Boron-containing adhesion promoter compositions and methods thereof

Abstract

The title of the invention is boron-containing adhesion promoter compositions and methods thereof. The adhesion promoter composition includes a substance that can include BH x and a solvent. Embodiments of the adhesion promoter composition can include methods of providing a substrate with a stable surface modification. The adhesion promoter composition can include a surfactant, such as an anionic surfactant, a cationic surfactant, or a non-ionic surfactant, such as polyethylene glycol p-(l,l,3,3-tetramethylbutyl)-phenyl ether, crown ether, polysorbate, or combinations thereof. The adhesion promoter composition can include an activator, such as ferric chloride, trimethyl borate, titanium tetrachloride, or combinations thereof. The substance that includes BH x may include ammonia borane, dimethylamine borane, trimethylamine borane, triethylamine borane, dicyclohexylamine borane, ethylenediamine bisborane, t-butylamine borane, diphenylphosphine borane, pyridine borane, borohydride, or combinations thereof.

Description

Technical Field

[0001] This teaching generally relates to adhesion promoter compositions comprising BH x The substances and solvents; and more specifically, adhesive promoter compositions that can be used with polymers such as ketones (e.g., polyaryletherketones), and methods of applying the compositions. Background Technology

[0002] PAEK polymers, particularly polyetherketoneketone (PEKK) and polyetheretherketone (PEEK), are ideal thermoplastics (TPs) for a wide range of applications, including carbon fiber reinforced polymer (CFRP) composites. Enabling the use of thermoplastics and thermoplastic composites in aircraft and other vehicles offers numerous engineering and manufacturing benefits, including increased yield, thermoforming capabilities, and the elimination of the need for extended tracking / freezing storage. However, the favorable chemical inert properties of TP composites make bonding and finishing surfaces challenging.

[0003] While grinding and high-energy surface preparation techniques, such as plasma, ultraviolet (UV), and sandblasting, can bond TP composites, the resulting high-energy surfaces are relatively unstable and can loosen over time; for example, the beneficial effects of the treatment on bonding may diminish or be lost in less than two months. Furthermore, surface treatment methods involving UV radiation or plasma require specialized equipment. UV and plasma treatments can penetrate the substrate surface and typically require precise tuning and application.

[0004] Therefore, it is desirable to provide a rapid and simple adhesion promoter composition capable of producing surface-modified PAEK polymers for bonding and applying primers / topcoats without any surface abrasion, as well as a method for surface modification. Other desirable properties include the surface-modified PAEK polymer being stable over a long period without degradation, and the surface preparation technique requiring no specialized equipment. Summary of the Invention

[0005] The following is a simplified overview to provide a basic understanding of some aspects of one or more embodiments of this teaching. This overview is not extensive, nor is it intended to identify key or essential elements of this teaching, nor is it intended to describe the scope of this disclosure. Rather, its primary purpose is simply to present one or more concepts in a simplified form as a prelude to the specific embodiments provided later.

[0006] Adhesion accelerator compositions may include BH xThe adhesive promoter composition may include a surfactant. The surfactant may include anionic, cationic, or nonionic surfactants. The surfactant may include polyethylene glycol p-(1,1,3,3-tetramethylbutyl)phenyl ether, crown ethers, polysorbate, or combinations thereof. The adhesive promoter composition may include an activator. The activator may include ferric chloride, trimethyl borate, titanium tetrachloride, or combinations thereof. Containing BH x Substances containing BH may include ammoniaborane. x The substances may include dimethylamine borane, trimethylamine borane, triethylamine borane, dicyclohexylamine borane, ethylenediamine diborane, tert-butylamine borane, diphenylphosphine borane, pyridine borane, borohydrides, or combinations thereof. Solvents may include water, tetrahydrofuran, 2-phenoxyethanol, methanol, ethanol, isopropanol, dimethyl sulfoxide, acetonitrile, phenol, silanes having hydroxyl groups, compounds containing glycidyl groups, divalent esters, ethers, ethylene glycol ethers, or combinations thereof. Solvents may include glycidoxytrimethoxysilane (GTMS). Containing BH x The substances may include ammonia borane, and the solvent may include 2-phenoxyethanol.

[0007] Methods for providing stable surface-modified substrates may include using substrates containing BH x An adhesion promoter composition of a substance and solvent is applied to the surface of a substrate, which may include polyarylether ketone (PAEK). The method also includes allowing the adhesion promoter composition to remain on the surface for about 5 minutes to about 72 hours. The method further includes removing the adhesion promoter composition from the surface by wiping or rinsing. The method also includes drying the surface of the PAEK. Embodiments of the method for providing a stable surface-modified substrate may include applying a coating to the surface of the substrate. The coating may include an epoxy resin, polyurethane, or a polysulfide. Removing the adhesion promoter composition from the surface may include wiping and / or rinsing with a solvent, which may include methyl ethyl ketone (MEK), methyl propyl ketone (MPK), isopropanol (IPA), acetone, water, propylene glycol propyl ether (PGPE), or combinations thereof. The method for providing a stable surface-modified substrate may include heating the adhesion promoter composition to up to 100°C. The CO:C=O ratio of the surface is higher at a surface depth of up to 10 nm compared to the bulk substrate.

[0008] A stable, surface-activated polymer surface includes the surface of a substrate, which may include polyaryletherketone (PAEK), and wherein stability further includes a higher CO:C=O ratio at a surface depth of up to 10 nm compared to the bulk of the substrate. Embodiments of a stable, surface-activated polymer surface include those wherein the CO:C=O ratio remains stable for approximately 6 months to approximately 2 years. The polyaryletherketone (PAEK) may include polyetheretherketone (PEEK) or polyetherketoneketone (PEKK).

[0009] The features, functions, and benefits already discussed can be implemented independently in various implementation schemes or combined in other implementation schemes, as can be seen in the following description for further details of these implementation schemes. Attached Figure Description

[0010] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present teachings and, together with the specification, serve to explain the principles of this disclosure. In the drawings: Figure 1A Applications of structural components, including exemplary activated PAEK compositions for use in aerospace vehicles, are described. Figure 1B Based on this disclosure Figure 1A An exploded view of a portion of an aerospace vehicle.

[0011] Figure 2 This is a flowchart illustrating a method for providing a stable surface-modified substrate according to the present disclosure.

[0012] Figure 3 The X-ray photoelectron spectroscopy (XPS) spectra of the boron region of samples d1a and d1a1 from Example 1 are based on this disclosure.

[0013] It should be noted that some details in the accompanying drawings have been simplified and are intended to facilitate understanding of this teaching rather than to maintain strict structural accuracy, detail, and scale. Detailed Implementation

[0014] Exemplary embodiments of this teaching will now be described in detail, examples of which are illustrated in the accompanying drawings. Where possible, the same reference numerals will be used throughout the drawings to refer to the same, similar, or analogous parts.

[0015] This disclosure provides a method containing BH x Compositions of substances and solvents, and methods for applying adhesion promoter compositions for abrasion-free bonding of various materials (such as ketones), and in specific examples, polyaryletherketones, activated polyaryletherketones, and methods thereof are provided. This disclosure includes: 1) adhesion promoter compositions, 2) stable surface-modified (activated) polyaryletherketone (PAEK) polymers, and 3) methods for applying adhesion promoters and surface activation. One component of the adhesion promoter composition is boron hydride (-BH) xThe chemical solution, in an example, is an adhesion promoter composition based on ammonia borane (AB, NH3-BH3), which can rapidly and easily reduce ketones to produce a modified surface chemical composition containing an increased ratio of carbon-oxygen single bonds (CO) to carbon-oxygen double bonds (C=O) relative to the bulk, while maintaining storage stability. This disclosure also includes application methods—including but not limited to spraying and brushing—and activation parameters—including solvent selection, activation time, and activation temperature.

[0016] PAEK polymers, specifically polyetherketoneketone (PEKK) and polyetheretherketone (PEEK), are ideal thermoplastics (TPs) for a wide range of applications, including carbon fiber reinforced polymer (CFRP) composites. The ability to use thermoplastics, particularly in the aerospace industry (e.g., for aircraft), offers numerous engineering and manufacturing benefits, including lighter weight, sustainability due to the material's end-of-life reshaping and recycling capabilities, rapid cycle times, thermoformability, safety, and economic advantages, reduced labor exposure, and the elimination of the need for extended tracking / freezing storage. The favorable chemical inert properties of TP composites make bonding and finishing surfaces challenging. The compositions and methods described herein aim to provide: 1) a rapid, easy-to-use adhesion promoter composition capable of producing 2) surface-modified PAEK polymers for bonding and applying primers / topcoats without requiring any surface abrasion (no sandblasting, no sandblasting) or high-energy treatments (no plasma, no UV), and 3) a method for surface modification.

[0017] While abrasive or high-energy surface preparation techniques (e.g., sandblasting, plasma, UV + chemical activation) can bond TP composites, the resulting high-energy surfaces are relatively unstable and tend to loosen over time (e.g., <2 months), during which the beneficial effects of the treatment on adhesion diminish or are lost. A key advantage of the adhesion promoter compositions and methods of this disclosure is that the surface-modified PAEK polymers are stable without degradation over a longer period (i.e., >3 months). Furthermore, surface treatment methods involving UV radiation or plasma require specialized equipment. UV and plasma treatments penetrate the surface of the substrate and typically require precise tuning and application. Abrasive and high-energy surface preparation techniques result in additional cleaning steps, higher energy usage, and increased processing time, all of which hinder the adoption of thermoplastics in a wider range of applications.

[0018] The compositions and methods disclosed herein can be used in applications of PAEK thermoplastic parts or composites, such as 1) structural bonding, including co-bonding, secondary bonding, or repair; and / or 2) surface finishing, including paints, primers, and / or sealants. Examples of PAEK-based material systems include PEKK-based matrix and CFRP composites based on the PEEK matrix.

[0019] Commercial applications of this disclosure may further include PEEK-based biomedical implant materials that are currently limited by somatic cell-PEEK surface interactions and insufficient growth.

[0020] This teaching provides: 1) adhesion promoter compositions, 2) stable surface-modified (activated) polyaryletherketone (PAEK) polymers, and 3) methods for applying and (surface) activating adhesion promoters. Generally, PAEK comprises polymers having repeating units of any sequence having an aryl ether segment (-phenyl-O-phenyl-) and an aryl ketone segment (-phenyl-C(=O)-phenyl-), as shown in Schemes 1A and 1B, respectively. For example, PEKK (polyetherketoneketone) has repeating units of aryl ether / aryl ketone / aryl ketone, and PEEK (polyetheretherketone) has repeating units of aryl ether / aryl ether / aryl ketone, as shown in Schemes 1C and 1D, respectively. Scheme 1 shows the chemical structure of polyaryletherketone (PAEK) polymers. 1A) An aryl ether segment containing 2 CO bonds; 1B) An aryl ketone segment containing 1 C=O bond; 1C) A polyetherketoneketone (PEKK) repeating unit containing 2 CO bonds and 2 C=O bonds; 1D) A polyetheretherketone (PEEK) repeating unit containing 4 CO bonds and 1 C=O bond.

[0021] The given sequences of ether and ketone segments determine the chemical state distribution of carbon atoms in the PAEK polymer. Specifically, the chemical state of carbon atoms bonded to oxygen atoms can be defined by N(CO / C=O), which is the ratio of the number of carbon-oxygen single bonds (CO) to the number of carbon-oxygen double bonds (C=O). Each aryl ether segment contains two CO bonds, and each aryl ketone segment contains one C=O bond. As an example, PEKK contains one ether segment (two CO bonds) and two ketone segments (two C=O bonds), and therefore N(CO / C=O) = 1; PEEK contains two ether segments (four CO bonds) and one ketone segment (one C=O bond), and therefore N(CO / C=O) = 4.

[0022] These N (CO / C=O) values ​​relate to the bulk composition. They also typically refer to the surface composition of the unmodified polymer. Here, the surface composition refers to a surface layer with a thickness of approximately 5 to 10 nanometers or less, roughly the layer thickness detected by techniques considered sensitive to surfaces, such as X-ray photoelectron spectroscopy (XPS) or time-of-flight secondary ion mass spectrometry (TOF-SIMS). The bulk composition refers to a layer of approximately 100 to 1000 nanometers or greater.

[0023] Compared to the unmodified polymer, the surface-modified PAEK polymer of this teaching exhibits a higher N(CO / C=O) value in the surface layer than the host polymer. This higher N(CO / C=O) value in the surface layer is achieved through chemical modification (particularly chemical reduction) of a portion of the surface C=O bonds to C-OH or C-OR, where C-OH represents reduction to an alcohol, and C-OR represents other possibilities such as COB- or CO-Si-. Each reduced surface C=O bond removes one C=O bond and simultaneously generates a CO bond, thereby increasing N(CO / C=O). For example, reducing 50% of the C=O bonds on the PEKK surface to C-OH bonds increases N(CO / C=O) from 1 to 3.

[0024] In detail, the two CO / units and two C=O / units with N(CO / C=O)=1 before modification are transformed into three CO / units and one C=O / unit in the surface-modified polymer with N(CO / C=O)=3. Similarly, reducing 50% of the C=O bonds on the PEEK surface increases the number of CO bonds from 4 to 4.5 and decreases the number of C=O bonds from 1 to 0.5, thereby increasing N(CO / C=O) from 4 to 9.

[0025] The surface-modified PAEK polymers disclosed herein may optionally have an elemental surface composition containing about 0.1 atomic% or from about 0.02 atomic% to about 0.5 atomic% boron. The presence of boron is a result of the modification process in which the partially reduced surface C=O bonds are not bonded to hydrogen (i.e., C-OH) but to boron or a chemical structure containing COB-segments. Furthermore, additional CO-Si-segments may be formed when silanes are used as solvents.

[0026] The chemical activation methods described in this article for producing surface-modified PAEK polymers include the use of boron hydride (BH) x The chemical substance is used to chemically reduce the surface of PAEK polymers, where x refers to the number of hydrogen atoms in the compound. The BH-containing compounds used in this disclosure... xA specific example of such a chemical substance is ammoniaborane (AB, NH3BH3). It contains BH... x Other examples of chemical substances include dimethylamineborane, trimethylamineborane, triethylamineborane, dicyclohexylamineborane, ethylenediamine diborane, tert-butylamineborane, diphenylphosphineborane, triphenylphosphineborane, morpholineborane, 2-methylpyridineborane, boran-tetrahydrofuran complexes, such as borohydrides of NaBH4, and pyridineborane.

[0027] Unbound by any particular theory, the underlying mechanism of this approach is thought to be similar to that of amine borane complexes, such as ammonia boranes, which are known in the homogeneous solution-phase organic chemistry literature as mild reducing agents. Their reactivity is lower than that of their borohydride counterparts (e.g., NaBH4), making them suitable for use in protic solvents such as water, alcohols, etc., without rapid decomposition (<6 hours). In solution, amine borane complexes can reduce solvated substances, including nitriles, activated alkenes, ketones, and aldehydes, typically without the need for a catalyst. The mechanism of action can vary depending on the solvent and reaction conditions, but most reductions occur via transfer hydrogenation or through a borohydride process to produce borate esters, followed immediately by alcoholysis. While some mechanistic understanding of solution-state reductions using AB has been demonstrated, the same process / mechanism occurring inhomogeneously at the solid / solution interface is not readily apparent. The heterogeneous reaction at the PAEK surface reduces surface C=O functional groups to C-OR or C-OH functional groups. These functional groups are known to be reactive with many commercial adhesives (epoxy, polyurethane, silicone, etc.) and increase adhesive strength through covalent bonds between the adhesive polymer network and the PAEK surface. Because the reaction occurs only at the surface, the bulk polymer remains unreacted and retains ideal thermal and thermomechanical properties.

[0028] Contains BH x The chemical substances form BH-containing compounds by dissolving in a suitable solvent. x Chemical solutions are used for this purpose. Suitable solvents include water, tetrahydrofuran, 2-phenoxyethanol (2PE), methanol, ethanol, isopropanol, dimethyl sulfoxide, acetonitrile, phenol, and silanes having hydroxyl, alkoxy, silylhydride, glycidyl, and amino groups, such as (3-glycidylpropyl)trimethyl / ethoxysilane, trimethyl / ethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethyl / ethoxysilane, 3-aminopropylsilanetriol, 3-aminopropyltrimethyl / ethoxysilane, 3-aminopropyltrimethyl / ethoxysilane, divalent esters (DBE), polyethylene glycol (PEG) with a molecular weight of 400 to 1000, methoxy polyethylene glycol (MeOPEG), ethers such as diethyl ether, and glycol ethers such as propylene glycol methyl ether (PGME) and propylene glycol n-propyl ether (PGPE). (BH) xThe concentration of the substance solution can be less than 0.1 wt% to 10 wt% or higher, 2 wt% or 5 wt%. One example is 2 wt% AB dissolved in 2PE.

[0029] A solution of boron hydride chemical can be applied to the surface of PAEK polymers by a variety of methods, including but not limited to immersion, dipping, brushing, wiping, spraying, or combinations thereof.

[0030] Chemical reduction treatments are carried out at temperatures ranging from room temperature to up to 95°C for approximately 5 or 15 minutes to up to 72 hours or longer, with shorter residence times required at higher temperatures. In other examples, compared to BH... x The degradation temperature of a substance may be approximately 15°C lower or approximately 10°C lower than the boiling point of the chosen solvent, which could be the highest temperature for chemical reduction. Examples include 30 min at room temperature (25°C), 3 h at room temperature, 6 h at room temperature, overnight at room temperature, 72 h at room temperature, 2 h at 60°C, 15 min at 75°C, 15 min at 95°C, 1 h at 60°C, 6 h at 60°C, 30 min at 75°C, 1 h at 75°C, 2 h at 75°C, 5 min at 95°C, or 30 min at 95°C.

[0031] During the process, the surface may be exposed or covered, or come into contact with a second surface that is also being processed in a sandwich configuration.

[0032] Use containing BH x After chemical solution treatment, the modified PAEK polymer surface is wiped dry. Optionally, the surface is further cleaned with water or a suitable organic solvent such as isopropanol, acetone, methyl ethyl ketone, methyl propyl ketone, or propylene glycol propyl ether. In this step, ketones can be used to inactivate any excess BH. x .

[0033] This method also includes BH containing an activator. x The substance solution is packaged or added just before use. An example is adding 1 part by weight of 3-epoxypropoxypropyl-trimethoxysilane as an activator to 2 wt% AB in 1 part by weight of 2PE. Adding this activator can reduce the treatment time at room temperature from 3 hours to 30 minutes. Other examples of activators include: 1) DBE, and 2) 0.1 mol / L FeCl3 dissolved in 2PE, each used as 1 part by weight and 2 wt% AB in 1 part by weight of 2PE. Other illustrative examples of activators may include TiCl4, B(OH)3, B(OMe)3, Sc(OTf)3, or B(C6F5)3.

[0034] The utility of the compositions and methods disclosed herein lies in applications requiring bonding and / or modification of PAEK polymer surfaces. In its simplest form, such bonding can be achieved by using, for example, an epoxy film adhesive to bond two PAEK polymer surfaces, also known as secondary bonding. In other instances, PAEK can be bonded to cured thermosetting CFRP or metal using epoxy resin adhesives, urethane adhesives, or combinations thereof. Other examples include: 1) bonding a PAEK surface to a “green state” thermosetting CFRP during resin curing, also known as co-bonding; 2) surface finishing of the PAEK polymer with a primer, paint, or sealant; or 3) growth of somatic cells attached to the PAEK surface of a biomedical implant; or 4) surface modification to improve hydrophilicity; or 5) modification refers to surface functionalization to support further surface chemistry / reactivity, e.g., tethering groups to alter surface energy, etc.

[0035] Unmodified PAEK polymer surfaces produce adhesive bonds with low adhesive strength, which is unacceptable for most applications and does not allow for adequate adhesion of primers / topcoats. Therefore, adhesive bond strength tests, such as floating roller peel (FRP), typically give low adhesive strength, indicating failure at the PAEK surface or adhesive interface, also known as bond failure. The double cantilever beam (DCB) method can also be used to measure fracture toughness. In contrast, bonding with surface-modified PAEK polymers as described herein produces high adhesive strength bonds. The adhesive strength of the bond is typically high enough that failure does not occur at the PAEK surface and / or adhesive interface. Instead, failure occurs within the adhesive layer, i.e., cohesive failure; within the PAEK polymer or composite matrix, i.e., substrate failure; or on the opposite side of the adhesive in contact with other substrates, including other materials or untreated PAEK. Similarly, the adhesive strength between the topcoat and the unmodified PAEK surface is low enough to prevent topcoats (such as epoxy primers) from adhering to the surface after any normally required aging tests. On the other hand, the surface-modified PAEK polymers described in this paper not only allow for adhesion of topcoats upon application, but also maintain adhesion through various aging tests, such as water immersion and high temperature or high humidity environments.

[0036] In one example, the method for applying the adhesion promoter composition can be carried out without the use of any external heat. In other examples, the method can be carried out on other PAEK materials such as PEEK. In other examples, Lewis acid additives can be used as reaction catalysts, and the method can be used to bond a first carbon fiber reinforced polymer (CFRP) to a second carbon fiber reinforced polymer (CFRF) using an additional adhesive layer.

[0037] Figure 1AApplications of structural components comprising exemplary activated PAEK compositions applied to aerospace vehicles are described. Figure 1B Based on this disclosure Figure 1A An exploded view of a portion of an aerospace vehicle. The application of the methods and compositions disclosed herein is shown on aerospace vehicle 100, wherein spacecraft substrate 130 uses the activated PAEK composition of this disclosure or includes the adhesion promoters described herein. Figure 1B An exploded view is shown, showing a spacecraft substrate 130 or its surface, with an optional substrate layer 132 and sealing layer 134 on the surface of substrate 130 and / or on structural components of the spacecraft or a portion of the spacecraft. In one example, the adhesive promoter composition of this disclosure or the activated PAEK component is applied to the outer surface of the aerospace vehicle 100. In another example, additional coating layers, such as paint, coatings, or other protective coatings, may be applied inside or outside the sealing layer 134. While exemplary examples of the outer substrate or surface of the aerospace vehicle 100 are shown herein, they are intended as non-limiting examples. Further structural applications or areas may exist in the aerospace vehicle 100 or other structures or spacecraft, where the disclosed compositions may be used.

[0038] The adhesive accelerator compositions disclosed herein include those containing BH x The substances and solvents. In some instances, adhesion promoter compositions include surfactants or activators. Containing BH x The substances may include ammonia borane, or optionally dimethylamine borane, trimethylamine borane, triethylamine borane, dicyclohexylamine borane, ethylenediamine diborane, tert-butylamine borane, diphenylphosphine borane, pyridine borane, sodium borohydride, or combinations thereof. Solvents may include water, tetrahydrofuran, 2-phenoxyethanol, methanol, ethanol, isopropanol, dimethyl sulfoxide, acetonitrile, phenol, ether, ethylene glycol ether, silanes having a hydroxyl group, compounds containing glycidyl groups, or combinations thereof. An exemplary solvent example may include glycidoxytrimethoxysilane (GTMS). Surfactants may include anionic surfactants, cationic surfactants, or nonionic surfactants. Exemplary surfactant examples may include polyethylene glycol p-(1,1,3,3-tetramethylbutyl)-phenyl ether, crown ethers, polysorbates, or combinations thereof. Activators may include ferric chloride.

[0039] Figure 2 This is a flowchart illustrating a method for providing a stable surface modification of a substrate according to the present disclosure. Method 200 includes taking a substrate comprising BH xAn adhesion promoter composition of a substance and solvent is applied to the surface of a substrate comprising polyarylether ketone (PAEK) 202, the adhesion promoter composition is left on the surface for about 5 minutes to about 72 hours 204, the adhesion promoter composition is removed from the surface by rinsing 206, and the rinsed surface-modified PAEK surface is dried 208. In an example, the method 200 for providing a stable surface-modified substrate further includes applying a coating to the surface of the substrate. In an example, the surface may optionally be heated. In an example, the coating composition includes epoxy resin, polyurethane, or polysulfide. Removing the adhesion promoter composition from the surface may include rinsing with a solvent including methyl ethyl ketone (MEK), methyl propyl ketone (MPK), isopropanol (IPA), acetone, water, propylene glycol propyl ether (PGPE), propylene glycol methyl ether (PGME), or combinations thereof. In an example, THF, ethanol, and other glycol ethers, such as propylene glycol methyl ether (PGME), may be used. In other examples, method 200 for providing a stable surface-modified substrate may include heating the adhesion promoter composition to up to 100°C or as previously described. As a result of method 200 for providing a stable surface-modified substrate, the CO:C=O ratio of the surface is higher at a surface depth of up to 10 nm compared to the bulk of the substrate.

[0040] Further examples of adhesion promoter compositions may include the use of ammonia borane (AB) at concentrations between 2% and 5% by weight, or about 3% to about 4% by weight. Further aspects of the method may include applying multiple solution coatings to improve surface coverage, or using different BH-containing... x Compounds, such as dimethylamine borane or trimethylamine borane, are combined with AB. Additional examples of this method may include using solvents such as water, tetrahydrofuran, methanol, ethanol, isopropanol, and acetonitrile to dissolve the adhesion promoter composition, treating the PAEK surface at temperatures up to 95°C to shorten the reaction time, or using room temperature treatment to extend the residence time. DBE is added as an activator at a ratio of 1:2 to 5:4 relative to the AB concentration, or FeCl3 dissolved in water or an alternative carrier solvent (0.1 mol / L) is added at the same ratio. This method may include cleaning one or more surfaces prior to application by rinsing with acetone followed by water or using a mild solvent such as isopropanol, or using different coating methods such as immersion for uniform coverage, dipping to control thickness, brushing / wiping for localized application, and spraying for rapid surface treatment. These examples provide a range of options for tailoring adhesion promoter compositions and modification processes to specific application requirements.

[0041] Optional additions of activators such as DBE and FeCl3 can enhance reactivity in specific environments (e.g., high humidity or low temperature conditions). In examples, activators are used to enhance activity (reaction rate) at lower temperature conditions or to allow for shorter treatment times. After treatment with an adhesion promoter solution, wiping dry with a lint-free cloth or paper towel without applying excessive pressure can be helpful. Immersing the PAEK polymer surface in a solution containing BH... x A method for surface modification without impairing the properties of the substrate is provided in a chemical solution. The process involves immersing the substrate in a solution containing ammonia borane (AB) or other suitable BH. x The solution contains compounds such as dimethylamineborane and trimethylamineborane, dissolved in solvents such as water, tetrahydrofuran, 2-phenoxyethanol, methanol, ethanol, isopropanol, dimethyl sulfoxide, acetonitrile, phenols, silanes with hydroxyl groups (e.g., trimethyl / ethoxy(methoxy)prop-1-en-3-yloxy), and compounds containing glycidyl groups. Immersion can be used when large-area uniform coating coverage or precise control of thickness distribution is required. This method can be used in a variety of applications, such as aerospace for structural bonding, automotive for surface finishing and adhesion promotion, biomedicine for implantable devices, tissue-engineered scaffolds, consumer products such as tapes or coatings, building materials, and more.

[0042] Impregnation is a useful method for applying an adhesion accelerator composition to a PAEK polymer surface. This can be done by sequentially applying one or more coats of the adhesion accelerator solution. Impregnation, compared to immersion (meaning leaving the item in a bath), can be considered a brief soaking and can be removed. Brushing is advantageous as an application method for applying an adhesion accelerator composition to a PAEK polymer surface using one or more brushes, where a soft-bristled brush is used to evenly apply the adhesion accelerator composition solution to the surface without creating excessive pressure or scratches. This method provides uniform coverage while minimizing potential damage to the underlying material or minimizing BH (Browser Hardness). x The amount of solution used.

[0043] Spraying is a method of applying an adhesion promoter composition to a PAEK polymer surface. This technique involves distributing a solution onto the surface in a controlled manner using an atomizer or spray gun. The choice of nozzle size and shape, as well as the pressure and flow rate of the compressed gas and therefore the liquid adhesion promoter, can be adjusted according to specific application requirements. For example, when a large, uniform coverage is required, such as in aerospace applications where bonding multiple components together requires efficient processing times, using a wide-angle nozzle (e.g., 60° or greater) and a moderate pressure setting may be useful.

[0044] Another example involves gently but thoroughly rinsing the modified surface with deionized water for 1–5 minutes at room temperature, followed by air drying using a compressed nitrogen stream. Another example involves cleaning the surface with an organic solvent such as isopropanol (IPA) or acetone for 1–5 minutes at room temperature. In yet another example, the surface can be cleaned using a 1:2 combination of water and an organic solvent (such as IPA or acetone). In some instances where high-purity water or organic solvents are unavailable, the use of alternative cleaning agents such as ethyl acetate, butanone, or cyclohexane is useful. These alternatives may provide similar effectiveness in removing residual reagents. Without being bound by any particular theory, a correlation may exist between PAEK crystallinity and the effectiveness of the rinsing solvent, and in the examples, both PEEK and PEKK2 can be rinsed with any of the solvents mentioned above.

[0045] Methods and Examples This polymer surface modification method is simple in the examples and can be carried out in the ambient atmosphere, spanning a wide range of temperatures and times, without requiring specialized equipment. This composition and method can be illustrated by experimentally measuring the N(CO / C=O) ratio (as previously defined) of the PAEK polymer surface using XPS. Specifically, the XPS photoelectron peak shape of carbon can be fitted to the contributions of CO and C=O bonds, as well as C, C, and several other types of carbon bonds. Through this fitting, the percentage of CO and C=O bonds can be determined, and thus the N(CO / C=O) ratio. This technique is used in the included examples.

[0046] The practicality described in this article can be illustrated by adhesive peel strength testing and cross-cut adhesion testing. Adhesive (peel) strength can be qualitatively assessed by bonding a small sample (approximately 1 inch × 2 inches) to a stainless steel mesh (approximately 3 / 4 inch × 3 inches) using an epoxy film adhesive, and then peeling the mesh off by hand or with pliers to qualitatively assess the adhesive (peel) strength and observe failure modes.

[0047] Adhesive (peel) strength can be quantitatively assessed, but not limited to, using a floating roller peel test following ASTM D3167, to quantitatively determine adhesive peel strength and observe failure modes. Mechanical strength (fracture toughness, flexural strength, shear strength) can be quantitatively assessed, but not limited to, 1) double cantilever beam (DCB) test, 2) short beam bending (SBF), and 3) short beam shear (SBS). A cross-cut adhesion test can be performed where a carbon fiber reinforced PAEK panel is treated with an adhesion promoter, a topcoat is applied and cured, optionally subjected to prolonged aging conditions, and crisscrossed with a razor blade in a cross-cut pattern, followed by the application of tape with a tensile strength of at least 60 oz / inch width. The tape is then peeled off the surface, and topcoat removal is visually assessed. Some of these techniques are used in the following examples.

[0048] Example 1. Surface-modified PEKK composite material The PEKK composite material (sample d1-control) was characterized by XPS. Analysis of the carbon chemical state distribution revealed 9% CO bonds and 6% C=O bonds. Therefore, the N(CO / C=O) of this sample was 1.5. Considering possible surface contaminants and the uncertainties of XPS technology, this is close to the theoretical bulk value of PEKK, 1.0. Next, 2-phenoxyethanol (2PE, containing BH2O) was used... x The sample was brushed with a solution of the chemical substance (possibly a solvent), wherein the 2-phenoxyethanol did not contain dissolved BH2. x The chemical substances were applied. After coating, the surface was 1) covered with a piece of Kapton; 2) heated in an oven at 60°C for 2 hours; 3) left to stand at room temperature overnight; 4) wiped dry; 5) wiped with PGPE; 6) wiped with isopropanol; and 7) dry-wiped (sample d1a). After characterizing the surface by XPS, the same procedure was repeated on the same PEKK composite material, except that 2PE contained 2% by weight of dissolved ammonia borane as a BH-containing compound. x A chemical solution was used to produce a surface-modified PEKK composite material (sample d1a1).

[0049] Figure 3 The X-ray photoelectron spectroscopy (XPS) spectra of the boron regions from samples d1a and d1a1 of Example 1 are based on this disclosure. XPS analysis of the surface of sample d1a showed 9% CO bonds and 8% C=O bonds, yielding N(CO / C=O) = 1.1. This value (1.1) is lower than that of undissolved BH-containing samples. x The value before chemical treatment (1.5) indicates that no surface modification occurred. It is also close to the theoretical bulk value of PEKK (1.0), indicating that the treatment merely cleaned the surface. Furthermore, as... Figure 3 As shown, no boron was observed in the XPS spectrum of sample d1a. Characterization and analysis of sample d1a1 by XPS revealed that the surface contains 19% CO bonds and 2% C=O bonds, resulting in N(CO / C=O) = 9.5. Furthermore, as... Figure 3 As shown, a clear boron peak can be seen in the XPS spectrum of sample d1a1.

[0050] A second sample of the similarly treated PEKK composite (sample d2-treated) showed 18% CO bonds and 3% C=O bonds, resulting in N(CO / C=O) = 6. Considering the uncertainties of XPS technology, the N(CO / C=O) ratios of samples d1a1 and d2-treated were similar. The N(CO / C=O) values ​​of both samples increased relative to the bulk value of 1. This characterization confirms that samples d1a1 and d2-treated are surface-modified PAEK polymers. Furthermore, the optional presence of boron also confirms that the samples are surface-modified PAEK polymers.

[0051] Example 2. Counterexample: Plasma-treated surface-modified PEKK and PEEK composite materials: Table 1 shows the N(CO / C=O) ratios of the PEKK and PEEK composites determined by XPS analysis before treatment (control samples PEKK-5C and PEEK-5C) and after plasma treatment (samples PEKK-1P and PEEK-1P). For the PEKK samples, plasma treatment reduced the N(CO / C=O) ratio from 1.6 to 0.92. Similarly, for the PEEK samples, plasma treatment reduced the N(CO / C=O) ratio from 3.4 to 1.5. Furthermore, plasma treatment also resulted in increased OC=O and CO32-. 2- The formation of the material indicates that plasma treatment chemically oxidizes the polymer surface. In contrast, the modified surfaces provided by the compositions and methods described herein are chemically reduced. These results demonstrate that plasma treatment does not produce surface-modified PAEK polymers according to this teaching. Table 1. XPS results of plasma-treated PEKK and PEEK composites Example 3. Adhesion with surface-modified PEEK composite materials A 1-inch × 2-inch unmodified PEEK composite material (sample 80b) was coated by brushing with a 2% by weight solution of ammonia borane (AB) in 2PE. After coating, the surface was 1) covered with a Kapton sheet; 2) heated in a hot plate, or, in an optional example, in an oven at 95°C for 1 hour; 3) wiped dry; 4) wiped with PGPE; 5) wiped with isopropanol; and 8) dry-wiped. After treatment, the surface-modified PEEK composite was bonded using the following methods: 1) A first 3 / 4 inch × 1 inch piece of Hysol EA9696 epoxy film adhesive (Henkel) was pressed into the center of the sample; 2) A 3 / 4 inch × 3 inch piece of 316 stainless steel wire cloth, 60 × 60 mesh, with an opening of 0.009 inches, was covered; 3) A second 3 / 4 inch × 1 inch piece of Hysol EA9696 epoxy film adhesive was pressed directly into the mesh above the first piece; and 4) The adhesive was cured for 1.5 hours at 125°C in a vacuum bag under a vacuum of 23 inches of mercury, according to the manufacturer's instructions. After curing, the wire cloth was difficult to peel from the surface-modified PEEK composite by hand and pliers were used. The wire cloth was peeled off by tearing off the epoxy resin. The peel strength was qualitatively high, and cohesive failure occurred within the epoxy resin adhesive. No failure was observed at the interface between the surface-modified PEEK composite and the adhesive.

[0052] Example 4. Adhesion of PEEK composite materials: a counterexample to the method.

[0053] A 1-inch × 2-inch piece of unmodified PEEK composite material (sample 90) was coated by brushing with a 5% by weight AB solution in tetrahydrofuran (THF). Following coating, the THF evaporated rapidly (within approximately 10 minutes), leaving a solid crystalline layer of AB on the surface of the PEEK composite material. Therefore, the solution in this sample did not contain BH. xThe chemical substances were then applied. The surface was then: 1) covered with a piece of Kapton; 2) heated in a hot plate oven or oven at 95°C for 1 hour; 3) rinsed with deionized water; and 4) dried. After treatment, the sample was bonded as follows: 1) a first 3 / 4 inch × 1 inch piece of Hysol EA9696 epoxy film adhesive was pressed into the center of the sample; 2) covered with a 3 / 4 inch × 3 inch piece of 316 stainless steel wire cloth, 60 x 60 mesh, with an opening of 0.009 inches; 3) a second 3 / 4 inch × 1 inch piece of Hysol EA9696 epoxy film adhesive was pressed directly into the mesh above the first piece; and 4) the adhesive was cured for 1.5 hours at 125°C in a vacuum bag under a 23-inch mercury vacuum, according to the manufacturer's instructions. After curing, the wire cloth was easily peeled off the PEEK composite by hand. At the polymer surface / adhesive interface, the wire cloth peeled off, and the epoxy adhesive layer detached from the polymer surface. The peel strength was qualitatively low, indicating adhesive failure. This counterexample illustrates the presence of BH x The effect of methods in which chemical substances are in solution.

[0054] Example 5. Adhesive peel strength of surface-modified PEKK composite material.

[0055] An unmodified PEKK composite material (sample 121) measuring 4 inches × 6 inches was coated with a solution of 2% AB by weight in 2PE through five sprays. After coating, the surface was: 1) covered with a Kapton sheet; 2) heated in an oven at 60°C for 2 hours; 3) wiped dry; 4) wiped with PGPE; 5) wiped with isopropanol; and 8) dry-wiped. Following treatment, the surface-modified PEKK composite was bonded in a configuration suitable for the Floating Roll-Off (FRP) test conforming to ASTM D3167 by the following adhesive bonding: 1) A 3-inch × 3.5-inch piece of Hysol EA9696 epoxy film adhesive was pressed onto the treated composite surface, leaving a 1 / 2-inch gap at one end and a 2-inch gap at the other; 2) A 2-inch gap was covered with a piece of Kapton film (used as a crack initiation point); 3) A 3.5-inch × 7-inch piece of 20 mil thick anodized 2024 aluminum was pressed onto the sample, extending 1 inch beyond the Kapton film crack initiation point; and 4) The adhesive was cured for 1.5 hours in a vacuum bag under 23-inch mercury vacuum at 125°C, according to the manufacturer's instructions. After curing, the sample was cut into three 1 / 2-inch wide strips, discarding two sides. The peel strength of the strips was tested using Instron. For the three pieces, the measured adhesive peel strengths were 73.6 lbf / in-width, 76.8 lbf / in-width, and 86.6 lbf / in-width, yielding an average of 79.0 ± 4.5 lbf / in-width. This value is high and nearly equal to the manufacturer's specified adhesive strength of 80 lbf / in-width. Furthermore, visual inspection of the peeled pieces indicated that the failure was due to cohesion within the adhesive. This example quantitatively illustrates the practicality of this disclosure.

[0056] Example 6. Adhesive peel strength of surface-modified PEKK composites: a counterexample to the method.

[0057] A 4-inch × 6-inch unmodified PEKK composite material (sample 222) was coated by brushing with a 2% by weight AB solution in 2PE. After coating, the surface was 1) covered with a Kapton sheet; 2) subjected to BH at room temperature (~20°C). x The solution was in contact with the polymer surface for 3 hours; 3) dried; 4) wiped with PGPE; 5) wiped with isopropanol; and 8) dry-wiped. After treatment, the sample was bonded and tested using the procedure described in Example 4. The peeled strips showed that approximately 20% to 50% of the peeled area exhibited adhesive failure at the polymer surface / adhesive interface. This counterexample illustrates that the treatment time is insufficient to achieve acceptable bonding.

[0058] Examples 7 to 23. Using ammonia borane as a solution containing BH x The substance.

[0059] These examples follow the procedures described in Example 4. The results shown in the table below illustrate variations in treatment time and temperature (Examples 6-12); application methods (Examples 6, 14, and 15); solvents used for ammonia borane (Examples 17-21); and optional adhesives (Example 22), which produce high peel strength bonds with cohesive failure. They also show that 1) surface-modified PEKK surfaces can bond with high adhesive peel strength without adhesive failure after 3 months of treatment (Example 15); and 2) a 2% AB solution in PE can be used after preparation and storage at room temperature for 3 months (Example 16). Table 2. Results of floating roller peeling tests (Examples 7 to 23) Example 24. A solution containing BH was used with ammonia borane as an activator. x The substance.

[0060] A solution of 2% AB in 2PE was prepared. Separately, a solution of 0.08 mol / L FeCl3 in 2PE was prepared as an activator. Just before use, 1 part of the AB solution was mixed with 1 part of the activator solution. This produced a 2PE solution with 1% AB and 0.04 mol / L FeCl3. Next, a 1-inch × 2-inch unmodified PEKK composite material (sample 284) was coated by brushing with the mixed AB / activator solution. After coating, the surface was: 1) kept unexposed at room temperature (~20°C) for 30 minutes; 2) blotted dry; 3) wiped with methyl ethyl ketone; and 4) dry-rubbed. After treatment, the surface-modified PEKK composite material was bonded using the following adhesive bonding methods: 1) a first 3 / 4 inch × 1 inch piece of Hysol EA9696 epoxy film adhesive was pressed into the center of the sample; 2) a 3 / 4 inch × 3 inch piece of 316 stainless steel wire cloth, 60 x 60 mesh, with an opening of 0.009 inches, was covered; 3) a second 3 / 4 inch × 1 inch piece of Hysol EA9696 epoxy film adhesive was pressed directly into the mesh above the first piece; and 4) the adhesive was cured for 1.5 hours at 125°C in a vacuum bag under a 23-inch mercury vacuum, according to the manufacturer's instructions. After curing, the wire cloth was difficult to peel off from the surface-modified PEKK composite material by hand, and pliers were used.

[0061] The fabric was peeled off by tearing off the epoxy resin. The peel strength was qualitatively high, indicating cohesive failure within the epoxy adhesive. No adhesive failure was observed at the surface-modified PEKK composite / adhesive interface. This example (1% AB / 2PE at room temperature for 30 min) demonstrates the effectiveness of incorporating an activator such as FeCl3, compared to Example 5 (2 wt% AB / 2PE at room temperature for 3 hours, which showed adhesive failure).

[0062] Example 25. Boronhydride (NaBH4) as a solution containing BH x The uses of the substance.

[0063] This embodiment follows the procedure in Example 2, using PEKK composite material. The solution contains BH. x The substance is 5% by weight NaBH4 dissolved in deionized water, with 1% by weight Triton-X100 added to improve the wettability of the solution on the surface of the composite material.

[0064] Two samples were treated. The first sample (sample 76) was treated at room temperature for 16 hours (overnight). The second sample (sample 77) was treated at 95°C for 1 hour and then left at room temperature overnight. Both samples were difficult to peel and exhibited cohesive failure in the epoxy adhesive.

[0065] Example 26. Dimethylamineborane as a BH-containing compound x The uses of the substance.

[0066] This example follows the procedure in Example 2, using the PEKK composite material. A solution of 5% by weight dimethylamine borane (DMAB) in tetrahydrofuran (THF) was prepared and applied to the surface of the composite material. After approximately 5 minutes at room temperature, the THF evaporated. The sample (sample 26) was then heated to 45°C until the DMAB melted. It was then cooled and left to stand at room temperature overnight. Peeling indicated cohesive failure of the epoxy adhesive.

[0067] Example 27: A general method for using an adhesion promoter to enhance the adhesion of topcoat.

[0068] A solution of 2% by weight of ammonia borane (AB) in 2-phenoxyethanol (2PE) was prepared by magnetic mixing under ambient conditions. The solution was then brushed onto a clean, unmodified PEKK composite surface and left to stand for 12 hours under ambient conditions. After 12 hours, the panel was wiped clean using PGPE and a PGPE-based solvent gel until no residue remained. The now-modified panel was then sprayed with an epoxy primer, PPG Aerospace's DeSoto 512X310 urethane-compatible chromium-free epoxy primer (further referred to as DeSoto), and cured according to the relevant product instructions. After curing, the panel underwent a cross-cut adhesion test. The panel was crisscrossed with a cross-cut pattern, 3M tape #250 was applied to the crisscross lines, and then removed to reveal any failed DeSoto adhesion. After visual evaluation, the panel was immersed in deionized water under ambient conditions for 7 days, dried, crisscrossed, and the adhesion was tested in the same manner at different locations on the same panel. Finally, the panel underwent a 30-day condensation humidity test, maintained at 49°C and 100% relative humidity. After 30 days, a final cross-cut adhesion test was performed at another untested point on the same panel. The table below shows the solvents and associated AB concentrations, processing conditions, and adhesion performance used in the specific embodiments. Table 3: Treatment Solution of Example 27 Table 4: Results of bonding of primer and topcoat using surface-modified PAEK (see Example 27 and Table 3) Additional aspects of this disclosure include an adhesion promoter composition for modifying PAEK-based polymers, the composition comprising BH... x It consists of substances, solvents, optional activators, and optional surfactants. Containing BH xThe substances may be ammonia borane (AB, NH3BH3), dimethylamine borane, trimethylamine borane, triethylamine borane, dicyclohexylamine borane, ethylenediamine diborane, tert-butylamine borane, diphenylphosphine borane, triphenylphosphine borane, morpholine borane, 2-methylpyridine borane, borane-tetrahydrofuran complexes, pyridine borane, borohydrides such as NaBH4, and mixtures thereof. The solvent, optional activator, and optional surfactant shall be free of ketones, imides, phthalonitriles, and / or acid anhydrides. Solvents may include water, tetrahydrofuran, 2-phenoxyethanol (2PE), methanol, ethanol, isopropanol, dimethyl sulfoxide, acetonitrile, phenol, silanes with hydroxyl groups, alkoxy groups, silyl hydride groups, glycidyl groups, and amino groups, such as (3-glycidylpropyl)trimethyl / ethoxysilane, trimethyl / ethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethyl / ethoxysilane, 3-aminopropylsilanetriol, 3-aminopropyltrimethyl / ethoxysilane, 3-aminopropyltrimethyl / ethoxysilane, divalent esters (DBE), polyethylene glycol (PEG) with a molecular weight of 400-1000, methoxy polyethylene glycol (MeOPEG), ethers, ethylene glycol ethers, propylene glycol n-propyl ether (PGPE), and mixtures thereof. Exemplary examples of optional activators may be 3-epoxypropoxypropyltrimethoxysilane, FeCl3, TiCl4, B(OMe)3, B(OH)3, DBE, N-(2-aminoethyl)-3-aminopropyltrimeth / ethoxysilane, 3-aminopropylsilanetriol, 3-aminopropoxytrimeth / ethoxysilane, 3-aminopropyltrimeth / ethoxysilane, and mixtures thereof. In the examples, optional surfactants may be anionic, cationic, or nonionic surfactants, such as Triton X-100, crown ethers, polysorbates, and mixtures thereof. The solvent contains BH. xThe concentration of the substance is from about 0.1% by weight to about 50% by weight, or from about 0.5% by weight to about 10% by weight, or from about 1% by weight to about 5% by weight. In an example of an adhesion accelerator composition, it contains about 2% by weight of AB in 2PE. The adhesion accelerator composition can be applied to a PAEK surface by immersion, dipping, brushing, wiping, spraying, or a combination thereof. The adhesion accelerator composition can be applied and activated under ambient conditions. Optionally, the adhesion accelerator composition can be heated to up to 100°C or as described above before, during, or after application. The adhesion accelerator composition can be applied to the surface and left to remain for about 5 minutes to about 72 hours, or about 10 minutes to about 8 hours. The adhesion accelerator composition can be removed from the surface by wiping, rinsing, and / or drying after application and activation before subsequent coatings are bonded to the surface. Rinsing solvents can include MEK, MPK, IPA, acetone, water, PGPE, and mixtures thereof. The adhesion accelerator composition can be used to promote adhesion to epoxy-based / epoxy-containing coatings / adhesives / substrates, polyurethane-based / polyurethane-containing coatings / adhesives / substrates, polysulfide-based / polysulfide-containing coatings / adhesives / substrates, any other hydroxyl-reactive polymer adhesives / coatings, or combinations thereof. The adhesion accelerator composition can be provided or supplied as a premixed solution or a two-part kit, wherein the premixed solution has a shelf life of about 3 months, about 6 months, about 12 months, or about 24 months. Once mixed, the two-part kit has a shelf life of about 1 day, about 1 week, about 1 month, about 3 months, about 6 months, or about 12 months. The adhesion accelerator composition enables secondary bonding of PAEK-based thermoplastic substrates and / or composites to PAEK-based thermoplastic substrates and / or composites for aerospace applications, or enables secondary and co-bonding of PAEK-based thermoplastic substrates and / or composites to thermosetting substrates and / or composites for aerospace applications. Furthermore, adhesion promoter compositions can enable primers and topcoats to bond to PAEK-based thermoplastic surfaces / substrates and / or composites for aerospace applications, bond cells to PAEK-based biomedical implants / devices, or surface modify PAEK-based substrates and / or composites. In examples, surface modification can include attaching functional groups to a surface to alter hydrophobicity, hydrophilicity, or surface energy.

[0069] An additional aspect of this disclosure provides an environmentally stable surface-modified PAEK polymer substrate and / or composite material having a higher ratio of carbon-oxygen single bonds (CO) to carbon-oxygen double bonds (C=O) at its surface than in the bulk, and optionally containing boron and / or silicon at the surface. The C=O bonds may be present at the surface or due to ketone functional groups on the surface. CO may be in the form of COR, where R is H, a B-containing group, a Si-containing group, or other hydrocarbon groups. The surface-modified PAEK polymer substrate and / or composite material can be stable under environmental conditions for about 1 day, about 1 week, about 1 month, about 3 months, about 6 months, about 9 months, about 12 months, or about 2 years. The disclosed method for producing stable surface-modified PAEK polymer substrates and / or composite materials may include using BH… x The adhesive accelerator is used to treat the surface, allowing the adhesive accelerator to remain and / or to be removed.

[0070] This invention includes, specifically, the following provisions.

[0071] Clause 1. An adhesion promoter composition comprising: Includes BH x substances; and Solvent.

[0072] Clause 2. The adhesion promoter composition according to Clause 1 further comprises a surfactant.

[0073] Clause 3. The adhesion promoter composition according to Clause 1, further comprising an activator.

[0074] Clause 4. The adhesion promoter composition according to Clause 1, wherein the composition comprises BH x The substances include ammoniaborane.

[0075] Clause 5. The adhesion promoter composition according to Clause 1, wherein the composition comprises BH x The substances include dimethylamine borane, trimethylamine borane, triethylamine borane, dicyclohexylamine borane, ethylenediamine diborane, tert-butylamine borane, diphenylphosphine borane, pyridine borane, borohydrides, or combinations thereof.

[0076] Clause 6. The adhesion promoter composition according to Clause 1, wherein the solvent comprises water, tetrahydrofuran, 2-phenoxyethanol, methanol, ethanol, isopropanol, dimethyl sulfoxide, acetonitrile, phenol, silane having a hydroxyl group, compound containing glycidyl group, divalent ester, ether, ethylene glycol ether or a combination thereof.

[0077] Clause 7. The adhesion promoter composition according to Clause 1, wherein the solvent comprises glycidoxytrimethoxysilane (GTMS).

[0078] Clause 8. The adhesion promoter composition according to Clause 2, wherein the surfactant comprises anionic surfactant, cationic surfactant or nonionic surfactant.

[0079] Clause 9. The adhesion promoter composition according to Clause 2, wherein the surfactant comprises polyethylene glycol p-(1,1,3,3-tetramethylbutyl)-phenyl ether, crown ether, polysorbate, or a combination thereof.

[0080] Clause 10. The adhesion promoter composition according to Clause 3, wherein the activator comprises ferric chloride, trimethyl borate, titanium tetrachloride, or a combination thereof.

[0081] Clause 11. The adhesion promoter composition according to Clause 1, wherein the composition comprises BH x The substances include ammonia borane, and the solvent includes 2-phenoxyethanol.

[0082] Clause 12. A method (200) for providing a stable surface-modified substrate (130), comprising: This will include BH x An adhesive promoter composition of a substance and a solvent is applied to the surface (202) of a substrate (130) including polyarylether ketone (PAEK); Allow the adhesion promoter composition to remain on the surface for about 5 minutes to about 72 hours (204); The adhesion promoter composition (206) is removed from the surface by wiping and rinsing; and Dry the surface of the PAEK (208).

[0083] Clause 13. The method (200) for providing a stable surface-modified substrate (130) as described in Clause 12, further comprising applying a coating to the surface of the substrate (130).

[0084] Clause 14. The method (200) for providing a stable surface-modified substrate (130) according to Clause 13, wherein the coating comprises an epoxy resin, polyurethane, or polysulfide.

[0085] Clause 15. A method (200) for providing a stable surface-modified substrate (130) according to Clause 12, wherein removing the adhesion promoter composition from the surface comprises wiping and / or rinsing (206) with a solvent including methyl ethyl ketone (MEK), methyl propyl ketone (MPK), isopropanol (IPA), acetone, water, propylene glycol propyl ether (PGPE), or combinations thereof.

[0086] Clause 16. The method (200) for providing a stable surface-modified substrate (130) according to Clause 12, further comprising heating the adhesion promoter composition to up to 100°C.

[0087] Clause 17. The method (200) for providing a stable surface-modified substrate (130) according to Clause 12, wherein the CO:C=O ratio of the surface is higher at a surface depth of up to 10 nm compared to the bulk of the substrate (130).

[0088] Clause 18. A stable, surface-activated polymer surface comprising: The surface of a substrate (130) including polyaryletherketone (PAEK); and wherein: Compared to the bulk of the substrate (130), the CO:C=O ratio of the surface is higher at a surface depth of up to 10 nm.

[0089] Clause 19. A stable surface-activated polymer surface as described in Clause 18, wherein the CO:C=O ratio remains stable for about 6 months to about 2 years.

[0090] Clause 20. A stable, surface-activated polymer surface as described in Clause 18, wherein the polyaryletherketone (PAEK) comprises polyetheretherketone (PEEK) or polyetherketoneketone (PEKK).

[0091] While this teaching has been shown with respect to one or more embodiments, changes and / or modifications may be made to the illustrated embodiments without departing from the spirit and scope of the appended claims. For example, it is understood that although the process is described as a series of actions or events, this teaching is not limited to the order of these actions or events. Some actions may occur in a different order and / or simultaneously with other actions or events not described herein. Furthermore, not all process stages need to implement the method according to one or more aspects or embodiments of this teaching. It is understood that structural objects and / or processing stages may be added, or existing structural objects and / or processing stages may be removed or modified. Furthermore, one or more actions depicted herein may be performed in one or more separate actions and / or stages. Additionally, where the terms “including,” “includes,” “having,” “has,” “with,” or variations thereof are used in the detailed specification and claims, these terms are intended to include in a manner similar to “comprising.” The term “at least one of” is used to refer to one or more of the listed items that may be selected. Furthermore, in the discussion and claims herein, the terms “on” and “one on the other” used for two materials indicate that there is at least some contact between the materials, while “over” indicates that the materials are very close, but there may be one or more additional intervening materials, making contact possible but not necessary. Neither “on” nor “over” implies any directionality as used herein. The term “conformal” describes a coating material in which the conformal material maintains the angle of the underlying material. The term “about” indicates that the listed values ​​may vary, as long as the change does not cause the process or structure to be inconsistent with the illustrated embodiment. The terms “coupled,” “coupled,” “connect,” “connection,” “connected,” “in connection with,” and “connecting” mean “in direct connection with” or “in connection with via one or more intermediate elements or members.”Finally, the terms "exemplary" or "illustrative" indicate that the description is used as an example and not implying that it is ideal. Other embodiments of this teaching will likely be apparent to those skilled in the art upon consideration of the specification and practice disclosed herein. It is intended that the specification and embodiments be considered exemplary only, and the true scope and spirit of this teaching are indicated by the claims.

Claims

1. An adhesion promoter composition comprising: Includes BH x Substances; and Solvent.

2. The adhesion promoter composition according to claim 1, further comprising a surfactant.

3. The adhesion promoter composition according to claim 1, further comprising an activator.

4. The adhesion promoter composition according to claim 1, wherein the composition contains BH x The substances include ammoniaborane.

5. The adhesion promoter composition according to claim 1, wherein the composition contains BH x The substances include dimethylamine borane, trimethylamine borane, triethylamine borane, dicyclohexylamine borane, ethylenediamine diborane, tert-butylamine borane, diphenylphosphine borane, pyridine borane, borohydrides, or combinations thereof.

6. The adhesion promoter composition according to claim 1, wherein the solvent comprises water, tetrahydrofuran, 2-phenoxyethanol, methanol, ethanol, isopropanol, dimethyl sulfoxide, acetonitrile, phenol, silane having a hydroxyl group, compound containing glycidyl group, divalent ester, ether, ethylene glycol ether or a combination thereof.

7. The adhesion promoter composition according to claim 1, wherein the solvent comprises glycidoxytrimethoxysilane (GTMS).

8. The adhesion promoter composition according to claim 2, wherein the surfactant comprises anionic surfactant, cationic surfactant or nonionic surfactant.

9. The adhesion promoter composition according to claim 2, wherein the surfactant comprises polyethylene glycol p-(1,1,3,3-tetramethylbutyl)-phenyl ether, crown ether, polysorbate, or a combination thereof.

10. The adhesion promoter composition according to claim 3, wherein the activator comprises ferric chloride, trimethyl borate, titanium tetrachloride, or a combination thereof.

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