drawings that are needed in the detailed description of the invention or the prior art will be briefly described below. Throughout the drawings, like elements or portions are generally identified by like reference numerals. In the drawings, elements or portions are not necessarily drawn to scale.

FIG. 1: an electron microscope image of the surface of the PDMS template prepared in the present invention was taken.

FIG. 2: the surface electron microscope image of the artificial super-wetting lotus-shaped Janus film surface obtained by the method is adopted.

FIG. 3: the artificial super-wetting lotus-shaped Janus film obtained by the method has super-oleophylic property on the surface.

FIG. 4: the artificial super-wetting lotus-shaped Janus film obtained by the method has the super-hydrophobic characteristic on the surface.

Detailed description of the preferred embodiments

The preparation of an artificial super-wetting lotus-shaped Janus film of the invention is specifically described below by combining the drawings and the embodiment.

The invention provides a preparation method of an artificial super-wetting lotus-shaped Janus film, which specifically comprises the following steps:

(1) PDMS mixed liquid, the volume ratio of the main agent PDMS to the curing agent is 10:1;

(2) pouring the mixture obtained in the step (1) onto the surface of a silicon wafer, degassing for a certain time, curing for a certain time at a certain temperature, stripping the PDMS elastomer from the surface of the Si wafer, curing for 24 hours, and cutting into squares;

(3) preparing a PVB mixed solution;

(4) putting clean fresh lotus leaves in a culture dish, pouring the mixed liquid in the step (1), drying and curing to obtain a PDMS template;

(5) coating the mixture in the step (3) on the surface of the PDMS elastic body, performing secondary reshaping by using the template in the step (4), curing at a certain temperature, and stripping the template to obtain the super-wetting material with the lotus leaf-shaped surface structure.

In the preparation of the artificial super-wetting lotus-shaped Janus film, the curing agent in the step (1) is preferably 184-silicone rubber.

Preferably, the certain time in the step (2) is 1 hour; the certain temperature is 60 ℃.

In the preparation of the artificial super-wetting lotus-shaped Janus film, preferably, the mixed solution in the step (3) is prepared from PVB, absolute ethyl alcohol, OTS, ethyl orthosilicate, ammonium persulfate, TMOTS and PDMS.

In the preparation of the artificial super-wetting lotus-shaped Janus film, preferably, the drying and curing temperature in the step (4) is 60 ℃, the time is 2 hours, and the thickness is 3 mm.

In the preparation of the artificial super-wetting lotus-shaped Janus film, the curing temperature in the step (5) is preferably 70 ℃ and the curing time is 12 hours.

The invention provides a preparation method of an artificial super-wetting lotus-shaped Janus film, which can be widely applied to the technical field of super-wetting interfaces.

The microscopic morphologies of the PDMS template and the biomimetic super-wet wood surface prepared in this example were analyzed by Scanning Electron Microscope (SEM). The super-wet wood has uniform surface, clear and visible micro-nano mastoid with the size of about 10 microns, and is filled and covered on the surface of the wood. The shape of the static water drop on the super-wetting wood surface is close to a sphere, the contact angle of the static water is about 157.5 degrees +/-0.5 degrees, and the rolling angle is 6 degrees.