Soft plasma polymerization process for a mechanically durable superhydrophobic nanostructured coating

The present invention relates to the art of atmospheric or reduced pressure plasma polymerization methods for depositing superhydrophobic coatings.

A surface with high water repellency is called superhydrophobic. Some species, such as mosquito eyes, water striders, and lotus leaves, have surfaces with superhydrophobic properties.

Kumar et al., Plasma Processes and Polymers, Vol. 7, pp. 926-938 (2010), low surface energy coating of 1H, 1H, 2H, 2H-perfluorodecyl acrylate (PFDA) by plasma accelerated chemical vapor deposition in low pressure induced excitation high frequency plasma. The preparation of is disclosed. Gupta et al., Langmuir, Vol. 22 (No. 24), pp. 1007410052 (2006) disclose the preparation of low surface energy poly-PFDA coatings by initiated chemical vapor deposition. Anthony et al., Chemistry of Materials, Vol. 21, pp. 4401-4403 (2009), disclose the preparation of low surface energy coatings by corona discharge using 1H, 1H, 2H, 2H-heptadecafluorodecyl acrylates. Unfortunately, the water contact angles of these coatings are fairly low, i.e. about 120 °. It is assumed that this low water contact angle is caused by the low roughness of these deposition methods.

WO2013 / 113875 is to produce a hyperassertive coating on a substrate, using a dielectric barrier discharge to generate a plasma in the processing space under atmospheric pressure; and a fluoro-acrylate monomer, fluoro- A method is disclosed comprising introducing into the plasma a coating forming material selected from the group consisting of alkyl acrylate monomers, fluoro-methacrylate monomers, fluoro-alkyl methacrylate monomers, fluoro-silane monomers or combinations thereof.

U.S. Patent Application Publication No. 2004/0022945 discloses a method of forming a coating on a substrate using atmospheric pressure plasma discharge. This method introduces an atomized liquid and / or solid coating forming material into an atmospheric pressure plasma discharge and / or an ionized gas stream resulting from it, and exposes the substrate to the atomized coating forming material. Including. This document also describes methods for polymerizing polymer-forming materials and devices for forming coatings on substrates.

U.S. Patent Application Publication No. 2007/0202270 discloses methods and equipment for coating substrates with inorganic-organic hybrid polymer materials. In this method, plasma is generated and maintained according to dielectric barrier discharge techniques. This method includes a step of introducing a sample into the space between two electrodes, a step of generating a plasma discharge between the electrodes, and a step of mixing an aerosol containing a hybrid organic / inorganic crosslinked prepolymer with the plasma discharge. ..

U.S. Patent Application Publication No. 2009/0065485 is a method of plasma treating the surface to generate non-equilibrium atmospheric pressure plasma in a dielectric housing having an inlet and an outlet through which process gas flows from the inlet to the outlet. , The method is disclosed.

In US Patent Application Publication No. 2014/0042130, a process gas, usually containing helium, is injected through the inlet while applying radio frequency high voltage to at least one electrode located within a dielectric housing with inlet and outlet. Disclosed are methods of plasma treating a substrate, including passing through an electrode and flowing to an outlet, thereby generating a non-equilibrium atmospheric pressure plasma. An atomized or gaseous surface treatment agent is incorporated into the non-equilibrium atmospheric pressure plasma. The substrate is placed adjacent to the plasma outlet so that the surface is in contact with the plasma and moves relative to the plasma outlet.

WO2016 / 198857A1 teaches a protective crosslinked polymer coating for substrates that can be obtained by exposing the substrate to plasma containing monomeric compounds and crosslinking reagents. In this document, in one example, it is obtained from a cross-linking reagent from the list containing 1H, 1H, 2H, 2H-perfluorooctyl acrylate monomer compounds and, among other examples, 1,3-divinyltetramethyldisiloxane (DVTMDS). The coating to be used is disclosed.

WO2003 / 086030A1 teaches how to form a coating on a powder substrate. This document discloses that a siloxane organic copolymer can be formed on the surface of a powder substrate using a mixture of an organic monomer and a silicon-containing monomer. This document discloses a first list of organic coating forming materials, including fluoroalkyl (meth) acrylates, among other examples. In this document, silanes (eg, silanes, alkylsilanes, alkylhalosilanes, alkoxysilanes), and organically functional linear and cyclic siloxanes (eg, Si-H-containing, halo-functional, and haloalkyl-functional). Linear siloxanes (eg, polydimethylsiloxanes) and cyclic siloxanes (eg, octamethylcyclotetrasiloxanes), including linear and cyclic siloxanes (eg, tetramethylcyclotetrasiloxane and tri (nonofluorobutyl) trimethylcyclotrisiloxane). A second list of silicon-containing materials, including), is further disclosed. In this document, in one example, a coating on rice husk ash obtained from tetramethylcyclotetrasiloxane is disclosed.

<p> The water contact angle of the coating presented above is usually quite low. In addition to the hydrophobicity of the coating, durability and mechanical resistance are also important, especially the combination of high resistance to the abrasive constraint of the coating and high elasticity. The above literature does not disclose the means by which a particular coating composition or a single process achieves all of these properties.</p><p> There is still a need for improved hyperhydrophobic coatings and methods of deposition thereof in the art.</p><p> An object of the present invention is to solve at least a part of the above-mentioned problems.</p>

<p> Outline of the Invention In the first aspect, the present invention provides the method of depositing a coating on a substrate according to claim 1.</p><p> In a second aspect, the invention provides the substrate coating according to claim 14.</p>

<p> The present invention is beneficial because it provides a mechanically durable superhydrophobic coating. The coating comprises a nano-order domain that connects the hard regions with the sections of the soft lattice. The nano-order domains are homogeneously dispersed and randomly oriented. The coating has high resistance to polishing restraint as well as high elasticity.</p>

<figref num="1">It is a figure which shows the schematic of the dielectric barrier discharge system for soft plasma polymerization of the 1st and 2nd precursors by a preferable embodiment of this invention.</figref><figref num="2">It is a figure which shows the schematic of the coating by the prior art formed by the method which the 1st and 2nd precursors are injected alternately into a processing area.</figref><figref num="3">It is a figure which shows the schematic of the coating by this invention which comprises a nano-order domain which connects a high hardness region and a section of a soft lattice.</figref><figref num="4">It is a figure which shows the schematic diagram of the 1H, 1H, 2H, 2H-perfluorodecyl acrylate (PFDA) monomer.</figref><figref num="5">It is a figure which shows the schematic diagram of 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane (V4D4) monomer.</figref><figref num="6">It is a figure which shows the MALDI mass spectrum performed with the early V4D4 plasma polymer.</figref><figref num="7">It is a figure which shows the MALDI mass spectrum performed with the early PFDA plasma polymer.</figref><figref num="8">It is a figure which shows the comparison of the MALDI mass spectrum of the multilayer structure including the alternating layer (see FIG. 2) and the coating by this invention (see FIG. 3).</figref><figref num="9">It is a graph which shows the change of elastic modulus of a coating by this invention as a function of a monomer content.</figref>

Detailed Description of the Invention The present invention relates to a method of depositing a coating on a substrate and the resulting substrate coating. The invention is summarized in the corresponding section above. Hereinafter, the present invention will be described in detail, preferred embodiments will be described, and the present invention will be illustrated by examples.

Unless otherwise defined, all terms used in the disclosure of the present invention, including technical and scientific terms, have meaning generally understood by those skilled in the art to which the present invention belongs. Further guidance includes definitions of terms to better understand the teachings of the present invention.

The following terms as used herein have the following meanings: as used herein, "one (a)", "one (an)", and "that (the)" Referents to both singular and plural referents, unless explicitly indicated by the context. As an example, "(one) parcel" refers to one or more parcels.

As used herein to refer to measurable values such as parameters, quantities, durations, etc., "about" means +/- 20% or less, preferably +/- 10% or less of the specified values and of the specified values. , More preferably +/- 5% or less, even more preferably +/- 1% or less, even more preferably +/- 0.1% or less, and any such variation. Appropriate to carry out in the disclosed invention. However, it should be understood that the value itself referred to by the modifier "about" is also specifically disclosed.

As used herein, "Comprise," "comprising," and "comprises," and "comprised of" are "include," "including." ) , Includes or contains , contains , contains , which is synonymous with the following, for example, inclusion that clearly indicates the existence of a component. A subject or open-ended term that does not preclude or exclude the existence of further undescribed components, features, elements, components, or processes known in the art or disclosed herein. ..

The description of a numeric range by endpoints includes all numeric and fractional parts contained within that range, as well as the endpoints described.

Here and throughout the specification, the expressions "% by weight", "percent weight", "% wt" or "wt%" are used relative to the total weight of the formulation, unless otherwise defined. Refers to the relative weight of the ingredients.

As used herein, the term "standard liter per minute" (slm) is a unit of volumetric flow rate of gas corrected to standard conditions for temperature and absolute pressure. These standard conditions include 0 degrees Celsius and 1 bar as reference points.

In a first aspect, the invention relates to a method of depositing a coating on a substrate. A first precursor containing a fluoro-acrylate monomer, a fluoro-alkyl acrylate monomer, a fluoro-methacrylate monomer, a fluoro-alkyl methacrylate monomer, a fluoro-silane monomer, or a combination or derivative thereof is prepared. A second precursor containing a linear siloxane, a silane monomer, a cyclosiloxane, a cyclosilane monomer, or a combination or derivative thereof is prepared. In this method, the first and second precursors are simultaneously injected into the treatment region, and the first and second and second and second precursors are simultaneously injected onto the substrate by creating an atmospheric pressure or reduced pressure plasma discharge in the treatment region. It comprises depositing a coating derived from the second precursor. The substrate is at least partially inserted therein in the treated area.

In the second aspect, the present invention relates to a substrate coating obtained according to the first aspect of the present invention. Substrate coatings include alternating multi-stack nanostructures. The base material coating is formed by copolymerization of the first precursor and the second precursor. Preferably, the alternating multi-stack nanostructures of the substrate coating are essentially randomly oriented and essentially homogeneous in terms of dispersion.

The present invention is beneficial because it provides a mechanically durable superhydrophobic coating. The coating comprises a nano-order domain that connects the hard regions with the sections of the soft lattice. The nano-order domains are preferably uniformly dispersed and randomly oriented. This results in a coating that is highly resistant to polishing restraints and highly elastic. Moreover, this is achieved by a single deposition process.

The coating is made on all or part of the surface of the substrate by copolymerizing the first and second precursors using atmospheric or reduced pressure discharge, preferably atmospheric pressure discharge. The plasma may be generated continuously or in a pulse mode containing one or more cycles including a period during which the plasma is generated and a period during which the plasma is not generated. The substrate is placed in the treated area, after which the coating is deposited on the surface of the substrate.

FIG. 1 shows a schematic representation of a dielectric barrier discharge (DBD) system that can be used in the method according to the first aspect of the invention in a preferred embodiment. In this embodiment, the plasma discharge is a dielectric barrier discharge in which an AC voltage is applied over the processing region. The system comprises a first set of electrodes (9) and a second set of electrodes (10). Each set of electrodes includes at least one electrode, eg, one, two, three, four, or more. The two sets of electrodes are separated by at least one insulating dielectric barrier (12). Preferably, the dielectric barrier is located essentially adjacent to the top set of electrodes (9). Optionally, a dielectric barrier can be placed essentially adjacent to the lower set of electrodes (10). Thereby, the two sets of electrodes can define a treatment area (8) or treatment gap in which a substrate can be prepared for treatment. In other words, two sets of electrodes are placed on opposite sides of the processing area. The substrate inserted into the treatment area (8) may also provide a dielectric barrier if the substrate material is capable of doing so. Preferably, the height of the treated area, i.e. the gap defined by the electrodes, is at least about 0.1 mm and up to about 10 mm, eg, about 0.1 mm, about 0.125 mm, about 0.16 mm, about 0.2 mm, about 0.25, about. 0.315mm, about 0.4mm, about 0.5mm, about 0.63mm, about 0.795mm, about 1mm, about 1.26mm, about 1.58mm, about 2mm, about 2.5mm, about 3.16mm, about 3.98mm, about 5mm, about 6.31 mm, about 7.94 mm, about 10 mm, or any value in between. More preferably, the processing area is at least about 0. It comprises a gap of 2 mm and up to about 5 mm, even more preferably a gap of at least about 1 mm and up to about 4 mm, for example a gap of about 2 mm. The dielectric barrier (12) material preferably comprises glass, quartz, ceramic, or polymer. Preferably, the dielectric barrier (12) material has low dielectric loss and high absolute breakdown strength. Preferably, the electrode material comprises aluminum.

In FIG. 1, the system is schematically represented in cross section and has two sets of electrodes (9, 10) in a plane-plane or parallel plate configuration. However, various reactor configurations are possible. One or both of the electrodes may be, for example, cylindrical such that the two sets of electrodes are in a coaxial configuration, may have a wire plane configuration, or may have a point plane configuration.

The system of FIG. 1 further comprises a power supply (11) for supplying high voltage alternating current (AC voltage; alternating current voltage) across two sets of electrodes (9, 10). Therefore, the system is configured to supply an AC voltage over the processing area. The electrode (10) of the lower set is preferably grounded, and the power supply (11) for supplying the AC voltage is preferably connected to the electrode (9) of the upper set. The power density across the two sets of electrodes, i.e. the power density of the plasma discharge, is preferably at least 0.05 W.cm.^-2Is. The power density across the two sets of electrodes, i.e. the power density of the plasma discharge, is preferably up to 100 W. cm.^-2, More preferably up to 50W.cm^-2, Even more preferably up to 20W.cm^-2, Even more preferably up to 10W.cm^-2, Most preferably up to 5W.cm^-2Is. Preferably, the AC voltage has an amplitude of up to 50 kV, more preferably an amplitude of at least 1 kV and up to 20 kV, eg, about 1 kV, about 1.26 kV, about 1.58 kV, about 2 kV, about 2.5 kV, about 3.16 kV. Includes amplitudes of about 3.98kV, about 5kV, about 6.31kV, about 7.94kV, about 10kV, about 12.6kV, about 15.8kV, about 20kV, or any value in between. Preferably, the AC voltage has frequencies of at least 500 Hz and up to 100 kHz, such as about 500 Hz, about 631 Hz, about 794 Hz, about 1 kHz, about 1.26 kHz, about 1.58 kHz, about 2 kHz, about 2.5 kHz, about 3.16 kHz, About 3.98kHz, about 5kHz, about 6.31kHz, about 7.94kHz, about 10kHz, about 12.6kHz, about 15.8kHz, about 20kHz, about 25kHz, about 31.6kHz, about 39.8kHz, about 50kHz, about 63.1kHz, about 79.4kHz Includes frequencies of about 100 kHz, or any value in between. More preferably, the AC voltage has a frequency of at least 500 Hz and up to 4.5 kHz, even more preferably at least 750 Hz and up to 3 kHz, and even more preferably at least 1 kHz and up to 2.25 kHz, for example about 1 kHz. Includes frequencies of about 1.25kHz, about 1.5kHz, about 1.75kHz, about 2kHz, or about 2.25kHz. Most preferably, the AC voltage comprises a frequency of about 1.5 kHz. These numerical specifications allow for so-called soft plasma conditions or so-called soft plasma polymerization regimes, i.e., controlled polymerization in which the polymerization sites are selectively activated, while the first and second precursors. Plasma process conditions that maintain the other chemical functions of the monomer.

In a preferred embodiment, the plasma generated by the dielectric barrier discharge is cold plasma, i.e., the plasma temperature or adjacent surface temperature is less than 100 ° C. Preferably, the discharge is carried out at room temperature.

In the dielectric barrier system shown in FIG. 1, plasma gas can be inserted (1) from the inlet of the processing region (8). The first precursor (2) and the second precursor (5) can be introduced into the plasma gas, preferably in monomeric form, preferably before the plasma gas enters the treatment region (8). it can. The system can be provided with means (not shown) for transporting the plasma gas to the processing area (8).

The first and second precursors (2, 5) can be introduced into the plasma gas in either atomized or sprayed liquid or vaporized forms, respectively. If the first and / or second precursor is not in liquid or gaseous form at room temperature prior to introduction into the plasma gas, it must be converted to a liquid or gas prior to introduction into the plasma gas. The first and second precursors may be introduced into the plasma gas continuously or discontinuously, respectively. In a preferred embodiment, the first and second precursors (2, 5) are introduced into the plasma gas in the form of aerosols (4, 7). Preferably, the system comprises an aerosol generator (3, 6) for each of the first and second precursors (2, 5).

In a preferred embodiment, the first and second precursors are co-injected into the treatment area at an essentially constant flow rate for each of the first and second precursors. This results in an essentially uniform coating. Preferably, the first and second precursors are at least 0.1 standard liter per minute (slm) and up to about 5 slm, respectively, for example, about 0.1 slm, about 0.125 slm, about 0.16 slm, about 0.2slm, about 0.25slm, about 0.315slm, about 0.4slm, about 0.5slm, about 0.63slm, about 0.795slm, about 1slm, about 1.26slm, about 1.58slm, about 2slm, about 2.5slm, about 3.16slm, about Atomized at a rate of 3.98slm, about 5slm, or any value in between. More preferably, the first and second precursors are atomized at a rate of at least 0.2 slm and up to 2 slm, respectively.

In an alternative preferred embodiment, the first and second precursors are co-injected into the treatment area with a gradual decrease in the flow rate of the second precursor and a gradual increase in the flow rate of the first precursor. Will be done. This results in a coating that includes a composition gradient. The flow rate of the second precursor can be linearly reduced during a period of time, preferably from the first maximum flow rate to essentially zero or negligible flow rate. The flow rate of the first precursor can be increased linearly during the time period, preferably from an essentially zero or negligible flow rate to a second maximum flow rate.

Alternatively, the decrease and increase can be performed according to a gradual profile, which includes: --first time zone in which only the second precursor is injected; --first precursor. Second time period, when the flow rate of the body increases and the flow rate of the second precursor decreases at the option; --The flow rate is non-zero for each of the first and second precursors and is essentially constant. There is a third time zone; --a fourth time zone where the flow rate of the second precursor decreases and optionally further increases the flow rate of the first precursor; and --only the first precursor is injected. The fifth time zone to be done.

The first, third, and fifth time zones may be omitted from the gradual profile, respectively. All of these modifications with respect to the stepwise profile result in a superhydrophobic coating that includes: --a first polymer layer that contains exclusively or primarily a second precursor on the inner coating surface; --on the exposed outer coating surface. A second polymer layer, exclusively or primarily containing a first precursor; and-a copolymer region between the first and second polymer layers.

In a preferred embodiment, the plasma gas is helium (He), argon (Ar), nitrogen gas (N).₂), Air, oxygen (O₂), Ammonia (NH₃), Methane (CH₄), Acetylene (C₂H₂), Carbon dioxide (CO₂), Hydrogen gas (H₂), Or a mixture thereof. More preferably, the plasma gas contains helium (He) or argon (Ar). In a preferred embodiment, the plasma gas has a gas flow rate of at least 1 slm and up to 100 slm, eg, about 1 slm, about 1.26 slm, about 1.58 slm, about 2 slm, about 2.5 slm, about 3.16 slm, about 3.98 slm, about 5 slm. , About 6.3slm, about 7.95slm, about 10slm, about 12.6slm, about 15.8slm, about 20slm, about 25slm, about 31.6slm, about 39.8slm, about 50slm, about 63slm, about 79.5slm, about 100slm, or in between Includes gas flow rate of arbitrary value. More preferably, the plasma gas comprises a gas flow rate of at least 5 slm and a maximum of 50 slm, for example a gas flow rate of about 20 slm. High plasma gas flow rates are advantageous because they allow impurities from the atmosphere to be reduced or maintained at essentially negligible levels. In a preferred embodiment, the residence time of the plasma gas in the treatment space is at least 0.01 seconds on average and 10 seconds at maximum. In a preferred embodiment, the coating has a deposition rate of at least 10 nm / min and up to 500 nm / min, eg, about 10 nm / min, about 12.6 nm / min, about 15.8 nm / min, about 20 nm / min, about 25 nm / min. , Approximately 31.6 nm / min, Approximately 39.8 nm / min, Approximately 50 nm / min, Approximately 63 nm / min, Approximately 79. 5nm / min, about 100nm / min, about 126nm / min, about 158nm / min, about 200nm / min, about 250nm / min, about 316nm / min, about 398nm / min, about 500nm / min, or any value in between It is deposited on the surface of the substrate at the deposition rate of. In a more preferred embodiment, the coating is at a deposit rate of at least 20 nm / min and up to 250 nm / min, even more preferably at a deposit rate of at least 50 nm / min and up to 160, eg, about 50 nm / min, about 60 nm. / Min, about 70 nm / min, about 80 nm / min, about 90 nm / min, about 100 nm / min, about 110 nm / min, about 120 nm / min, about 130 nm / min, about 140 nm / min, about 150 nm / min, about 160 nm Deposits on the substrate surface at a deposition rate of / min or any value in between.

The first precursor comprises at least one of the following polymerizable monomers or a derivative thereof: fluoro-acrylate monomer, fluoro-alkyl acrylate monomer, fluoro-methacrylate monomer, fluoro-alkyl methacrylate monomer, and fluoro-acrylate. Silane monomer. Thus, the first precursor can include one of these polymerizable monomers or derivatives thereof; or can include a plurality of these polymerizable monomers or derivatives thereof.

In a preferred embodiment, the first precursor is of the formula: CFR₁R₂-(CF₂)_n-(CR₃R₄)_mContains one or more monomers with -X. R₁And R₂Are independent of each other, hydrogen, fluorine, and fluoro-alkyl (C).₁~ C₄), Or CF₃Is. Preferably n is at least 3 and at most 30. R₃And R₄Are independent of each other and R₁And R₂Independent of hydrogen, alkyl (C₁~ C₄), Or hydroxyl. Preferably m is 1, 2, or 3. X is 0-CO-CR₅= CHR₆(In the formula, R₅And R₆Are independent of each other and R₁, R₂, R₃, And R₄Independent of, it may be a hydrogen or methyl group). Alternatively, X is Y-Si- (R₇)₃(In the formula, Y is oxygen or does not exist, R₇Is R₁, R₂, R₃, And R₄Independent of, it may be an alkoxy group).

In a more preferred embodiment, the first precursor comprises one or more monomers from the following polymerizable monomers: 1H, 1H-perfluorohexyl acrylate; 1H, 1H, 5H-octafluoropentyl acrylate; 1H, 1H-Perfluoroheptyl Acrylate; 1H, 1H, 7H-PerfluoroHeptyl Acrylate; 1H, 1H-Perfluorooctyl Acrylate; 1H, 1H-Perfluorodecyl Acrylate; 1H, 1H-Perfluorododecyl Acrylate; 1H, 1H, 2H, 2H-nonafluorohexyl acrylate; 1H, 1H, 2H, 2H-perfluoro-7-methyloctyl acrylate; 1H, 1H, 2H, 2H-perfluorooctyl acrylate; 2- (perfluoro-7-methyl) Octyl) ethyl acrylate; 1H, 1H, 2H, 2H-perfluorodecyl acrylate; Eikosafluoro-11- (trifluoromethyl) dodecyl acrylate; 1H, 1H, 2H, 2H-perfluorododecyl acrylate; 3- (perfluoro-3-) Methylbutyl) -2-hydroxypropyl methacrylate; 3- (perfluoro-5-methylhexyl) -2-hydroxypropyl methacrylate; 1H, 1H-perfluorohexyl methacrylate; 1H, 1H, 5H-octafluoropentyl methacrylate; 1H, 1H-perfluoro Heptyl methacrylate; 1H, 1H, 7H-perfluoroheptyl methacrylate; 1H, 1H-perfluorodecyl methacrylate; 1H, 1H-perfluorododecyl methacrylate; 1H, 1H, 11H-perfluoroundecyl methacrylate; 1H, 1H, 2H, 2H-nonafluoro Hexyl methacrylate; 1H, 1H, 2H, 2H-perfluoro-7-methyloctyl methacrylate; 1H, 1H, 2H, 2H-perfluorooctyl methacrylate; 2- (perfluoro-7-methyloctyl) ethyl methacrylate; 1H, 1H, 2H,2H-Perfluorodecyl methacrylate; Eikosafluoro-11- (trifluoromethyl) dodecyl methacrylate; 1H, 1H, 2H, 2H-Perfluorododecyl methacrylate; Di-isopropyl 1 (1H, 1H, 2H, 2H-Perfluorodecyl) silane; 1H, 1H, 2H, 2H-Perfluorooctanoic diethoxysilane; Trichloro (1H, 1H, 2H, 2H-Perfluorooctanoic) silane; 1H, 1H, 2H, 2H-Perfluoro-octyltrimethoxysilane; 3,3,3- Trifluoropropyltrimethoxysilane; (perfluoroalkyl) ethyl-triethoxysilane; nonafluorohexyl-triethoxysilane; and bis (trifluoropropyl) tetramethyldisiloxane.

In a particularly preferred embodiment, the first precursor comprises a fluoro-alkyl acrylate monomer. In the most preferred embodiment, the first precursor comprises a 1H, 1H, 2H, 2H-perfluorodecyl acrylate (PFDA) monomer, see FIG.

The second precursor comprises at least one of the following or a derivative thereof: linear siloxane, silane monomer, cyclosiloxane, and cyclosilane monomer. Thus, the second precursor can include one of these substances or derivatives thereof; or multiple of these substances or derivatives thereof.

In one embodiment, the second precursor is of formula R-Si (X)._nY_{3 ~ n}Can include substances represented by. R and X are independent of each other, an alkyl group, an aryl group, a substituted alkyl group, a substituted aryl group, an organic group containing a carbon-carbon double bond, an organic group containing a carbon-carbon triple bond, or an epoxy. It is a group. Y is a hydrogen, halogen atom, hydroxyl group, alkoxy group, or allyl group. n is an integer equal to 0, 1, 2, or 3. A non-limiting list of R and X examples includes alkyl groups containing about 1 to about 30 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, pentyl. , Hexyl, heptyl, octyl, dodecyl, cyclohexyl, etc .; halogen-substituted alkyl groups containing about 1 to about 30 carbon atoms, such as chloromethylene, trifluoropropyl, tridecafluoro-1,1,2,2- Includes tetrahydrooctyl and the like. R is an aryl group containing about 6 to about 60 carbon atoms, such as phenyl, alkylphenyl, biphenyl, benzyl, phenylethyl, etc .; a halogen-substituted aryl group containing about 6 to about 60 carbon atoms, For example, chlorophenyl, fluorophenyl, perfluorophenyl, etc .; hydroxyl-substituted aryl groups containing about 6 to about 60 carbon atoms, such as phenol, naphthol, cresol, binaphthal, etc .; alkyl of about 7 to about 60 carbon atoms. Substituted aryl groups such as methyl, ethyl, or propyl substituted aryl groups; cinide substituted aryl groups and amino substituted aryl groups containing nitrogen atoms, and 5 or 6 members containing nitrogen atoms. Aromatic groups; organic groups containing carbon-carbon double bonds of about 1 to about 30 carbon atoms, such as γ-acrylicoxypropyl groups, γ-methacryloxypropyl groups, and vinyl groups; about 1 Organic groups containing carbon-carbon triple bonds of about 30 carbon atoms, such as acetylenyl; organic groups containing epoxy groups, such as γ-glycidoxypropyl groups and β- (3,, It may contain 4-epoxycyclohexyl) ethyl groups and the like. A non-limiting list of Y examples includes halogen atoms such as hydrogen, chlorine, bromine, fluorine; hydroxyl groups; alkoxy groups such as methoxy, ethoxy, isopropoxy; and allyl groups.

In one embodiment, the second precursor is of the formula [-(R).₁R₂) SiO-]_zIt may contain a cyclic siloxane represented by, more specifically, a cyclopolydisubstituted siloxane. Where R₁And R₂Are independent of each other, alkyl groups of about 1 to about 30 carbon atoms, aryl groups of about 6 to about 60 carbon atoms, or substituted alkyl groups or substitutions of about 1 to about 30 carbon atoms, respectively. It is an aryl group. Where z represents an integer of about 3 to about 10.

In a preferred embodiment, the second precursor comprises one or more monomers from the following monomers: 1,3-diethenyl-1,1,3,3-tetramethyl-disiloxane; 1,3, 5-trimethyl-1,3,5-trivinylcyclotrisiloxane; 2,4,6,8-tetramethyl-2,4,6,8-tetraphenylcyclotetrasiloxane; 2,4,6,8-tetra Methyl-2,4,6,8-tetravinylcyclotetrasiloxane; 2,4,6-trimethyl-2,4,6-triphenylcyclotrisiloxane; 3- (trimethoxysilyl) propylmethacrylate; 3-glycid Xypropyltrimethoxy-silane; benzyltrimethoxysilane; bromophenylsilane; bromophenyltrimethoxysilane; cyanophenylsilane; cyanophenyltrimethoxysilane; cyclohexylmethyldimethoxysilane; decamethylcyclopentasiloxane; decaphenylcyclopentasiloxane; dimethyl Dimethoxysilane; dimethyl-methylhydrogensiloxane; dimethyl-methylvinylsiloxane; dimethyl-siloxane; diphenyldimethoxysilane; diphenyldisylanol; dodecamethylcyclohexasiloxane; dodecaphenylcyclohexasiloxane; ethyltrimethoxysilane; fluorophenylsilane; fluoro Phenyltrimethoxysilane; Hexamethylcyclotrisiloxane; Hexaphenylcyclotrisiloxane; Methyltriethoxysilane; Methyltrimethoxysilane; Octamethylcyclotetrasiloxane; Octaphenylcyclotetrasiloxane; Octyltrimethyloxysilane; Phenyltrimethoxysilane; propyltrimethoxysilane; p-tolyltrimethoxysilane; tridecafluoro-1,1,2,2-tetrahydrooctyltylmethoxysilane; trifluoropropyltrimethoxysilane; and vinyltrimethoxysilane.

In a particularly preferred embodiment, the second precursor comprises cyclosiloxane. A non-limiting list of suitable cyclic siloxane examples is 2,4,6,8-tetramethyl-2,4,6,8-tetraphenylcyclotetrasiloxane; 2,4,6,8-tetramethyl -2,4,6,8-Tetravinylcyclotetrasiloxane; 2,4,6-trimethyl-2,4,6-triphenylcyclotrisiloxane; 2,4,6-trimethyl-2,4,6-tri Vinyl Cyclotrisiloxane; Decamethylcyclopentasiloxane; Decaphenylcyclopentasiloxane; Dodecamethylcyclohexasiloxane; Dodecaphenylcyclohexasiloxane; Hexamethylcyclotrisiloxane; Hexaphenylcyclotrisiloxane; Octamethylcyclotetrasiloxane; and Octaphenyl Cyclotetrasiloxane is included. In the most preferred embodiment, the second precursor comprises 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane (V4D4), see FIG.

In one embodiment, the method according to the first aspect of the invention is performed under dynamic conditions, in which case at least a portion of the surface of the substrate becomes a plasma containing the first and second precursors in the first round. The exposed and treated portion of the substrate is exposed to the plasma containing the first and second precursors at least a second time, preferably multiple times, within the treatment area. Dynamic deposition conditions include the advantage of providing better coating microstructure and topography, i.e., more homogeneous and therefore better superhydrophobic properties.

Furthermore, the method according to the invention presents the advantage of being a one-step process. A curing step, or a further curing step, may not be performed. No further or post-treatment is required to control the roughness and / or the chemical composition of the surface.

In addition, this method has the advantage that it can be used on a wide range of substrates. Preferably, the substrate is a sheet. The coatable substrate may have a flat surface or a curved surface. The substrate can have various forms and shapes. The base material to be coated can be a foil, a plate, a film, a woven fabric material, a non-woven fabric material, or the like. The base material to be coated can include plastic, silicon, glass, metal, ceramic and the like.

Preferably, the superhydrophobic coating has a contact angle of at least 150 ° to water.

The substrate coating according to the second aspect of the present invention can be used as a water-repellent surface, preferably a fluid motion control surface, an ice-proof surface, an adhesion-prevention surface, an antifogging surface, or a self-cleaning surface in microfluidics. ..

The substrate coating of the present invention presents an amazing form. It comprises a nano-order domain that connects the hard regions with the sections of the soft lattice. The nano-order domains are homogeneously dispersed and randomly oriented. This results in a superhydrophobic coating with high resistance to polishing constraints and high elasticity.

The present invention will be further described by the following non-limiting examples which further illustrate the invention, but these are not intended to limit the scope of the invention and may be construed as limiting. Absent.

Example Example 1: Continuous injection vs. simultaneous injection In the method according to the first aspect of the present invention, the first and second precursors are simultaneously injected into the treatment area. Therefore, during the plasma treatment, copolymerization of the first and second precursor monomers occurs. In addition, nano-sized domains are formed that connect the hard regions to the soft lattice regions. As schematically shown in Figure 3, the nano-sized domains are essentially homogeneously dispersed and randomly oriented. A coating (24) is deposited on the substrate (20) by the method according to the first aspect of the invention, in which case a nano-sized domain is present, in which the hard nanodomain (22) is soft nano. It is bound to the domain (23), resulting in the coating being firstly hyperhydrophobic, secondly highly resistant to polishing constraints and thirdly highly elastic.

This should be contrasted with the alternating continuous injections of the first and second precursors in the treated area, see Figure 2, where in this injection there are alternating layers (on the top surface of the substrate surface). A coating (21) of the substrate (20) containing 22, 23) is provided, whereby the layers (22, 23) are stacked essentially orthogonal to the treated substrate surface.

Example 2: Coating with PFDA and V4D4 precursors In this example, the first precursor contains a 1H, 1H, 2H, 2H-perfluorodecylacrylate (PFDA; Figure 4) monomer and a second precursor. Includes 2,4,6,8-Tetramethyl-2,4,6,8-Tetravinylcyclotetrasiloxane (V4D4; Figure 5) monomer. A dielectric barrier discharge (DBD) system (Figure 1) is used, which has a gap of about 2 mm. DBD was generated between a grounded bottom aluminum electrode separated by a dielectric barrier material and two high voltage aluminum electrodes. The plasma discharge was generated by an AC power source that generated a sinusoidal voltage containing a frequency of about 1.5 kHz. Discharge has a power density of about 0.0625 W / cm²Met. For plasma polymerization, both PFDA and V4D4 atomizations were performed on the TSI3076 device to obtain precursor flow rates in the range 0.1 to 5 slm. The precursor was placed in a plasma gas containing He or Ar and containing a flow rate of about 20 slm. A deposition rate of about 100 nm / min was obtained. The gas mixture containing the precursor aerosol was injected directly into the soft plasma in the treatment area. Plasma discharge deposition was performed at atmospheric pressure and room temperature. The process was executed in dynamic mode. Calibration of both co-injected monomers was obtained by using mass spectrometry performed on the coating material.

Figure 6 shows the MALDI mass spectrum performed on the early V4D4 plasma polymer. Figure 7 shows the MALDI mass spectrum performed on the early PFDA plasma polymers. FIG. 8 shows a comparison of the MALDI mass spectra of a multilayer structure containing alternating layers (see Figure 2; top half of Figure 8) and coatings according to the invention (Figure 3; see bottom half of Figure 8). Despite the slight change in strength, all the peaks obtained for the multilayer structure can also be observed for the coating according to the invention. In each case, copolymerization has occurred. In the coatings according to the invention, copolymerization results in randomly oriented nanodomains.

The water contact angle can be adjusted by adjusting the mixture of introduced monomers and plasma conditions. The water contact angle was measured, and the contact angle from 150 ° to 170 ° was obtained.

The mechanical properties of the coating according to the invention can be adjusted by adjusting the mixture of introduced monomers. Figure 9 shows the increase in elastic modulus with increasing V4D4 content. The modulus of elasticity obtained is significantly greater than in the case of prior art multi-layer coatings, which otherwise have similar properties.