Polysilazane composition

Abstract

The present invention relates to a polysilazane composition, in particular a composition, the use of the composition for coating a substrate, and a substrate comprising a coating made from the composition.

Description

Technical Field

[0001] This invention relates to polysilazane compositions, particularly compositions for use in coating substrates, and substrates comprising coatings made from said compositions. Background Technology

[0002] Protecting various surfaces from contamination, including pollution and staining, is of paramount importance across a wide range of technological fields. Surfaces with antifouling or self-cleaning properties, such as resistance to the chemical and physical bonds of dust particles and other types of stains, are crucial not only for photovoltaic modules and solar thermal systems but also for general purposes, such as preventing fingerprints and smudges on smartphones or graffiti on walls, and making these surfaces easy to clean when soiled. Antifouling, stain-resistant, and corrosion-resistant properties are widely sought-after characteristics in coatings. Because the requirements for coatings used in a wide variety of fields differ, there is a continuous need for novel antifouling coatings that combine antifouling properties with specific coating features tailored to particular applications.

[0003] The antifouling properties of certain inert organic molecules, such as polymers, are related to their coefficient of friction (CoF). The lower the CoF, the smoother the surface becomes under load. For example, a low CoF makes it easier to remove any dirt that eventually accumulates on the surface with little or no mechanical damage. It can also cause larger impact particles, such as sand grains in a sandstorm, to bounce off the surface without causing significant abrasion. Furthermore, a low CoF is also desirable for enhancing the human experience, such as the smooth feel of new smartphone screens. One example of a coating that can possess such desirable properties is fluoropolymers, which can be used to achieve this soft, smooth feel along with good fingerprint and antifouling properties.

[0004] Furthermore, coatings with low refractive index are required. Refractive index is one of the most fundamental quantities in optics and optoelectronics, determining many quality factors of optical components such as reflectors, filters, and resonators. It determines the focusing power of lenses, the dispersive power of prisms, the reflectivity of lens coatings, and the light-guiding properties of optical fibers. When light enters a medium with a low refractive index, it deviates from the normal and refracts towards the surface of the medium.

[0005] Polysilazanes are a class of polymers characterized by their Si-N-Si backbone, and have attracted increasing interest in recent years due to their application in coatings. Depending on the type and formulation of the coating, polysilazane coatings can exhibit a range of advantageous properties; the high reactivity of polysilazanes can result in coatings with properties such as high hardness and weather resistance, excellent adhesion properties, scratch and abrasion resistance, low surface roughness, and high gloss on the painted surface. Excellent heat resistance, chemical resistance, and UV resistance have also been demonstrated. It has been reported that organopolysilazane coatings, when cured at room temperature, have a pencil hardness of 5H, compared to 5B for more widely used (poly)siloxane coatings under the same curing conditions. As shown in WO2014008443A2, other polysilazane coatings have coefficients of friction between 0.03 and 0.05, similar to the well-known anti-stick Teflon of 0.04, but with better scratch and abrasion resistance. Inorganic perhydropolysilazane coatings cured under UV light / H2O2 or H2O2 / 80°C have reportedly achieved a coating hardness as high as 3 GPa (due to SiO2 production), while coatings cured in air at 700-1000°C have an impressive hardness of 13 GPa, demonstrating the deep crosslinking of the polysilazane functional units. Unlike other common polymers, such as (poly)siloxanes, polyurethanes, epoxy resins, and PMMA, which are frequently used due to their ease of use and / or low reactivity under environmental conditions, polysilazanes are considered the ultimate binder in their class (polymers used in wet chemical formulations) due to their high reactivity. Although polysilazane coatings have been used for purposes such as permanent anti-fingerprint coatings on metal surfaces, as disclosed in US2008 / 0131706 A1, they have not yet been widely used as antifouling coatings.

[0006] Coating formulations comprising polysilazanes and other components are known in the art. One example is formulations of siloxane resins, organopolysilazanes, and polyhedral oligomeric silsesquioxanes containing alkyl or aryl groups, as described in US 9593241B2, which produce coatings with a refractive index of 1.52-1.54. Due to the high reactivity of polysilazanes to nucleophilic groups, additives used in coatings typically lack these groups or are kept at very low concentrations. Such nucleophilic groups, including hydroxyl, amine, and unsaturated bonds involving heteroatoms (e.g., carbonyl, S=O), are known to cause fragmentation of polysilazanes. However, these groups can be used to covalently bind additives to polysilazanes in coatings; therefore, their exclusion implies that the polysilazane and additive cannot be covalently and firmly bonded together, which can lead to negative effects such as leaching of the additive from the coating or phase separation.

[0007] Therefore, improved polysilazane coatings are needed. Attached Figure Description

[0008] Figure 1A high-magnification optical microscope image of the coating on sample 48T-2 is shown.

[0009] Figure 2 A high-magnification optical microscope image of sample 48T coating is shown.

[0010] Figure 3 A high-magnification optical microscope image of the 48T-40 coating sample is shown.

[0011] Figure 4 Optical microscopic images of the coating on sample 48T-2 are shown, illustrating its tribological behavior under applied loads of 20 (left side of the image) and 250 MPa (right side of the image).

[0012] Figure 5 Optical microscopic images of the 48T coating sample are shown, illustrating its tribological behavior under applied loads of 20 (left side of the image) and 250 MPa (right side of the image).

[0013] Figure 6 Optical microscopic images of the 48T-40 coating are shown, illustrating its tribological behavior under applied loads of 20 (left side of the image) and 250 MPa (right side of the image).

[0014] Figure 7 Optical microscopic images of the 48R coating sample are shown, illustrating its tribological behavior under applied loads of 20 (left side of the image) and 250 MPa (right side of the image).

[0015] Figure 8 The FT-IR spectra of sample MTDS-1, cured in a high-humidity atmosphere containing H2O2 vapor and cured in an ambient atmosphere, are shown. Summary of the Invention

[0016] In a first aspect, the present invention relates to the composition claimed in claim 1, wherein the composition comprises

[0017] i) Based on the weight of the composition, 0.5-30 wt% of a polysilazane component, wherein the polysilazane component is selected from the group consisting of organic polysilazanes, inorganic polysilazanes, and any mixture of two or more organic and / or inorganic polysilazanes;

[0018] ii) 0.1-15 wt% of POSS, comprising at least one nucleophilic group, based on the weight of the composition;

[0019] iii) Based on the weight of the composition, 0.0001-2 wt% of the quaternary ammonium salt R 1 R 2 R 3 R 4 N + X- , where R 1 R 2 R 3 and R 4 Each of the following is independently selected from the group consisting of alkyl, aryl, arylalkyl, alkoxysilyl, and alkenyl, wherein X is selected from F, Cl, Br, I, PF6 or BF4, and OH; and

[0020] iv) Inert solvents.

[0021] In a second aspect, the present invention relates to the use of the composition of any one of the preceding claims for coating a substrate.

[0022] In a third aspect, the present invention relates to a substrate comprising a coating, wherein the coating is at least partially made of the composition. Detailed Implementation

[0023] Unless otherwise defined, all technical terms, symbols, and other scientific terms used herein are intended to have the meaning commonly understood by one of ordinary skill in the art to which this invention pertains. In some instances, terms having their commonly understood meanings are defined herein for clarity and / or ease of reference, and the inclusion of such definitions herein should not necessarily be construed as indicating a material difference from what is commonly understood in the art.

[0024] In one aspect, the present invention provides a coating composition comprising a polysilazane component, POSS, and a quaternary ammonium salt. When the coating composition of the present invention is applied to a substrate, the cured coating has advantageous properties, such as favorable antifouling properties and / or a low refractive index.

[0025] As used herein, the term "obtained coating" refers to a coating obtained by applying a particular coating composition (optionally together with other components) to a substrate and then curing it to obtain a coating. This term may be used interchangeably with the term "coating" when the intended meaning is clear. As used herein, the term "coating" refers to any layer, film, or covering on the surface of an object (generally referred to as a "substrate"). A coating may be substantially continuous or discontinuous. It may cover the entire surface or only a portion of the surface. It may be a single-layer coating or a multi-layer coating. As used herein, the terms "cure" and "curing" refer to any type of toughening and / or hardening of the coating composition when applied to a substrate, and may or may not be actively induced, such as by heating, plasma, radiation, electron beams, and / or chemical additives.

[0026] Since all compositions disclosed and claimed herein can be used for coating purposes, such as for forming coatings, the terms "composition" and "coating composition" are used interchangeably.

[0027] This invention provides a coating composition comprising:

[0028] i) Based on the weight of the composition, 0.5-30 wt% of a polysilazane component, wherein the polysilazane component is selected from the group consisting of organic polysilazanes, inorganic polysilazanes, and any mixture of two or more organic and / or inorganic polysilazanes;

[0029] ii) 0.1-15 wt% of POSS, comprising at least one nucleophilic group, based on the weight of the composition;

[0030] iii) Based on the weight of the composition, 0.0001-2 wt% of the quaternary ammonium salt R 1 R 2 R 3 R 4 N + X - , where R 1 R 2 R 3 and R 4 Each of the following is independently selected from the group consisting of alkyl, aryl, arylalkyl, alkoxysilyl, and alkenyl, wherein X is selected from F, Cl, Br, I, PF6 or BF4, and OH; and

[0031] iv) Inert solvents.

[0032] The compositions of the present invention comprise a polysilazane component. The polysilazane component may comprise 0.5-30 wt% of a polysilazane component based on the weight of the composition, said polysilazane component being selected from the group consisting of organopolysilazanes, inorganic polysilazanes, and any mixtures of two or more organic and / or inorganic polysilazanes. Preferably, the polysilazane component is selected from organopolysilazanes, mixtures of two or more organopolysilazanes, or mixtures of one or more organopolysilazanes with one or more perhydropolysilazanes. As used herein, the term "organopolysilazane" ("OPSZ") refers to the formula [R'R"Si-NR"']. n Any polysilazane, wherein at least one of R', R" and R"' is an organic substituent and the remainder is hydrogen, wherein an organic substituent is defined as any substituent including carbon. The terms "perhydropolysilazane" ("PHPS") and "inorganic polysilazane" are used interchangeably to refer to the formula [H2Si-NH]. n Any polysilazane.

[0033] The polysilazanes present in the coating compositions of the present invention can be linear or branched. They can be cyclic. The polysilazane component advantageously includes organopolysilazanes, wherein one or more, preferably all, of the organic substituents are selected from linear, branched, cyclic, and / or aromatic C1-C6 alkyl groups, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, phenyl, vinyl-3-(triethoxysilyl)propyl, and 3-(trimethoxysilylpropyl). Preferably, one or more organic substituents are selected from methyl and ethyl. However, in some embodiments, one or more organic substituents are selected from linear or branched C5-C6 alkyl groups. 10 Alkyl groups, preferably branched C5-C 10 Alkyl groups. Advantageously, the organic substituents do not include triple bonds or double bonds other than C=C bonds. Organic substituents may include heteroatoms.

[0034] The polysilazane component may, for example, have a number-average molecular weight (Mn) in the range of 150 to 150,000 g / mol. As will be understood by those skilled in the art, the polysilazane component can be selected to obtain certain properties of the resulting coating, such as hydrophobicity, refractive index, and antifouling properties.

[0035] The inventors have observed that the addition of an organopolysilazane known under the trademark Durazane 1800 (“D1800”) (Structure I) to a composition comprising the organopolysilazane Durazane 1500 Rapid Cure (“D1500 RC”) has a positive effect on coating quality, particularly in the presence of a high concentration of nucleophilic groups on the POSS and / or a high concentration of another, more reactive polysilazane in the composition. The structure of D1500 RC is shown below (Structure II). a, b, and c are proprietary information unknown to the inventors. In addition to propyltriethoxysilane grafted onto the polymer backbone, D1500 RC may also contain 3-aminopropyltriethoxysilane (APTES) as an additional curing agent. According to information provided by the manufacturer Merck, the total amount of propyltriethoxysilane and APTES in D1500 RC is greater than 10% and less than 30% based on the total weight of the composition.

[0036]

[0037] Visual inspection revealed that the coating in Experiment 1 containing D1800 was smoother, more uniform, and exhibited better antifouling properties than the corresponding coating without D1800. These effects can be attributed to the fact that D1800 is more sterically hindered than D1500 RC, which may result in a slower and more controlled reaction; the vinyl groups of D1800 become ethyl groups upon curing, which are more hydrophobic than the methyl groups of D1800; and the higher number of organic groups in D1800 allows it to act as a surfactant, thereby improving the film-forming properties of the composition.

[0038] D1800, D1500 RC, and Durazane 1500 Slow Cure (“D1500 SC”) all represent examples of preferred polysilazane compositions. Information regarding the structure of D1500 SC, also manufactured by Merck, is not currently available, but it is believed that D1500 SC does not contain grafted triethoxysilane (Z=0), but has “free” APTES in the range of greater than 3 and less than 10% (hence its slower curing compared to D1500 RC). The organic group in D1500 SC is believed to be methyl.

[0039] The polysilazane component is present in amounts ranging from 0.5 to 30 wt%, such as 1 to 8 wt%, such as 5 to 15 wt%, or such as 20 to 30 wt%, based on the total weight of the coating composition. Those skilled in the art will understand that the amount of polysilazane can be selected, for example, based on the technique to be used to apply the coating composition to the substrate.

[0040] The compositions of the present invention comprise POSS, or polyhedral oligomeric silsesquioxanes, having the chemical formula [RSiO]. 3 / 2 ] n Compounds containing (R = H, alkyl, aryl, arylalkyl or alkoxy, fluoroalkyl, perfluoroalkyl, siloxane / (poly)siloxane, ether / polyether) can have a cage-like structure. Figure 1 It contains silicon dioxide (SiO2) and its chemical composition is between that of silicon dioxide (SiO2) and silicone (R2SiO). n Hybrid intermediates between (RSiO) 1.5 ) n Each POSS molecule may contain reactive functional groups suitable for polymerization or grafting POSS monomers onto polymer chains via covalent bonding, as well as non-reactive organic functional groups for the solubility and compatibility of POSS with various polymer systems. A range of different POSS molecules are available, with more under development.

[0041] The advantages of POSS include its small size (1-3 nm, Si-O-Si core), which makes it possible to mix with polysilazane at the molecular level, and its molecular-like rather than nanoparticle-like behavior, allowing for highly stable concentration and dispersion in various solvents. This is beneficial for the formulation of coating compositions. Furthermore, the Si-O-Si basis of the POSS molecule means that the light transmittance of the coating is not adversely affected when POSS is included in it.

[0042] When used in the coating compositions of the present invention, compared to comparable coatings that do not include POSS, the spherical nature of the POSS molecules can help reduce the coefficient of friction of the resulting coating when the rigid Si-O-Si framework is combined with and surrounded by low-friction (smoothing) molecules (e.g., alkyl or fluoroalkyl groups from polysilazane or POSS itself). POSS can be considered as a ball acting similarly to a roller of a smooth component.

[0043] The R group of POSS can be independently selected from the group consisting of or composed of: H, alkyl, aryl, arylalkyl, alkoxy, alkoxysilyl, or alkenyl. In some embodiments, the R group is selected from H, C1-C1, C2-C4, C3-C4, C5-C6, C4-C6, C5 ... 18 Alkyl, C6-C 24 Aryl, C7-C 34 arylalkyl, C1-C 18 Alkoxy, C1-C 12 (C1-C9 alkoxysilyl) alkyl and C2-C 18 Alkenyl groups, such as H, C2-C 12 Alkyl, C6-C 12 Aryl, C7-C 22 arylalkyl and C2-C 12 Alkoxy, C2-C8 (C1-C6 alkoxysilyl)alkyl and C4-C 12 Alkenyl groups, preferably selected from H, C1-C6 alkyl groups (such as methyl, ethyl, propyl, butyl, isobutyl, pentyl, hexyl, cyclohexyl), phenyl, C7-C... 18 Arylalkyl, C1-C6 alkoxy, C1-C6 (C1-C4 alkoxysilyl)alkyl, and C1-C6 alkenyl. Alkyl, arylalkyl, alkoxy, alkoxysilyl, and alkenyl groups can be straight-chain and / or branched. Alkyl, arylalkyl, alkoxy, alkoxysilyl, and alkenyl groups can be cyclic. The R groups can be all identical, or one, two, or more, or all R groups can be different from the other R groups.

[0044] Advantageously, alkenyl or alkoxysilyl groups can react after coating to covalently bond to the coating. Such bonding can prevent the leaching of unbound components such as salts. However, the number of such groups should not be too large; it should be limited to a maximum of five, such as a maximum of three. The presence of terminal methyl groups at any position in the POSS, such as in highly branched alkyl groups, can result in coatings with advantageous antifouling properties.

[0045] The POSS used in this invention comprises at least one group capable of reacting with polysilazane (covalently bonded to Si) to induce fragmentation. Unsaturated bonds, such as C=O and S=O, are not considered nucleophiles, but in some cases both can act as nucleophiles. The authors found that in our coating formulations, the carbonyl group in butyl acetate and the S=O group in dimethyl sulfoxide react with polysilazane. Therefore, the nucleophile used in this invention broadly includes unsaturated bonds capable of reacting with polysilazane to induce fragmentation. The nucleophile comprises heteroatoms selected from O, N, and S. The nucleophile may be selected from C=O, OH, NH2, NH, S=O, SH, C=N, and C≡N. In some embodiments, the nucleophile is selected from NH2, C=O, and OH. The nucleophile may be present as a substituent on the R group, or it may be directly bonded to the Si atom. In some embodiments, the POSS comprises 1-8, preferably 1-5, more preferably 1-3 nucleophiles.

[0046] The Si atoms in polysilazanes (Si-H, and possibly Si-NH-Si) are readily targeted by nucleophilic attacks. Therefore, the nucleophilic groups of the POSS molecule can react with the polysilazane in coating compositions. One possible mechanism is the nucleophilic attack of the POSS nucleophilic groups, forming an intermediate covalent bond with the Si atom, making Si five-coordinated, followed by bond breaking – in the case of Si-N bond breaking – leading to chain fragmentation of the polysilazane. The degree of fragmentation may depend on the type of nucleophile, the type of polysilazane, and / or its concentration.

[0047] POSS molecules can be open-cage or closed-cage, or have random or ladder-like structures. Closed-cage POSS molecules of various cage sizes, such as T8 cages (8 Si atoms, structure III), T10 cages, T12 cages, and any mixtures of two or more, may be particularly useful in the coating compositions of the present invention.

[0048]

[0049] Advantageously, the POSS further comprises at least one fluorine substituent. The fluorine substituent can be directly bonded to the Si atom. Advantageously, the fluorine substituent exists as a substituent on the R group, making the R group a fluorinated R group. In some embodiments, the fluorinated R group is based on a siloxane, such as a (poly)siloxane. Preferred POSS molecules comprise at least one group selected from fluoroalkyl, fluoroaryl, fluoroarylalkyl, fluoroalkoxy, fluoroalkoxysilyl, or fluoroalkenyl as the R group. In some embodiments, the R group is selected from C1-C1. 18 Fluoroalkyl, C6-C 24 Fluoroaryl, C7-C 34 Fluoroarylalkyl, C1-C 18 Fluoroalkoxy, C1-C 12 Fluoro(C1-C9 alkoxysilyl)alkyl and C2-C 18 Fluoroolefins, such as those selected from C2-C 12 Fluoroalkyl, C6-C 12 Fluoroaryl, C7-C 22 Fluoroarylalkyl and C2-C 12 fluoroalkoxy, C2-C8 fluoro(C1-C6 alkoxysilyl)alkyl, and C4-C 12 Fluoroolefins, such as those selected from C1-C6 fluoroalkyl groups (such as fluoromethyl, nonfluorohexyl, fluoroethyl, trifluoropropyl, pentafluorobutyl, isofluorobutyl, heptafluoropentyl, cyclofluorohexyl), pentafluorophenyl, C7-C... 18 Fluoroarylalkyl, C1-C6 fluoroalkoxy, C1-C6 fluoro(C1-C4 alkoxysilyl)alkyl, and C1-C6 fluoroalkenyl. Alkyl, arylalkyl, alkoxy, alkoxysilyl, and alkenyl groups can be straight-chain and / or branched. Alkyl, arylalkyl, alkoxy, alkoxysilyl, and alkenyl groups can be cyclic. The R groups can be all identical, or one, two, or more, or all R groups can be different from the other R groups. For all mentioned fluorinated R groups, the fluorinated R group can include one or more fluorinated substituents, such as 1, 2, 3, 4, 5, 6, 7, or more fluorinated substituents. In a preferred embodiment, the POSS comprises at least one C1-C6 fluoroalkoxy group with 1-15 fluorinated substituents. 10 Fluoroalkyl groups, as R groups.

[0050] In some embodiments, the POSS does not include fluorine substituents. In certain embodiments, the POSS comprises 5-7 R groups that are nonfluorinated and include aryl (such as phenyl) and alkyl (such as methyl and / or (poly)siloxane), and 1-3 R groups that are nonfluorinated and include one or more nucleophilic groups selected from or consisting of the group consisting of: C=O, OH, NH2, NH, S=O, SH, C=N, or C≡N.

[0051] Compared to POSS without fluorine substituents, POSS molecules with fluorine substituents can improve the antifouling effect of the resulting coating. Compared to POSS without fluorine substituents, POSS molecules with fluorine substituents can reduce the refractive index of the resulting coating. Furthermore, as shown in the following examples using CO-POSS, fluorinated POSS can also produce a lower coefficient of friction.

[0052] The 8, 10, or 12 Si centers of T8, T10, and T12 cage POSS structures allow for optimization of the coating composition and the surface chemistry of the resulting coating. For example, if low surface energy (antifouling properties) and a low coefficient of friction are desired, most centers can be borne with fluoroalkyl groups, while only one or two may be borne with reactive nucleophilic groups. Advantageously, the POSS structure allows for enrichment of the coating surface with CF2 and CF3 groups without introducing too many reactive groups, unlike most common molecules where each fluoroalkyl chain or other chain of interest has its own reactive and / or functional groups.

[0053] POSS may further or alternatively include other substituents not mentioned above, such as at least one chlorine substituent. POSS molecules may include groups or substituents as R groups or in R groups, which are specifically selected for their properties, such as antiviral agents, UV absorbers / stabilizers, IR absorbers, and / or upconversion phosphors.

[0054] In some embodiments, the preferred POSS is CO-POSS. CO-POSS has isobutyl groups bonded to all but one of the Si centers, and a mixture of propyl methacrylate and perfluorododecyl (-CH2CH2(CF2)7CF3) on the last Si center. This combination of R groups in CO-POSS results in the POSS having positive properties associated with fluorine substituents, and it is highly hydrophobic and capable of forming stable solutions with polysilazane, leading to a very uniform distribution of the POSS in the polysilazane matrix, as observed under a microscope.

[0055] Further preferred POSSes are those having a higher number of fluorinated R groups than CO-POSS, such as T8 POSS with up to seven fluorinated groups, or up to six fluorinated groups. Including these POSS molecules in the coating compositions of the present invention is expected to yield coatings with a low coefficient of friction and / or good antifouling / easy-cleaning properties relative to other comparable coatings. Examples of such preferred POSSes are T8 POSSes with fluorinated chains, such as CH2CH2(CF2)nCF3, where 0 ≤ n ≤ 8, more preferably where 0 ≤ n ≤ 7. POSSes with larger cage sizes can have a correspondingly higher number of fluorinated chains. Some non-limiting examples of useful POSSes (structures IV-VI) are shown below.

[0056]

[0057]

[0058] In some implementations, POSS with a fluorinated chain, such as (CF2), can be used. n CF3, where 0 ≤ n ≤ 8 (assuming T8 cage). These POSS molecules may optionally further include more nucleophilic and / or polar functional groups. This can contribute to improved solubility in solvents, especially for longer fluoroalkyl chains (e.g., n ≥ 3). In these embodiments, the coating composition may include a fluorinated solvent to further improve the solubility of such POSSes, such as a single solvent or, for example, in combination with another solvent. Those skilled in the art are familiar with various fluorinated solvents and compatible solvents for solvent mixtures. Compound VII is an example of a useful POSS with such a structure.

[0059]

[0060] All POSS molecules including fluorinated substituents may further include any other type of fluorinated and / or non-fluorinated R groups, such as, but not limited to, straight-chain or branched alkyl, aryl (e.g., phenyl), (poly)siloxane, and alkoxysilyl (alkyl-O-Si). The combination of fluorinated and non-fluorinated substituents can help improve the solubility of POSS, especially in non-fluorinated solvents. It can also reduce the tendency of fluorinated molecules (such as compounds including CF2 and / or CF3 groups) to stick together or separate into phases, a phenomenon that can lead to high surface roughness, blurred coatings, and even increased coefficients of friction. Alkoxysilyl groups, such as methoxysilyl and ethoxysilyl, hydrolyze very rapidly in the presence of moisture to form silanols, which facilitates the rapid curing of polysilazanes. POSS molecules may also be used that have only alkoxysilyl groups or are predominantly alkoxysilyl, with or without R groups containing reactive functional groups.

[0061] Examples of POSS molecules having a combination of fluorinated (trifluoropropyl) and nonfluorinated R (phenyl and isobutyl) groups used in this invention include:

[0062]

[0063] The authors have found that combinations of phenyl or alkyl groups (isobutyl, isooctyl, etc.) with fluoroalkyl groups (trifluoropropyl, heptafluoropentyl, etc.) result in better solubility of POSS in solvents and / or better dispersibility in polymer matrices, eliminating coating hazines common in structures IV and V, and providing overall improved coating quality, for example, based on visual observation. For instance, structure VIII was tested to show up to 40 wt% relative to polysilazane concentrations without exhibiting turbidity, unlike VI. The theoretical ratios shown in structures VII-XI are merely exemplary, as are the combinations of R groups.

[0064] The inclusion of one or more phenyl groups in the POSS molecule used in the compositions of the present invention can increase the toughness of the resulting coating, such as mechanical toughness as measured by tensile strength. Furthermore, it can improve resistance to destructive radiation, such as electrons, protons, and / or UV radiation in space. Therefore, in some embodiments, at least one R group comprises a phenyl group.

[0065] Furthermore, if the POSS contains naturally smooth R groups, the resulting coating has a relatively low coefficient of friction. Examples of such naturally smooth R groups are polyethers, (poly)siloxanes, and fluorinated chains.

[0066] Another POSS studied by the inventors is N-POSS, in which three of the eight R groups are 3-aminopropyl groups. The N-POSS molecule with three amino groups (assuming a T8 cage) reacts 3-6 times more vigorously with polysilazanes than the POSS molecule with only one OH or C=O group. Therefore, the reaction of N-POSS with polysilazanes is more vigorous than that of CO-POSS.

[0067] Furthermore, the POSS of the present invention may be non-fluorinated, but has an inert or R group containing an inert group. Examples of such inert groups include phenyl, alkyl, olefin, siloxane, and ether. The non-fluorinated POSS may have a combination of more than one R group. Such combinations, such as phenyl and vinyl, alkyl and vinyl, or alkyl and phenyl, can improve dispersibility and compatibility in solvents and coating matrices. Examples of non-fluorinated POSS include aminopropyl isobutyl POSS (structure IV, trifluoropropyl isobutyl substituted) and trisilyl isobutyl POSS (open cage). The latter was found to be too reactive, requiring a reduction in silanol concentration by reacting with a suitable silane to form a silyl ether.

[0068] The POSSes present in the compositions of the present invention typically have T8 cages (8 Si atoms), T10 cages, or T12 cages, or any mixture of two or more. POSSes with larger cage structures, such as T14 or T18, can also be used in the coating compositions of the present invention. In some embodiments, T8 is preferred. In other embodiments, T10 and / or T12 are preferred because they can provide greater mechanical strength to the coating. Furthermore, these may also result in slightly higher nanoporosity than their T8 counterparts due to their less dense packing compared to smaller T8s. So-called dumbbell-shaped and / or star-shaped POSSes may also be useful. In some embodiments, the POSS has a dumbbell shape, in which two POSS cages are connected together. In some embodiments, the POSS has an “extended dumbbell” shape, in which three, four, or more POSS cages are connected together. Such structures can advantageously include only 1-3 nucleophilic groups, such as two nucleophiles, preferably a single nucleophile. The low number of nucleophiles per POSS structure may result in lower reactivity, thereby increasing control over the reaction. The use of dumbbell-shaped POSSes can improve the distribution of the POSS cage throughout the composition, such as by making the POSS cage more uniformly distributed in the composition. This effect can lead to improved light transmittance of the resulting coating. Examples of useful POSSes with a dumbbell shape are shown below.

[0069]

[0070]

[0071] Due to the synthetic method employed, the dumbbell structures all possess a secondary amine as a reactive nucleophile. Other nucleophiles can be used. Furthermore, the ratio of R groups is exemplary. One or more R groups on one sphere of the dumbbell structure may differ from those on the other sphere.

[0072] POSS is present in the coating compositions of the present invention in an amount such as 0.1-15 wt%, 0.2-15 wt%, 0.5-10 wt%, or 1-5 wt% based on the weight of the coating composition.

[0073] Combinations of two or more POSS types can be used. For example, a POSS primarily containing a fluorinated group and one or two nucleophiles with R groups can be combined with another POSS containing an alkoxysilyl group and a fluorinated R group. Combinations of different POSS structures (T8, T10, T12, open or closed cages) can be used. POSS structures VIII, IX, and X were synthesized using methods designed to produce T8 structures and closed cages. However, NMR analysis revealed that for VIII and IX (a combination of phenyl and trifluoropropyl), approximately 2% to 4% of the product is open-cage, and for X, approximately 9% of the product is open-cage. Furthermore, the ratio of trifluoropropyl to non-fluorinated R groups differs slightly from theoretical values; the phenyl:trifluoropropyl POSS structure has a slightly higher trifluoropropyl content than theoretically expected, while the isobutyl:trifluoropropyl combination does the opposite. These variations in structure and R groups naturally apply to their derived dumbbell structures.

[0074] In some embodiments, the compositions of the present invention further comprise 0.005-5 wt%, such as 0.05-5 wt%, such as 1-3 wt%, of POSS excluding reactive nucleophilic groups based on the total weight of the composition.

[0075] The compositions of the present invention comprise compounds capable of promoting the reaction of the polysilazane component with POSS and / or causing anti-crushing of the polysilazane. The compound comprises a nucleophilic component, such as an anion. Preferably, the compound is a salt. More preferably, the salt is a quaternary ammonium salt R. 1 R 2 R 3 R 4 N + X - As used herein, the term "quaternary ammonium salt" refers to a positively charged monovalent group R with a tetravalent nitrogen and a negative counterion (anion). 1 R 2 R 3 R 4 Anion X - It can be selected from fluorides, chlorides, bromides, and iodides. Or, X - It can be a polyatomic anion, such as PF6. - Or BF4 - or OH - In some embodiments, X is selected from F, Cl, Br, I, PF6 or BF4 and OH. In some embodiments, X is selected from F, Cl and Br. 1 R 2 R 3 and R 4 Each of the following is independently selected from the group consisting of or including the following: C1-C 10Alkyl, aryl, arylalkyl, alkoxysilyl, and alkenyl groups are suitable. Advantageously, the alkoxysilyl group of an alkoxysilyl group can be hydrolyzed to a silanol, which can then undergo polycondensation with other silanols derived from the hydrolysis of polysilazane to obtain a covalently bonded coating. Other groups that can react with polysilazane or additive coatings to establish covalent bonds, such as alkenyl groups with activated C=C double bonds, are also advantageous.

[0076] This salt can promote the reaction of nucleophilic groups on POSS and / or other components of the coating composition with polysilazane. This activation may be X - The interaction with silicon atoms in polysilazane, such as coordination, results in the activation of silicon atoms to carry out nucleophilic attacks.

[0077] This salt can also act as a catalyst for anti-fragmentation. As discussed above, the presence of nucleophilic (reactive) centers in the POSS within the coating composition leads to the fragmentation of the polysilazane chains. Fragmentation may begin immediately after the polysilazane component and POSS are mixed. The resulting fragments may be volatile, less reactive than the original polysilazane, or even non-reactive. Due to their smaller size, they may be lost through evaporation. They may also leave unreacted polar groups in the cured coating, thereby reducing the antifouling properties of the coating.

[0078] While not wishing to be bound by any theory relating to their mechanisms of action, a possible explanation for the positive effects observed in the presence of quaternary ammonium salts, discussed experimentally below, may involve the fact that polysilazane fragments comprise NH2 and NH functional units, and that quaternary ammonium salts can promote the reaction of electrophilic Si atoms in Si-H with nucleophiles such as NH2 and NH. These properties could allow the fragments to recombine into a larger polymer network. Importantly, the anions of the salts are stronger nucleophiles than the reacting nucleophiles (NH2 and NH) and are capable of catalyzing reactions that can be described as follows:

[0079] Fragment -N-H+ chain -Si-H → Fragment -N-Si- chain + H2(g)

[0080] Here, "chain" refers to the chain of the polysilazane polymer backbone. Bubbling (i.e., gas evolution) observed when mixing polysilazane and catalyst supports this theory. If two different polymer backbones link together—which can also happen—this phenomenon is called solution crosslinking. Solution crosslinking can occur without POSS (or polysilazane fragments) because the NH groups of the polysilazane (Si-NH-Si) can react with Si-H in the presence of a catalyst, leading to the formation of Si-N bonds.

[0081] Preferred quaternary ammonium salts are commercially available tetrabutylammonium fluoride (TBAF), tetrabutylammonium bromide (TBAB), tetrabutylammonium chloride (TBAC), and tetrabutylammonium hydroxide.

[0082] Salt may be present in the coating composition in an amount of 0.0001-2 wt%, such as 0.001-1 wt%, such as 0.1-0.5 wt%, based on the weight of the composition.

[0083] The compositions of the present invention may include a curing agent. As used herein, the term "curing agent" refers to any compound known to those skilled in the art to promote the curing of a polymer by crosslinking polymer chains. Preferred examples of curing agents are 3-aminopropyltriethoxysilane (APTES), tetraethyl orthosilicate (TEOS), alkyltriethoxysilanes (e.g., ethyltriethoxysilane), and alkyltrimethoxysilanes. APTES is capable of reacting with polysilazanes due to its amino group and can therefore be considered a reactive additive, meaning that an anti-crushing catalyst may be required.

[0084] The alkoxysilyl group has low steric hindrance and can undergo rapid hydrolysis, resulting in the formation of silanols, which in turn enhances the curing of polysilazane.

[0085] Curing agents can be grafted onto polymer chains, as shown in D1500 RC.

[0086] The curing agent may be present in the coating composition in an amount of 1-30 wt%, such as 3-30 wt%, such as 3-10 wt%, such as 10-20 wt%, based on the weight of the polysilazane component.

[0087] The compositions of the present invention comprise an inert solvent. As used herein, the term "solvent" refers to a liquid substance in which a compound is soluble or partially soluble at a given concentration to dissolve or partially dissolve the compound. Unless the context otherwise requires, the term refers both to a solvent mixture (i.e., a solvent consisting of multiple components) and a pure compound (i.e., a solvent consisting of a single component). As used herein, the term "inert solvent" means a solvent known to those skilled in the art not to react with other components of the coating composition. The solvent should be present in an amount of 20-99 wt% based on the total weight of the composition. The solvent may be selected from a list including or consisting of: tetrahydrofuran (THF), 2-methyltetrahydrofuran (MTHF), dibutyl ether (DBE), perfluoromethoxybutane (MPB), cyclopentylmethyl ether, aromatic solvents such as xylene and toluene, and other polar aprotic and nonpolar solvents excluding functional groups that can react with polysilazane. It is typically an ether or a hydrocarbon. In some embodiments, the solvent is selected from a list including or consisting of: THF, DBE, MTHF, MPB, and xylene. THF, MTHF, and dibutyl ether are examples of preferred solvents. Solvents DMSO and butyl acetate can react with polysilazanes in the presence of TBAF or other catalysts and should therefore be avoided. Other solvents containing unsaturated bonds involving heteroatoms should also be avoided, as TBAF and other quaternary ammonium fluorides or catalysts can enhance the reaction of such double or triple bonds with Si-H.

[0088] In some embodiments, the compositions of the present invention further comprise one or more components selected from or consisting of the following: leveling agents, photoinitiators, fibers, polymer stabilizers, fillers, and pigments.

[0089] The compositions of the present invention may further include a leveling agent. As used herein, the term "leveling agent" refers to one or more compounds known to those skilled in the art that can enhance the uniformity of a coating and eliminate defects such as pores, "fish eyes," "orange peel," high roughness, etc. The leveling agent may be present in an amount of 0.01-1.5 wt%, such as 0.1-0.8 wt%, such as 0.3-0.5 wt%, based on the weight of the coating composition. The leveling agent may not have a reactive nucleophilic group selected from the group consisting of C=O, OH, NH2, NH, S=O, SH, C=N, or C≡N. An example of a leveling agent is a commercially available polyether siloxane copolymer… Glide 410 (TG4). In some embodiments, leveling agents comprising organofluorine groups are preferred, such as to obtain coating formulations with lower surface tension, particularly when using additives or polysilazanes containing fluorine substituents. A non-limiting example of a leveling agent having organofluorine groups is a derivative of the leveling agent reported in US20110319581A1, the structure of which is shown below (Structure XVII):

[0090]

[0091] Leveling agents should not react with polysilazane; therefore, in structure XVII, Rf can represent a straight-chain or branched perfluoroalkyl group containing 1-10 carbon atoms; X represents a trifluoromethyl group; Q can represent an ether containing 1 to 12 carbon atoms; R is an alkyl or acyl group containing 1 to 6 carbon atoms; R 1 and R 2 Independently, it is an alkyl group, aryl group, or arylalkyl group containing 1 to 10 carbon atoms.

[0092] The compositions of the present invention may further include a photoinitiator, such as 1-hydroxycyclohexylphenyl ketone. The photoinitiator may further contribute to the curing of the coating when UV or visible light aids curing. The photoinitiator may be present in an amount of 0.05-5 wt%, such as 0.1-4 wt%, or such as 0.3-1 wt%, based on the weight of the coating composition.

[0093] The compositions of the present invention may further comprise fibers, such as nanofibers, for example cellulose nanofibers. The fibers may have one or more alkyl and / or fluoroalkyl groups, as well as groups containing nucleophilic substances capable of covalently binding to the polysilazane. Containing fibers can reduce the refractive index of the resulting coating, for example by forming cavitation in the coating. The fibers can also improve the mechanical properties of the coating, such as impact toughness and tensile strength. The fibers may be present in an amount of 0.01-10 wt%, such as 0.1-7 wt%, such as 1-3 wt%, based on the weight of the composition.

[0094] The composition may further comprise one or more linear, branched, or cyclic (poly)siloxanes. An example is 1,3,5,7-tetramethylcyclotetrasiloxane (structure XVIII) shown below.

[0095]

[0096] Modification of structure X, in which one or more hydrogen atoms are replaced by alkyl, aryl, (poly)siloxane, organofluorine such as fluoroalkyl, reactive groups such as 3-aminopropyl or 6-hydroxyhexyl, and / or alkoxysilyl groups, may be preferred. The mentioned groups may have similar functions as present in polysilazane and / or POSS; for example, reactive groups may be covalently bonded to polysilazane; inert organic groups and organofluorine groups may improve the stability of the coating formulation and the antifouling properties of the resulting coating; alkoxysilyl groups may enhance the curing of polysilazane. (Poly)siloxane additives may be present in the coating formulation in an amount of 0.05-15 wt%, such as 0.08-10 wt%, such as 1-3 wt%, based on the weight of the composition. A particular advantage of (poly)siloxane additives is that they may not be as crystalline and rigid as POSS, thus improving the flexibility of the resulting coating. Other advantages may include improved light transmittance.

[0097] The compositions of the present invention may further comprise polymer stabilizers. As used herein, the term "polymer stabilizer" refers to any compound or composition that can inhibit or delay any degradation of the polysilazane component and / or coating. Common polymer degradation processes include oxidation, UV damage, thermal degradation, ozone decomposition, and combinations thereof, such as photo-oxidation, and reactions with catalyst residues, dyes, or impurities. Polymer stabilizers may be selected from the group consisting of or including: antioxidants, such as free radical scavengers, hydroperoxide scavengers, and anti-ozone agents; light stabilizers, such as UV stabilizers, quenchers, and hindered amine light stabilizers; acid scavengers; metal passivators; heat stabilizers; flame retardants; biocides; and any combination thereof. Preferably, the polymer stabilizer is a UV stabilizer, i.e., a compound or composition that prevents photodegradation of the polysilazane component or coating (e.g., by absorbing UV radiation).

[0098] The coating composition may further include one or more additional fillers and / or pigments, such as wollastonite, carbon black, mica iron oxide and / or thixotropic agents.

[0099] The compositions of the present invention can be coated onto a substrate and cured to obtain a coating. Therefore, in another aspect, the present invention relates to the use of any of the compositions disclosed herein for coating a substrate.

[0100] In another aspect, the present invention relates to a substrate comprising a coating, wherein the coating is made at least in part from any of the compositions disclosed herein. In some embodiments, the coating is made from the compositions disclosed herein.

[0101] The substrate can be made of any material. For materials with low surface energy (high water contact angle), surface activation may be required before coating. Such activation typically involves generating nucleophilic functional groups that will promote wettability, such as by coating the paint composition and by covalent bonding of the coating to the substrate, and can be achieved, for example, by atmospheric plasma, UV, or chemical treatment. Atmospheric plasma treatment may be preferred because it is potentially faster and safer. For example, the surface of polyethylene can be treated with atmospheric plasma for less than 30 seconds to generate functional groups such as hydroxyl, carbonyl, and carboxyl groups. Other substrates, such as glass, can also be treated to increase the concentration of nucleophilic functional groups and thus improve wettability and coating adhesion. These nucleophilic groups can covalently bond with polysilazane via Si-H, resulting in strong coating adhesion. When the substrate is glass, covalent bonds can also be formed based on the reaction of silanols on the glass surface with silanols generated from the hydrolysis of polysilazane, leading to Si-O-Si bonds. Atmospheric plasma activation of glass may increase the concentration of surface silanol groups and thus result in stronger coating adhesion.

[0102] The coating method disclosed in Norwegian patent application No. 20200778 or any patent or patent application arising therefrom or claiming priority thereto can be used for the preparation and / or application of coating compositions. Therefore, a polysilazane coating method for limiting polysilazane fragmentation can be used, the method comprising the following steps:

[0103] i) Preparing a coating composition, wherein the preparation of the coating composition includes the following sub-steps:

[0104] a. Introduce component A into the container of the coating composition;

[0105] b. Introduce component B into the container of the coating composition and mix component B with component A; and

[0106] c. Introduce component C into the container of the coating composition and mix component C with components A and B;

[0107] Components A, B, and C are each selected from the group of polysilazanes, the group of quaternary ammonium salts, or the group of reactive nanomaterials and / or reactive molecules, such as POSS, that can spontaneously react with the polysilazane polymer backbone to cause fragmentation.

[0108] Components A, B, and C are all selected from different groups;

[0109] The selection of each group of components A, B, and C is predetermined based on the known reactivity of the components with each other;

[0110] ii) Apply the coating composition to the substrate;

[0111] Step ii) is based on the known reactivity of the components with each other over a predetermined time period t. ii start.

[0112] You can choose the time period t ii such that 1≤t ii ≤1200 seconds.

[0113] The introduction of component C in sub-step ic) occurs within a predetermined time period t after the introduction of component B in sub-step ib). c Begin; and where t c Chosen as such that 0≤t c <900 seconds.

[0114] Alternatively, before applying the coating composition to the substrate, two or more components of the coating composition, such as all components, can be mixed together simultaneously, which means that t c =0, where the predetermined time period t after the mixing ii Apply the coating composition to the substrate starting at 1-1200 seconds, and where t ii It is predetermined based on the known reactivity of the components with each other.

[0115] In some embodiments, the polysilazane is mixed with any additive that does not react with the polysilazane (e.g., TG4), and the reactive additive (e.g., POSS) and quaternary ammonium salt are mixed separately. Other additives such as antibacterial agents, UV stabilizers, etc., may be added to the solution containing the polysilazane or the solution containing POSS, depending on their compatibility with the contents of such solutions. These two mixtures are combined and mixed. Then, after mixing these two mixtures, a predetermined time period t can be used. ii For example, 1-1200 seconds, the coating composition is applied to the substrate.

[0116] In some embodiments, polysilazane is mixed with any additive that does not react with polysilazane (solution A), and reactive additives (e.g., POSS) and quaternary ammonium salts are mixed separately (solution B), while a third mixture contains additives that can react with polysilazane, such as UV absorbers, photoinitiators, free radical curing agents, antibacterial agents, etc. (solution C). A and B are first mixed together, and C is introduced after 1-1000 seconds. Then, after mixing A and B, a predetermined time period t can be used. ii The coating composition is applied to the substrate starting at a time, such as 1-1200 seconds. The definition of a reactive additive can relate to the concentration and type of such additive. Reactive components can exist in such small amounts, for example, as part of an impurity or additive, without significantly disrupting the polysilazane. It can then be combined with the polysilazane in solution A.

[0117] The duration of solution C in the coating formulation prior to application (i.e., the time from the introduction of solution C to application by spraying) can be selected such that there is sufficient time for its contents to be uniformly mixed within the coating formulation, but short enough to limit the reaction of its contents with the polysilazane. This is to ensure that they remain active (e.g., as UV absorbers), because the activity of this group of additives is related to the presence of functional groups (e.g., hydroxyl, carbonyl) on them. Such functional groups are reactive with polysilazane. To further reduce the chance of reaction between the components of solution C and the polysilazane, the solution can be diluted, for example by adding an appropriate amount of solvent to solution C or by diluting the mixture of A and B before introducing solution C.

[0118] The coating formulation may or may not be diluted with an additional reactive component (solution C) before application.

[0119] Other coating methods, mixing methods and / or preparation methods known to those skilled in the art may also be used.

[0120] The coating composition can be applied to a substrate using any technique known to those skilled in the art, such as by methods selected from, but not limited to, spraying; such as ultrasonic spraying, such as painting, such as pneumatic spraying; spin coating; die casting; inkjet printing; doctor blade, electrospinning, and other processes known in the art for converting solution-treated chemical compositions into coatings or films. The advantage of using spraying is that a thinner coating composition can be used, resulting in a thinner film.

[0121] The thickness of the coating is typically in the range of 0.1 to 10 μm.

[0122] Curing can be assisted by plasma, heat, and one or more of UV or visible light, all in the presence of water and / or ammonia and / or H2O2 vapors. UV and plasma curing are rapid due to the presence of free radicals (e.g., hydroxyl radicals and ozone) or excited molecules (e.g., water). These high-energy molecules can induce rapid hydrolysis to form Si-OH and can further influence their energy on silanols for faster polycondensation. When exposed to moisture, Si-H and Si-NH-Si groups hydrolyze to produce silanols, which are then crosslinked to form Si-O-Si bonds. These reactions can also be enhanced with curing agents that are readily hydrolyzed upon exposure to air (e.g., APTES). The use of such curing agents is particularly important for organopolysilazanes, as their reactivity is sterically restricted. The alkoxy groups present in the polysilazane molecule can accelerate hydrolysis and crosslinking.

[0123] Rapid curing enables roller-to-roll coating. Complete curing can enhance abrasion resistance and / or anti-abrasion properties, and / or promote better antifouling properties, as all or most nucleophilic groups have been consumed. Rapid curing can advantageously be achieved by using atmospheric plasma and / or UV as curing methods, in an environment that can be air (normal), nitrogen, or a synthesis gas, with an appropriate level of relative humidity (RH), such as RH greater than 30%, for example, greater than 60%. The humidity in the environment can also be adjusted. Other preferred methods that can shorten the curing time compared to curing under standard atmospheric conditions include infrared heating in a humid atmosphere.

[0124] The embodiments and features described in the context of one aspect (e.g., with respect to the composition) also apply to other aspects of the invention, such as the use of the composition, such as substrates including coatings.

[0125] This invention should not be limited to the embodiments and examples shown. Although various embodiments of this disclosure have been described herein, it will be apparent to those skilled in the art that these embodiments are provided by way of example only. Many modifications and changes to the embodiments described herein, as well as variations and substitutions to these embodiments, will be apparent to those skilled in the art without departing from this disclosure. It should be understood that various alternatives to the embodiments described herein may be employed in practicing this disclosure.

[0126] It should be understood that each embodiment of this disclosure may optionally be combined with any one or more other embodiments described herein.

[0127] It should be understood that each component, compound, or parameter disclosed herein should be interpreted as disclosed for use alone or in combination with one or more of each and every other component, compound, or parameter disclosed herein. It should also be understood that each amount / value or range of amounts / values ​​of each component, compound, or parameter disclosed herein should be interpreted as also disclosed in combination with each amount / value or range of amounts / values ​​of any other one or more components, one or more complexes, or one or more parameters disclosed herein, and for the purposes of this specification, any combination or range of amounts / values ​​of two or more components, compounds, or parameters disclosed herein is therefore also disclosed in combination with each other. Any and all features described herein, as well as combinations of such features, are included within the scope of this invention, provided that such features do not contradict each other.

[0128] It should be understood that, for the same component, compound, or parameter, each lower limit of each range disclosed herein should be interpreted as a disclosure in combination with each upper limit of each range disclosed herein. Thus, a disclosure of two ranges will be interpreted as a disclosure of four ranges derived by combining each lower limit of each range with each upper limit of each range. Thus, a disclosure of three ranges will be interpreted as a disclosure of nine ranges derived by combining each lower limit of each range with each upper limit of each range, and so on. Furthermore, the specific amount / value of a component, compound, or parameter disclosed in the specification or embodiments should be interpreted as a disclosure of a lower or upper limit of a range, and therefore can be combined with any other lower or upper limit or the same component to form a range for that component, compound, or parameter.

[0129] Example

[0130] Coating composition (Experiment 1)

[0131] Table 1: Coating Compositions

[0132]

[0133] In Table 1, PS refers to polysilazane; D1500, D1500 SC, and D1500 RC, as well as TG4, are as defined above; and PI refers to the photoinitiator 1-hydroxycyclohexylphenyl ketone. Due to the decomposition of the stock solution, the concentration of D1500 RC may be as low as 30-40% lower than shown in the table.

[0134] method

[0135] Preparation of coating compositions

[0136] Unless otherwise specified, the coating composition is prepared by mixing polysilazane and TG4 (if present) separately in one container, mixing the other components (POSS, TBAF and PI) in another container, both containers further containing a solvent (THF), and then combining the two mixtures and mixing for five minutes.

[0137] Coating

[0138] The coating composition is applied to the glass substrate by dripping and spreading with a glass rod.

[0139] Curing

[0140] Curing is accomplished by treating with UV (405 and 360nm lamps) for 10 minutes, followed by continuous heating on a hot plate at 150°C for 50-60 minutes at a relative humidity of ≥40%.

[0141] Surface roughness

[0142] Surface roughness was measured using a Mitutoyo Surftest SJ 301 surface profilometer. The reported roughness value Ra (mean or average roughness) is the arithmetic mean of the absolute values ​​of the roughness profile coordinates.

[0143] Wear test

[0144] Tribological studies were conducted on a one-way ball-disc tribometer (Phoenix Tribology Ltd., Newbury, UK), in which a fixed ball... The coating was pressed onto a rotating surface. Tests were conducted as follows: using alumina balls as the counterpart, the maximum Hertzian contact pressure was approximately 250 MPa, and using Teflon balls as the counterpart, it was 20 MPa. For each test, 120 cycles were performed (radii of 5 and 4 mm, respectively). The test duration was set to 1 minute. Before each test, the balls were ultrasonically cleaned in ethanol for ten minutes, followed by rinsing with fresh ethanol and drying with pressurized air. The coating was purged with air to remove any present solid particles. The tested surfaces were examined using an optical microscope to assess coating damage. Higher contact pressure tests were also conducted at 500 MPa (alumina balls) and 40 MPa (Teflon balls).

[0145] Permanent Marking Test

[0146] The permanent marking test is used as a measure of stain resistance and is applicable to fingerprint resistance, stain resistance, and graffiti resistance. A permanent mark is applied to the coating, and its effect is observed. Stain resistance is considered to be present when the mark forms beads (dashed lines) or shrinks significantly compared to uncoated glass. After 10-60 seconds, the permanent mark line is wiped with a paper towel to determine how easily dirt can be removed. For uncoated glass, the mark cannot be wiped off even with significant force during wiping, and may only occasionally spread along the edges (forming a stain).

[0147] CoF test

[0148] The CoF of coating 48T-2 was measured using the tribometer described in Section 5, wherein the fixed spheres were made of alumina or Teflon. The coating was pressed onto a rotating surface. Initially, tests were conducted using a 2N load, with alumina balls as the counterpart, yielding a maximum Hertzian contact pressure of approximately 500 MPa, and Teflon balls as the counterpart, yielding 40 MPa. In this document, the terms "load" and "Hertzian contact pressure" are used interchangeably. Subsequent tests were conducted on coatings 48T-2 and 48T with a 1N load, corresponding to maximum Hertzian contact pressures of 20 MPa (Teflon balls) and 250 MPa (alumina balls).

[0149] Results and Findings

[0150] Pure polysilazane, N-POSS and TBAF

[0151] The coating of sample 61, which does not contain POSS, showed no antifouling effect in the permanent marking test, indicating that the antifouling effect of pure polysilazane coatings without performance-enhancing additives is limited. Furthermore, the markings were only slightly rubbed off.

[0152] The coating of sample 62, containing N-POSS, yielded worse results than 61, showing no antifouling effect and no indication that any permanent markings were wiped off. These observations can be explained by the following: reactive N-POSS generates a large number of polysilazane fragments, producing unreacted polar groups (e.g., NH2, NH, and Si-H), which lead to strong bonding between the markings and the coating. This demonstrates the importance of the presence of quaternary ammonium salts as described above. It should be noted that, visually, 62 appears smooth, comparable in appearance to the smooth 48 coating, and significantly better than 46, 50, and 48R (below). However, its surface roughness ranges from Ra 0.03±0.01 to Ra 0.1±0.01 nm, indicating the effect of fragmentation. However, its upper limit of surface roughness is similar to that of 50. Therefore, its limited / poor antifouling characteristics are not related to the high surface roughness, as 50 exhibits significant repulsion and easy wiping of permanent markings.

[0153] In the coating composition of Sample 50, larger particles formed in solution compared to Samples 61 and 62. A possible explanation for this observation is that the composition of Sample 50 contains TBAF; therefore, some degree of solution crosslinking and anti-fragmentation can be expected. Furthermore, N-POSS is highly reactive, which may also affect precipitate formation. The presence of precipitates may be the reason for the high surface roughness of the coating. Interestingly, although the coating of Sample 50 exhibits significantly higher surface roughness and poorer film quality than Samples 61 and 62, it shows a marked repellency to permanent markings that are easily rubbed off.

[0154] The coating of sample 46 differs from that of sample 50 in that it contains polysilazane D1800 in addition to D1500 RC. This coating has a higher surface roughness but is still repellent to permanent markings, albeit less than 50. This further indicates that the coating of sample 62 is not repellent to permanent markings regardless of surface roughness.

[0155] Adding a photoinitiator to samples 50 or 46 showed no effect on surface roughness or permanent mark repulsion. The intended function of the photoinitiator is to improve the curing of the coating under UV light, but further experiments showed no significant benefit. This may be related to the fact that the photoinitiator itself can react with polysilazane via its carbonyl and / or hydroxyl groups, a process that may render it unresponsive to UV light. Direct UV heating (with or without moisture) may also mask the photocuring effect of the photoinitiator.

[0156] CO-POSS

[0157] In these experiments, highly reactive N-POSS was replaced by CO-POSS with a large number of inert R groups, representing a completely different type of POSS.

[0158] Aside from the choice of POSS, the coating of sample 48T is a mirror image of sample 50. Visual inspection revealed that it is smoother and has higher optical quality than 46 and 50, while also providing better stain resistance / ease of cleaning characteristics than 50 in the permanent marking test. Therefore, a more detailed study of the surface roughness, coefficient of friction, and abrasion resistance of the 48 series was conducted.

[0159] For sample 48T-2 (which is the exact same coating composition as 48T), it was applied to a glass substrate after only two minutes of mixing. The resulting coating exhibited a very smooth surface, as evidenced by a surface roughness Ra of 20 ± 10 nm, similar to the surface roughness of the bare glass substrate.

[0160] To evaluate the effect of mixing time, sample 48T-40 (the same coating composition as 48T) was prepared, but the composition was applied to a glass substrate after 40 minutes. Figure 1 , Figure 2 and Figure 3 High-magnification optical microscopic images of the coatings for samples 48T-2, 48T, and 48T-40 are shown. These images reveal how the coating for 48T consists of larger dendritic grains, which are not prominent in 48T-2. For 48T-40, these dendrites have grown large enough to produce optical (color pattern) inhomogeneities under an optical microscope. Visually, the coating for 48T-40 appears to remain transparent.

[0161] In the wear test, the coating of sample 48-T2 showed slight wear, which was interpreted as merely polishing at both 20 and 250 MPa. 48T showed no wear at 20 MPa but slight wear (polishing) at 250 MPa. Under Hertzian contact pressures of 20 and 250 MPa, 48T-40 completely wore down, exposing the bare glass, indicating poor coating adhesion and curing properties. Figure 4 , 5 Figures 6 and 7 show the tribological behavior of the coatings of samples 48T-2, 48T, and 48T-40, respectively.

[0162] A possible explanation for the poor abrasion resistance of the 48T-40 coating is that excessive solution crosslinking occurred before application, resulting in an undesirable concentration of Si-H and Si-NH-Si functional groups. These groups are necessary for post-coating curing, and the Si-H groups are also crucial for covalent bonding to glass substrates or any other substrates with nucleophilic groups (such as hydroxyl, carbonyl, carboxyl, etc.).

[0163] The reason why 48T has better tribological properties compared to 48T-2 is likely due to the solution crosslinking producing a higher molecular weight polysilazane, but not as high as in 48T-40. This hypothesis is supported: 48T has a higher surface roughness compared to 48T-2. Since 48T is expected to have fewer available functional groups than 48T-2, adhesion or curing may not be a factor. It can be assumed that the concentration of functional groups in 48T-5 is sufficient for post-coating curing and adhesion. This, in turn, indicates a balance between high molecular weight polymers or polymer-POSS and post-treatment, achieved through optimal mixing time before application.

[0164] It's important to note that anti-fingerprint and anti-smudge coatings typically applied to glass (such as smart screens, glasses, and solar panels) are usually prepared from fluorinated polymer chains with silanoxy or acrylate end groups for adhesion and curing. Typical applied loads for abrasion testing are approximately 0.1 MPa (1 kg / cm²). 2 ), such as Shin-Etsu SUBELYN TM (Perfluoropolyethers with Si alkoxy end groups) and Daikin Chemicals OPTOOL DSX-E (a fluoropolymer with Si alkoxy end groups). Examples of applying lower loads are also available in the literature. The abrasion tests of coatings made from the coating compositions according to the invention showed much higher loads, indicating a stronger and considerably more durable coating for antifouling applications.

[0165] A variant of 48T, named 48R, was also prepared, in which D1500 RC was replaced by the more "reactive" D1500 SC. D1500 SC exhibited higher solution reactivity than 1500 RC, which can be attributed to a higher concentration of Si-H groups at the same molecular weight. Upon coating application, D1500 RC was more reactive (cured faster) due to the higher concentration of APTES.

[0166] Even with the presence and stabilizing effect of CO-POSS, the reactivity of the coating solution became as intense as that of 50 and other similar samples, resulting in a coating consisting of a smooth surface sprinkled with large and agglomerated particles, such as... Figure 7 As can be seen. Although transparent and exhibiting the same good stain resistance as the 48 series (permanent mark adhesion and easy wiping), the visible roughness of the coating makes it less suitable for surprise applications. Interestingly, the 48R sample showed no signs of wear (polishing or deep wear) at 250 MPa.

[0167] Effect of solvent

[0168] Some ready-to-use formulations of the OPSZ brand are made with butyl acetate as the main or sole solvent. Some manufacturers also recommend using dibutyl ether to dilute PHPS. Butyl acetate is likely to react with PHPS, which explains why it is not on the list of recommended solvents for PHPS. The authors found that n-butyl acetate was reactive to OPSZ in coating compositions in the presence of TBAF, resulting in complete wear of the coating at a 20 MPa Hz contact pressure. Large particles and color patterns, as seen in 48T-40, were also observed in coating compositions containing butyl acetate. This may indicate excessive consumption of Si-H functional groups by the carbonyl groups of the solvent (this process was enhanced by the catalyst TBAF), confirming that Si-H can react with unsaturated bonds in the presence of a catalyst. Therefore, solvents containing unsaturated bonds involving heteroatoms are not preferred for polysilazane compositions when using TBAF or catalysts with similar performance.

[0169] Coefficient of friction (CoF)

[0170] In the CoF test, sample 48T-2 was compared with polished Teflon. For the Teflon counterpart (40 MPa) and the alumina counterpart (500 MPa), pure and well-polished Teflon sheets gave CoFs of 0.05–0.06 and 0.07–0.08, respectively, while the CoFs for both counterparts of sample 48T-2 were 0.01–0.015. Further testing on 48T-2 at a lower Hertz contact pressure of 250 MPa (alumina spheres) showed CoFs of 0.03–0.04. 48T-2 was chosen because of its smoother surface and polishing properties. However, further testing on 48T at 20 MPa (Teflon spheres) and 250 MPa (alumina spheres) showed CoF values ​​of 0.02–0.03, slightly lower than 48T-2. These results indicate that the CoF of the 48 series coatings is very low.

[0171] Typically, the expected CoF is related to the applied load, meaning that for higher loads, a higher CoF is expected to be measured. However, the opposite trend was observed in the 48T-2 coating. An explanation for this observation might be that the spherical POSS additive can transform sliding friction in the contact / interface into rolling friction, thus enabling the lubrication mechanism to function as a nanobearing.

[0172] Further experiments (part of the planned experiments)

[0173] Experiment 2

[0174] Compared to fully fluorinated POSS (e.g., structure IV), POSS samples with a mixture of fluorinated and non-fluorinated R groups produced better coating properties, primarily the absence of turbidity and uneven appearance, and especially better visual appearance in the case of ultrasonic spraying. Dumbbell-shaped POSSes were generally better in terms of coating hardness, lower refractive index, and visual appearance.

[0175] Table 2 below shows the effect of POSS XIII concentration on the hydrophobicity and surface roughness of the coating. To prepare the coating, D1500RC (200 μl) and TG4 were mixed in an Eppendorf tube (solution A, total volume 0.5 mL). Solution B (total volume 0.5 mL) contained different concentrations of POSS XIII relative to the polysilazane and TBAF. The two solutions were mixed and combined by vortexing to produce a composition with 22 wt% polysilazane, 0.03 wt% TBAF, and 0.6 wt% TG4. As previously mentioned, the percentage of curing agent in D1500 RC relative to the polysilazane molecules is reported to be between 10 and 30 wt%. After mixing solutions A and B for 5 minutes, 200 μl of the resulting solution was dropped onto a glass slide and spread with a glass rod. The coating was dried on a hot plate maintained at 100°C for 10 minutes. The coating was then cured in a high-humidity atmosphere containing H2O2 vapor.

[0176] The locally manufactured apparatus was used to measure WDRV—the volume of water that rolls off the coating surface at a 45-degree angle (μl), and the angle of slip (SA), which is the angle at which 12 μl of water begins to slide off the coating surface.

[0177] All coatings demonstrate resistance to permanent marks—curling edges and easy wiping.

[0178] To minimize the impact of the more hydrophobic D1800, only 1500RC was used. For the coating without POSS or catalyst (PS+TG4), WDRV and slip angle were significantly higher, indicating poorer cleaning and water resistance. FT-IR data also showed lower cure levels compared to coatings with POSS.

[0179] For coatings with 3 wt% XIII, the lowest WDRV and SA were recorded, with 1.5 wt% showing more or less similar values. Further increasing the POSS concentration to 4.5 wt% resulted in higher WDRV and SA compared to coatings with lower POSS concentrations. This is likely due to the increased fragmentation effect with increasing POSS content, an effect that could be offset by increasing TBAF content. The latter is not without its limitations: increasing the amount of catalyst leads to higher reactivity (proven by stronger foaming), which increases the difficulty of controlling the coating process. However, the hydrophobicity of the 4.5 wt% POSS coating is still superior to that of PS+TG4.

[0180] Table 2

[0181]

[0182]

[0183] The higher surface roughness of coatings containing POSS and TBAF is likely due to reactions in the coating formulation—solution crosslinking and the bonding of POSS to the polymer chains.

[0184] Experiment 3 D1500RC (360 μl), D1800 (40 μl), MTHF (800 μl), and TG4 were mixed in an Eppendorf tube (solution A, total volume 1.4 mL). Solution B (total volume 2.6 mL) contained dibutyl ether (1600 μl), TBAF, and POSS XIV. The two solutions were mixed and combined by vortexing to produce a composition containing approximately 12 wt% polysilazane, 0.012 wt% TBAF, and 0.3 wt% TG4. After mixing for 5 minutes, 200 μl of the resulting solution was dropped onto a glass slide and spread with a glass rod. The volume ratio of MTHF:DBE in the coating formulation was 1.5:1. TG4, POSS XIV, and TBAF were dissolved in MTHF only before taking an appropriate volume for use in the coating formulation.

[0185] The coatings were dried in an oven maintained at 80°C for 10 minutes. Additionally, MTDS-1 and MTDP-1 were cured in a high-humidity atmosphere containing H2O2 vapor. After the drying step, MTDS-4 was left in the ambient environment. To allow sufficient time for MTDS-4, the pencil hardness of these coatings was analyzed after 14 days; the results are presented in Table 3.

[0186] Table 3

[0187] sample POSS XIV (wt%) Pencil hardness MTDS-1 2.25 4H MTDS-4 2.25 3B MTDP-1 1.125 2H

[0188] The hardness difference between MTDS-1 and MTDP-1 demonstrates the importance of the optimal POSS concentration for coating hardness.

[0189] The poor pencil hardness of MTDS-4 is due to the suboptimal curing of the polysilazane (Si-NH-Si hydrolysis and Si-H to form Si-OH, which then condenses to form Si-O-Si). This is confirmed by FT-IR spectroscopy. Figure 8 The spectrum shows that, compared to other coatings, the Si-NH-Si and Si-H coatings have significantly higher performance at approximately 900 and 1260 cm⁻¹, respectively. -1 The peak position at that point remains strong in MTDS-4. The authors also found that the hydrolysis and condensation of these functional groups were limited for the reference sample (lacking POSS or TBAF or both), especially Si-NH-Si.

[0190] The presence of uncured polar groups (Si-NH-Si and Si-H) limits the application of coatings in environments with humidity and contaminants, especially contaminants that can form hydrogen bonds, covalent bonds, or chemical interactions with them. For example, the authors found that wiping coatings cured under ambient conditions or cured only with water vapor with a cloth impregnated with acetone or isopropanol within 24 hours of coating preparation may damage the coating.

[0191] All coatings in Table 3, including MTDS-4, show repulsion to permanent markings. The glass slide substrate was plasma-activated (after cleaning) for 15 seconds using a diffused coplanar surface barrier discharge (DCSBD) atmospheric plasma system.

[0192] Experiment 4

[0193] D1033 (80 μl), D1800 (20 μl), THF:MPB (1:1) (300 μl), and TG4 were mixed in an Eppendorf tube (solution A, total volume 500 μl). Solution B (total volume 500 μl) contained THF, MPB, TBAF, and POSS X. The two solutions were mixed and combined by vortexing to produce a composition having approximately 10 wt% polysilazane, 0.5 wt% TG4, and 2.7 wt% POSS X. After mixing solutions A and B for 5 minutes, 200 μl of the resulting solution was dropped onto a glass slide and spread with a glass rod. The volume ratio of THF to MPB was approximately 3.5:1. TG4, POSS X, and TBAF were dissolved in THF only before taking an appropriate volume for coating formulation.

[0194] The coating was dried in an oven at 80°C for 10 minutes and then cured in a high-humidity atmosphere containing H2O2 vapor.

[0195] Table 4

[0196] TBAF wt% Refractive index 0 1.49 0.011 1.468 0.022 1.442 0.033 1.445 0.044 1.457

[0197] Based on the amount of reactive POSS, there exists an optimal concentration of catalyst (TBAF) that yields the lowest refractive index. The high refractive index of the reference coating with 0 wt% TBAF can be attributed to the inhomogeneity of the surface roughness and / or the relatively high concentration of polar groups in the polysilazane (poor or limited hydrolysis and polycondensation), as seen in the infrared spectroscopy. The slight increase in refractive index after 0.22 wt% TBAF may indicate excessive cross-linking of the solution, as shown in 48-T40, which could lead to larger particles in the coating.

[0198] Experiment 5D1500RC (720 μl), D1800 (80 μl), THF (1600 μl), and TG4 were mixed in an Eppendorf tube (solution A, total volume 2.800 mL). Solution B (total volume 5.200 mL) contained dibutyl ether (3200 μl), TBAF, and POSS VIII. The two solutions were mixed and combined by vortexing to produce a composition having 11.4 wt% polysilazane, 0.013 wt% TBAF, 0.3 wt% TG4, and 2.3 wt% POSS VIII. The volume ratio of THF to DBE was 1.5:1. POSS VII, TG4, and TBAF were dissolved in THF only before taking an appropriate volume for coating formulation.

[0199] After mixing solutions A and B for 5 minutes, 4 ml of the resulting solution was placed into a syringe and installed in an ultrasonic sprayer obtained from LRSAS. The nozzle frequency was 45 Hz, and the syringe speed (liquid flow rate) was 35 mm / s, operating at 50% power output. Plasma-activated (15 s) and unactivated glass slides were used as substrates. The coatings were dried in an oven at 80°C for 10 min and cured in a high-humidity atmosphere containing H2O2 vapor. For the plasma-activated substrates, the pencil hardness of the coatings after 48 hrs and 7 days was F and 2H, respectively. For the coatings on the unactivated substrates, the values ​​after 48 hrs and 7 days were B and HB, respectively.

[0200] Therefore, plasma activation enhances coating adhesion through better wetting.

[0201] Experiment 6

[0202] The preparation steps, composition, drying and curing of the coating were the same as in Experiment 5, except that MTHF was used instead of THF and POSS XV was used instead of POSS VIII.

[0203] Clean the uncoated and hard-coated flat polysulfide (PTU) lens material and plasma-activate it for 15 s before ultrasonic spraying. For transmittance studies, the coating is applied to both sides of the flat substrate.

[0204] With the coating applied to both sides of the PTU substrate, an increase in transmittance of approximately 4% to approximately 5% was recorded for both hard-coated and uncoated PTU substrates, a result of the coating's lower refractive index. Thus, the transmittance at 500 nm increased to approximately 93%. This is approximately or close to the transmittance of the primary eyeglass material CR39, which is neither scratch-resistant nor stain-resistant. The hardness of the uncoated and hard-coated PTU lenses was 4B and HB, respectively. By applying the coating of the present invention, the hardness of the uncoated and hard-coated PTU lenses increased to HB and F, respectively. Furthermore, these coatings exhibited very good to excellent repellency and ease of wiping away permanent markings, including markings from a well-known eyeglass manufacturer. Using the same procedure as described above, the coating was successfully applied to curved PTU lenses, dried, and cured. The same permanent marking test results were obtained as on flat substrates. In fact, permanent markings were much easier to remove from the coating of the present invention compared to lenses (curved surfaces) with commercially available anti-fouling coatings (which were obtained from local eyeglass companies and already coated with anti-fouling coatings). Therefore, the coating of the present invention has the ability to simultaneously serve as both a scratch-resistant layer and a stain-resistant layer on eyeglasses and related products, with the added advantage of enhancing the light transmittance of high refractive index materials.

[0205]

[0206] In Table 5, the components are defined as follows:

[0207] POSS: (Based on the T8 closed cage structure, structure III, but applicable to other cage-like and non-cage-like structures, with the same R group ratio):

[0208] NA1: The 0-7 R groups are Y(CF2). n CF3, where 0-7 R groups are nonfluorinated and contain aryl (e.g., phenyl) and / or alkyl (e.g., methyl, propyl, isobutyl, isooctyl) and / or (poly)siloxane (e.g., low molecular weight siloxanes of 180-800 g / mol), while 1-3 R groups are nonfluorinated and contain one or more nucleophilic groups capable of reacting with polysilazane and causing fragmentation, such as 3-propylamine (NH2 reaction unit), 3-propyl methacrylate (C=O reaction unit), and 2-propoxyethanol (OH reaction unit). Y can be alkyl, aryl, ether, siloxane, or any combination thereof, or a bond—in which case the fluorinated group is directly bonded to the Si of the POSS cage. n is an integer from 0 to 7.

[0209] NA2: The 0-6 R groups are Y(CF2) nCF3, where 1-6 R groups are nonfluorinated and contain aryl and / or alkyl, and / or siloxane, and 1-6 R groups are nonfluorinated and contain alkoxysilyl, such as methoxysilyl and ethoxysilyl. n is an integer from 0 to 7.

[0210] NA3: 1-6 R groups are Y(CF2) n CF3, where 1-6 R groups are nonfluorinated and include alkoxysilyl groups, such as methoxysilyl or ethoxysilyl, and 1-2 groups are nonfluorinated and include one or more nucleophilic groups capable of reacting with polysilazane to cause fragmentation. n is an integer from 0 to 7.

[0211] NA4: 1-6 R groups include alkoxysilyl groups, while 1-2 R groups contain one or more nucleophilic groups that can react with polysilazane to cause fragmentation.

[0212] NA5: All R groups include alkoxysilyl groups and do not have the other groups mentioned above.

[0213] NA6: 5-7 R groups are nonfluorinated and contain aryl (e.g., phenyl) and / or alkyl (e.g., methyl) and / or siloxane, while 1-3 groups are nonfluorinated and include one or more nucleophilic groups capable of reacting with polysilazane to cause fragmentation.

[0214] Polysiloxanes: straight, branched, or cyclic; structure X is an example.

[0215] NA7: 1-3.5 R groups are Y(CF2) n CF3, where 0.5-3 R groups are non-fluorinated and contain aryl or alkyl groups, and 0.5-3 R groups are non-fluorinated and contain alkoxysilyl groups. n is an integer from 0 to 7.

[0216] NA8: 1-3.5 R groups are Y(CF2) n CF3, 0.5-3 R groups are nonfluorinated and include alkoxysilyl groups, while 0.5-1 R groups are nonfluorinated and contain one or more nucleophilic groups capable of reacting with polysilazane to cause fragmentation. n is an integer from 0 to 7.

[0217] In NA7-NA8, R can be hydrogen or contain Si-H, such as 0.5-1 hydrogen atom or 0.5-1 Si-H group.

[0218] NA9: For example, cellulose nanofibers, some of which have hydroxyl groups replaced by organofluorine groups or molecules containing them; and / or some of which have hydroxyl groups replaced by alkyl or aryl groups or molecules containing them, and some of which remain unsubstituted.

[0219] NA10: As in NA9, but some or the remaining hydroxyl groups are replaced by molecules with functional groups that can react with polysilazanes to cause fragmentation, such as 2-propoxyethanol or 3-aminopropyl.

[0220] D1033 represents a polysilazane with structure XI, where X and Y are reported to be 0.33 and 0.67, respectively.

[0221]

[0222] Other components included in the experiment but not listed in the table:

[0223] 1. Nucleophilic catalysts, such as quaternary ammonium salts, are added in amounts of 0.001-2 wt%.

[0224] 2. A leveling agent, such as TG4 or a fluorinated leveling agent (e.g., perfluoropolyether modified TG4), is added in an amount of 0.001-2 wt% of the coating composition.

[0225] 3. The solvent may be an ether, such as tetrahydrofuran, dibutyl ether, or methoxyperfluorobutane, or an aromatic solvent, such as xylene, or other polar aprotic and nonpolar solvents excluding functional groups that can react with polysilazane. The solvent may be mixed or single and constitutes 20-99% of the coating composition.

[0226] 4. Fluorinated analogues can be used to partially or completely replace one or all of the polysilazanes in a given coating composition, thereby producing the improved forms of coatings shown in the table.

[0227] Various additives are designed to perform the same functions as those already described.

[0228] This table serves as a guide for planning experiments, with compositions designed to address identified typical challenges. For example:

[0229] 1. Compared to A, reducing the amounts of NA1 and NA3 and eliminating NA10 in coating B can help better control solution reactivity in the presence of the more reactive PHPS, because the aforementioned additives contain reactive groups. Control of solution reactivity can also benefit from a lower PS+P concentration relative to the solvent. The same applies to coatings E and F.

[0230] 2. Since NA1 and NA3 have returned to their earlier concentrations in coating A, the large volume of D1800 in coating C helps control solution reactivity in the presence of PHPS. Similarly, the use of NA9 in coating E, or the absence of the more reactive NA10 in all compositions containing PHPS, helps control solution reactivity.

[0231] 3. As the concentration of reactive POSS in coating G increases—the sum of NA1, NA4, NA8, and NA10—the concentration of D1800, which has a larger volume and reacts more slowly, increases, thus providing greater flexibility in controlling the reactivity of the solution.

[0232] 4. For example, compared to D1500 RC, the R group in D1800 is longer, thus a more flexible membrane can be obtained using D1800. The same effect can be achieved by selecting the type and length of the R group, for example, by using more flexible (poly)siloxane and polyether groups.

[0233] 5. The nucleophilic (reactive) groups present in NA1, NA3, NA4, NA6, NA8, NA9, and NA10 can covalently bind these groups to the polysilazane backbone, thereby ensuring the uniform distribution of additives in the polysilazane matrix. This is why they can be used at higher concentrations compared to NA2, which lacks reactive nucleophilic groups.

[0234] 6. The alkoxysilanes anchored to NA2-NA5 and NA7-NA8 will ensure faster hydrolysis and curing in the presence of moisture. Since some of these additives also contain reactive groups, the distribution of alkoxysilanes in the coating matrix will be optimized.

[0235] 7. For example, fluorine groups or substituents on NA1 and NA8 can enhance antifouling and low-friction characteristics.

[0236] 8. The selection of aryl and alkyl groups, sometimes in conjunction with organofluorine groups, can improve the stability and dispersibility of nano-additives in coating formulations, which is a first step in achieving uniformity in coating compositions. This is achieved by matching their polarity with that of the polysilazane and the solvent.

[0237] 9. When NA2 contains fluorinated reactive groups, it typically floats to the top of the coating composition. Within a certain concentration range, this can improve antifouling and refractive index properties. The concentration limit in the coating composition can be less than 3%, preferably equal to or less than 1%. The upper limit for NA2 is intentionally kept below, for example, fluorinated POSSes with reactive groups. When the upper concentration limit (to be determined) is exceeded, the fluorinated groups in NA2 and other fluorinated additives may begin to stick together, resulting in a blurred coating.

[0238] 10. Coatings with high concentrations of fluorinated NA2 may be intended to provide antifouling and / or low-friction properties, but not necessarily high transparency.

[0239] The presence of alkoxysilyl groups in 11.NA2 ensures that the silanols generated by the hydrolysis of the additives are covalently bonded to the coating matrix, thus preventing any leaching problems.

[0240] Coating application and curing:

[0241] The coating can be applied by ultrasonic spraying, pneumatic spraying, roller coating or any other process known in the art.

[0242] Curing is accomplished through one or more of the following methods: heating (e.g., infrared heating), plasma, UV, and other known methods that promote hydrolysis to form silanols and polycondensation. Humidity during the curing process is optimized.

[0243] Coating characteristics

[0244] Features of coating

[0245] 1. Refractive index, for example, using an elliptic apparatus or an Abbey 5 refractometer.

[0246] 2. Transmittance

[0247] 3. Chemical analysis to determine functional groups and degree of curing, surface chemicals, and failure mechanisms under UV, damp heat, or chemical and environmental attack. FT-IR, XPS, EDS, and other known techniques can be used.

[0248] 4. Known hardness, wear resistance, and scratch resistance properties of the process, such as friction measurement, pencil hardness, wear tester, etc.

[0249] 5. Features include stain resistance and easy cleaning.

[0250] 6. Water contact angle

[0251] 7. CoF

[0252] 8. Other known methods can be used to identify and optimize coatings for low-friction, anti-fouling, self-cleaning and easy-to-clean transparent coatings.

Claims

1. A composition comprising: i) Based on the weight of the composition, 0.5-30 wt% of a polysilazane component, wherein the polysilazane component is selected from the group consisting of organic polysilazanes, inorganic polysilazanes, and any mixture of two or more organic and / or inorganic polysilazanes; ii) 0.1-15 wt% of POSS comprising at least one nucleophilic group, based on the weight of the composition; iii) Based on the weight of the composition, 0.0001-2 wt% of the quaternary ammonium salt R 1 R 2 R 3 R 4 N + X - , where R 1 R 2 R 3 and R 4 Each of the following is independently selected from the group consisting of alkyl, aryl, arylalkyl, alkoxysilyl, and alkenyl, wherein X is selected from F, Cl, Br, I, PF6 or BF4, and OH; and iv) Inert solvents.

2. The composition according to claim 1, further comprising 1-30 wt% of a curing agent based on the weight of the polysilazane component.

3. The composition according to claim 1, further comprising 0.005-5 wt% of POSS excluding nucleophilic groups, based on the weight of the composition.

4. The composition according to claim 1, further comprising 0.01-1.5 wt% of a leveling agent based on the weight of the composition.

5. The composition according to claim 1, further comprising 0.05-5 wt% of a photoinitiator based on the weight of the composition.

6. The composition according to claim 1, further comprising 0.01-10 wt% nanofibers based on the weight of the composition.

7. The composition according to claim 1, wherein, The at least one nucleophilic group is selected from C=O, OH, NH2, NH, S=O, SH, C=N, epoxy group or C≡N.

8. The composition according to claim 1 or 3, wherein, The POSS comprising at least one nucleophilic group and / or the POSS excluding nucleophilic groups further comprising fluorine substituents.

9. The composition according to claim 8, wherein, The POSS comprising at least one nucleophilic group and / or the POSS excluding nucleophilic groups comprising C1-C5 fluoroalkyl groups with 1-10 fluorine substituents.

10. The composition according to claim 8, wherein, The POSS that does not include nucleophilic groups includes at least one alkoxysilyl group.

11. The composition according to claim 1 or 3, wherein, The POSS comprising at least one nucleophilic group and / or the POSS not comprising a nucleophilic group does not comprise fluorine substituents.

12. The composition according to claim 1 or 3, wherein, The POSS comprising at least one nucleophilic group and / or the POSS excluding nucleophilic groups having a combination of fluorine and nonfluorine substituents.

13. The composition according to claim 1 or 3, wherein, The POSS comprising at least one nucleophilic group and / or the POSS excluding nucleophilic groups comprises a dumbbell-shaped structure.

14. The composition according to any one of claims 1-7, wherein, R 1 R 2 R 3 R 4 Each of them is a tert-butyl group.

15. Use of the composition according to any one of claims 1-14 for coating a substrate.

16. A substrate comprising a coating, wherein, The coating is made at least in part from the composition according to any one of claims 1-14.

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