Disclosure of Invention
The invention aims to overcome the defects that a large amount of oxidant harmful to the environment is used in the existing oxidant-induced polydopamine deposition method and the hydrophobic modification effect is poor, and provides a preparation method of a super-hydrophobic coating based on polydopamine self-assembly. The method can quickly form the super-hydrophobic coating on the surface of any material, and is a preparation method of the super-hydrophobic coating which is environment-friendly, quick, simple and convenient and has an extremely low rolling angle.
The invention adopts the following specific technical scheme:
the invention provides a preparation method of a super-hydrophobic coating based on polydopamine self-assembly, which comprises the following specific steps:
s1: dissolving dopamine hydrochloride and nano zero-valent iron in a tris (hydroxymethyl) aminomethane-hydrochloric acid buffer solution to obtain a mixed solution; the molar concentrations of dopamine hydrochloride and nano zero-valent iron in the mixed solution are both 1-50 mM;
s2: at room temperature, soaking a material to be coated in the mixed solution to ensure that the material to be coated is fully contacted with the mixed solution;
s3: taking out the material obtained after the dipping in the step S2, and cleaning and drying the material;
s4: and (4) soaking the material obtained in the step (S3) in a low surface energy modifier to enable the material and the low surface energy modifier to be in full contact, and after washing and drying, obtaining a super-hydrophobic coating based on polydopamine self-assembly on the surface of the material to be coated.
Preferably, the nano zero-valent iron is prepared by a liquid phase reduction method.
Preferably, in the step S2, the material to be coated is deposited in the mixed solution for 1-12 h while magnetic stirring is carried out, and the stirring speed is 100-500 r.min-1。
Preferably, in the step S3 and the step S4, the drying temperature is 50-120 ℃.
Preferably, the static water contact angle of the super-hydrophobic coating is 153.5-160.5 degrees, and the rolling angle is less than 1 degree.
Preferably, the low surface energy modifier is a mixed solution of methanol containing perfluorosilane and a tris-hydrochloric acid buffer solution, wherein in the low surface energy modifier, the volume fraction of the perfluorosilane is 0.1-5%, and the volume fraction of the tris-hydrochloric acid buffer solution is 5%; the perfluorosilane is preferably heptadecafluorodecyltrimethoxysilane or tridecafluorooctyltrimethoxysilane.
Preferably, the low surface energy modifier is an ethanol solution containing perfluoromercaptan, wherein the volume fraction of the perfluoromercaptan is 0.1-5%; the perfluorothiol is preferably perfluorodecyl thiol.
Preferably, the low surface energy modifier is an aqueous solution containing stearic acid, wherein the mass fraction of the stearic acid is 0.1%.
Preferably, the dipping time in the step S4 is 1 to 60 min.
Compared with the prior art, the invention has the following beneficial effects:
the method can be used for quickly constructing the super-hydrophobic coating on the surface of any material, the self-assembly speed of the obtained super-hydrophobic coating is extremely high, and the static water contact angle can reach 160.5 degrees after 1min of low surface energy modification; the obtained super-hydrophobic coating has an extremely low rolling angle (less than 1 degree), and has a large application potential in the fields of self-cleaning and marine antifouling. The super-hydrophobic coating prepared by the method has good chemical stability, can resist strong acid, weak base, salt and organic solvent, and has wide application prospect in the fields of composite material preparation, self-cleaning, oil-water separation, marine corrosion prevention, antifouling and the like.
Detailed Description
The invention will be further elucidated and described with reference to the drawings and the detailed description. The technical features of the embodiments of the present invention can be combined correspondingly without mutual conflict.
Example 1
The preparation method of the super-hydrophobic coating in the embodiment specifically comprises the following steps:
(1) and ultrasonically degreasing the glass slide in ethanol for 30min, washing the glass slide for 3 times by using deionized water, and then drying the glass slide in a blast oven at the temperature of 80 ℃ for 2h for later use.
(2) 6.057g of tris (hydroxymethyl) aminomethane is weighed in a beaker, dissolved by adding a proper amount of ultrapure water, transferred to a 1L volumetric flask, subjected to constant volume, and adjusted to pH 8.5 by using hydrochloric acid, thus obtaining tris (hydroxymethyl) aminomethane-hydrochloric acid buffer solution.
(3) Weighing 0.1g of dopamine hydrochloride and 0.014g of nano zero-valent iron in a 100mL beaker, adding 50mL of the tris-hydroxymethyl aminomethane-hydrochloric acid buffer solution prepared in the step (2), and magnetically stirring to fully dissolve the buffer solution to obtain a mixed solution.
(4) Immersing the glass slide in the mixed solution obtained in the step (3) for deposition for 4 hours while stirring with magnetic force at the stirring speed of 200 r-min-1And taking out the glass slide, washing the glass slide for 5 times by using deionized water, and drying the glass slide for 2 hours in a blast oven at the temperature of 80 ℃ for later use.
(5) Measuring 1mL of heptadecafluorodecyltrimethoxysilane, 18mL of methanol and 1mL of tris (hydroxymethyl) aminomethane-hydrochloric acid buffer solution in a 25mL beaker, and magnetically stirring for 12h to obtain the low surface energy modifier.
(6) And (3) soaking the glass slide obtained in the step (4) in the low surface energy modifier obtained in the step (5) for 1min, taking out the glass slide, washing the glass slide for 5 times by using deionized water, and drying the glass slide in a forced air oven at the temperature of 80 ℃ for 2h to prepare the super-hydrophobic coating on the surface of the glass slide.
The super-hydrophobic coating prepared in the example has a static water contact angle of 160.5 degrees and a rolling angle of less than 1 degree. As shown in fig. 1, which is an optical picture of the static water contact angle of the superhydrophobic coating obtained in this example, it can be seen from the figure that the water drops are spherical on the surface of the coating, and the water drops do not wet the surface of the coating.
Example 2
The preparation method of the super-hydrophobic coating in the embodiment specifically comprises the following steps:
(1) and ultrasonically degreasing the glass slide in ethanol for 30min, washing the glass slide for 3 times by using deionized water, and then drying the glass slide in a blast oven at the temperature of 80 ℃ for 2h for later use.
(2) 6.057g of tris (hydroxymethyl) aminomethane is weighed in a beaker, dissolved by adding a proper amount of ultrapure water, transferred to a 1L volumetric flask, subjected to constant volume, and adjusted to pH 8.5 by using hydrochloric acid, thus obtaining tris (hydroxymethyl) aminomethane-hydrochloric acid buffer solution.
(3) Weighing 0.1g of dopamine hydrochloride and 0.014g of nano zero-valent iron in a 100mL beaker, adding 50mL of the tris (hydroxymethyl) aminomethane-hydrochloric acid buffer solution prepared in the step (2), and magnetically stirring to fully dissolve the buffer solution to obtain a mixed solution.
(4) Immersing the glass slide in the mixed solution obtained in the step (3) for 1h, and simultaneously stirring by magnetic force at the stirring speed of 100 r.min-1And taking out the glass slide, washing the glass slide for 5 times by using deionized water, and drying the glass slide for 4 hours in a forced air oven at 50 ℃ for later use.
(5) Measuring 0.2mL of heptadecafluorodecyltrimethoxysilane, 18.8mL of methanol and 1mL of tris-hydroxymethyl aminomethane-hydrochloric acid buffer solution in a 25mL beaker, and magnetically stirring for 12h to obtain the low surface energy modifier.
(6) And (3) soaking the glass slide obtained in the step (4) in the low surface energy modifier obtained in the step (5) for 30min, taking out the glass slide, washing the glass slide for 5 times by using deionized water, and drying the glass slide in a forced air oven at the temperature of 80 ℃ for 2h to prepare the super-hydrophobic coating on the surface of the glass slide.
The super-hydrophobic coating prepared in the embodiment has a static water contact angle of 160.0 degrees and a rolling angle of less than 1 degree.
Example 3
The preparation method of the super-hydrophobic coating in the embodiment specifically comprises the following steps:
(1) and ultrasonically degreasing the glass slide in ethanol for 30min, washing the glass slide for 3 times by using deionized water, and then drying the glass slide in a blast oven at the temperature of 80 ℃ for 2h for later use.
(2) 6.057g of tris (hydroxymethyl) aminomethane is weighed in a beaker, dissolved by adding a proper amount of ultrapure water, transferred to a 1L volumetric flask, subjected to constant volume, and adjusted to pH 8.5 by using hydrochloric acid, thus obtaining tris (hydroxymethyl) aminomethane-hydrochloric acid buffer solution.
(3) Weighing 0.1g of dopamine hydrochloride and 0.014g of nano zero-valent iron in a 100mL beaker, adding 50mL of the tris (hydroxymethyl) aminomethane-hydrochloric acid buffer solution prepared in the step (2), and magnetically stirring to fully dissolve the buffer solution to obtain a mixed solution.
(4) Immersing the glass slide in the mixed solution obtained in the step (3) for deposition for 4 hours while stirring with magnetic force, wherein the stirring speed is 180 r.min-1And taking out the glass slide, washing the glass slide for 5 times by using deionized water, and drying the glass slide for 1 hour in a blast oven at the temperature of 120 ℃ for later use.
(5) Measuring 0.1mL of heptadecafluorodecyltrimethoxysilane, 18.9mL of methanol and 1mL of tris-hydroxymethyl aminomethane-hydrochloric acid buffer solution in a 25mL beaker, and magnetically stirring for 12h to obtain the low surface energy modifier.
(6) And (3) soaking the glass slide obtained in the step (4) in the low surface energy modifier obtained in the step (5) for 10min, taking out the glass slide, washing the glass slide for 5 times by using deionized water, and drying the glass slide in a blast oven at the temperature of 80 ℃ for 2h to prepare the super-hydrophobic coating on the surface of the glass slide.
The super-hydrophobic coating prepared in the example has a static water contact angle of 157.2 degrees and a rolling angle of less than 1 degree.
Example 4
The preparation method of the super-hydrophobic coating in the embodiment specifically comprises the following steps:
(1) and ultrasonically degreasing the glass slide in ethanol for 30min, washing the glass slide for 3 times by using deionized water, and then drying the glass slide in a blast oven at the temperature of 80 ℃ for 2h for later use.
(2) 6.057g of tris (hydroxymethyl) aminomethane is weighed in a beaker, dissolved by adding a proper amount of ultrapure water, transferred to a 1L volumetric flask, subjected to constant volume, and adjusted to pH 8.5 by using hydrochloric acid, thus obtaining tris (hydroxymethyl) aminomethane-hydrochloric acid buffer solution.
(3) Weighing 0.1g of dopamine hydrochloride and 0.014g of nano zero-valent iron in a 100mL beaker, adding 50mL of the tris (hydroxymethyl) aminomethane-hydrochloric acid buffer solution prepared in the step (2), and magnetically stirring to fully dissolve the buffer solution to obtain a mixed solution.
(4) Immersing the slide in the step(3) The obtained mixed solution is deposited for 12h while being stirred by magnetic force, and the stirring speed is 350 r.min-1And taking out the glass slide, washing the glass slide for 5 times by using deionized water, and drying the glass slide for 2 hours in a blast oven at the temperature of 80 ℃ for later use.
(5) 0.2mL of perfluorodecyl mercaptan and 19.8mL of ethanol are weighed into a 25mL beaker and magnetically stirred for 12h to obtain the low surface energy modifier.
(6) And (3) soaking the glass slide obtained in the step (4) in the low surface energy modifier obtained in the step (5) for 60min, taking out the glass slide, washing the glass slide for 5 times by using deionized water, and drying the glass slide in a 50 ℃ blast oven for 4h to prepare the super-hydrophobic coating on the surface of the glass slide.
The super-hydrophobic coating prepared in the embodiment has a static water contact angle of 153.5 degrees and a rolling angle of less than 10 degrees.
Example 5
The preparation method of the super-hydrophobic coating in the embodiment specifically comprises the following steps:
(1) and ultrasonically degreasing the glass slide in ethanol for 30min, washing the glass slide for 3 times by using deionized water, and then drying the glass slide in a blast oven at the temperature of 80 ℃ for 2h for later use.
(2) 6.057g of tris (hydroxymethyl) aminomethane is weighed in a beaker, dissolved by adding a proper amount of ultrapure water, transferred to a 1L volumetric flask, subjected to constant volume, and adjusted to pH 8.5 by using hydrochloric acid, thus obtaining tris (hydroxymethyl) aminomethane-hydrochloric acid buffer solution.
(3) Weighing 0.1g of dopamine hydrochloride and 0.014g of nano zero-valent iron in a 100mL beaker, adding 50mL of the tris (hydroxymethyl) aminomethane-hydrochloric acid buffer solution prepared in the step (2), and magnetically stirring to fully dissolve the buffer solution to obtain a mixed solution.
(4) Immersing the glass slide in the mixed solution obtained in the step (3) for deposition for 6 hours while stirring with magnetic force at the stirring speed of 500 r-min-1And taking out the glass slide, washing the glass slide for 5 times by using deionized water, and drying the glass slide for 2 hours in a blast oven at the temperature of 80 ℃ for later use.
(5) 0.02g of stearic acid was weighed and 19.98mL of ultrapure water was weighed into a 25mL beaker, and magnetically stirred at 85 ℃ for 1h to obtain a low surface energy modifier.
(6) And (3) soaking the glass slide obtained in the step (4) in the low surface energy modifier obtained in the step (5) for 1min, taking out the glass slide, washing the glass slide for 5 times by using deionized water, and drying the glass slide in a 75 ℃ blast oven for 2h to prepare the super-hydrophobic coating on the surface of the glass slide.
The super-hydrophobic coating prepared in the embodiment has a static water contact angle of 160.2 degrees and a rolling angle of less than 1 degree.
Example 6
The preparation method of the super-hydrophobic coating in the embodiment specifically comprises the following steps:
(1) and ultrasonically degreasing the glass slide in ethanol for 30min, washing the glass slide for 3 times by using deionized water, and then drying the glass slide in a blast oven at the temperature of 80 ℃ for 2h for later use.
(2) 6.057g of tris (hydroxymethyl) aminomethane is weighed in a beaker, dissolved by adding a proper amount of ultrapure water, transferred to a 1L volumetric flask, subjected to constant volume, and adjusted to pH 8.5 by using hydrochloric acid, thus obtaining tris (hydroxymethyl) aminomethane-hydrochloric acid buffer solution.
(3) 0.1g of dopamine hydrochloride and 0.014g of nano zero-valent iron were weighed in a 100mL beaker, and 50mL of the tris-hydroxymethyl aminomethane-hydrochloric acid buffer solution prepared in step (2) was added to obtain a mixed solution.
(4) Immersing the glass slide in the mixed solution obtained in the step (3) for deposition for 6 hours while stirring with magnetic force, wherein the stirring speed is 400 r.min-1And taking out the glass slide, washing the glass slide for 5 times by using deionized water, and drying the glass slide for 2 hours in a blast oven at the temperature of 40 ℃ for later use.
(5) 0.2mL of tridecafluorooctyltrimethoxysilane, 18.9mL of methanol and 1mL of tris (hydroxymethyl) aminomethane-hydrochloric acid buffer solution are weighed into a 25mL beaker and stirred magnetically for 12h to obtain the low surface energy modifier.
(6) And (3) soaking the glass slide obtained in the step (4) in the low surface energy modifier obtained in the step (5) for 10min, taking out the glass slide, washing the glass slide for 5 times by using deionized water, and drying the glass slide in a blast oven at 40 ℃ for 2h to prepare the super-hydrophobic coating on the surface of the glass slide.
The super-hydrophobic coating prepared in the example has a static water contact angle of 158.3 degrees and a rolling angle of less than 1 degree.
The above-described embodiments are merely preferred embodiments of the present invention, which should not be construed as limiting the invention. Various changes and modifications may be made by one of ordinary skill in the pertinent art without departing from the spirit and scope of the present invention. Therefore, the technical scheme obtained by adopting the mode of equivalent replacement or equivalent transformation is within the protection scope of the invention.